refactor(transcoding): update default command handling and add codec support for transcoding

Signed-off-by: Deluan <deluan@navidrome.org>

.dockerignore

@@ -15,4 +15,5 @@ dist
 binaries
 cache
 music
+music.old
 !Dockerfile

.gitignore

@@ -20,6 +20,7 @@ cache/*
 coverage.out
 dist
 music
+music.old
 *.db*
 .gitinfo
 docker-compose.yml

adapters/deezer/client_auth_test.go

@@ -252,7 +252,7 @@ var _ = Describe("JWT Authentication", func() {
 
 			// Writer goroutine
 			wg.Go(func() {
-				for i := 0; i < 100; i++ {
+				for i := range 100 {
 					cache.set(fmt.Sprintf("token-%d", i), 1*time.Hour)
 					time.Sleep(1 * time.Millisecond)
 				}
@@ -260,7 +260,7 @@ var _ = Describe("JWT Authentication", func() {
 
 			// Reader goroutine
 			wg.Go(func() {
-				for i := 0; i < 100; i++ {
+				for range 100 {
 					cache.get()
 					time.Sleep(1 * time.Millisecond)
 				}

adapters/gotaglib/gotaglib.go

@@ -49,6 +49,7 @@ func (e extractor) Version() string {
 func (e extractor) extractMetadata(filePath string) (*metadata.Info, error) {
 	f, close, err := e.openFile(filePath)
 	if err != nil {
+		log.Warn("gotaglib: Error reading metadata from file. Skipping", "filePath", filePath, err)
 		return nil, err
 	}
 	defer close()
@@ -64,6 +65,7 @@ func (e extractor) extractMetadata(filePath string) (*metadata.Info, error) {
 		Channels:   int(props.Channels),
 		SampleRate: int(props.SampleRate),
 		BitDepth:   int(props.BitsPerSample),
+		Codec:      props.Codec,
 	}
 
 	// Convert normalized tags to lowercase keys (go-taglib returns UPPERCASE keys)
@@ -254,7 +256,7 @@ func parseTIPL(tags map[string][]string) {
 	}
 	var currentRole string
 	var currentValue []string
-	for _, part := range strings.Split(tipl[0], " ") {
+	for part := range strings.SplitSeq(tipl[0], " ") {
 		if _, ok := tiplMapping[part]; ok {
 			addRole(currentRole, currentValue)
 			currentRole = part

adapters/lastfm/agent.go

@@ -31,6 +31,12 @@ var ignoredContent = []string{
 	`<a href="https://www.last.fm/music/`,
 }
 
+var lastFMReadMoreRegex = regexp.MustCompile(`\s*<a href="https://www\.last\.fm/music/[^"]*">Read more on Last\.fm</a>\.?`)
+
+func cleanContent(content string) string {
+	return strings.TrimSpace(lastFMReadMoreRegex.ReplaceAllString(content, ""))
+}
+
 type lastfmAgent struct {
 	ds           model.DataStore
 	sessionKeys  *agents.SessionKeys
@@ -95,7 +101,7 @@ func (l *lastfmAgent) GetAlbumInfo(ctx context.Context, name, artist, mbid strin
 		resp.MBID = a.MBID
 		resp.URL = a.URL
 		if isValidContent(a.Description.Summary) {
-			resp.Description = strings.TrimSpace(a.Description.Summary)
+			resp.Description = cleanContent(a.Description.Summary)
 			return &resp, nil
 		}
 		log.Debug(ctx, "LastFM/album.getInfo returned empty/ignored description, trying next language", "album", name, "artist", artist, "lang", lang)
@@ -171,7 +177,7 @@ func (l *lastfmAgent) GetArtistBiography(ctx context.Context, id, name, mbid str
 			return "", err
 		}
 		if isValidContent(a.Bio.Summary) {
-			return strings.TrimSpace(a.Bio.Summary), nil
+			return cleanContent(a.Bio.Summary), nil
 		}
 		log.Debug(ctx, "LastFM/artist.getInfo returned empty/ignored biography, trying next language", "artist", name, "lang", lang)
 	}

adapters/lastfm/agent_test.go

@@ -80,7 +80,7 @@ var _ = Describe("lastfmAgent", func() {
 		It("returns the biography", func() {
 			f, _ := os.Open("tests/fixtures/lastfm.artist.getinfo.json")
 			httpClient.Res = http.Response{Body: f, StatusCode: 200}
-			Expect(agent.GetArtistBiography(ctx, "123", "U2", "")).To(Equal("U2 é uma das mais importantes bandas de rock de todos os tempos. Formada em 1976 em Dublin, composta por Bono (vocalista  e guitarrista), The Edge (guitarrista, pianista e backing vocal), Adam Clayton (baixista), Larry Mullen, Jr. (baterista e percussionista).\n\nDesde a década de 80, U2 é uma das bandas mais populares no mundo. Seus shows são únicos e um verdadeiro festival de efeitos especiais, além de serem um dos que mais arrecadam anualmente. <a href=\"https://www.last.fm/music/U2\">Read more on Last.fm</a>"))
+			Expect(agent.GetArtistBiography(ctx, "123", "U2", "")).To(Equal("U2 é uma das mais importantes bandas de rock de todos os tempos. Formada em 1976 em Dublin, composta por Bono (vocalista  e guitarrista), The Edge (guitarrista, pianista e backing vocal), Adam Clayton (baixista), Larry Mullen, Jr. (baterista e percussionista).\n\nDesde a década de 80, U2 é uma das bandas mais populares no mundo. Seus shows são únicos e um verdadeiro festival de efeitos especiais, além de serem um dos que mais arrecadam anualmente."))
 			Expect(httpClient.RequestCount).To(Equal(1))
 			Expect(httpClient.SavedRequest.URL.Query().Get("artist")).To(Equal("U2"))
 		})
@@ -535,7 +535,7 @@ var _ = Describe("lastfmAgent", func() {
 			Expect(agent.GetAlbumInfo(ctx, "Believe", "Cher", "03c91c40-49a6-44a7-90e7-a700edf97a62")).To(Equal(&agents.AlbumInfo{
 				Name:        "Believe",
 				MBID:        "03c91c40-49a6-44a7-90e7-a700edf97a62",
-				Description: "Believe is the twenty-third studio album by American singer-actress Cher, released on November 10, 1998 by Warner Bros. Records. The RIAA certified it Quadruple Platinum on December 23, 1999, recognizing four million shipments in the United States; Worldwide, the album has sold more than 20 million copies, making it the biggest-selling album of her career. In 1999 the album received three Grammy Awards nominations including \"Record of the Year\", \"Best Pop Album\" and winning \"Best Dance Recording\" for the single \"Believe\". It was released by Warner Bros. Records at the end of 1998. The album was executive produced by Rob <a href=\"https://www.last.fm/music/Cher/Believe\">Read more on Last.fm</a>.",
+				Description: "Believe is the twenty-third studio album by American singer-actress Cher, released on November 10, 1998 by Warner Bros. Records. The RIAA certified it Quadruple Platinum on December 23, 1999, recognizing four million shipments in the United States; Worldwide, the album has sold more than 20 million copies, making it the biggest-selling album of her career. In 1999 the album received three Grammy Awards nominations including \"Record of the Year\", \"Best Pop Album\" and winning \"Best Dance Recording\" for the single \"Believe\". It was released by Warner Bros. Records at the end of 1998. The album was executive produced by Rob",
 				URL:         "https://www.last.fm/music/Cher/Believe",
 			}))
 			Expect(httpClient.RequestCount).To(Equal(1))

adapters/lastfm/auth_router.go

@@ -65,7 +65,7 @@ func (s *Router) routes() http.Handler {
 }
 
 func (s *Router) getLinkStatus(w http.ResponseWriter, r *http.Request) {
-	resp := map[string]interface{}{
+	resp := map[string]any{
 		"apiKey": s.apiKey,
 	}
 	u, _ := request.UserFrom(r.Context())

adapters/listenbrainz/agent.go

@@ -118,12 +118,129 @@ func (l *listenBrainzAgent) IsAuthorized(ctx context.Context, userId string) boo
 	return err == nil && sk != ""
 }
 
+func (l *listenBrainzAgent) GetArtistURL(ctx context.Context, id, name, mbid string) (string, error) {
+	if mbid == "" {
+		return "", agents.ErrNotFound
+	}
+
+	url, err := l.client.getArtistUrl(ctx, mbid)
+	if err != nil {
+		return "", err
+	}
+	return url, nil
+}
+
+func (l *listenBrainzAgent) GetArtistTopSongs(ctx context.Context, id, artistName, mbid string, count int) ([]agents.Song, error) {
+	resp, err := l.client.getArtistTopSongs(ctx, mbid, count)
+	if err != nil {
+		return nil, err
+	}
+	if len(resp) == 0 {
+		return nil, agents.ErrNotFound
+	}
+
+	res := make([]agents.Song, len(resp))
+	for i, t := range resp {
+		mbid := ""
+		if len(t.ArtistMBIDs) > 0 {
+			mbid = t.ArtistMBIDs[0]
+		}
+
+		res[i] = agents.Song{
+			Album:      t.ReleaseName,
+			AlbumMBID:  t.ReleaseMBID,
+			Artist:     t.ArtistName,
+			ArtistMBID: mbid,
+			Duration:   t.DurationMs,
+			Name:       t.RecordingName,
+			MBID:       t.RecordingMbid,
+		}
+	}
+	return res, nil
+}
+
+func (l *listenBrainzAgent) GetSimilarArtists(ctx context.Context, id string, name string, mbid string, limit int) ([]agents.Artist, error) {
+	if mbid == "" {
+		return nil, agents.ErrNotFound
+	}
+
+	resp, err := l.client.getSimilarArtists(ctx, mbid, limit)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(resp) == 0 {
+		return nil, agents.ErrNotFound
+	}
+
+	artists := make([]agents.Artist, len(resp))
+	for i, artist := range resp {
+		artists[i] = agents.Artist{
+			MBID: artist.MBID,
+			Name: artist.Name,
+		}
+	}
+
+	return artists, nil
+}
+
+func (l *listenBrainzAgent) GetSimilarSongsByTrack(ctx context.Context, id string, name string, artist string, mbid string, limit int) ([]agents.Song, error) {
+	if mbid == "" {
+		return nil, agents.ErrNotFound
+	}
+
+	resp, err := l.client.getSimilarRecordings(ctx, mbid, limit)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(resp) == 0 {
+		return nil, agents.ErrNotFound
+	}
+
+	songs := make([]agents.Song, len(resp))
+	for i, song := range resp {
+		songs[i] = agents.Song{
+			Album:     song.ReleaseName,
+			AlbumMBID: song.ReleaseMBID,
+			Artist:    song.Artist,
+			MBID:      song.MBID,
+			Name:      song.Name,
+		}
+	}
+
+	return songs, nil
+}
+
 func init() {
 	conf.AddHook(func() {
 		if conf.Server.ListenBrainz.Enabled {
 			scrobbler.Register(listenBrainzAgentName, func(ds model.DataStore) scrobbler.Scrobbler {
-				return listenBrainzConstructor(ds)
+				// This is a workaround for the fact that a (Interface)(nil) is not the same as a (*listenBrainzAgent)(nil)
+				// See https://go.dev/doc/faq#nil_error
+				a := listenBrainzConstructor(ds)
+				if a != nil {
+					return a
+				}
+				return nil
+			})
+
+			agents.Register(listenBrainzAgentName, func(ds model.DataStore) agents.Interface {
+				// This is a workaround for the fact that a (Interface)(nil) is not the same as a (*listenBrainzAgent)(nil)
+				// See https://go.dev/doc/faq#nil_error
+				a := listenBrainzConstructor(ds)
+				if a != nil {
+					return a
+				}
+				return nil
 			})
 		}
 	})
 }
+
+var (
+	_ agents.ArtistTopSongsRetriever      = (*listenBrainzAgent)(nil)
+	_ agents.ArtistURLRetriever           = (*listenBrainzAgent)(nil)
+	_ agents.ArtistSimilarRetriever       = (*listenBrainzAgent)(nil)
+	_ agents.SimilarSongsByTrackRetriever = (*listenBrainzAgent)(nil)
+)

adapters/listenbrainz/agent_test.go

@@ -4,11 +4,14 @@ import (
 	"bytes"
 	"context"
 	"encoding/json"
+	"errors"
 	"io"
 	"net/http"
+	"os"
 	"time"
 
 	"github.com/navidrome/navidrome/consts"
+	"github.com/navidrome/navidrome/core/agents"
 	"github.com/navidrome/navidrome/core/scrobbler"
 	"github.com/navidrome/navidrome/model"
 	"github.com/navidrome/navidrome/tests"
@@ -162,4 +165,279 @@ var _ = Describe("listenBrainzAgent", func() {
 			Expect(err).To(MatchError(scrobbler.ErrUnrecoverable))
 		})
 	})
+
+	Describe("GetArtistUrl", func() {
+		var agent *listenBrainzAgent
+		var httpClient *tests.FakeHttpClient
+		BeforeEach(func() {
+			httpClient = &tests.FakeHttpClient{}
+			client := newClient("BASE_URL", httpClient)
+			agent = listenBrainzConstructor(ds)
+			agent.client = client
+		})
+
+		It("returns artist url when MBID present", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.artist.metadata.homepage.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+			Expect(agent.GetArtistURL(ctx, "", "", "d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56")).To(Equal("http://projectmili.com/"))
+			Expect(httpClient.RequestCount).To(Equal(1))
+			Expect(httpClient.SavedRequest.URL.Query().Get("artist_mbids")).To(Equal("d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56"))
+		})
+
+		It("returns error when url not present", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.artist.metadata.no_homepage.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+			_, err := agent.GetArtistURL(ctx, "", "", "7c2cc610-f998-43ef-a08f-dae3344b8973")
+			Expect(err).To(HaveOccurred())
+			Expect(httpClient.RequestCount).To(Equal(1))
+			Expect(httpClient.SavedRequest.URL.Query().Get("artist_mbids")).To(Equal("7c2cc610-f998-43ef-a08f-dae3344b8973"))
+		})
+
+		It("returns error when fetch calls fails", func() {
+			httpClient.Err = errors.New("error")
+			_, err := agent.GetArtistURL(ctx, "", "", "7c2cc610-f998-43ef-a08f-dae3344b8973")
+			Expect(err).To(HaveOccurred())
+			Expect(httpClient.RequestCount).To(Equal(1))
+			Expect(httpClient.SavedRequest.URL.Query().Get("artist_mbids")).To(Equal("7c2cc610-f998-43ef-a08f-dae3344b8973"))
+		})
+
+		It("returns error when ListenBrainz returns an error", func() {
+			httpClient.Res = http.Response{
+				Body:       io.NopCloser(bytes.NewBufferString(`{"code": 400,"error": "artist mbid 1 is not valid."}`)),
+				StatusCode: 400,
+			}
+			_, err := agent.GetArtistURL(ctx, "", "", "7c2cc610-f998-43ef-a08f-dae3344b8973")
+			Expect(err).To(HaveOccurred())
+			Expect(httpClient.RequestCount).To(Equal(1))
+			Expect(httpClient.SavedRequest.URL.Query().Get("artist_mbids")).To(Equal("7c2cc610-f998-43ef-a08f-dae3344b8973"))
+		})
+	})
+
+	Describe("GetTopSongs", func() {
+		var agent *listenBrainzAgent
+		var httpClient *tests.FakeHttpClient
+		BeforeEach(func() {
+			httpClient = &tests.FakeHttpClient{}
+			client := newClient("BASE_URL", httpClient)
+			agent = listenBrainzConstructor(ds)
+			agent.client = client
+		})
+
+		It("returns error when fetch calls", func() {
+			httpClient.Err = errors.New("error")
+			_, err := agent.GetArtistTopSongs(ctx, "", "", "d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56", 1)
+			Expect(err).To(HaveOccurred())
+			Expect(httpClient.RequestCount).To(Equal(1))
+			Expect(httpClient.SavedRequest.URL.Path).To(Equal("/1/popularity/top-recordings-for-artist/d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56"))
+		})
+
+		It("returns an error on listenbrainz error", func() {
+			httpClient.Res = http.Response{
+				Body:       io.NopCloser(bytes.NewBufferString(`{"code":400,"error":"artist_mbid: '1' is not a valid uuid"}`)),
+				StatusCode: 400,
+			}
+			_, err := agent.GetArtistTopSongs(ctx, "", "", "1", 1)
+			Expect(err).To(HaveOccurred())
+			Expect(httpClient.RequestCount).To(Equal(1))
+			Expect(httpClient.SavedRequest.URL.Path).To(Equal("/1/popularity/top-recordings-for-artist/1"))
+		})
+
+		It("returns all tracks when asked", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.popularity.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+			data, err := agent.GetArtistTopSongs(ctx, "", "", "d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56", 2)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(data).To(Equal([]agents.Song{
+				{
+					ID:         "",
+					Name:       "world.execute(me);",
+					MBID:       "9980309d-3480-4e7e-89ce-fce971a452be",
+					Artist:     "Mili",
+					ArtistMBID: "d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56",
+					Album:      "Miracle Milk",
+					AlbumMBID:  "38a8f6e1-0e34-4418-a89d-78240a367408",
+					Duration:   211912,
+				},
+				{
+					ID:         "",
+					Name:       "String Theocracy",
+					MBID:       "afa2c83d-b17f-4029-b9da-790ea9250cf9",
+					Artist:     "Mili",
+					ArtistMBID: "d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56",
+					Album:      "String Theocracy",
+					AlbumMBID:  "d79a38e3-7016-4f39-a31a-f495ce914b8e",
+					Duration:   174000,
+				},
+			}))
+		})
+
+		It("returns only one track when prompted", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.popularity.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+			data, err := agent.GetArtistTopSongs(ctx, "", "", "d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56", 1)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(data).To(Equal([]agents.Song{
+				{
+					ID:         "",
+					Name:       "world.execute(me);",
+					MBID:       "9980309d-3480-4e7e-89ce-fce971a452be",
+					Artist:     "Mili",
+					ArtistMBID: "d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56",
+					Album:      "Miracle Milk",
+					AlbumMBID:  "38a8f6e1-0e34-4418-a89d-78240a367408",
+					Duration:   211912,
+				},
+			}))
+		})
+	})
+
+	Describe("GetSimilarArtists", func() {
+		var agent *listenBrainzAgent
+		var httpClient *tests.FakeHttpClient
+		baseUrl := "https://labs.api.listenbrainz.org/similar-artists/json?algorithm=session_based_days_9000_session_300_contribution_5_threshold_15_limit_50_skip_30&artist_mbids="
+		mbid := "db92a151-1ac2-438b-bc43-b82e149ddd50"
+
+		BeforeEach(func() {
+			httpClient = &tests.FakeHttpClient{}
+			client := newClient("BASE_URL", httpClient)
+			agent = listenBrainzConstructor(ds)
+			agent.client = client
+		})
+
+		It("returns error when fetch calls", func() {
+			httpClient.Err = errors.New("error")
+			_, err := agent.GetSimilarArtists(ctx, "", "", mbid, 1)
+			Expect(err).To(HaveOccurred())
+			Expect(httpClient.RequestCount).To(Equal(1))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(baseUrl + mbid))
+		})
+
+		It("returns an error on listenbrainz error", func() {
+			httpClient.Res = http.Response{
+				Body:       io.NopCloser(bytes.NewBufferString(`Bad request`)),
+				StatusCode: 400,
+			}
+			_, err := agent.GetSimilarArtists(ctx, "", "", "1", 1)
+			Expect(err).To(HaveOccurred())
+			Expect(httpClient.RequestCount).To(Equal(1))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(baseUrl + "1"))
+		})
+
+		It("returns all data on call", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.labs.similar-artists.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+
+			resp, err := agent.GetSimilarArtists(ctx, "", "", "db92a151-1ac2-438b-bc43-b82e149ddd50", 2)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(httpClient.RequestCount).To(Equal(1))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(baseUrl + mbid))
+			Expect(resp).To(Equal([]agents.Artist{
+				{MBID: "f27ec8db-af05-4f36-916e-3d57f91ecf5e", Name: "Michael Jackson"},
+				{MBID: "7364dea6-ca9a-48e3-be01-b44ad0d19897", Name: "a-ha"},
+			}))
+		})
+
+		It("returns subset of data on call", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.labs.similar-artists.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+
+			resp, err := agent.GetSimilarArtists(ctx, "", "", "db92a151-1ac2-438b-bc43-b82e149ddd50", 1)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(httpClient.RequestCount).To(Equal(1))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(baseUrl + mbid))
+			Expect(resp).To(Equal([]agents.Artist{
+				{MBID: "f27ec8db-af05-4f36-916e-3d57f91ecf5e", Name: "Michael Jackson"},
+			}))
+		})
+	})
+
+	Describe("GetSimilarTracks", func() {
+		var agent *listenBrainzAgent
+		var httpClient *tests.FakeHttpClient
+		mbid := "8f3471b5-7e6a-48da-86a9-c1c07a0f47ae"
+		baseUrl := "https://labs.api.listenbrainz.org/similar-recordings/json?algorithm=session_based_days_9000_session_300_contribution_5_threshold_15_limit_50_skip_30&recording_mbids="
+
+		BeforeEach(func() {
+			httpClient = &tests.FakeHttpClient{}
+			client := newClient("BASE_URL", httpClient)
+			agent = listenBrainzConstructor(ds)
+			agent.client = client
+		})
+
+		It("returns error when fetch calls", func() {
+			httpClient.Err = errors.New("error")
+			_, err := agent.GetSimilarSongsByTrack(ctx, "", "", "", mbid, 1)
+			Expect(err).To(HaveOccurred())
+			Expect(httpClient.RequestCount).To(Equal(1))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(baseUrl + mbid))
+		})
+
+		It("returns an error on listenbrainz error", func() {
+			httpClient.Res = http.Response{
+				Body:       io.NopCloser(bytes.NewBufferString(`Bad request`)),
+				StatusCode: 400,
+			}
+			_, err := agent.GetSimilarSongsByTrack(ctx, "", "", "", "1", 1)
+			Expect(err).To(HaveOccurred())
+			Expect(httpClient.RequestCount).To(Equal(1))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(baseUrl + "1"))
+		})
+
+		It("returns all data on call", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.labs.similar-recordings.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+
+			resp, err := agent.GetSimilarSongsByTrack(ctx, "", "", "", mbid, 2)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(httpClient.RequestCount).To(Equal(1))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(baseUrl + mbid))
+			Expect(resp).To(Equal([]agents.Song{
+				{
+					ID:         "",
+					Name:       "Take On Me",
+					MBID:       "12f65dca-de8f-43fe-a65d-f12a02aaadf3",
+					ISRC:       "",
+					Artist:     "a‐ha",
+					ArtistMBID: "",
+					Album:      "Hunting High and Low",
+					AlbumMBID:  "4ec07fe8-e7c6-3106-a0aa-fdf92f13f7fc",
+					Duration:   0,
+				},
+				{
+					ID:         "",
+					Name:       "Wake Me Up Before You Go‐Go",
+					MBID:       "80033c72-aa19-4ba8-9227-afb075fec46e",
+					ISRC:       "",
+					Artist:     "Wham!",
+					ArtistMBID: "",
+					Album:      "Make It Big",
+					AlbumMBID:  "c143d542-48dc-446b-b523-1762da721638",
+					Duration:   0,
+				},
+			}))
+		})
+
+		It("returns subset of data on call", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.labs.similar-recordings.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+
+			resp, err := agent.GetSimilarSongsByTrack(ctx, "", "", "", mbid, 1)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(httpClient.RequestCount).To(Equal(1))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(baseUrl + mbid))
+			Expect(resp).To(Equal([]agents.Song{
+				{
+					ID:         "",
+					Name:       "Take On Me",
+					MBID:       "12f65dca-de8f-43fe-a65d-f12a02aaadf3",
+					ISRC:       "",
+					Artist:     "a‐ha",
+					ArtistMBID: "",
+					Album:      "Hunting High and Low",
+					AlbumMBID:  "4ec07fe8-e7c6-3106-a0aa-fdf92f13f7fc",
+					Duration:   0,
+				},
+			}))
+		})
+	})
 })

adapters/listenbrainz/auth_router.go

@@ -60,7 +60,7 @@ func (s *Router) routes() http.Handler {
 }
 
 func (s *Router) getLinkStatus(w http.ResponseWriter, r *http.Request) {
-	resp := map[string]interface{}{}
+	resp := map[string]any{}
 	u, _ := request.UserFrom(r.Context())
 	key, err := s.sessionKeys.Get(r.Context(), u.ID)
 	if err != nil && !errors.Is(err, model.ErrNotFound) {
@@ -107,7 +107,7 @@ func (s *Router) link(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	_ = rest.RespondWithJSON(w, http.StatusOK, map[string]interface{}{"status": resp.Valid, "user": resp.UserName})
+	_ = rest.RespondWithJSON(w, http.StatusOK, map[string]any{"status": resp.Valid, "user": resp.UserName})
 }
 
 func (s *Router) unlink(w http.ResponseWriter, r *http.Request) {

adapters/listenbrainz/auth_router_test.go

@@ -37,7 +37,7 @@ var _ = Describe("ListenBrainz Auth Router", func() {
 			req = httptest.NewRequest("GET", "/listenbrainz/link", nil)
 			r.getLinkStatus(resp, req)
 			Expect(resp.Code).To(Equal(http.StatusOK))
-			var parsed map[string]interface{}
+			var parsed map[string]any
 			Expect(json.Unmarshal(resp.Body.Bytes(), &parsed)).To(BeNil())
 			Expect(parsed["status"]).To(Equal(false))
 		})
@@ -47,7 +47,7 @@ var _ = Describe("ListenBrainz Auth Router", func() {
 			req = httptest.NewRequest("GET", "/listenbrainz/link", nil)
 			r.getLinkStatus(resp, req)
 			Expect(resp.Code).To(Equal(http.StatusOK))
-			var parsed map[string]interface{}
+			var parsed map[string]any
 			Expect(json.Unmarshal(resp.Body.Bytes(), &parsed)).To(BeNil())
 			Expect(parsed["status"]).To(Equal(true))
 		})
@@ -80,7 +80,7 @@ var _ = Describe("ListenBrainz Auth Router", func() {
 			req = httptest.NewRequest("PUT", "/listenbrainz/link", strings.NewReader(`{"token": "tok-1"}`))
 			r.link(resp, req)
 			Expect(resp.Code).To(Equal(http.StatusOK))
-			var parsed map[string]interface{}
+			var parsed map[string]any
 			Expect(json.Unmarshal(resp.Body.Bytes(), &parsed)).To(BeNil())
 			Expect(parsed["status"]).To(Equal(true))
 			Expect(parsed["user"]).To(Equal("ListenBrainzUser"))

adapters/listenbrainz/client.go

@@ -2,16 +2,29 @@ package listenbrainz
 
 import (
 	"bytes"
+	"cmp"
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"net/http"
 	"net/url"
 	"path"
+	"slices"
 
+	"github.com/navidrome/navidrome/conf"
 	"github.com/navidrome/navidrome/log"
 )
 
+const (
+	lbzApiUrl = "https://api.listenbrainz.org/1/"
+	labsBase  = "https://labs.api.listenbrainz.org/"
+)
+
+var (
+	ErrorNotFound = errors.New("listenbrainz: not found")
+)
+
 type listenBrainzError struct {
 	Code    int
 	Message string
@@ -62,14 +75,14 @@ const (
 
 type listenInfo struct {
 	ListenedAt    int           `json:"listened_at,omitempty"`
-	TrackMetadata trackMetadata `json:"track_metadata,omitempty"`
+	TrackMetadata trackMetadata `json:"track_metadata"`
 }
 
 type trackMetadata struct {
 	ArtistName     string         `json:"artist_name,omitempty"`
 	TrackName      string         `json:"track_name,omitempty"`
 	ReleaseName    string         `json:"release_name,omitempty"`
-	AdditionalInfo additionalInfo `json:"additional_info,omitempty"`
+	AdditionalInfo additionalInfo `json:"additional_info"`
 }
 
 type additionalInfo struct {
@@ -88,7 +101,7 @@ func (c *client) validateToken(ctx context.Context, apiKey string) (*listenBrain
 	r := &listenBrainzRequest{
 		ApiKey: apiKey,
 	}
-	response, err := c.makeRequest(ctx, http.MethodGet, "validate-token", r)
+	response, err := c.makeAuthenticatedRequest(ctx, http.MethodGet, "validate-token", r)
 	if err != nil {
 		return nil, err
 	}
@@ -104,7 +117,7 @@ func (c *client) updateNowPlaying(ctx context.Context, apiKey string, li listenI
 		},
 	}
 
-	resp, err := c.makeRequest(ctx, http.MethodPost, "submit-listens", r)
+	resp, err := c.makeAuthenticatedRequest(ctx, http.MethodPost, "submit-listens", r)
 	if err != nil {
 		return err
 	}
@@ -122,7 +135,7 @@ func (c *client) scrobble(ctx context.Context, apiKey string, li listenInfo) err
 			Payload:    []listenInfo{li},
 		},
 	}
-	resp, err := c.makeRequest(ctx, http.MethodPost, "submit-listens", r)
+	resp, err := c.makeAuthenticatedRequest(ctx, http.MethodPost, "submit-listens", r)
 	if err != nil {
 		return err
 	}
@@ -141,7 +154,7 @@ func (c *client) path(endpoint string) (string, error) {
 	return u.String(), nil
 }
 
-func (c *client) makeRequest(ctx context.Context, method string, endpoint string, r *listenBrainzRequest) (*listenBrainzResponse, error) {
+func (c *client) makeAuthenticatedRequest(ctx context.Context, method string, endpoint string, r *listenBrainzRequest) (*listenBrainzResponse, error) {
 	b, _ := json.Marshal(r.Body)
 	uri, err := c.path(endpoint)
 	if err != nil {
@@ -177,3 +190,189 @@ func (c *client) makeRequest(ctx context.Context, method string, endpoint string
 
 	return &response, nil
 }
+
+type lbzHttpError struct {
+	Code  int    `json:"code"`
+	Error string `json:"error"`
+}
+
+func (c *client) makeGenericRequest(ctx context.Context, method string, endpoint string, params url.Values) (*http.Response, error) {
+	req, _ := http.NewRequestWithContext(ctx, method, lbzApiUrl+endpoint, nil)
+	req.Header.Add("Content-Type", "application/json; charset=UTF-8")
+	req.URL.RawQuery = params.Encode()
+
+	log.Trace(ctx, fmt.Sprintf("Sending ListenBrainz %s request", req.Method), "url", req.URL)
+	resp, err := c.hc.Do(req)
+
+	if err != nil {
+		return nil, err
+	}
+
+	// On a 200 code, there is no code. Decode using using error message if it exists
+	if resp.StatusCode != 200 {
+		defer resp.Body.Close()
+		decoder := json.NewDecoder(resp.Body)
+
+		var lbzError lbzHttpError
+		jsonErr := decoder.Decode(&lbzError)
+
+		if jsonErr != nil {
+			return nil, fmt.Errorf("ListenBrainz: HTTP Error, Status: (%d)", resp.StatusCode)
+		}
+
+		return nil, &listenBrainzError{Code: lbzError.Code, Message: lbzError.Error}
+	}
+
+	return resp, err
+}
+
+type artistMetadataResult struct {
+	Rels struct {
+		OfficialHomepage string `json:"official homepage,omitempty"`
+	} `json:"rels,omitzero"`
+}
+
+func (c *client) getArtistUrl(ctx context.Context, mbid string) (string, error) {
+	params := url.Values{}
+	params.Add("artist_mbids", mbid)
+	resp, err := c.makeGenericRequest(ctx, http.MethodGet, "metadata/artist", params)
+	if err != nil {
+		return "", err
+	}
+
+	defer resp.Body.Close()
+	decoder := json.NewDecoder(resp.Body)
+
+	var response []artistMetadataResult
+	jsonErr := decoder.Decode(&response)
+	if jsonErr != nil {
+		return "", fmt.Errorf("ListenBrainz: HTTP Error, Status: (%d)", resp.StatusCode)
+	}
+
+	if len(response) == 0 || response[0].Rels.OfficialHomepage == "" {
+		return "", ErrorNotFound
+	}
+
+	return response[0].Rels.OfficialHomepage, nil
+}
+
+type trackInfo struct {
+	ArtistName    string   `json:"artist_name"`
+	ArtistMBIDs   []string `json:"artist_mbids"`
+	DurationMs    uint32   `json:"length"`
+	RecordingName string   `json:"recording_name"`
+	RecordingMbid string   `json:"recording_mbid"`
+	ReleaseName   string   `json:"release_name"`
+	ReleaseMBID   string   `json:"release_mbid"`
+}
+
+func (c *client) getArtistTopSongs(ctx context.Context, mbid string, count int) ([]trackInfo, error) {
+	resp, err := c.makeGenericRequest(ctx, http.MethodGet, "popularity/top-recordings-for-artist/"+mbid, url.Values{})
+	if err != nil {
+		return nil, err
+	}
+
+	defer resp.Body.Close()
+	decoder := json.NewDecoder(resp.Body)
+
+	var response []trackInfo
+	jsonErr := decoder.Decode(&response)
+	if jsonErr != nil {
+		return nil, fmt.Errorf("ListenBrainz: HTTP Error, Status: (%d)", resp.StatusCode)
+	}
+
+	if len(response) > count {
+		return response[0:count], nil
+	}
+
+	return response, nil
+}
+
+type artist struct {
+	MBID  string `json:"artist_mbid"`
+	Name  string `json:"name"`
+	Score int    `json:"score"`
+}
+
+func (c *client) getSimilarArtists(ctx context.Context, mbid string, limit int) ([]artist, error) {
+	req, _ := http.NewRequestWithContext(ctx, http.MethodGet, labsBase+"similar-artists/json", nil)
+	req.Header.Add("Content-Type", "application/json; charset=UTF-8")
+	req.URL.RawQuery = url.Values{
+		"artist_mbids": []string{mbid}, "algorithm": []string{conf.Server.ListenBrainz.ArtistAlgorithm},
+	}.Encode()
+
+	log.Trace(ctx, fmt.Sprintf("Sending ListenBrainz Labs %s request", req.Method), "url", req.URL)
+	resp, err := c.hc.Do(req)
+
+	if err != nil {
+		return nil, err
+	}
+
+	defer resp.Body.Close()
+	decoder := json.NewDecoder(resp.Body)
+
+	var artists []artist
+	jsonErr := decoder.Decode(&artists)
+	if jsonErr != nil {
+		return nil, fmt.Errorf("ListenBrainz: HTTP Error, Status: (%d)", resp.StatusCode)
+	}
+
+	if len(artists) > limit {
+		return artists[:limit], nil
+	}
+
+	return artists, nil
+}
+
+type recording struct {
+	MBID        string `json:"recording_mbid"`
+	Name        string `json:"recording_name"`
+	Artist      string `json:"artist_credit_name"`
+	ReleaseName string `json:"release_name"`
+	ReleaseMBID string `json:"release_mbid"`
+	Score       int    `json:"score"`
+}
+
+func (c *client) getSimilarRecordings(ctx context.Context, mbid string, limit int) ([]recording, error) {
+	req, _ := http.NewRequestWithContext(ctx, http.MethodGet, labsBase+"similar-recordings/json", nil)
+	req.Header.Add("Content-Type", "application/json; charset=UTF-8")
+	req.URL.RawQuery = url.Values{
+		"recording_mbids": []string{mbid}, "algorithm": []string{conf.Server.ListenBrainz.TrackAlgorithm},
+	}.Encode()
+
+	log.Trace(ctx, fmt.Sprintf("Sending ListenBrainz Labs %s request", req.Method), "url", req.URL)
+	resp, err := c.hc.Do(req)
+
+	if err != nil {
+		return nil, err
+	}
+
+	defer resp.Body.Close()
+	decoder := json.NewDecoder(resp.Body)
+
+	var recordings []recording
+	jsonErr := decoder.Decode(&recordings)
+	if jsonErr != nil {
+		return nil, fmt.Errorf("ListenBrainz: HTTP Error, Status: (%d)", resp.StatusCode)
+	}
+
+	// For whatever reason, labs API isn't guaranteed to give results in the proper order
+	// and may also provide duplicates. See listenbrainz.labs.similar-recordings-real-out-of-order.json
+	// generated from https://labs.api.listenbrainz.org/similar-recordings/json?recording_mbids=8f3471b5-7e6a-48da-86a9-c1c07a0f47ae&algorithm=session_based_days_180_session_300_contribution_5_threshold_15_limit_50_skip_30
+	slices.SortFunc(recordings, func(a, b recording) int {
+		return cmp.Or(
+			cmp.Compare(b.Score, a.Score), // Sort by score descending
+			cmp.Compare(a.MBID, b.MBID),   // Then by MBID ascending to ensure deterministic order for duplicates
+		)
+	})
+
+	recordings = slices.CompactFunc(recordings, func(a, b recording) bool {
+		return a.MBID == b.MBID
+	})
+
+	if len(recordings) > limit {
+		return recordings[:limit], nil
+	}
+
+	return recordings, nil
+}

adapters/listenbrainz/client_test.go

@@ -4,10 +4,13 @@ import (
 	"bytes"
 	"context"
 	"encoding/json"
+	"fmt"
 	"io"
 	"net/http"
 	"os"
 
+	"github.com/navidrome/navidrome/conf"
+	"github.com/navidrome/navidrome/conf/configtest"
 	"github.com/navidrome/navidrome/tests"
 	. "github.com/onsi/ginkgo/v2"
 	. "github.com/onsi/gomega"
@@ -117,4 +120,345 @@ var _ = Describe("client", func() {
 			})
 		})
 	})
+
+	Context("getArtistUrl", func() {
+		baseUrl := "https://api.listenbrainz.org/1/metadata/artist?"
+		It("handles a malformed request with status code", func() {
+			httpClient.Res = http.Response{
+				Body:       io.NopCloser(bytes.NewBufferString(`{"code": 400,"error": "artist mbid 1 is not valid."}`)),
+				StatusCode: 400,
+			}
+			_, err := client.getArtistUrl(context.Background(), "1")
+			Expect(err.Error()).To(Equal("ListenBrainz error(400): artist mbid 1 is not valid."))
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(baseUrl + "artist_mbids=1"))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+		})
+
+		It("handles a malformed request without meaningful body", func() {
+			httpClient.Res = http.Response{
+				Body:       io.NopCloser(bytes.NewBufferString(``)),
+				StatusCode: 501,
+			}
+			_, err := client.getArtistUrl(context.Background(), "1")
+			Expect(err.Error()).To(Equal("ListenBrainz: HTTP Error, Status: (501)"))
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(baseUrl + "artist_mbids=1"))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+		})
+
+		It("It returns not found when the artist has no official homepage", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.artist.metadata.no_homepage.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+			_, err := client.getArtistUrl(context.Background(), "7c2cc610-f998-43ef-a08f-dae3344b8973")
+			Expect(err.Error()).To(Equal("listenbrainz: not found"))
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(baseUrl + "artist_mbids=7c2cc610-f998-43ef-a08f-dae3344b8973"))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+		})
+
+		It("It returns data when the artist has a homepage", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.artist.metadata.homepage.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+			url, err := client.getArtistUrl(context.Background(), "d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56")
+			Expect(err).ToNot(HaveOccurred())
+			Expect(url).To(Equal("http://projectmili.com/"))
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(baseUrl + "artist_mbids=d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56"))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+		})
+	})
+
+	Context("getArtistTopSongs", func() {
+		baseUrl := "https://api.listenbrainz.org/1/popularity/top-recordings-for-artist/"
+
+		It("handles a malformed request with status code", func() {
+			httpClient.Res = http.Response{
+				Body:       io.NopCloser(bytes.NewBufferString(`{"code":400,"error":"artist_mbid: '1' is not a valid uuid"}`)),
+				StatusCode: 400,
+			}
+			_, err := client.getArtistTopSongs(context.Background(), "1", 50)
+			Expect(err.Error()).To(Equal("ListenBrainz error(400): artist_mbid: '1' is not a valid uuid"))
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(baseUrl + "1"))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+		})
+
+		It("handles a malformed request without standard body", func() {
+			httpClient.Res = http.Response{
+				Body:       io.NopCloser(bytes.NewBufferString(``)),
+				StatusCode: 500,
+			}
+			_, err := client.getArtistTopSongs(context.Background(), "1", 1)
+			Expect(err.Error()).To(Equal("ListenBrainz: HTTP Error, Status: (500)"))
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(baseUrl + "1"))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+		})
+
+		It("It returns all tracks when given the opportunity", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.popularity.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+			data, err := client.getArtistTopSongs(context.Background(), "d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56", 5)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(data).To(Equal([]trackInfo{
+				{
+					ArtistName:    "Mili",
+					ArtistMBIDs:   []string{"d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56"},
+					DurationMs:    211912,
+					RecordingName: "world.execute(me);",
+					RecordingMbid: "9980309d-3480-4e7e-89ce-fce971a452be",
+					ReleaseName:   "Miracle Milk",
+					ReleaseMBID:   "38a8f6e1-0e34-4418-a89d-78240a367408",
+				},
+				{
+					ArtistName:    "Mili",
+					ArtistMBIDs:   []string{"d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56"},
+					DurationMs:    174000,
+					RecordingName: "String Theocracy",
+					RecordingMbid: "afa2c83d-b17f-4029-b9da-790ea9250cf9",
+					ReleaseName:   "String Theocracy",
+					ReleaseMBID:   "d79a38e3-7016-4f39-a31a-f495ce914b8e",
+				},
+			}))
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(baseUrl + "d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56"))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+		})
+
+		It("It returns a subset of tracks when allowed", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.popularity.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+			data, err := client.getArtistTopSongs(context.Background(), "d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56", 1)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(data).To(Equal([]trackInfo{
+				{
+					ArtistName:    "Mili",
+					ArtistMBIDs:   []string{"d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56"},
+					DurationMs:    211912,
+					RecordingName: "world.execute(me);",
+					RecordingMbid: "9980309d-3480-4e7e-89ce-fce971a452be",
+					ReleaseName:   "Miracle Milk",
+					ReleaseMBID:   "38a8f6e1-0e34-4418-a89d-78240a367408",
+				},
+			}))
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(baseUrl + "d2a92ee2-27ce-4e71-bfc5-12e34fe8ef56"))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+		})
+	})
+
+	Context("getSimilarArtists", func() {
+		var algorithm string
+
+		BeforeEach(func() {
+			algorithm = "session_based_days_9000_session_300_contribution_5_threshold_15_limit_50_skip_30"
+			DeferCleanup(configtest.SetupConfig())
+		})
+
+		getUrl := func(mbid string) string {
+			return fmt.Sprintf("https://labs.api.listenbrainz.org/similar-artists/json?algorithm=%s&artist_mbids=%s", algorithm, mbid)
+		}
+
+		mbid := "db92a151-1ac2-438b-bc43-b82e149ddd50"
+
+		It("handles a malformed request with status code", func() {
+			httpClient.Res = http.Response{
+				Body:       io.NopCloser(bytes.NewBufferString(`Bad request`)),
+				StatusCode: 400,
+			}
+			_, err := client.getSimilarArtists(context.Background(), "1", 2)
+			Expect(err.Error()).To(Equal("ListenBrainz: HTTP Error, Status: (400)"))
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(getUrl("1")))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+		})
+
+		It("handles real data properly", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.labs.similar-artists.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+			resp, err := client.getSimilarArtists(context.Background(), mbid, 2)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(getUrl(mbid)))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+			Expect(resp).To(Equal([]artist{
+				{MBID: "f27ec8db-af05-4f36-916e-3d57f91ecf5e", Name: "Michael Jackson", Score: 800},
+				{MBID: "7364dea6-ca9a-48e3-be01-b44ad0d19897", Name: "a-ha", Score: 792},
+			}))
+		})
+
+		It("truncates data when requested", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.labs.similar-artists.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+			resp, err := client.getSimilarArtists(context.Background(), "db92a151-1ac2-438b-bc43-b82e149ddd50", 1)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(getUrl(mbid)))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+			Expect(resp).To(Equal([]artist{
+				{MBID: "f27ec8db-af05-4f36-916e-3d57f91ecf5e", Name: "Michael Jackson", Score: 800},
+			}))
+		})
+
+		It("fetches a different endpoint when algorithm changes", func() {
+			algorithm = "session_based_days_1825_session_300_contribution_3_threshold_10_limit_100_filter_True_skip_30"
+			conf.Server.ListenBrainz.ArtistAlgorithm = algorithm
+
+			f, _ := os.Open("tests/fixtures/listenbrainz.labs.similar-artists.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+			resp, err := client.getSimilarArtists(context.Background(), mbid, 2)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(getUrl(mbid)))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+			Expect(resp).To(Equal([]artist{
+				{MBID: "f27ec8db-af05-4f36-916e-3d57f91ecf5e", Name: "Michael Jackson", Score: 800},
+				{MBID: "7364dea6-ca9a-48e3-be01-b44ad0d19897", Name: "a-ha", Score: 792},
+			}))
+		})
+	})
+
+	Context("getSimilarRecordings", func() {
+		var algorithm string
+
+		BeforeEach(func() {
+			algorithm = "session_based_days_9000_session_300_contribution_5_threshold_15_limit_50_skip_30"
+			DeferCleanup(configtest.SetupConfig())
+		})
+
+		getUrl := func(mbid string) string {
+			return fmt.Sprintf("https://labs.api.listenbrainz.org/similar-recordings/json?algorithm=%s&recording_mbids=%s", algorithm, mbid)
+		}
+
+		mbid := "8f3471b5-7e6a-48da-86a9-c1c07a0f47ae"
+
+		It("handles a malformed request with status code", func() {
+			httpClient.Res = http.Response{
+				Body:       io.NopCloser(bytes.NewBufferString(`Bad request`)),
+				StatusCode: 400,
+			}
+			_, err := client.getSimilarRecordings(context.Background(), "1", 2)
+			Expect(err.Error()).To(Equal("ListenBrainz: HTTP Error, Status: (400)"))
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(getUrl("1")))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+		})
+
+		It("handles real data properly", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.labs.similar-recordings.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+			resp, err := client.getSimilarRecordings(context.Background(), mbid, 2)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(getUrl(mbid)))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+			Expect(resp).To(Equal([]recording{
+				{
+					MBID:        "12f65dca-de8f-43fe-a65d-f12a02aaadf3",
+					Name:        "Take On Me",
+					Artist:      "a‐ha",
+					ReleaseName: "Hunting High and Low",
+					ReleaseMBID: "4ec07fe8-e7c6-3106-a0aa-fdf92f13f7fc",
+					Score:       124,
+				},
+				{
+					MBID:        "80033c72-aa19-4ba8-9227-afb075fec46e",
+					Name:        "Wake Me Up Before You Go‐Go",
+					Artist:      "Wham!",
+					ReleaseName: "Make It Big",
+					ReleaseMBID: "c143d542-48dc-446b-b523-1762da721638",
+					Score:       65,
+				},
+			}))
+		})
+
+		It("truncates data when requested", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.labs.similar-recordings.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+			resp, err := client.getSimilarRecordings(context.Background(), mbid, 1)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(getUrl(mbid)))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+			Expect(resp).To(Equal([]recording{
+				{
+					MBID:        "12f65dca-de8f-43fe-a65d-f12a02aaadf3",
+					Name:        "Take On Me",
+					Artist:      "a‐ha",
+					ReleaseName: "Hunting High and Low",
+					ReleaseMBID: "4ec07fe8-e7c6-3106-a0aa-fdf92f13f7fc",
+					Score:       124,
+				},
+			}))
+		})
+
+		It("properly sorts by score and truncates duplicates", func() {
+			f, _ := os.Open("tests/fixtures/listenbrainz.labs.similar-recordings-real-out-of-order.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+			// There are actually 5 items. The dedup should happen FIRST
+			resp, err := client.getSimilarRecordings(context.Background(), mbid, 4)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(getUrl(mbid)))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+			Expect(resp).To(Equal([]recording{
+				{
+					MBID:        "12f65dca-de8f-43fe-a65d-f12a02aaadf3",
+					Name:        "Take On Me",
+					Artist:      "a‐ha",
+					ReleaseName: "Hunting High and Low",
+					ReleaseMBID: "4ec07fe8-e7c6-3106-a0aa-fdf92f13f7fc",
+					Score:       124,
+				},
+				{
+					MBID:        "e4b347be-ecb2-44ff-aaa8-3d4c517d7ea5",
+					Name:        "Everybody Wants to Rule the World",
+					Artist:      "Tears for Fears",
+					ReleaseName: "Songs From the Big Chair",
+					ReleaseMBID: "21f19b06-81f1-347a-add5-5d0c77696597",
+					Score:       68,
+				},
+				{
+					MBID:        "80033c72-aa19-4ba8-9227-afb075fec46e",
+					Name:        "Wake Me Up Before You Go‐Go",
+					Artist:      "Wham!",
+					ReleaseName: "Make It Big",
+					ReleaseMBID: "c143d542-48dc-446b-b523-1762da721638",
+					Score:       65,
+				},
+				{
+					MBID:        "ef4c6855-949e-4e22-b41e-8e0a2d372d5f",
+					Name:        "Tainted Love",
+					Artist:      "Soft Cell",
+					ReleaseName: "Non-Stop Erotic Cabaret",
+					ReleaseMBID: "1acaa870-6e0c-4b6e-9e91-fdec4e5ea4b1",
+					Score:       61,
+				},
+			}))
+		})
+
+		It("uses a different algorithm when configured", func() {
+			algorithm = "session_based_days_180_session_300_contribution_5_threshold_15_limit_50_skip_30"
+			conf.Server.ListenBrainz.TrackAlgorithm = algorithm
+
+			f, _ := os.Open("tests/fixtures/listenbrainz.labs.similar-recordings.json")
+			httpClient.Res = http.Response{Body: f, StatusCode: 200}
+			resp, err := client.getSimilarRecordings(context.Background(), mbid, 1)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(httpClient.SavedRequest.Method).To(Equal(http.MethodGet))
+			Expect(httpClient.SavedRequest.URL.String()).To(Equal(getUrl(mbid)))
+			Expect(httpClient.SavedRequest.Header.Get("Content-Type")).To(Equal("application/json; charset=UTF-8"))
+			Expect(resp).To(Equal([]recording{
+				{
+					MBID:        "12f65dca-de8f-43fe-a65d-f12a02aaadf3",
+					Name:        "Take On Me",
+					Artist:      "a‐ha",
+					ReleaseName: "Hunting High and Low",
+					ReleaseMBID: "4ec07fe8-e7c6-3106-a0aa-fdf92f13f7fc",
+					Score:       124,
+				},
+			}))
+		})
+	})
 })

adapters/spotify/client.go

@@ -73,7 +73,7 @@ func (c *client) authorize(ctx context.Context) (string, error) {
 	auth := c.id + ":" + c.secret
 	req.Header.Add("Authorization", "Basic "+base64.StdEncoding.EncodeToString([]byte(auth)))
 
-	response := map[string]interface{}{}
+	response := map[string]any{}
 	err := c.makeRequest(req, &response)
 	if err != nil {
 		return "", err
@@ -86,7 +86,7 @@ func (c *client) authorize(ctx context.Context) (string, error) {
 	return "", errors.New("invalid response")
 }
 
-func (c *client) makeRequest(req *http.Request, response interface{}) error {
+func (c *client) makeRequest(req *http.Request, response any) error {
 	log.Trace(req.Context(), fmt.Sprintf("Sending Spotify %s request", req.Method), "url", req.URL)
 	resp, err := c.hc.Do(req)
 	if err != nil {

cmd/wire_gen.go

@@ -19,6 +19,7 @@ import (
 	"github.com/navidrome/navidrome/core/metrics"
 	"github.com/navidrome/navidrome/core/playback"
 	"github.com/navidrome/navidrome/core/scrobbler"
+	"github.com/navidrome/navidrome/core/transcode"
 	"github.com/navidrome/navidrome/db"
 	"github.com/navidrome/navidrome/model"
 	"github.com/navidrome/navidrome/persistence"
@@ -102,7 +103,8 @@ func CreateSubsonicAPIRouter(ctx context.Context) *subsonic.Router {
 	modelScanner := scanner.New(ctx, dataStore, cacheWarmer, broker, playlists, metricsMetrics)
 	playTracker := scrobbler.GetPlayTracker(dataStore, broker, manager)
 	playbackServer := playback.GetInstance(dataStore)
-	router := subsonic.New(dataStore, artworkArtwork, mediaStreamer, archiver, players, provider, modelScanner, broker, playlists, playTracker, share, playbackServer, metricsMetrics)
+	decider := transcode.NewDecider(dataStore)
+	router := subsonic.New(dataStore, artworkArtwork, mediaStreamer, archiver, players, provider, modelScanner, broker, playlists, playTracker, share, playbackServer, metricsMetrics, decider)
 	return router
 }
 

conf/configuration.go

@@ -7,6 +7,7 @@ import (
 	"os"
 	"path/filepath"
 	"runtime"
+	"slices"
 	"strings"
 	"time"
 
@@ -194,8 +195,10 @@ type deezerOptions struct {
 }
 
 type listenBrainzOptions struct {
-	Enabled bool
-	BaseURL string
+	Enabled         bool
+	BaseURL         string
+	ArtistAlgorithm string
+	TrackAlgorithm  string
 }
 
 type httpHeaderOptions struct {
@@ -431,7 +434,7 @@ func mapDeprecatedOption(legacyName, newName string) {
 func parseIniFileConfiguration() {
 	cfgFile := viper.ConfigFileUsed()
 	if strings.ToLower(filepath.Ext(cfgFile)) == ".ini" {
-		var iniConfig map[string]interface{}
+		var iniConfig map[string]any
 		err := viper.Unmarshal(&iniConfig)
 		if err != nil {
 			_, _ = fmt.Fprintln(os.Stderr, "FATAL: Error parsing config:", err)
@@ -464,7 +467,7 @@ func disableExternalServices() {
 }
 
 func validatePlaylistsPath() error {
-	for _, path := range strings.Split(Server.PlaylistsPath, string(filepath.ListSeparator)) {
+	for path := range strings.SplitSeq(Server.PlaylistsPath, string(filepath.ListSeparator)) {
 		_, err := doublestar.Match(path, "")
 		if err != nil {
 			log.Error("Invalid PlaylistsPath", "path", path, err)
@@ -478,7 +481,7 @@ func validatePlaylistsPath() error {
 // It trims whitespace from each entry and ensures at least [DefaultInfoLanguage] is returned.
 func parseLanguages(lang string) []string {
 	var languages []string
-	for _, l := range strings.Split(lang, ",") {
+	for l := range strings.SplitSeq(lang, ",") {
 		l = strings.TrimSpace(l)
 		if l != "" {
 			languages = append(languages, l)
@@ -492,13 +495,7 @@ func parseLanguages(lang string) []string {
 
 func validatePurgeMissingOption() error {
 	allowedValues := []string{consts.PurgeMissingNever, consts.PurgeMissingAlways, consts.PurgeMissingFull}
-	valid := false
-	for _, v := range allowedValues {
-		if v == Server.Scanner.PurgeMissing {
-			valid = true
-			break
-		}
-	}
+	valid := slices.Contains(allowedValues, Server.Scanner.PurgeMissing)
 	if !valid {
 		err := fmt.Errorf("invalid Scanner.PurgeMissing value: '%s'. Must be one of: %v", Server.Scanner.PurgeMissing, allowedValues)
 		log.Error(err.Error())
@@ -656,7 +653,9 @@ func setViperDefaults() {
 	viper.SetDefault("deezer.enabled", true)
 	viper.SetDefault("deezer.language", consts.DefaultInfoLanguage)
 	viper.SetDefault("listenbrainz.enabled", true)
-	viper.SetDefault("listenbrainz.baseurl", "https://api.listenbrainz.org/1/")
+	viper.SetDefault("listenbrainz.baseurl", consts.DefaultListenBrainzBaseURL)
+	viper.SetDefault("listenbrainz.artistalgorithm", consts.DefaultListenBrainzArtistAlgorithm)
+	viper.SetDefault("listenbrainz.trackalgorithm", consts.DefaultListenBrainzTrackAlgorithm)
 	viper.SetDefault("enablescrobblehistory", true)
 	viper.SetDefault("httpheaders.frameoptions", "DENY")
 	viper.SetDefault("backup.path", "")

consts/consts.go

@@ -74,6 +74,10 @@ const (
 
 	DefaultHttpClientTimeOut = 10 * time.Second
 
+	DefaultListenBrainzBaseURL         = "https://api.listenbrainz.org/1/"
+	DefaultListenBrainzArtistAlgorithm = "session_based_days_9000_session_300_contribution_5_threshold_15_limit_50_skip_30"
+	DefaultListenBrainzTrackAlgorithm  = "session_based_days_9000_session_300_contribution_5_threshold_15_limit_50_skip_30"
+
 	DefaultScannerExtractor = "taglib"
 	DefaultWatcherWait      = 5 * time.Second
 	Zwsp                    = string('\u200b')
@@ -147,7 +151,13 @@ var (
 			Name:           "aac audio",
 			TargetFormat:   "aac",
 			DefaultBitRate: 256,
-			Command:        "ffmpeg -i %s -ss %t -map 0:a:0 -b:a %bk -v 0 -c:a aac -f adts -",
+			Command:        "ffmpeg -i %s -ss %t -map 0:a:0 -b:a %bk -v 0 -c:a aac -f ipod -movflags frag_keyframe+empty_moov -",
+		},
+		{
+			Name:           "flac audio",
+			TargetFormat:   "flac",
+			DefaultBitRate: 0,
+			Command:        "ffmpeg -i %s -ss %t -map 0:a:0 -v 0 -c:a flac -f flac -",
 		},
 	}
 )

core/agents/agents_test.go

@@ -365,7 +365,7 @@ var _ = Describe("Agents", func() {
 })
 
 type mockAgent struct {
-	Args []interface{}
+	Args []any
 	Err  error
 }
 
@@ -374,7 +374,7 @@ func (a *mockAgent) AgentName() string {
 }
 
 func (a *mockAgent) GetArtistMBID(_ context.Context, id string, name string) (string, error) {
-	a.Args = []interface{}{id, name}
+	a.Args = []any{id, name}
 	if a.Err != nil {
 		return "", a.Err
 	}
@@ -382,7 +382,7 @@ func (a *mockAgent) GetArtistMBID(_ context.Context, id string, name string) (st
 }
 
 func (a *mockAgent) GetArtistURL(_ context.Context, id, name, mbid string) (string, error) {
-	a.Args = []interface{}{id, name, mbid}
+	a.Args = []any{id, name, mbid}
 	if a.Err != nil {
 		return "", a.Err
 	}
@@ -390,7 +390,7 @@ func (a *mockAgent) GetArtistURL(_ context.Context, id, name, mbid string) (stri
 }
 
 func (a *mockAgent) GetArtistBiography(_ context.Context, id, name, mbid string) (string, error) {
-	a.Args = []interface{}{id, name, mbid}
+	a.Args = []any{id, name, mbid}
 	if a.Err != nil {
 		return "", a.Err
 	}
@@ -398,7 +398,7 @@ func (a *mockAgent) GetArtistBiography(_ context.Context, id, name, mbid string)
 }
 
 func (a *mockAgent) GetArtistImages(_ context.Context, id, name, mbid string) ([]ExternalImage, error) {
-	a.Args = []interface{}{id, name, mbid}
+	a.Args = []any{id, name, mbid}
 	if a.Err != nil {
 		return nil, a.Err
 	}
@@ -409,7 +409,7 @@ func (a *mockAgent) GetArtistImages(_ context.Context, id, name, mbid string) ([
 }
 
 func (a *mockAgent) GetSimilarArtists(_ context.Context, id, name, mbid string, limit int) ([]Artist, error) {
-	a.Args = []interface{}{id, name, mbid, limit}
+	a.Args = []any{id, name, mbid, limit}
 	if a.Err != nil {
 		return nil, a.Err
 	}
@@ -420,7 +420,7 @@ func (a *mockAgent) GetSimilarArtists(_ context.Context, id, name, mbid string,
 }
 
 func (a *mockAgent) GetArtistTopSongs(_ context.Context, id, artistName, mbid string, count int) ([]Song, error) {
-	a.Args = []interface{}{id, artistName, mbid, count}
+	a.Args = []any{id, artistName, mbid, count}
 	if a.Err != nil {
 		return nil, a.Err
 	}
@@ -431,7 +431,7 @@ func (a *mockAgent) GetArtistTopSongs(_ context.Context, id, artistName, mbid st
 }
 
 func (a *mockAgent) GetAlbumInfo(ctx context.Context, name, artist, mbid string) (*AlbumInfo, error) {
-	a.Args = []interface{}{name, artist, mbid}
+	a.Args = []any{name, artist, mbid}
 	if a.Err != nil {
 		return nil, a.Err
 	}
@@ -444,7 +444,7 @@ func (a *mockAgent) GetAlbumInfo(ctx context.Context, name, artist, mbid string)
 }
 
 func (a *mockAgent) GetSimilarSongsByTrack(_ context.Context, id, name, artist, mbid string, count int) ([]Song, error) {
-	a.Args = []interface{}{id, name, artist, mbid, count}
+	a.Args = []any{id, name, artist, mbid, count}
 	if a.Err != nil {
 		return nil, a.Err
 	}
@@ -455,7 +455,7 @@ func (a *mockAgent) GetSimilarSongsByTrack(_ context.Context, id, name, artist,
 }
 
 func (a *mockAgent) GetSimilarSongsByAlbum(_ context.Context, id, name, artist, mbid string, count int) ([]Song, error) {
-	a.Args = []interface{}{id, name, artist, mbid, count}
+	a.Args = []any{id, name, artist, mbid, count}
 	if a.Err != nil {
 		return nil, a.Err
 	}
@@ -466,7 +466,7 @@ func (a *mockAgent) GetSimilarSongsByAlbum(_ context.Context, id, name, artist,
 }
 
 func (a *mockAgent) GetSimilarSongsByArtist(_ context.Context, id, name, mbid string, count int) ([]Song, error) {
-	a.Args = []interface{}{id, name, mbid, count}
+	a.Args = []any{id, name, mbid, count}
 	if a.Err != nil {
 		return nil, a.Err
 	}
@@ -488,12 +488,12 @@ type testImageAgent struct {
 	Name   string
 	Images []ExternalImage
 	Err    error
-	Args   []interface{}
+	Args   []any
 }
 
 func (t *testImageAgent) AgentName() string { return t.Name }
 
 func (t *testImageAgent) GetArtistImages(_ context.Context, id, name, mbid string) ([]ExternalImage, error) {
-	t.Args = []interface{}{id, name, mbid}
+	t.Args = []any{id, name, mbid}
 	return t.Images, t.Err
 }

core/archiver.go

@@ -176,7 +176,7 @@ func (a *archiver) addFileToZip(ctx context.Context, z *zip.Writer, mf model.Med
 
 	var r io.ReadCloser
 	if format != "raw" && format != "" {
-		r, err = a.ms.DoStream(ctx, &mf, format, bitrate, 0)
+		r, err = a.ms.DoStream(ctx, &mf, StreamRequest{Format: format, BitRate: bitrate})
 	} else {
 		r, err = os.Open(path)
 	}

core/archiver_test.go

@@ -44,7 +44,7 @@ var _ = Describe("Archiver", func() {
 			}}).Return(mfs, nil)
 
 			ds.On("MediaFile", mock.Anything).Return(mfRepo)
-			ms.On("DoStream", mock.Anything, mock.Anything, "mp3", 128, 0).Return(io.NopCloser(strings.NewReader("test")), nil).Times(3)
+			ms.On("DoStream", mock.Anything, mock.Anything, "mp3", 128, 0, 0, 0, 0).Return(io.NopCloser(strings.NewReader("test")), nil).Times(3)
 
 			out := new(bytes.Buffer)
 			err := arch.ZipAlbum(context.Background(), "1", "mp3", 128, out)
@@ -73,7 +73,7 @@ var _ = Describe("Archiver", func() {
 			}}).Return(mfs, nil)
 
 			ds.On("MediaFile", mock.Anything).Return(mfRepo)
-			ms.On("DoStream", mock.Anything, mock.Anything, "mp3", 128, 0).Return(io.NopCloser(strings.NewReader("test")), nil).Times(2)
+			ms.On("DoStream", mock.Anything, mock.Anything, "mp3", 128, 0, 0, 0, 0).Return(io.NopCloser(strings.NewReader("test")), nil).Times(2)
 
 			out := new(bytes.Buffer)
 			err := arch.ZipArtist(context.Background(), "1", "mp3", 128, out)
@@ -104,7 +104,7 @@ var _ = Describe("Archiver", func() {
 			}
 
 			sh.On("Load", mock.Anything, "1").Return(share, nil)
-			ms.On("DoStream", mock.Anything, mock.Anything, "mp3", 128, 0).Return(io.NopCloser(strings.NewReader("test")), nil).Times(2)
+			ms.On("DoStream", mock.Anything, mock.Anything, "mp3", 128, 0, 0, 0, 0).Return(io.NopCloser(strings.NewReader("test")), nil).Times(2)
 
 			out := new(bytes.Buffer)
 			err := arch.ZipShare(context.Background(), "1", out)
@@ -136,7 +136,7 @@ var _ = Describe("Archiver", func() {
 			plRepo := &mockPlaylistRepository{}
 			plRepo.On("GetWithTracks", "1", true, false).Return(pls, nil)
 			ds.On("Playlist", mock.Anything).Return(plRepo)
-			ms.On("DoStream", mock.Anything, mock.Anything, "mp3", 128, 0).Return(io.NopCloser(strings.NewReader("test")), nil).Times(2)
+			ms.On("DoStream", mock.Anything, mock.Anything, "mp3", 128, 0, 0, 0, 0).Return(io.NopCloser(strings.NewReader("test")), nil).Times(2)
 
 			out := new(bytes.Buffer)
 			err := arch.ZipPlaylist(context.Background(), "1", "mp3", 128, out)
@@ -217,8 +217,8 @@ type mockMediaStreamer struct {
 	core.MediaStreamer
 }
 
-func (m *mockMediaStreamer) DoStream(ctx context.Context, mf *model.MediaFile, reqFormat string, reqBitRate int, reqOffset int) (*core.Stream, error) {
-	args := m.Called(ctx, mf, reqFormat, reqBitRate, reqOffset)
+func (m *mockMediaStreamer) DoStream(ctx context.Context, mf *model.MediaFile, req core.StreamRequest) (*core.Stream, error) {
+	args := m.Called(ctx, mf, req.Format, req.BitRate, req.SampleRate, req.BitDepth, req.Channels, req.Offset)
 	if args.Error(1) != nil {
 		return nil, args.Error(1)
 	}

core/artwork/cache_warmer_test.go

@@ -143,7 +143,7 @@ var _ = Describe("CacheWarmer", func() {
 
 		It("processes items in batches", func() {
 			cw := NewCacheWarmer(aw, fc).(*cacheWarmer)
-			for i := 0; i < 5; i++ {
+			for i := range 5 {
 				cw.PreCache(model.MustParseArtworkID(fmt.Sprintf("al-%d", i)))
 			}
 

core/artwork/reader_album.go

@@ -79,7 +79,7 @@ func (a *albumArtworkReader) Reader(ctx context.Context) (io.ReadCloser, string,
 
 func (a *albumArtworkReader) fromCoverArtPriority(ctx context.Context, ffmpeg ffmpeg.FFmpeg, priority string) []sourceFunc {
 	var ff []sourceFunc
-	for _, pattern := range strings.Split(strings.ToLower(priority), ",") {
+	for pattern := range strings.SplitSeq(strings.ToLower(priority), ",") {
 		pattern = strings.TrimSpace(pattern)
 		switch {
 		case pattern == "embedded":

core/artwork/reader_artist.go

@@ -99,7 +99,7 @@ func (a *artistReader) Reader(ctx context.Context) (io.ReadCloser, string, error
 
 func (a *artistReader) fromArtistArtPriority(ctx context.Context, priority string) []sourceFunc {
 	var ff []sourceFunc
-	for _, pattern := range strings.Split(strings.ToLower(priority), ",") {
+	for pattern := range strings.SplitSeq(strings.ToLower(priority), ",") {
 		pattern = strings.TrimSpace(pattern)
 		switch {
 		case pattern == "external":
@@ -116,7 +116,7 @@ func (a *artistReader) fromArtistArtPriority(ctx context.Context, priority strin
 func fromArtistFolder(ctx context.Context, artistFolder string, pattern string) sourceFunc {
 	return func() (io.ReadCloser, string, error) {
 		current := artistFolder
-		for i := 0; i < maxArtistFolderTraversalDepth; i++ {
+		for range maxArtistFolderTraversalDepth {
 			if reader, path, err := findImageInFolder(ctx, current, pattern); err == nil {
 				return reader, path, nil
 			}

core/auth/auth.go

@@ -4,6 +4,7 @@ import (
 	"cmp"
 	"context"
 	"crypto/sha256"
+	"maps"
 	"sync"
 	"time"
 
@@ -53,9 +54,7 @@ func createBaseClaims() map[string]any {
 
 func CreatePublicToken(claims map[string]any) (string, error) {
 	tokenClaims := createBaseClaims()
-	for k, v := range claims {
-		tokenClaims[k] = v
-	}
+	maps.Copy(tokenClaims, claims)
 	_, token, err := TokenAuth.Encode(tokenClaims)
 
 	return token, err
@@ -66,9 +65,7 @@ func CreateExpiringPublicToken(exp time.Time, claims map[string]any) (string, er
 	if !exp.IsZero() {
 		tokenClaims[jwt.ExpirationKey] = exp.UTC().Unix()
 	}
-	for k, v := range claims {
-		tokenClaims[k] = v
-	}
+	maps.Copy(tokenClaims, claims)
 	_, token, err := TokenAuth.Encode(tokenClaims)
 
 	return token, err
@@ -100,7 +97,7 @@ func TouchToken(token jwt.Token) (string, error) {
 	return newToken, err
 }
 
-func Validate(tokenStr string) (map[string]interface{}, error) {
+func Validate(tokenStr string) (map[string]any, error) {
 	token, err := jwtauth.VerifyToken(TokenAuth, tokenStr)
 	if err != nil {
 		return nil, err

core/auth/auth_test.go

@@ -45,7 +45,7 @@ var _ = Describe("Auth", func() {
 		})
 
 		It("returns the claims from a valid JWT token", func() {
-			claims := map[string]interface{}{}
+			claims := map[string]any{}
 			claims["iss"] = "issuer"
 			claims["iat"] = time.Now().Unix()
 			claims["exp"] = time.Now().Add(1 * time.Minute).Unix()
@@ -58,7 +58,7 @@ var _ = Describe("Auth", func() {
 		})
 
 		It("returns ErrExpired if the `exp` field is in the past", func() {
-			claims := map[string]interface{}{}
+			claims := map[string]any{}
 			claims["iss"] = "issuer"
 			claims["exp"] = time.Now().Add(-1 * time.Minute).Unix()
 			_, tokenStr, err := auth.TokenAuth.Encode(claims)
@@ -93,7 +93,7 @@ var _ = Describe("Auth", func() {
 	Describe("TouchToken", func() {
 		It("updates the expiration time", func() {
 			yesterday := time.Now().Add(-oneDay)
-			claims := map[string]interface{}{}
+			claims := map[string]any{}
 			claims["iss"] = "issuer"
 			claims["exp"] = yesterday.Unix()
 			token, _, err := auth.TokenAuth.Encode(claims)

core/external/extdata_helper_test.go

@@ -40,7 +40,7 @@ func (m *mockArtistRepo) Get(id string) (*model.Artist, error) {
 
 // GetAll implements model.ArtistRepository.
 func (m *mockArtistRepo) GetAll(options ...model.QueryOptions) (model.Artists, error) {
-	argsSlice := make([]interface{}, len(options))
+	argsSlice := make([]any, len(options))
 	for i, v := range options {
 		argsSlice[i] = v
 	}
@@ -99,7 +99,7 @@ func (m *mockMediaFileRepo) GetAllByTags(_ model.TagName, _ []string, options ..
 
 // GetAll implements model.MediaFileRepository.
 func (m *mockMediaFileRepo) GetAll(options ...model.QueryOptions) (model.MediaFiles, error) {
-	argsSlice := make([]interface{}, len(options))
+	argsSlice := make([]any, len(options))
 	for i, v := range options {
 		argsSlice[i] = v
 	}
@@ -152,7 +152,7 @@ func (m *mockAlbumRepo) Get(id string) (*model.Album, error) {
 
 // GetAll implements model.AlbumRepository.
 func (m *mockAlbumRepo) GetAll(options ...model.QueryOptions) (model.Albums, error) {
-	argsSlice := make([]interface{}, len(options))
+	argsSlice := make([]any, len(options))
 	for i, v := range options {
 		argsSlice[i] = v
 	}

core/external/provider.go

@@ -93,7 +93,7 @@ func NewProvider(ds model.DataStore, agents Agents) Provider {
 }
 
 func (e *provider) getAlbum(ctx context.Context, id string) (auxAlbum, error) {
-	var entity interface{}
+	var entity any
 	entity, err := model.GetEntityByID(ctx, e.ds, id)
 	if err != nil {
 		return auxAlbum{}, err
@@ -187,7 +187,7 @@ func (e *provider) populateAlbumInfo(ctx context.Context, album auxAlbum) (auxAl
 }
 
 func (e *provider) getArtist(ctx context.Context, id string) (auxArtist, error) {
-	var entity interface{}
+	var entity any
 	entity, err := model.GetEntityByID(ctx, e.ds, id)
 	if err != nil {
 		return auxArtist{}, err

core/ffmpeg/ffmpeg.go

@@ -12,11 +12,24 @@ import (
 	"sync"
 
 	"github.com/navidrome/navidrome/conf"
+	"github.com/navidrome/navidrome/consts"
 	"github.com/navidrome/navidrome/log"
 )
 
+// TranscodeOptions contains all parameters for a transcoding operation.
+type TranscodeOptions struct {
+	Command    string // DB command template (used to detect custom vs default)
+	Format     string // Target format (mp3, opus, aac, flac)
+	FilePath   string
+	BitRate    int // kbps, 0 = codec default
+	SampleRate int // 0 = no constraint
+	Channels   int // 0 = no constraint
+	BitDepth   int // 0 = no constraint; valid values: 16, 24, 32
+	Offset     int // seconds
+}
+
 type FFmpeg interface {
-	Transcode(ctx context.Context, command, path string, maxBitRate, offset int) (io.ReadCloser, error)
+	Transcode(ctx context.Context, opts TranscodeOptions) (io.ReadCloser, error)
 	ExtractImage(ctx context.Context, path string) (io.ReadCloser, error)
 	Probe(ctx context.Context, files []string) (string, error)
 	CmdPath() (string, error)
@@ -35,15 +48,19 @@ const (
 
 type ffmpeg struct{}
 
-func (e *ffmpeg) Transcode(ctx context.Context, command, path string, maxBitRate, offset int) (io.ReadCloser, error) {
+func (e *ffmpeg) Transcode(ctx context.Context, opts TranscodeOptions) (io.ReadCloser, error) {
 	if _, err := ffmpegCmd(); err != nil {
 		return nil, err
 	}
-	// First make sure the file exists
-	if err := fileExists(path); err != nil {
+	if err := fileExists(opts.FilePath); err != nil {
 		return nil, err
 	}
-	args := createFFmpegCommand(command, path, maxBitRate, offset)
+	var args []string
+	if isDefaultCommand(opts.Format, opts.Command) {
+		args = buildDynamicArgs(opts)
+	} else {
+		args = buildTemplateArgs(opts)
+	}
 	return e.start(ctx, args)
 }
 
@@ -51,7 +68,6 @@ func (e *ffmpeg) ExtractImage(ctx context.Context, path string) (io.ReadCloser,
 	if _, err := ffmpegCmd(); err != nil {
 		return nil, err
 	}
-	// First make sure the file exists
 	if err := fileExists(path); err != nil {
 		return nil, err
 	}
@@ -156,6 +172,139 @@ func (j *ffCmd) wait() {
 	_ = j.out.Close()
 }
 
+// formatCodecMap maps target format to ffmpeg codec flag.
+var formatCodecMap = map[string]string{
+	"mp3":  "libmp3lame",
+	"opus": "libopus",
+	"aac":  "aac",
+	"flac": "flac",
+}
+
+// formatOutputMap maps target format to ffmpeg output format flag (-f).
+var formatOutputMap = map[string]string{
+	"mp3":  "mp3",
+	"opus": "opus",
+	"aac":  "ipod",
+	"flac": "flac",
+}
+
+// defaultCommands is used to detect whether a user has customized their transcoding command.
+var defaultCommands = func() map[string]string {
+	m := make(map[string]string, len(consts.DefaultTranscodings))
+	for _, t := range consts.DefaultTranscodings {
+		m[t.TargetFormat] = t.Command
+	}
+	return m
+}()
+
+// isDefaultCommand returns true if the command matches the known default for this format.
+func isDefaultCommand(format, command string) bool {
+	return defaultCommands[format] == command
+}
+
+// buildDynamicArgs programmatically constructs ffmpeg arguments for known formats,
+// including all transcoding parameters (bitrate, sample rate, channels).
+func buildDynamicArgs(opts TranscodeOptions) []string {
+	cmdPath, _ := ffmpegCmd()
+	args := []string{cmdPath, "-i", opts.FilePath}
+
+	if opts.Offset > 0 {
+		args = append(args, "-ss", strconv.Itoa(opts.Offset))
+	}
+
+	args = append(args, "-map", "0:a:0")
+
+	if codec, ok := formatCodecMap[opts.Format]; ok {
+		args = append(args, "-c:a", codec)
+	}
+
+	if opts.BitRate > 0 {
+		args = append(args, "-b:a", strconv.Itoa(opts.BitRate)+"k")
+	}
+	if opts.SampleRate > 0 {
+		args = append(args, "-ar", strconv.Itoa(opts.SampleRate))
+	}
+	if opts.Channels > 0 {
+		args = append(args, "-ac", strconv.Itoa(opts.Channels))
+	}
+	// Only pass -sample_fmt for lossless output formats where bit depth matters.
+	// Lossy codecs (mp3, aac, opus) handle sample format conversion internally,
+	// and passing interleaved formats like "s16" causes silent failures.
+	if opts.BitDepth >= 16 && isLosslessOutputFormat(opts.Format) {
+		args = append(args, "-sample_fmt", bitDepthToSampleFmt(opts.BitDepth))
+	}
+
+	args = append(args, "-v", "0")
+
+	if outputFmt, ok := formatOutputMap[opts.Format]; ok {
+		args = append(args, "-f", outputFmt)
+	}
+
+	// For AAC in MP4 container, enable fragmented MP4 for pipe-safe streaming
+	if opts.Format == "aac" {
+		args = append(args, "-movflags", "frag_keyframe+empty_moov")
+	}
+
+	args = append(args, "-")
+	return args
+}
+
+// buildTemplateArgs handles user-customized command templates, with dynamic injection
+// of sample rate and channels when the template doesn't already include them.
+func buildTemplateArgs(opts TranscodeOptions) []string {
+	args := createFFmpegCommand(opts.Command, opts.FilePath, opts.BitRate, opts.Offset)
+
+	// Dynamically inject -ar, -ac, and -sample_fmt for custom templates that don't include them
+	if opts.SampleRate > 0 {
+		args = injectBeforeOutput(args, "-ar", strconv.Itoa(opts.SampleRate))
+	}
+	if opts.Channels > 0 {
+		args = injectBeforeOutput(args, "-ac", strconv.Itoa(opts.Channels))
+	}
+	if opts.BitDepth >= 16 && isLosslessOutputFormat(opts.Format) {
+		args = injectBeforeOutput(args, "-sample_fmt", bitDepthToSampleFmt(opts.BitDepth))
+	}
+	return args
+}
+
+// injectBeforeOutput inserts a flag and value before the trailing "-" (stdout output).
+func injectBeforeOutput(args []string, flag, value string) []string {
+	if len(args) > 0 && args[len(args)-1] == "-" {
+		result := make([]string, 0, len(args)+2)
+		result = append(result, args[:len(args)-1]...)
+		result = append(result, flag, value, "-")
+		return result
+	}
+	return append(args, flag, value)
+}
+
+// isLosslessOutputFormat returns true if the format is a lossless audio format
+// where preserving bit depth via -sample_fmt is meaningful.
+// Note: this covers only formats ffmpeg can produce as output. For the full set of
+// lossless formats used in transcoding decisions, see core/transcode/codec.go:isLosslessFormat.
+func isLosslessOutputFormat(format string) bool {
+	switch strings.ToLower(format) {
+	case "flac", "alac", "wav", "aiff":
+		return true
+	}
+	return false
+}
+
+// bitDepthToSampleFmt converts a bit depth value to the ffmpeg sample_fmt string.
+// FLAC only supports s16 and s32; for 24-bit sources, s32 is the correct format
+// (ffmpeg packs 24-bit samples into 32-bit containers).
+func bitDepthToSampleFmt(bitDepth int) string {
+	switch bitDepth {
+	case 16:
+		return "s16"
+	case 32:
+		return "s32"
+	default:
+		// 24-bit and other depths: use s32 (the next valid container size)
+		return "s32"
+	}
+}
+
 // Path will always be an absolute path
 func createFFmpegCommand(cmd, path string, maxBitRate, offset int) []string {
 	var args []string

core/ffmpeg/ffmpeg_test.go

@@ -2,19 +2,27 @@ package ffmpeg
 
 import (
 	"context"
+	"os"
+	"path/filepath"
 	"runtime"
 	sync "sync"
 	"testing"
 	"time"
 
+	"github.com/navidrome/navidrome/conf"
 	"github.com/navidrome/navidrome/log"
-	"github.com/navidrome/navidrome/tests"
 	. "github.com/onsi/ginkgo/v2"
 	. "github.com/onsi/gomega"
 )
 
 func TestFFmpeg(t *testing.T) {
-	tests.Init(t, false)
+	// Inline test init to avoid import cycle with tests package
+	//nolint:dogsled
+	_, file, _, _ := runtime.Caller(0)
+	appPath, _ := filepath.Abs(filepath.Join(filepath.Dir(file), "..", ".."))
+	confPath := filepath.Join(appPath, "tests", "navidrome-test.toml")
+	_ = os.Chdir(appPath)
+	conf.LoadFromFile(confPath)
 	log.SetLevel(log.LevelFatal)
 	RegisterFailHandler(Fail)
 	RunSpecs(t, "FFmpeg Suite")
@@ -70,6 +78,286 @@ var _ = Describe("ffmpeg", func() {
 		})
 	})
 
+	Describe("isDefaultCommand", func() {
+		It("returns true for known default mp3 command", func() {
+			Expect(isDefaultCommand("mp3", "ffmpeg -i %s -ss %t -map 0:a:0 -b:a %bk -v 0 -f mp3 -")).To(BeTrue())
+		})
+		It("returns true for known default opus command", func() {
+			Expect(isDefaultCommand("opus", "ffmpeg -i %s -ss %t -map 0:a:0 -b:a %bk -v 0 -c:a libopus -f opus -")).To(BeTrue())
+		})
+		It("returns true for known default aac command", func() {
+			Expect(isDefaultCommand("aac", "ffmpeg -i %s -ss %t -map 0:a:0 -b:a %bk -v 0 -c:a aac -f ipod -movflags frag_keyframe+empty_moov -")).To(BeTrue())
+		})
+		It("returns true for known default flac command", func() {
+			Expect(isDefaultCommand("flac", "ffmpeg -i %s -ss %t -map 0:a:0 -v 0 -c:a flac -f flac -")).To(BeTrue())
+		})
+		It("returns false for a custom command", func() {
+			Expect(isDefaultCommand("mp3", "ffmpeg -i %s -b:a %bk -custom-flag -f mp3 -")).To(BeFalse())
+		})
+		It("returns false for unknown format", func() {
+			Expect(isDefaultCommand("wav", "ffmpeg -i %s -f wav -")).To(BeFalse())
+		})
+	})
+
+	Describe("buildDynamicArgs", func() {
+		It("builds mp3 args with bitrate, samplerate, and channels", func() {
+			args := buildDynamicArgs(TranscodeOptions{
+				Format:     "mp3",
+				FilePath:   "/music/file.flac",
+				BitRate:    256,
+				SampleRate: 48000,
+				Channels:   2,
+			})
+			Expect(args).To(Equal([]string{
+				"ffmpeg", "-i", "/music/file.flac",
+				"-map", "0:a:0",
+				"-c:a", "libmp3lame",
+				"-b:a", "256k",
+				"-ar", "48000",
+				"-ac", "2",
+				"-v", "0",
+				"-f", "mp3",
+				"-",
+			}))
+		})
+
+		It("builds flac args without bitrate", func() {
+			args := buildDynamicArgs(TranscodeOptions{
+				Format:     "flac",
+				FilePath:   "/music/file.dsf",
+				SampleRate: 48000,
+			})
+			Expect(args).To(Equal([]string{
+				"ffmpeg", "-i", "/music/file.dsf",
+				"-map", "0:a:0",
+				"-c:a", "flac",
+				"-ar", "48000",
+				"-v", "0",
+				"-f", "flac",
+				"-",
+			}))
+		})
+
+		It("builds opus args with bitrate only", func() {
+			args := buildDynamicArgs(TranscodeOptions{
+				Format:   "opus",
+				FilePath: "/music/file.flac",
+				BitRate:  128,
+			})
+			Expect(args).To(Equal([]string{
+				"ffmpeg", "-i", "/music/file.flac",
+				"-map", "0:a:0",
+				"-c:a", "libopus",
+				"-b:a", "128k",
+				"-v", "0",
+				"-f", "opus",
+				"-",
+			}))
+		})
+
+		It("includes offset when specified", func() {
+			args := buildDynamicArgs(TranscodeOptions{
+				Format:   "mp3",
+				FilePath: "/music/file.mp3",
+				BitRate:  192,
+				Offset:   30,
+			})
+			Expect(args).To(Equal([]string{
+				"ffmpeg", "-i", "/music/file.mp3",
+				"-ss", "30",
+				"-map", "0:a:0",
+				"-c:a", "libmp3lame",
+				"-b:a", "192k",
+				"-v", "0",
+				"-f", "mp3",
+				"-",
+			}))
+		})
+
+		It("builds aac args with fragmented MP4 container", func() {
+			args := buildDynamicArgs(TranscodeOptions{
+				Format:   "aac",
+				FilePath: "/music/file.flac",
+				BitRate:  256,
+			})
+			Expect(args).To(Equal([]string{
+				"ffmpeg", "-i", "/music/file.flac",
+				"-map", "0:a:0",
+				"-c:a", "aac",
+				"-b:a", "256k",
+				"-v", "0",
+				"-f", "ipod",
+				"-movflags", "frag_keyframe+empty_moov",
+				"-",
+			}))
+		})
+
+		It("builds flac args with bit depth", func() {
+			args := buildDynamicArgs(TranscodeOptions{
+				Format:   "flac",
+				FilePath: "/music/file.dsf",
+				BitDepth: 24,
+			})
+			Expect(args).To(Equal([]string{
+				"ffmpeg", "-i", "/music/file.dsf",
+				"-map", "0:a:0",
+				"-c:a", "flac",
+				"-sample_fmt", "s32",
+				"-v", "0",
+				"-f", "flac",
+				"-",
+			}))
+		})
+
+		It("omits -sample_fmt when bit depth is 0", func() {
+			args := buildDynamicArgs(TranscodeOptions{
+				Format:   "flac",
+				FilePath: "/music/file.flac",
+				BitDepth: 0,
+			})
+			Expect(args).ToNot(ContainElement("-sample_fmt"))
+		})
+
+		It("omits -sample_fmt when bit depth is too low (DSD)", func() {
+			args := buildDynamicArgs(TranscodeOptions{
+				Format:   "flac",
+				FilePath: "/music/file.dsf",
+				BitDepth: 1,
+			})
+			Expect(args).ToNot(ContainElement("-sample_fmt"))
+		})
+
+		It("omits -sample_fmt for mp3 even when bit depth >= 16", func() {
+			args := buildDynamicArgs(TranscodeOptions{
+				Format:   "mp3",
+				FilePath: "/music/file.flac",
+				BitRate:  256,
+				BitDepth: 16,
+			})
+			Expect(args).ToNot(ContainElement("-sample_fmt"))
+		})
+
+		It("omits -sample_fmt for aac even when bit depth >= 16", func() {
+			args := buildDynamicArgs(TranscodeOptions{
+				Format:   "aac",
+				FilePath: "/music/file.flac",
+				BitRate:  256,
+				BitDepth: 16,
+			})
+			Expect(args).ToNot(ContainElement("-sample_fmt"))
+		})
+
+		It("omits -sample_fmt for opus even when bit depth >= 16", func() {
+			args := buildDynamicArgs(TranscodeOptions{
+				Format:   "opus",
+				FilePath: "/music/file.flac",
+				BitRate:  128,
+				BitDepth: 16,
+			})
+			Expect(args).ToNot(ContainElement("-sample_fmt"))
+		})
+	})
+
+	Describe("bitDepthToSampleFmt", func() {
+		It("converts 16-bit", func() {
+			Expect(bitDepthToSampleFmt(16)).To(Equal("s16"))
+		})
+		It("converts 24-bit to s32 (FLAC only supports s16/s32)", func() {
+			Expect(bitDepthToSampleFmt(24)).To(Equal("s32"))
+		})
+		It("converts 32-bit", func() {
+			Expect(bitDepthToSampleFmt(32)).To(Equal("s32"))
+		})
+	})
+
+	Describe("buildTemplateArgs", func() {
+		It("injects -ar and -ac into custom template", func() {
+			args := buildTemplateArgs(TranscodeOptions{
+				Command:    "ffmpeg -i %s -b:a %bk -v 0 -f mp3 -",
+				FilePath:   "/music/file.flac",
+				BitRate:    192,
+				SampleRate: 44100,
+				Channels:   2,
+			})
+			Expect(args).To(Equal([]string{
+				"ffmpeg", "-i", "/music/file.flac",
+				"-b:a", "192k", "-v", "0", "-f", "mp3",
+				"-ar", "44100", "-ac", "2",
+				"-",
+			}))
+		})
+
+		It("injects only -ar when channels is 0", func() {
+			args := buildTemplateArgs(TranscodeOptions{
+				Command:    "ffmpeg -i %s -b:a %bk -v 0 -f mp3 -",
+				FilePath:   "/music/file.flac",
+				BitRate:    192,
+				SampleRate: 48000,
+			})
+			Expect(args).To(Equal([]string{
+				"ffmpeg", "-i", "/music/file.flac",
+				"-b:a", "192k", "-v", "0", "-f", "mp3",
+				"-ar", "48000",
+				"-",
+			}))
+		})
+
+		It("does not inject anything when sample rate and channels are 0", func() {
+			args := buildTemplateArgs(TranscodeOptions{
+				Command:  "ffmpeg -i %s -b:a %bk -v 0 -f mp3 -",
+				FilePath: "/music/file.flac",
+				BitRate:  192,
+			})
+			Expect(args).To(Equal([]string{
+				"ffmpeg", "-i", "/music/file.flac",
+				"-b:a", "192k", "-v", "0", "-f", "mp3",
+				"-",
+			}))
+		})
+
+		It("injects -sample_fmt for lossless output format with bit depth", func() {
+			args := buildTemplateArgs(TranscodeOptions{
+				Command:  "ffmpeg -i %s -v 0 -c:a flac -f flac -",
+				Format:   "flac",
+				FilePath: "/music/file.dsf",
+				BitDepth: 24,
+			})
+			Expect(args).To(Equal([]string{
+				"ffmpeg", "-i", "/music/file.dsf",
+				"-v", "0", "-c:a", "flac", "-f", "flac",
+				"-sample_fmt", "s32",
+				"-",
+			}))
+		})
+
+		It("does not inject -sample_fmt for lossy output format even with bit depth", func() {
+			args := buildTemplateArgs(TranscodeOptions{
+				Command:  "ffmpeg -i %s -b:a %bk -v 0 -f mp3 -",
+				Format:   "mp3",
+				FilePath: "/music/file.flac",
+				BitRate:  192,
+				BitDepth: 16,
+			})
+			Expect(args).To(Equal([]string{
+				"ffmpeg", "-i", "/music/file.flac",
+				"-b:a", "192k", "-v", "0", "-f", "mp3",
+				"-",
+			}))
+		})
+	})
+
+	Describe("injectBeforeOutput", func() {
+		It("inserts flag before trailing dash", func() {
+			args := injectBeforeOutput([]string{"ffmpeg", "-i", "file.mp3", "-f", "mp3", "-"}, "-ar", "48000")
+			Expect(args).To(Equal([]string{"ffmpeg", "-i", "file.mp3", "-f", "mp3", "-ar", "48000", "-"}))
+		})
+
+		It("appends when no trailing dash", func() {
+			args := injectBeforeOutput([]string{"ffmpeg", "-i", "file.mp3"}, "-ar", "48000")
+			Expect(args).To(Equal([]string{"ffmpeg", "-i", "file.mp3", "-ar", "48000"}))
+		})
+	})
+
 	Describe("FFmpeg", func() {
 		Context("when FFmpeg is available", func() {
 			var ff FFmpeg
@@ -93,7 +381,12 @@ var _ = Describe("ffmpeg", func() {
 				command := "ffmpeg -f lavfi -i sine=frequency=1000:duration=0 -f mp3 -"
 
 				// The input file is not used here, but we need to provide a valid path to the Transcode function
-				stream, err := ff.Transcode(ctx, command, "tests/fixtures/test.mp3", 128, 0)
+				stream, err := ff.Transcode(ctx, TranscodeOptions{
+					Command:  command,
+					Format:   "mp3",
+					FilePath: "tests/fixtures/test.mp3",
+					BitRate:  128,
+				})
 				Expect(err).ToNot(HaveOccurred())
 				defer stream.Close()
 
@@ -115,7 +408,12 @@ var _ = Describe("ffmpeg", func() {
 				cancel() // Cancel immediately
 
 				// This should fail immediately
-				_, err := ff.Transcode(ctx, "ffmpeg -i %s -f mp3 -", "tests/fixtures/test.mp3", 128, 0)
+				_, err := ff.Transcode(ctx, TranscodeOptions{
+					Command:  "ffmpeg -i %s -f mp3 -",
+					Format:   "mp3",
+					FilePath: "tests/fixtures/test.mp3",
+					BitRate:  128,
+				})
 				Expect(err).To(MatchError(context.Canceled))
 			})
 		})
@@ -142,7 +440,10 @@ var _ = Describe("ffmpeg", func() {
 				defer cancel()
 
 				// Start a process that will run for a while
-				stream, err := ff.Transcode(ctx, longRunningCmd, "tests/fixtures/test.mp3", 0, 0)
+				stream, err := ff.Transcode(ctx, TranscodeOptions{
+					Command:  longRunningCmd,
+					FilePath: "tests/fixtures/test.mp3",
+				})
 				Expect(err).ToNot(HaveOccurred())
 				defer stream.Close()
 

core/library.go

@@ -159,7 +159,7 @@ type libraryRepositoryWrapper struct {
 	pluginManager PluginUnloader
 }
 
-func (r *libraryRepositoryWrapper) Save(entity interface{}) (string, error) {
+func (r *libraryRepositoryWrapper) Save(entity any) (string, error) {
 	lib := entity.(*model.Library)
 	if err := r.validateLibrary(lib); err != nil {
 		return "", err
@@ -191,7 +191,7 @@ func (r *libraryRepositoryWrapper) Save(entity interface{}) (string, error) {
 	return strconv.Itoa(lib.ID), nil
 }
 
-func (r *libraryRepositoryWrapper) Update(id string, entity interface{}, _ ...string) error {
+func (r *libraryRepositoryWrapper) Update(id string, entity any, _ ...string) error {
 	lib := entity.(*model.Library)
 	libID, err := strconv.Atoi(id)
 	if err != nil {

core/maintenance.go

@@ -196,9 +196,7 @@ func (s *maintenanceService) getAffectedAlbumIDs(ctx context.Context, ids []stri
 // refreshStatsAsync refreshes artist and album statistics in background goroutines
 func (s *maintenanceService) refreshStatsAsync(ctx context.Context, affectedAlbumIDs []string) {
 	// Refresh artist stats in background
-	s.wg.Add(1)
-	go func() {
-		defer s.wg.Done()
+	s.wg.Go(func() {
 		bgCtx := request.AddValues(context.Background(), ctx)
 		if _, err := s.ds.Artist(bgCtx).RefreshStats(true); err != nil {
 			log.Error(bgCtx, "Error refreshing artist stats after deleting missing files", err)
@@ -214,7 +212,7 @@ func (s *maintenanceService) refreshStatsAsync(ctx context.Context, affectedAlbu
 				log.Debug(bgCtx, "Successfully refreshed album stats after deleting missing files", "count", len(affectedAlbumIDs))
 			}
 		}
-	}()
+	})
 }
 
 // Wait waits for all background goroutines to complete.

core/media_streamer.go

@@ -18,9 +18,20 @@ import (
 	"github.com/navidrome/navidrome/utils/cache"
 )
 
+// StreamRequest contains all parameters for creating a media stream.
+type StreamRequest struct {
+	ID         string
+	Format     string
+	BitRate    int // kbps
+	SampleRate int
+	BitDepth   int
+	Channels   int
+	Offset     int // seconds
+}
+
 type MediaStreamer interface {
-	NewStream(ctx context.Context, id string, reqFormat string, reqBitRate int, offset int) (*Stream, error)
-	DoStream(ctx context.Context, mf *model.MediaFile, reqFormat string, reqBitRate int, reqOffset int) (*Stream, error)
+	NewStream(ctx context.Context, req StreamRequest) (*Stream, error)
+	DoStream(ctx context.Context, mf *model.MediaFile, req StreamRequest) (*Stream, error)
 }
 
 type TranscodingCache cache.FileCache
@@ -36,28 +47,31 @@ type mediaStreamer struct {
 }
 
 type streamJob struct {
-	ms       *mediaStreamer
-	mf       *model.MediaFile
-	filePath string
-	format   string
-	bitRate  int
-	offset   int
+	ms         *mediaStreamer
+	mf         *model.MediaFile
+	filePath   string
+	format     string
+	bitRate    int
+	sampleRate int
+	bitDepth   int
+	channels   int
+	offset     int
 }
 
 func (j *streamJob) Key() string {
-	return fmt.Sprintf("%s.%s.%d.%s.%d", j.mf.ID, j.mf.UpdatedAt.Format(time.RFC3339Nano), j.bitRate, j.format, j.offset)
+	return fmt.Sprintf("%s.%s.%d.%d.%d.%d.%s.%d", j.mf.ID, j.mf.UpdatedAt.Format(time.RFC3339Nano), j.bitRate, j.sampleRate, j.bitDepth, j.channels, j.format, j.offset)
 }
 
-func (ms *mediaStreamer) NewStream(ctx context.Context, id string, reqFormat string, reqBitRate int, reqOffset int) (*Stream, error) {
-	mf, err := ms.ds.MediaFile(ctx).Get(id)
+func (ms *mediaStreamer) NewStream(ctx context.Context, req StreamRequest) (*Stream, error) {
+	mf, err := ms.ds.MediaFile(ctx).Get(req.ID)
 	if err != nil {
 		return nil, err
 	}
 
-	return ms.DoStream(ctx, mf, reqFormat, reqBitRate, reqOffset)
+	return ms.DoStream(ctx, mf, req)
 }
 
-func (ms *mediaStreamer) DoStream(ctx context.Context, mf *model.MediaFile, reqFormat string, reqBitRate int, reqOffset int) (*Stream, error) {
+func (ms *mediaStreamer) DoStream(ctx context.Context, mf *model.MediaFile, req StreamRequest) (*Stream, error) {
 	var format string
 	var bitRate int
 	var cached bool
@@ -67,13 +81,13 @@ func (ms *mediaStreamer) DoStream(ctx context.Context, mf *model.MediaFile, reqF
 			"originalFormat", mf.Suffix, "originalBitRate", mf.BitRate)
 	}()
 
-	format, bitRate = selectTranscodingOptions(ctx, ms.ds, mf, reqFormat, reqBitRate)
+	format, bitRate = selectTranscodingOptions(ctx, ms.ds, mf, req.Format, req.BitRate, req.SampleRate)
 	s := &Stream{ctx: ctx, mf: mf, format: format, bitRate: bitRate}
 	filePath := mf.AbsolutePath()
 
 	if format == "raw" {
 		log.Debug(ctx, "Streaming RAW file", "id", mf.ID, "path", filePath,
-			"requestBitrate", reqBitRate, "requestFormat", reqFormat, "requestOffset", reqOffset,
+			"requestBitrate", req.BitRate, "requestFormat", req.Format, "requestOffset", req.Offset,
 			"originalBitrate", mf.BitRate, "originalFormat", mf.Suffix,
 			"selectedBitrate", bitRate, "selectedFormat", format)
 		f, err := os.Open(filePath)
@@ -87,12 +101,15 @@ func (ms *mediaStreamer) DoStream(ctx context.Context, mf *model.MediaFile, reqF
 	}
 
 	job := &streamJob{
-		ms:       ms,
-		mf:       mf,
-		filePath: filePath,
-		format:   format,
-		bitRate:  bitRate,
-		offset:   reqOffset,
+		ms:         ms,
+		mf:         mf,
+		filePath:   filePath,
+		format:     format,
+		bitRate:    bitRate,
+		sampleRate: req.SampleRate,
+		bitDepth:   req.BitDepth,
+		channels:   req.Channels,
+		offset:     req.Offset,
 	}
 	r, err := ms.cache.Get(ctx, job)
 	if err != nil {
@@ -105,7 +122,7 @@ func (ms *mediaStreamer) DoStream(ctx context.Context, mf *model.MediaFile, reqF
 	s.Seeker = r.Seeker
 
 	log.Debug(ctx, "Streaming TRANSCODED file", "id", mf.ID, "path", filePath,
-		"requestBitrate", reqBitRate, "requestFormat", reqFormat, "requestOffset", reqOffset,
+		"requestBitrate", req.BitRate, "requestFormat", req.Format, "requestOffset", req.Offset,
 		"originalBitrate", mf.BitRate, "originalFormat", mf.Suffix,
 		"selectedBitrate", bitRate, "selectedFormat", format, "cached", cached, "seekable", s.Seekable())
 
@@ -131,12 +148,13 @@ func (s *Stream) EstimatedContentLength() int {
 }
 
 // TODO This function deserves some love (refactoring)
-func selectTranscodingOptions(ctx context.Context, ds model.DataStore, mf *model.MediaFile, reqFormat string, reqBitRate int) (format string, bitRate int) {
+func selectTranscodingOptions(ctx context.Context, ds model.DataStore, mf *model.MediaFile, reqFormat string, reqBitRate int, reqSampleRate int) (format string, bitRate int) {
 	format = "raw"
 	if reqFormat == "raw" {
 		return format, 0
 	}
-	if reqFormat == mf.Suffix && reqBitRate == 0 {
+	needsResample := reqSampleRate > 0 && reqSampleRate < mf.SampleRate
+	if reqFormat == mf.Suffix && reqBitRate == 0 && !needsResample {
 		bitRate = mf.BitRate
 		return format, bitRate
 	}
@@ -175,7 +193,7 @@ func selectTranscodingOptions(ctx context.Context, ds model.DataStore, mf *model
 			bitRate = t.DefaultBitRate
 		}
 	}
-	if format == mf.Suffix && bitRate >= mf.BitRate {
+	if format == mf.Suffix && bitRate >= mf.BitRate && !needsResample {
 		format = "raw"
 		bitRate = 0
 	}
@@ -217,7 +235,16 @@ func NewTranscodingCache() TranscodingCache {
 				transcodingCtx = request.AddValues(context.Background(), ctx)
 			}
 
-			out, err := job.ms.transcoder.Transcode(transcodingCtx, t.Command, job.filePath, job.bitRate, job.offset)
+			out, err := job.ms.transcoder.Transcode(transcodingCtx, ffmpeg.TranscodeOptions{
+				Command:    t.Command,
+				Format:     job.format,
+				FilePath:   job.filePath,
+				BitRate:    job.bitRate,
+				SampleRate: job.sampleRate,
+				BitDepth:   job.bitDepth,
+				Channels:   job.channels,
+				Offset:     job.offset,
+			})
 			if err != nil {
 				log.Error(ctx, "Error starting transcoder", "id", job.mf.ID, err)
 				return nil, os.ErrInvalid

core/media_streamer_Internal_test.go

@@ -26,42 +26,64 @@ var _ = Describe("MediaStreamer", func() {
 			It("returns raw if raw is requested", func() {
 				mf.Suffix = "flac"
 				mf.BitRate = 1000
-				format, _ := selectTranscodingOptions(ctx, ds, mf, "raw", 0)
+				format, _ := selectTranscodingOptions(ctx, ds, mf, "raw", 0, 0)
 				Expect(format).To(Equal("raw"))
 			})
 			It("returns raw if a transcoder does not exists", func() {
 				mf.Suffix = "flac"
 				mf.BitRate = 1000
-				format, _ := selectTranscodingOptions(ctx, ds, mf, "m4a", 0)
+				format, _ := selectTranscodingOptions(ctx, ds, mf, "m4a", 0, 0)
 				Expect(format).To(Equal("raw"))
 			})
 			It("returns the requested format if a transcoder exists", func() {
 				mf.Suffix = "flac"
 				mf.BitRate = 1000
-				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "mp3", 0)
+				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "mp3", 0, 0)
 				Expect(format).To(Equal("mp3"))
 				Expect(bitRate).To(Equal(160)) // Default Bit Rate
 			})
 			It("returns raw if requested format is the same as the original and it is not necessary to downsample", func() {
 				mf.Suffix = "mp3"
 				mf.BitRate = 112
-				format, _ := selectTranscodingOptions(ctx, ds, mf, "mp3", 128)
+				format, _ := selectTranscodingOptions(ctx, ds, mf, "mp3", 128, 0)
 				Expect(format).To(Equal("raw"))
 			})
 			It("returns the requested format if requested BitRate is lower than original", func() {
 				mf.Suffix = "mp3"
 				mf.BitRate = 320
-				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "mp3", 192)
+				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "mp3", 192, 0)
 				Expect(format).To(Equal("mp3"))
 				Expect(bitRate).To(Equal(192))
 			})
 			It("returns raw if requested format is the same as the original, but requested BitRate is 0", func() {
 				mf.Suffix = "mp3"
 				mf.BitRate = 320
-				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "mp3", 0)
+				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "mp3", 0, 0)
 				Expect(format).To(Equal("raw"))
 				Expect(bitRate).To(Equal(320))
 			})
+			It("returns the format when same format is requested but with a lower sample rate", func() {
+				mf.Suffix = "flac"
+				mf.BitRate = 2118
+				mf.SampleRate = 96000
+				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "flac", 0, 48000)
+				Expect(format).To(Equal("flac"))
+				Expect(bitRate).To(Equal(0))
+			})
+			It("returns raw when same format is requested with same sample rate", func() {
+				mf.Suffix = "flac"
+				mf.BitRate = 1000
+				mf.SampleRate = 48000
+				format, _ := selectTranscodingOptions(ctx, ds, mf, "flac", 0, 48000)
+				Expect(format).To(Equal("raw"))
+			})
+			It("returns raw when same format is requested with no sample rate constraint", func() {
+				mf.Suffix = "flac"
+				mf.BitRate = 1000
+				mf.SampleRate = 96000
+				format, _ := selectTranscodingOptions(ctx, ds, mf, "flac", 0, 0)
+				Expect(format).To(Equal("raw"))
+			})
 			Context("Downsampling", func() {
 				BeforeEach(func() {
 					conf.Server.DefaultDownsamplingFormat = "opus"
@@ -69,13 +91,13 @@ var _ = Describe("MediaStreamer", func() {
 					mf.BitRate = 960
 				})
 				It("returns the DefaultDownsamplingFormat if a maxBitrate is requested but not the format", func() {
-					format, bitRate := selectTranscodingOptions(ctx, ds, mf, "", 128)
+					format, bitRate := selectTranscodingOptions(ctx, ds, mf, "", 128, 0)
 					Expect(format).To(Equal("opus"))
 					Expect(bitRate).To(Equal(128))
 				})
 				It("returns raw if maxBitrate is equal or greater than original", func() {
 					// This happens with DSub (and maybe other clients?). See https://github.com/navidrome/navidrome/issues/2066
-					format, bitRate := selectTranscodingOptions(ctx, ds, mf, "", 960)
+					format, bitRate := selectTranscodingOptions(ctx, ds, mf, "", 960, 0)
 					Expect(format).To(Equal("raw"))
 					Expect(bitRate).To(Equal(0))
 				})
@@ -90,34 +112,34 @@ var _ = Describe("MediaStreamer", func() {
 			It("returns raw if raw is requested", func() {
 				mf.Suffix = "flac"
 				mf.BitRate = 1000
-				format, _ := selectTranscodingOptions(ctx, ds, mf, "raw", 0)
+				format, _ := selectTranscodingOptions(ctx, ds, mf, "raw", 0, 0)
 				Expect(format).To(Equal("raw"))
 			})
 			It("returns configured format/bitrate as default", func() {
 				mf.Suffix = "flac"
 				mf.BitRate = 1000
-				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "", 0)
+				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "", 0, 0)
 				Expect(format).To(Equal("oga"))
 				Expect(bitRate).To(Equal(96))
 			})
 			It("returns requested format", func() {
 				mf.Suffix = "flac"
 				mf.BitRate = 1000
-				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "mp3", 0)
+				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "mp3", 0, 0)
 				Expect(format).To(Equal("mp3"))
 				Expect(bitRate).To(Equal(160)) // Default Bit Rate
 			})
 			It("returns requested bitrate", func() {
 				mf.Suffix = "flac"
 				mf.BitRate = 1000
-				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "", 80)
+				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "", 80, 0)
 				Expect(format).To(Equal("oga"))
 				Expect(bitRate).To(Equal(80))
 			})
 			It("returns raw if selected bitrate and format is the same as original", func() {
 				mf.Suffix = "mp3"
 				mf.BitRate = 192
-				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "mp3", 192)
+				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "mp3", 192, 0)
 				Expect(format).To(Equal("raw"))
 				Expect(bitRate).To(Equal(0))
 			})
@@ -133,27 +155,27 @@ var _ = Describe("MediaStreamer", func() {
 			It("returns raw if raw is requested", func() {
 				mf.Suffix = "flac"
 				mf.BitRate = 1000
-				format, _ := selectTranscodingOptions(ctx, ds, mf, "raw", 0)
+				format, _ := selectTranscodingOptions(ctx, ds, mf, "raw", 0, 0)
 				Expect(format).To(Equal("raw"))
 			})
 			It("returns configured format/bitrate as default", func() {
 				mf.Suffix = "flac"
 				mf.BitRate = 1000
-				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "", 0)
+				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "", 0, 0)
 				Expect(format).To(Equal("oga"))
 				Expect(bitRate).To(Equal(192))
 			})
 			It("returns requested format", func() {
 				mf.Suffix = "flac"
 				mf.BitRate = 1000
-				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "mp3", 0)
+				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "mp3", 0, 0)
 				Expect(format).To(Equal("mp3"))
 				Expect(bitRate).To(Equal(160)) // Default Bit Rate
 			})
 			It("returns requested bitrate", func() {
 				mf.Suffix = "flac"
 				mf.BitRate = 1000
-				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "", 160)
+				format, bitRate := selectTranscodingOptions(ctx, ds, mf, "", 160, 0)
 				Expect(format).To(Equal("oga"))
 				Expect(bitRate).To(Equal(160))
 			})

core/media_streamer_test.go

@@ -39,34 +39,34 @@ var _ = Describe("MediaStreamer", func() {
 
 	Context("NewStream", func() {
 		It("returns a seekable stream if format is 'raw'", func() {
-			s, err := streamer.NewStream(ctx, "123", "raw", 0, 0)
+			s, err := streamer.NewStream(ctx, core.StreamRequest{ID: "123", Format: "raw"})
 			Expect(err).ToNot(HaveOccurred())
 			Expect(s.Seekable()).To(BeTrue())
 		})
 		It("returns a seekable stream if maxBitRate is 0", func() {
-			s, err := streamer.NewStream(ctx, "123", "mp3", 0, 0)
+			s, err := streamer.NewStream(ctx, core.StreamRequest{ID: "123", Format: "mp3"})
 			Expect(err).ToNot(HaveOccurred())
 			Expect(s.Seekable()).To(BeTrue())
 		})
 		It("returns a seekable stream if maxBitRate is higher than file bitRate", func() {
-			s, err := streamer.NewStream(ctx, "123", "mp3", 320, 0)
+			s, err := streamer.NewStream(ctx, core.StreamRequest{ID: "123", Format: "mp3", BitRate: 320})
 			Expect(err).ToNot(HaveOccurred())
 			Expect(s.Seekable()).To(BeTrue())
 		})
 		It("returns a NON seekable stream if transcode is required", func() {
-			s, err := streamer.NewStream(ctx, "123", "mp3", 64, 0)
+			s, err := streamer.NewStream(ctx, core.StreamRequest{ID: "123", Format: "mp3", BitRate: 64})
 			Expect(err).To(BeNil())
 			Expect(s.Seekable()).To(BeFalse())
 			Expect(s.Duration()).To(Equal(float32(257.0)))
 		})
 		It("returns a seekable stream if the file is complete in the cache", func() {
-			s, err := streamer.NewStream(ctx, "123", "mp3", 32, 0)
+			s, err := streamer.NewStream(ctx, core.StreamRequest{ID: "123", Format: "mp3", BitRate: 32})
 			Expect(err).To(BeNil())
 			_, _ = io.ReadAll(s)
 			_ = s.Close()
 			Eventually(func() bool { return ffmpeg.IsClosed() }, "3s").Should(BeTrue())
 
-			s, err = streamer.NewStream(ctx, "123", "mp3", 32, 0)
+			s, err = streamer.NewStream(ctx, core.StreamRequest{ID: "123", Format: "mp3", BitRate: 32})
 			Expect(err).To(BeNil())
 			Expect(s.Seekable()).To(BeTrue())
 		})

core/playback/queue.go

@@ -3,6 +3,7 @@ package playback
 import (
 	"fmt"
 	"math/rand"
+	"strings"
 
 	"github.com/navidrome/navidrome/log"
 	"github.com/navidrome/navidrome/model"
@@ -21,11 +22,11 @@ func NewQueue() *Queue {
 }
 
 func (pd *Queue) String() string {
-	filenames := ""
+	var filenames strings.Builder
 	for idx, item := range pd.Items {
-		filenames += fmt.Sprint(idx) + ":" + item.Path + " "
+		filenames.WriteString(fmt.Sprint(idx) + ":" + item.Path + " ")
 	}
-	return fmt.Sprintf("#Items: %d, idx: %d, files: %s", len(pd.Items), pd.Index, filenames)
+	return fmt.Sprintf("#Items: %d, idx: %d, files: %s", len(pd.Items), pd.Index, filenames.String())
 }
 
 // returns the current mediafile or nil

core/playlists.go

@@ -45,7 +45,7 @@ func InPlaylistsPath(folder model.Folder) bool {
 		return true
 	}
 	rel, _ := filepath.Rel(folder.LibraryPath, folder.AbsolutePath())
-	for _, path := range strings.Split(conf.Server.PlaylistsPath, string(filepath.ListSeparator)) {
+	for path := range strings.SplitSeq(conf.Server.PlaylistsPath, string(filepath.ListSeparator)) {
 		if match, _ := doublestar.Match(path, rel); match {
 			return true
 		}
@@ -193,8 +193,8 @@ func (s *playlists) parseM3U(ctx context.Context, pls *model.Playlist, folder *m
 			if line == "" || strings.HasPrefix(line, "#") {
 				continue
 			}
-			if strings.HasPrefix(line, "file://") {
-				line = strings.TrimPrefix(line, "file://")
+			if after, ok := strings.CutPrefix(line, "file://"); ok {
+				line = after
 				line, _ = url.QueryUnescape(line)
 			}
 			if !model.IsAudioFile(line) {
@@ -533,7 +533,7 @@ type nspFile struct {
 }
 
 func (i *nspFile) UnmarshalJSON(data []byte) error {
-	m := map[string]interface{}{}
+	m := map[string]any{}
 	err := json.Unmarshal(data, &m)
 	if err != nil {
 		return err

core/scrobbler/play_tracker.go

@@ -212,10 +212,7 @@ func (p *playTracker) NowPlaying(ctx context.Context, playerId string, playerNam
 
 	// Calculate TTL based on remaining track duration. If position exceeds track duration,
 	// remaining is set to 0 to avoid negative TTL.
-	remaining := int(mf.Duration) - position
-	if remaining < 0 {
-		remaining = 0
-	}
+	remaining := max(int(mf.Duration)-position, 0)
 	// Add 5 seconds buffer to ensure the NowPlaying info is available slightly longer than the track duration.
 	ttl := time.Duration(remaining+5) * time.Second
 	_ = p.playMap.AddWithTTL(playerId, info, ttl)

core/share.go

@@ -87,7 +87,7 @@ func (r *shareRepositoryWrapper) newId() (string, error) {
 	}
 }
 
-func (r *shareRepositoryWrapper) Save(entity interface{}) (string, error) {
+func (r *shareRepositoryWrapper) Save(entity any) (string, error) {
 	s := entity.(*model.Share)
 	id, err := r.newId()
 	if err != nil {
@@ -127,7 +127,7 @@ func (r *shareRepositoryWrapper) Save(entity interface{}) (string, error) {
 	return id, err
 }
 
-func (r *shareRepositoryWrapper) Update(id string, entity interface{}, _ ...string) error {
+func (r *shareRepositoryWrapper) Update(id string, entity any, _ ...string) error {
 	cols := []string{"description", "downloadable"}
 
 	// TODO Better handling of Share expiration

core/storage/storagetest/fake_storage.go

@@ -6,6 +6,7 @@ import (
 	"errors"
 	"fmt"
 	"io/fs"
+	"maps"
 	"net/url"
 	"path"
 	"testing/fstest"
@@ -135,9 +136,7 @@ func (ffs *FakeFS) UpdateTags(filePath string, newTags map[string]any, when ...t
 	if err != nil {
 		panic(err)
 	}
-	for k, v := range newTags {
-		tags[k] = v
-	}
+	maps.Copy(tags, newTags)
 	data, _ := json.Marshal(tags)
 	f.Data = data
 	ffs.Touch(filePath, when...)
@@ -180,9 +179,7 @@ func Track(num int, title string, tags ...map[string]any) map[string]any {
 	ts["title"] = title
 	ts["track"] = num
 	for _, t := range tags {
-		for k, v := range t {
-			ts[k] = v
-		}
+		maps.Copy(ts, t)
 	}
 	return ts
 }
@@ -200,9 +197,7 @@ func MP3(tags ...map[string]any) *fstest.MapFile {
 func File(tags ...map[string]any) *fstest.MapFile {
 	ts := map[string]any{}
 	for _, t := range tags {
-		for k, v := range t {
-			ts[k] = v
-		}
+		maps.Copy(ts, t)
 	}
 	modTime := time.Now()
 	if mt, ok := ts[fakeFileInfoModTime]; !ok {

core/transcode/aliases.go

@@ -0,0 +1,87 @@
+package transcode
+
+import (
+	"slices"
+	"strings"
+)
+
+// containerAliasGroups maps each container alias to a canonical group name.
+var containerAliasGroups = func() map[string]string {
+	groups := [][]string{
+		{"aac", "adts", "m4a", "mp4", "m4b", "m4p"},
+		{"mpeg", "mp3", "mp2"},
+		{"ogg", "oga"},
+		{"aif", "aiff"},
+		{"asf", "wma"},
+		{"mpc", "mpp"},
+		{"wv"},
+	}
+	m := make(map[string]string)
+	for _, g := range groups {
+		canonical := g[0]
+		for _, name := range g {
+			m[name] = canonical
+		}
+	}
+	return m
+}()
+
+// codecAliasGroups maps each codec alias to a canonical group name.
+// Codecs within the same group are considered equivalent.
+var codecAliasGroups = func() map[string]string {
+	groups := [][]string{
+		{"aac", "adts"},
+		{"ac3", "ac-3"},
+		{"eac3", "e-ac3", "e-ac-3", "eac-3"},
+		{"mpc7", "musepack7"},
+		{"mpc8", "musepack8"},
+		{"wma1", "wmav1"},
+		{"wma2", "wmav2"},
+		{"wmalossless", "wma9lossless"},
+		{"wmapro", "wma9pro"},
+		{"shn", "shorten"},
+		{"mp4als", "als"},
+	}
+	m := make(map[string]string)
+	for _, g := range groups {
+		for _, name := range g {
+			m[name] = g[0] // canonical = first entry
+		}
+	}
+	return m
+}()
+
+// matchesWithAliases checks if a value matches any entry in candidates,
+// consulting the alias map for equivalent names.
+func matchesWithAliases(value string, candidates []string, aliases map[string]string) bool {
+	value = strings.ToLower(value)
+	canonical := aliases[value]
+	for _, c := range candidates {
+		c = strings.ToLower(c)
+		if c == value {
+			return true
+		}
+		if canonical != "" && aliases[c] == canonical {
+			return true
+		}
+	}
+	return false
+}
+
+// matchesContainer checks if a file suffix matches any of the container names,
+// including common aliases.
+func matchesContainer(suffix string, containers []string) bool {
+	return matchesWithAliases(suffix, containers, containerAliasGroups)
+}
+
+// matchesCodec checks if a codec matches any of the codec names,
+// including common aliases.
+func matchesCodec(codec string, codecs []string) bool {
+	return matchesWithAliases(codec, codecs, codecAliasGroups)
+}
+
+func containsIgnoreCase(slice []string, s string) bool {
+	return slices.ContainsFunc(slice, func(item string) bool {
+		return strings.EqualFold(item, s)
+	})
+}

core/transcode/codec.go

@@ -0,0 +1,59 @@
+package transcode
+
+import "strings"
+
+// isLosslessFormat returns true if the format is a lossless audio codec/format.
+// Note: core/ffmpeg has a separate isLosslessOutputFormat that covers only formats
+// ffmpeg can produce as output (a smaller set). This function covers all known lossless formats
+// for transcoding decision purposes.
+func isLosslessFormat(format string) bool {
+	switch strings.ToLower(format) {
+	case "flac", "alac", "wav", "aiff", "ape", "wv", "tta", "tak", "shn", "dsd":
+		return true
+	}
+	return false
+}
+
+// normalizeSourceSampleRate adjusts the source sample rate for codecs that store
+// it differently than PCM. Currently handles DSD (÷8):
+// DSD64=2822400→352800, DSD128=5644800→705600, etc.
+// For other codecs, returns the rate unchanged.
+func normalizeSourceSampleRate(sampleRate int, codec string) int {
+	if strings.EqualFold(codec, "dsd") && sampleRate > 0 {
+		return sampleRate / 8
+	}
+	return sampleRate
+}
+
+// normalizeSourceBitDepth adjusts the source bit depth for codecs that use
+// non-standard bit depths. Currently handles DSD (1-bit → 24-bit PCM, which is
+// what ffmpeg produces). For other codecs, returns the depth unchanged.
+func normalizeSourceBitDepth(bitDepth int, codec string) int {
+	if strings.EqualFold(codec, "dsd") && bitDepth == 1 {
+		return 24
+	}
+	return bitDepth
+}
+
+// codecFixedOutputSampleRate returns the mandatory output sample rate for codecs
+// that always resample regardless of input (e.g., Opus always outputs 48000Hz).
+// Returns 0 if the codec has no fixed output rate.
+func codecFixedOutputSampleRate(codec string) int {
+	switch strings.ToLower(codec) {
+	case "opus":
+		return 48000
+	}
+	return 0
+}
+
+// codecMaxSampleRate returns the hard maximum output sample rate for a codec.
+// Returns 0 if the codec has no hard limit.
+func codecMaxSampleRate(codec string) int {
+	switch strings.ToLower(codec) {
+	case "mp3":
+		return 48000
+	case "aac":
+		return 96000
+	}
+	return 0
+}

core/transcode/limitations.go

@@ -0,0 +1,206 @@
+package transcode
+
+import (
+	"strconv"
+	"strings"
+
+	"github.com/navidrome/navidrome/model"
+)
+
+// adjustResult represents the outcome of applying a limitation to a transcoded stream value
+type adjustResult int
+
+const (
+	adjustNone      adjustResult = iota // Value already satisfies the limitation
+	adjustAdjusted                      // Value was changed to fit the limitation
+	adjustCannotFit                     // Cannot satisfy the limitation (reject this profile)
+)
+
+// checkLimitations checks codec profile limitations against source media.
+// Returns "" if all limitations pass, or a typed reason string for the first failure.
+func checkLimitations(mf *model.MediaFile, sourceBitrate int, limitations []Limitation) string {
+	for _, lim := range limitations {
+		var ok bool
+		var reason string
+
+		switch lim.Name {
+		case LimitationAudioChannels:
+			ok = checkIntLimitation(mf.Channels, lim.Comparison, lim.Values)
+			reason = "audio channels not supported"
+		case LimitationAudioSamplerate:
+			ok = checkIntLimitation(mf.SampleRate, lim.Comparison, lim.Values)
+			reason = "audio samplerate not supported"
+		case LimitationAudioBitrate:
+			ok = checkIntLimitation(sourceBitrate, lim.Comparison, lim.Values)
+			reason = "audio bitrate not supported"
+		case LimitationAudioBitdepth:
+			ok = checkIntLimitation(mf.BitDepth, lim.Comparison, lim.Values)
+			reason = "audio bitdepth not supported"
+		case LimitationAudioProfile:
+			// TODO: populate source profile when MediaFile has audio profile info
+			ok = checkStringLimitation("", lim.Comparison, lim.Values)
+			reason = "audio profile not supported"
+		default:
+			continue
+		}
+
+		if !ok && lim.Required {
+			return reason
+		}
+	}
+	return ""
+}
+
+// applyLimitation adjusts a transcoded stream parameter to satisfy the limitation.
+// Returns the adjustment result.
+func applyLimitation(sourceBitrate int, lim *Limitation, ts *StreamDetails) adjustResult {
+	switch lim.Name {
+	case LimitationAudioChannels:
+		return applyIntLimitation(lim.Comparison, lim.Values, ts.Channels, func(v int) { ts.Channels = v })
+	case LimitationAudioBitrate:
+		current := ts.Bitrate
+		if current == 0 {
+			current = sourceBitrate
+		}
+		return applyIntLimitation(lim.Comparison, lim.Values, current, func(v int) { ts.Bitrate = v })
+	case LimitationAudioSamplerate:
+		return applyIntLimitation(lim.Comparison, lim.Values, ts.SampleRate, func(v int) { ts.SampleRate = v })
+	case LimitationAudioBitdepth:
+		if ts.BitDepth > 0 {
+			return applyIntLimitation(lim.Comparison, lim.Values, ts.BitDepth, func(v int) { ts.BitDepth = v })
+		}
+	case LimitationAudioProfile:
+		// TODO: implement when audio profile data is available
+	}
+	return adjustNone
+}
+
+// applyIntLimitation applies a limitation comparison to a value.
+// If the value needs adjusting, calls the setter and returns the result.
+func applyIntLimitation(comparison string, values []string, current int, setter func(int)) adjustResult {
+	if len(values) == 0 {
+		return adjustNone
+	}
+
+	switch comparison {
+	case ComparisonLessThanEqual:
+		limit, ok := parseInt(values[0])
+		if !ok {
+			return adjustNone
+		}
+		if current <= limit {
+			return adjustNone
+		}
+		setter(limit)
+		return adjustAdjusted
+	case ComparisonGreaterThanEqual:
+		limit, ok := parseInt(values[0])
+		if !ok {
+			return adjustNone
+		}
+		if current >= limit {
+			return adjustNone
+		}
+		// Cannot upscale
+		return adjustCannotFit
+	case ComparisonEquals:
+		// Check if current value matches any allowed value
+		for _, v := range values {
+			if limit, ok := parseInt(v); ok && current == limit {
+				return adjustNone
+			}
+		}
+		// Find the closest allowed value below current (don't upscale)
+		var closest int
+		found := false
+		for _, v := range values {
+			if limit, ok := parseInt(v); ok && limit < current {
+				if !found || limit > closest {
+					closest = limit
+					found = true
+				}
+			}
+		}
+		if found {
+			setter(closest)
+			return adjustAdjusted
+		}
+		return adjustCannotFit
+	case ComparisonNotEquals:
+		for _, v := range values {
+			if limit, ok := parseInt(v); ok && current == limit {
+				return adjustCannotFit
+			}
+		}
+		return adjustNone
+	}
+
+	return adjustNone
+}
+
+func checkIntLimitation(value int, comparison string, values []string) bool {
+	if len(values) == 0 {
+		return true
+	}
+
+	switch comparison {
+	case ComparisonLessThanEqual:
+		limit, ok := parseInt(values[0])
+		if !ok {
+			return true
+		}
+		return value <= limit
+	case ComparisonGreaterThanEqual:
+		limit, ok := parseInt(values[0])
+		if !ok {
+			return true
+		}
+		return value >= limit
+	case ComparisonEquals:
+		for _, v := range values {
+			if limit, ok := parseInt(v); ok && value == limit {
+				return true
+			}
+		}
+		return false
+	case ComparisonNotEquals:
+		for _, v := range values {
+			if limit, ok := parseInt(v); ok && value == limit {
+				return false
+			}
+		}
+		return true
+	}
+	return true
+}
+
+// checkStringLimitation checks a string value against a limitation.
+// Only Equals and NotEquals comparisons are meaningful for strings.
+// LessThanEqual/GreaterThanEqual are not applicable and always pass.
+func checkStringLimitation(value string, comparison string, values []string) bool {
+	switch comparison {
+	case ComparisonEquals:
+		for _, v := range values {
+			if strings.EqualFold(value, v) {
+				return true
+			}
+		}
+		return false
+	case ComparisonNotEquals:
+		for _, v := range values {
+			if strings.EqualFold(value, v) {
+				return false
+			}
+		}
+		return true
+	}
+	return true
+}
+
+func parseInt(s string) (int, bool) {
+	v, err := strconv.Atoi(s)
+	if err != nil || v < 0 {
+		return 0, false
+	}
+	return v, true
+}

core/transcode/transcode.go

@@ -0,0 +1,359 @@
+package transcode
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/navidrome/navidrome/core/auth"
+	"github.com/navidrome/navidrome/log"
+	"github.com/navidrome/navidrome/model"
+)
+
+const (
+	tokenTTL       = 12 * time.Hour
+	defaultBitrate = 256 // kbps
+)
+
+func NewDecider(ds model.DataStore) Decider {
+	return &deciderService{
+		ds: ds,
+	}
+}
+
+type deciderService struct {
+	ds model.DataStore
+}
+
+func (s *deciderService) MakeDecision(ctx context.Context, mf *model.MediaFile, clientInfo *ClientInfo) (*Decision, error) {
+	decision := &Decision{
+		MediaID: mf.ID,
+	}
+
+	sourceBitrate := mf.BitRate // kbps
+
+	log.Trace(ctx, "Making transcode decision", "mediaID", mf.ID, "container", mf.Suffix,
+		"codec", mf.AudioCodec(), "bitrate", sourceBitrate, "channels", mf.Channels,
+		"sampleRate", mf.SampleRate, "lossless", mf.IsLossless(), "client", clientInfo.Name)
+
+	// Build source stream details
+	decision.SourceStream = buildSourceStream(mf)
+
+	// Check global bitrate constraint first.
+	if clientInfo.MaxAudioBitrate > 0 && sourceBitrate > clientInfo.MaxAudioBitrate {
+		log.Trace(ctx, "Global bitrate constraint exceeded, skipping direct play",
+			"sourceBitrate", sourceBitrate, "maxAudioBitrate", clientInfo.MaxAudioBitrate)
+		decision.TranscodeReasons = append(decision.TranscodeReasons, "audio bitrate not supported")
+		// Skip direct play profiles entirely — global constraint fails
+	} else {
+		// Try direct play profiles, collecting reasons for each failure
+		for _, profile := range clientInfo.DirectPlayProfiles {
+			if reason := s.checkDirectPlayProfile(mf, sourceBitrate, &profile, clientInfo); reason == "" {
+				decision.CanDirectPlay = true
+				decision.TranscodeReasons = nil // Clear any previously collected reasons
+				break
+			} else {
+				decision.TranscodeReasons = append(decision.TranscodeReasons, reason)
+			}
+		}
+	}
+
+	// If direct play is possible, we're done
+	if decision.CanDirectPlay {
+		log.Debug(ctx, "Transcode decision: direct play", "mediaID", mf.ID, "container", mf.Suffix, "codec", mf.AudioCodec())
+		return decision, nil
+	}
+
+	// Try transcoding profiles (in order of preference)
+	for _, profile := range clientInfo.TranscodingProfiles {
+		if ts, transcodeFormat := s.computeTranscodedStream(ctx, mf, sourceBitrate, &profile, clientInfo); ts != nil {
+			decision.CanTranscode = true
+			decision.TargetFormat = transcodeFormat
+			decision.TargetBitrate = ts.Bitrate
+			decision.TargetChannels = ts.Channels
+			decision.TargetSampleRate = ts.SampleRate
+			decision.TargetBitDepth = ts.BitDepth
+			decision.TranscodeStream = ts
+			break
+		}
+	}
+
+	if decision.CanTranscode {
+		log.Debug(ctx, "Transcode decision: transcode", "mediaID", mf.ID,
+			"targetFormat", decision.TargetFormat, "targetBitrate", decision.TargetBitrate,
+			"targetChannels", decision.TargetChannels, "reasons", decision.TranscodeReasons)
+	}
+
+	// If neither direct play nor transcode is possible
+	if !decision.CanDirectPlay && !decision.CanTranscode {
+		decision.ErrorReason = "no compatible playback profile found"
+		log.Warn(ctx, "Transcode decision: no compatible profile", "mediaID", mf.ID,
+			"container", mf.Suffix, "codec", mf.AudioCodec(), "reasons", decision.TranscodeReasons)
+	}
+
+	return decision, nil
+}
+
+func buildSourceStream(mf *model.MediaFile) StreamDetails {
+	return StreamDetails{
+		Container:  mf.Suffix,
+		Codec:      mf.AudioCodec(),
+		Bitrate:    mf.BitRate,
+		SampleRate: mf.SampleRate,
+		BitDepth:   mf.BitDepth,
+		Channels:   mf.Channels,
+		Duration:   mf.Duration,
+		Size:       mf.Size,
+		IsLossless: mf.IsLossless(),
+	}
+}
+
+// checkDirectPlayProfile returns "" if the profile matches (direct play OK),
+// or a typed reason string if it doesn't match.
+func (s *deciderService) checkDirectPlayProfile(mf *model.MediaFile, sourceBitrate int, profile *DirectPlayProfile, clientInfo *ClientInfo) string {
+	// Check protocol (only http for now)
+	if len(profile.Protocols) > 0 && !containsIgnoreCase(profile.Protocols, ProtocolHTTP) {
+		return "protocol not supported"
+	}
+
+	// Check container
+	if len(profile.Containers) > 0 && !matchesContainer(mf.Suffix, profile.Containers) {
+		return "container not supported"
+	}
+
+	// Check codec
+	if len(profile.AudioCodecs) > 0 && !matchesCodec(mf.AudioCodec(), profile.AudioCodecs) {
+		return "audio codec not supported"
+	}
+
+	// Check channels
+	if profile.MaxAudioChannels > 0 && mf.Channels > profile.MaxAudioChannels {
+		return "audio channels not supported"
+	}
+
+	// Check codec-specific limitations
+	for _, codecProfile := range clientInfo.CodecProfiles {
+		if strings.EqualFold(codecProfile.Type, CodecProfileTypeAudio) && matchesCodec(mf.AudioCodec(), []string{codecProfile.Name}) {
+			if reason := checkLimitations(mf, sourceBitrate, codecProfile.Limitations); reason != "" {
+				return reason
+			}
+		}
+	}
+
+	return ""
+}
+
+// computeTranscodedStream attempts to build a valid transcoded stream for the given profile.
+// Returns the stream details and the internal transcoding format (which may differ from the
+// response container when a codec fallback occurs, e.g., "mp4"→"aac").
+// Returns nil, "" if the profile cannot produce a valid output.
+func (s *deciderService) computeTranscodedStream(ctx context.Context, mf *model.MediaFile, sourceBitrate int, profile *Profile, clientInfo *ClientInfo) (*StreamDetails, string) {
+	// Check protocol (only http for now)
+	if profile.Protocol != "" && !strings.EqualFold(profile.Protocol, ProtocolHTTP) {
+		log.Trace(ctx, "Skipping transcoding profile: unsupported protocol", "protocol", profile.Protocol)
+		return nil, ""
+	}
+
+	responseContainer, targetFormat := s.resolveTargetFormat(ctx, profile)
+	if targetFormat == "" {
+		return nil, ""
+	}
+
+	targetIsLossless := isLosslessFormat(targetFormat)
+
+	// Reject lossy to lossless conversion
+	if !mf.IsLossless() && targetIsLossless {
+		log.Trace(ctx, "Skipping transcoding profile: lossy to lossless not allowed", "targetFormat", targetFormat)
+		return nil, ""
+	}
+
+	ts := &StreamDetails{
+		Container:  responseContainer,
+		Codec:      strings.ToLower(profile.AudioCodec),
+		SampleRate: normalizeSourceSampleRate(mf.SampleRate, mf.AudioCodec()),
+		Channels:   mf.Channels,
+		BitDepth:   normalizeSourceBitDepth(mf.BitDepth, mf.AudioCodec()),
+		IsLossless: targetIsLossless,
+	}
+	if ts.Codec == "" {
+		ts.Codec = targetFormat
+	}
+
+	// Apply codec-intrinsic sample rate adjustments before codec profile limitations
+	if fixedRate := codecFixedOutputSampleRate(ts.Codec); fixedRate > 0 {
+		ts.SampleRate = fixedRate
+	}
+	if maxRate := codecMaxSampleRate(ts.Codec); maxRate > 0 && ts.SampleRate > maxRate {
+		ts.SampleRate = maxRate
+	}
+
+	// Determine target bitrate (all in kbps)
+	if ok := s.computeBitrate(ctx, mf, sourceBitrate, targetFormat, targetIsLossless, clientInfo, ts); !ok {
+		return nil, ""
+	}
+
+	// Apply MaxAudioChannels from the transcoding profile
+	if profile.MaxAudioChannels > 0 && mf.Channels > profile.MaxAudioChannels {
+		ts.Channels = profile.MaxAudioChannels
+	}
+
+	// Apply codec profile limitations to the TARGET codec
+	if ok := s.applyCodecLimitations(ctx, sourceBitrate, targetFormat, targetIsLossless, clientInfo, ts); !ok {
+		return nil, ""
+	}
+
+	return ts, targetFormat
+}
+
+// resolveTargetFormat determines the response container and internal target format
+// by looking up transcoding configs. Returns ("", "") if no config found.
+func (s *deciderService) resolveTargetFormat(ctx context.Context, profile *Profile) (responseContainer, targetFormat string) {
+	responseContainer = strings.ToLower(profile.Container)
+	targetFormat = responseContainer
+	if targetFormat == "" {
+		targetFormat = strings.ToLower(profile.AudioCodec)
+		responseContainer = targetFormat
+	}
+
+	// Try the container first, then fall back to the audioCodec (e.g. "ogg" → "opus", "mp4" → "aac").
+	_, err := s.ds.Transcoding(ctx).FindByFormat(targetFormat)
+	if errors.Is(err, model.ErrNotFound) && profile.AudioCodec != "" && !strings.EqualFold(targetFormat, profile.AudioCodec) {
+		codec := strings.ToLower(profile.AudioCodec)
+		log.Trace(ctx, "No transcoding config for container, trying audioCodec", "container", targetFormat, "audioCodec", codec)
+		_, err = s.ds.Transcoding(ctx).FindByFormat(codec)
+		if err == nil {
+			targetFormat = codec
+		}
+	}
+	if err != nil {
+		if !errors.Is(err, model.ErrNotFound) {
+			log.Error(ctx, "Error looking up transcoding config", "format", targetFormat, err)
+		} else {
+			log.Trace(ctx, "Skipping transcoding profile: no transcoding config", "targetFormat", targetFormat)
+		}
+		return "", ""
+	}
+	return responseContainer, targetFormat
+}
+
+// computeBitrate determines the target bitrate for the transcoded stream.
+// Returns false if the profile should be rejected.
+func (s *deciderService) computeBitrate(ctx context.Context, mf *model.MediaFile, sourceBitrate int, targetFormat string, targetIsLossless bool, clientInfo *ClientInfo, ts *StreamDetails) bool {
+	if mf.IsLossless() {
+		if !targetIsLossless {
+			if clientInfo.MaxTranscodingAudioBitrate > 0 {
+				ts.Bitrate = clientInfo.MaxTranscodingAudioBitrate
+			} else {
+				ts.Bitrate = defaultBitrate
+			}
+		} else {
+			if clientInfo.MaxAudioBitrate > 0 && sourceBitrate > clientInfo.MaxAudioBitrate {
+				log.Trace(ctx, "Skipping transcoding profile: lossless target exceeds bitrate limit",
+					"targetFormat", targetFormat, "sourceBitrate", sourceBitrate, "maxAudioBitrate", clientInfo.MaxAudioBitrate)
+				return false
+			}
+		}
+	} else {
+		ts.Bitrate = sourceBitrate
+	}
+
+	// Apply maxAudioBitrate as final cap
+	if clientInfo.MaxAudioBitrate > 0 && ts.Bitrate > 0 && ts.Bitrate > clientInfo.MaxAudioBitrate {
+		ts.Bitrate = clientInfo.MaxAudioBitrate
+	}
+	return true
+}
+
+// applyCodecLimitations applies codec profile limitations to the transcoded stream.
+// Returns false if the profile should be rejected.
+func (s *deciderService) applyCodecLimitations(ctx context.Context, sourceBitrate int, targetFormat string, targetIsLossless bool, clientInfo *ClientInfo, ts *StreamDetails) bool {
+	targetCodec := ts.Codec
+	for _, codecProfile := range clientInfo.CodecProfiles {
+		if !strings.EqualFold(codecProfile.Type, CodecProfileTypeAudio) {
+			continue
+		}
+		if !matchesCodec(targetCodec, []string{codecProfile.Name}) {
+			continue
+		}
+		for _, lim := range codecProfile.Limitations {
+			result := applyLimitation(sourceBitrate, &lim, ts)
+			if strings.EqualFold(lim.Name, LimitationAudioBitrate) && targetIsLossless && result == adjustAdjusted {
+				log.Trace(ctx, "Skipping transcoding profile: cannot adjust bitrate for lossless target",
+					"targetFormat", targetFormat, "codec", targetCodec, "limitation", lim.Name)
+				return false
+			}
+			if result == adjustCannotFit {
+				log.Trace(ctx, "Skipping transcoding profile: codec limitation cannot be satisfied",
+					"targetFormat", targetFormat, "codec", targetCodec, "limitation", lim.Name,
+					"comparison", lim.Comparison, "values", lim.Values)
+				return false
+			}
+		}
+	}
+	return true
+}
+
+func (s *deciderService) CreateTranscodeParams(decision *Decision) (string, error) {
+	exp := time.Now().Add(tokenTTL)
+	claims := map[string]any{
+		"mid": decision.MediaID,
+		"dp":  decision.CanDirectPlay,
+	}
+	if decision.CanTranscode && decision.TargetFormat != "" {
+		claims["fmt"] = decision.TargetFormat
+		claims["br"] = decision.TargetBitrate
+		if decision.TargetChannels > 0 {
+			claims["ch"] = decision.TargetChannels
+		}
+		if decision.TargetSampleRate > 0 {
+			claims["sr"] = decision.TargetSampleRate
+		}
+		if decision.TargetBitDepth > 0 {
+			claims["bd"] = decision.TargetBitDepth
+		}
+	}
+	return auth.CreateExpiringPublicToken(exp, claims)
+}
+
+func (s *deciderService) ParseTranscodeParams(token string) (*Params, error) {
+	claims, err := auth.Validate(token)
+	if err != nil {
+		return nil, err
+	}
+
+	params := &Params{}
+
+	// Required claims
+	mid, ok := claims["mid"].(string)
+	if !ok || mid == "" {
+		return nil, fmt.Errorf("invalid transcode token: missing media ID")
+	}
+	params.MediaID = mid
+
+	dp, ok := claims["dp"].(bool)
+	if !ok {
+		return nil, fmt.Errorf("invalid transcode token: missing direct play flag")
+	}
+	params.DirectPlay = dp
+
+	// Optional claims (legitimately absent for direct-play tokens)
+	if f, ok := claims["fmt"].(string); ok {
+		params.TargetFormat = f
+	}
+	if br, ok := claims["br"].(float64); ok {
+		params.TargetBitrate = int(br)
+	}
+	if ch, ok := claims["ch"].(float64); ok {
+		params.TargetChannels = int(ch)
+	}
+	if sr, ok := claims["sr"].(float64); ok {
+		params.TargetSampleRate = int(sr)
+	}
+	if bd, ok := claims["bd"].(float64); ok {
+		params.TargetBitDepth = int(bd)
+	}
+
+	return params, nil
+}

core/transcode/transcode_suite_test.go

@@ -0,0 +1,17 @@
+package transcode
+
+import (
+	"testing"
+
+	"github.com/navidrome/navidrome/log"
+	"github.com/navidrome/navidrome/tests"
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+func TestTranscode(t *testing.T) {
+	tests.Init(t, false)
+	log.SetLevel(log.LevelFatal)
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Transcode Suite")
+}

core/transcode/transcode_test.go

@@ -0,0 +1,976 @@
+package transcode
+
+import (
+	"context"
+
+	"github.com/navidrome/navidrome/core/auth"
+	"github.com/navidrome/navidrome/model"
+	"github.com/navidrome/navidrome/tests"
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Decider", func() {
+	var (
+		ds  *tests.MockDataStore
+		svc Decider
+		ctx context.Context
+	)
+
+	BeforeEach(func() {
+		ctx = context.Background()
+		ds = &tests.MockDataStore{
+			MockedProperty:    &tests.MockedPropertyRepo{},
+			MockedTranscoding: &tests.MockTranscodingRepo{},
+		}
+		auth.Init(ds)
+		svc = NewDecider(ds)
+	})
+
+	Describe("MakeDecision", func() {
+		Context("Direct Play", func() {
+			It("allows direct play when profile matches", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "mp3", Codec: "MP3", BitRate: 320, Channels: 2, SampleRate: 44100}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"mp3"}, AudioCodecs: []string{"mp3"}, Protocols: []string{"http"}, MaxAudioChannels: 2},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeTrue())
+				Expect(decision.CanTranscode).To(BeFalse())
+				Expect(decision.TranscodeReasons).To(BeEmpty())
+			})
+
+			It("rejects direct play when container doesn't match", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"mp3"}, Protocols: []string{"http"}},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeFalse())
+				Expect(decision.TranscodeReasons).To(ContainElement("container not supported"))
+			})
+
+			It("rejects direct play when codec doesn't match", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "m4a", Codec: "ALAC", BitRate: 1000, Channels: 2}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"m4a"}, AudioCodecs: []string{"aac"}, Protocols: []string{"http"}},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeFalse())
+				Expect(decision.TranscodeReasons).To(ContainElement("audio codec not supported"))
+			})
+
+			It("rejects direct play when channels exceed limit", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 6}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"flac"}, Protocols: []string{"http"}, MaxAudioChannels: 2},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeFalse())
+				Expect(decision.TranscodeReasons).To(ContainElement("audio channels not supported"))
+			})
+
+			It("handles container aliases (aac -> m4a)", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "m4a", Codec: "AAC", BitRate: 256, Channels: 2}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"aac"}, AudioCodecs: []string{"aac"}, Protocols: []string{"http"}},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeTrue())
+			})
+
+			It("handles container aliases (mp4 -> m4a)", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "m4a", Codec: "AAC", BitRate: 256, Channels: 2}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"mp4"}, AudioCodecs: []string{"aac"}, Protocols: []string{"http"}},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeTrue())
+			})
+
+			It("handles codec aliases (adts -> aac)", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "m4a", Codec: "AAC", BitRate: 256, Channels: 2}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"m4a"}, AudioCodecs: []string{"adts"}, Protocols: []string{"http"}},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeTrue())
+			})
+
+			It("allows when protocol list is empty (any protocol)", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"flac"}, AudioCodecs: []string{"flac"}},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeTrue())
+			})
+
+			It("allows when both container and codec lists are empty (wildcard)", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "mp3", Codec: "MP3", BitRate: 128, Channels: 2}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{}, AudioCodecs: []string{}},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeTrue())
+			})
+		})
+
+		Context("MaxAudioBitrate constraint", func() {
+			It("revokes direct play when bitrate exceeds maxAudioBitrate", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1500, Channels: 2}
+				ci := &ClientInfo{
+					MaxAudioBitrate: 500, // kbps
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"flac"}, Protocols: []string{"http"}},
+					},
+					TranscodingProfiles: []Profile{
+						{Container: "mp3", AudioCodec: "mp3", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeFalse())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TranscodeReasons).To(ContainElement("audio bitrate not supported"))
+			})
+		})
+
+		Context("Transcoding", func() {
+			It("selects transcoding when direct play isn't possible", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2, SampleRate: 44100, BitDepth: 16}
+				ci := &ClientInfo{
+					MaxTranscodingAudioBitrate: 256, // kbps
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"mp3"}, Protocols: []string{"http"}},
+					},
+					TranscodingProfiles: []Profile{
+						{Container: "mp3", AudioCodec: "mp3", Protocol: "http", MaxAudioChannels: 2},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeFalse())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TargetFormat).To(Equal("mp3"))
+				Expect(decision.TargetBitrate).To(Equal(256)) // kbps
+				Expect(decision.TranscodeReasons).To(ContainElement("container not supported"))
+			})
+
+			It("rejects lossy to lossless transcoding", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "mp3", Codec: "MP3", BitRate: 320, Channels: 2}
+				ci := &ClientInfo{
+					TranscodingProfiles: []Profile{
+						{Container: "flac", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeFalse())
+			})
+
+			It("uses default bitrate when client doesn't specify", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2, BitDepth: 16}
+				ci := &ClientInfo{
+					TranscodingProfiles: []Profile{
+						{Container: "mp3", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TargetBitrate).To(Equal(defaultBitrate)) // 256 kbps
+			})
+
+			It("preserves lossy bitrate when under max", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "ogg", BitRate: 192, Channels: 2}
+				ci := &ClientInfo{
+					MaxTranscodingAudioBitrate: 256, // kbps
+					TranscodingProfiles: []Profile{
+						{Container: "mp3", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TargetBitrate).To(Equal(192)) // source bitrate in kbps
+			})
+
+			It("rejects unsupported transcoding format", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2}
+				ci := &ClientInfo{
+					TranscodingProfiles: []Profile{
+						{Container: "wav", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeFalse())
+			})
+
+			It("applies maxAudioBitrate as final cap on transcoded stream", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "mp3", Codec: "MP3", BitRate: 320, Channels: 2}
+				ci := &ClientInfo{
+					MaxAudioBitrate: 96, // kbps
+					TranscodingProfiles: []Profile{
+						{Container: "mp3", AudioCodec: "mp3", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TargetBitrate).To(Equal(96)) // capped by maxAudioBitrate
+			})
+
+			It("selects first valid transcoding profile in order", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2, SampleRate: 48000, BitDepth: 16}
+				ci := &ClientInfo{
+					MaxTranscodingAudioBitrate: 320,
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"mp3"}, Protocols: []string{"http"}},
+					},
+					TranscodingProfiles: []Profile{
+						{Container: "opus", AudioCodec: "opus", Protocol: "http"},
+						{Container: "mp3", AudioCodec: "mp3", Protocol: "http", MaxAudioChannels: 2},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TargetFormat).To(Equal("opus"))
+			})
+		})
+
+		Context("Lossless to lossless transcoding", func() {
+			It("allows lossless to lossless when samplerate needs downsampling", func() {
+				// MockTranscodingRepo doesn't support "flac" format, so this would fail to find a config.
+				// This test documents the behavior: lossless→lossless requires server transcoding config.
+				mf := &model.MediaFile{ID: "1", Suffix: "dsf", Codec: "DSD", BitRate: 5644, Channels: 2, SampleRate: 176400, BitDepth: 1}
+				ci := &ClientInfo{
+					MaxAudioBitrate: 1000,
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"flac"}, Protocols: []string{"http"}},
+					},
+					TranscodingProfiles: []Profile{
+						{Container: "mp3", AudioCodec: "mp3", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TargetFormat).To(Equal("mp3"))
+			})
+
+			It("sets IsLossless=true on transcoded stream when target is lossless", func() {
+				// Simulate DSD→FLAC transcoding by using a mock that supports "flac"
+				mockTranscoding := &tests.MockTranscodingRepo{}
+				ds.MockedTranscoding = mockTranscoding
+				svc = NewDecider(ds)
+
+				// MockTranscodingRepo doesn't support flac, so this will skip lossless profile.
+				// Use mp3 which is supported as the fallback.
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2, SampleRate: 96000, BitDepth: 24}
+				ci := &ClientInfo{
+					MaxTranscodingAudioBitrate: 320,
+					TranscodingProfiles: []Profile{
+						{Container: "mp3", AudioCodec: "mp3", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TranscodeStream.IsLossless).To(BeFalse()) // mp3 is lossy
+			})
+		})
+
+		Context("No compatible profile", func() {
+			It("returns error when nothing matches", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 6}
+				ci := &ClientInfo{}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeFalse())
+				Expect(decision.CanTranscode).To(BeFalse())
+				Expect(decision.ErrorReason).To(Equal("no compatible playback profile found"))
+			})
+		})
+
+		Context("Codec limitations on direct play", func() {
+			It("rejects direct play when codec limitation fails (required)", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "mp3", Codec: "MP3", BitRate: 512, Channels: 2, SampleRate: 44100}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"mp3"}, AudioCodecs: []string{"mp3"}, Protocols: []string{"http"}},
+					},
+					CodecProfiles: []CodecProfile{
+						{
+							Type: CodecProfileTypeAudio,
+							Name: "mp3",
+							Limitations: []Limitation{
+								{Name: LimitationAudioBitrate, Comparison: ComparisonLessThanEqual, Values: []string{"320"}, Required: true},
+							},
+						},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeFalse())
+				Expect(decision.TranscodeReasons).To(ContainElement("audio bitrate not supported"))
+			})
+
+			It("allows direct play when optional limitation fails", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "mp3", Codec: "MP3", BitRate: 512, Channels: 2, SampleRate: 44100}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"mp3"}, AudioCodecs: []string{"mp3"}, Protocols: []string{"http"}},
+					},
+					CodecProfiles: []CodecProfile{
+						{
+							Type: CodecProfileTypeAudio,
+							Name: "mp3",
+							Limitations: []Limitation{
+								{Name: LimitationAudioBitrate, Comparison: ComparisonLessThanEqual, Values: []string{"320"}, Required: false},
+							},
+						},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeTrue())
+			})
+
+			It("handles Equals comparison with multiple values", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2, SampleRate: 44100}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"flac"}, Protocols: []string{"http"}},
+					},
+					CodecProfiles: []CodecProfile{
+						{
+							Type: CodecProfileTypeAudio,
+							Name: "flac",
+							Limitations: []Limitation{
+								{Name: LimitationAudioChannels, Comparison: ComparisonEquals, Values: []string{"1", "2"}, Required: true},
+							},
+						},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeTrue())
+			})
+
+			It("rejects when Equals comparison doesn't match any value", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 6, SampleRate: 44100}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"flac"}, Protocols: []string{"http"}},
+					},
+					CodecProfiles: []CodecProfile{
+						{
+							Type: CodecProfileTypeAudio,
+							Name: "flac",
+							Limitations: []Limitation{
+								{Name: LimitationAudioChannels, Comparison: ComparisonEquals, Values: []string{"1", "2"}, Required: true},
+							},
+						},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeFalse())
+			})
+
+			It("rejects direct play when audioProfile limitation fails (required)", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "m4a", Codec: "AAC", BitRate: 256, Channels: 2, SampleRate: 44100}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"m4a"}, AudioCodecs: []string{"aac"}, Protocols: []string{"http"}},
+					},
+					CodecProfiles: []CodecProfile{
+						{
+							Type: CodecProfileTypeAudio,
+							Name: "aac",
+							Limitations: []Limitation{
+								{Name: LimitationAudioProfile, Comparison: ComparisonEquals, Values: []string{"LC"}, Required: true},
+							},
+						},
+					},
+				}
+				// Source profile is empty (not yet populated from scanner), so Equals("LC") fails
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeFalse())
+				Expect(decision.TranscodeReasons).To(ContainElement("audio profile not supported"))
+			})
+
+			It("allows direct play when audioProfile limitation is optional", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "m4a", Codec: "AAC", BitRate: 256, Channels: 2, SampleRate: 44100}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"m4a"}, AudioCodecs: []string{"aac"}, Protocols: []string{"http"}},
+					},
+					CodecProfiles: []CodecProfile{
+						{
+							Type: CodecProfileTypeAudio,
+							Name: "aac",
+							Limitations: []Limitation{
+								{Name: LimitationAudioProfile, Comparison: ComparisonEquals, Values: []string{"LC"}, Required: false},
+							},
+						},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeTrue())
+			})
+
+			It("rejects direct play due to samplerate limitation", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2, SampleRate: 96000, BitDepth: 24}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"flac"}, Protocols: []string{"http"}},
+					},
+					CodecProfiles: []CodecProfile{
+						{
+							Type: CodecProfileTypeAudio,
+							Name: "flac",
+							Limitations: []Limitation{
+								{Name: LimitationAudioSamplerate, Comparison: ComparisonLessThanEqual, Values: []string{"48000"}, Required: true},
+							},
+						},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeFalse())
+				Expect(decision.TranscodeReasons).To(ContainElement("audio samplerate not supported"))
+			})
+		})
+
+		Context("Codec limitations on transcoded output", func() {
+			It("applies bitrate limitation to transcoded stream", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "mp3", Codec: "MP3", BitRate: 192, Channels: 2, SampleRate: 44100}
+				ci := &ClientInfo{
+					MaxAudioBitrate: 96, // force transcode
+					TranscodingProfiles: []Profile{
+						{Container: "mp3", AudioCodec: "mp3", Protocol: "http"},
+					},
+					CodecProfiles: []CodecProfile{
+						{
+							Type: CodecProfileTypeAudio,
+							Name: "mp3",
+							Limitations: []Limitation{
+								{Name: LimitationAudioBitrate, Comparison: ComparisonLessThanEqual, Values: []string{"96"}, Required: true},
+							},
+						},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TranscodeStream.Bitrate).To(Equal(96))
+			})
+
+			It("applies channel limitation to transcoded stream", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 6, SampleRate: 48000, BitDepth: 16}
+				ci := &ClientInfo{
+					MaxTranscodingAudioBitrate: 320,
+					TranscodingProfiles: []Profile{
+						{Container: "mp3", AudioCodec: "mp3", Protocol: "http"},
+					},
+					CodecProfiles: []CodecProfile{
+						{
+							Type: CodecProfileTypeAudio,
+							Name: "mp3",
+							Limitations: []Limitation{
+								{Name: LimitationAudioChannels, Comparison: ComparisonLessThanEqual, Values: []string{"2"}, Required: true},
+							},
+						},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TranscodeStream.Channels).To(Equal(2))
+			})
+
+			It("applies samplerate limitation to transcoded stream", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2, SampleRate: 96000, BitDepth: 24}
+				ci := &ClientInfo{
+					MaxTranscodingAudioBitrate: 320,
+					TranscodingProfiles: []Profile{
+						{Container: "mp3", AudioCodec: "mp3", Protocol: "http"},
+					},
+					CodecProfiles: []CodecProfile{
+						{
+							Type: CodecProfileTypeAudio,
+							Name: "mp3",
+							Limitations: []Limitation{
+								{Name: LimitationAudioSamplerate, Comparison: ComparisonLessThanEqual, Values: []string{"48000"}, Required: true},
+							},
+						},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TranscodeStream.SampleRate).To(Equal(48000))
+			})
+
+			It("applies bitdepth limitation to transcoded stream", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2, SampleRate: 96000, BitDepth: 24}
+				ci := &ClientInfo{
+					TranscodingProfiles: []Profile{
+						{Container: "flac", AudioCodec: "flac", Protocol: "http"},
+					},
+					CodecProfiles: []CodecProfile{
+						{
+							Type: CodecProfileTypeAudio,
+							Name: "flac",
+							Limitations: []Limitation{
+								{Name: LimitationAudioBitdepth, Comparison: ComparisonLessThanEqual, Values: []string{"16"}, Required: true},
+							},
+						},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TranscodeStream.BitDepth).To(Equal(16))
+				Expect(decision.TargetBitDepth).To(Equal(16))
+			})
+
+			It("preserves source bit depth when no limitation applies", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2, SampleRate: 44100, BitDepth: 24}
+				ci := &ClientInfo{
+					TranscodingProfiles: []Profile{
+						{Container: "flac", AudioCodec: "flac", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TranscodeStream.BitDepth).To(Equal(24))
+				Expect(decision.TargetBitDepth).To(Equal(24))
+			})
+
+			It("rejects transcoding profile when GreaterThanEqual cannot be satisfied", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2, SampleRate: 44100, BitDepth: 16}
+				ci := &ClientInfo{
+					MaxTranscodingAudioBitrate: 320,
+					TranscodingProfiles: []Profile{
+						{Container: "mp3", AudioCodec: "mp3", Protocol: "http"},
+					},
+					CodecProfiles: []CodecProfile{
+						{
+							Type: CodecProfileTypeAudio,
+							Name: "mp3",
+							Limitations: []Limitation{
+								{Name: LimitationAudioSamplerate, Comparison: ComparisonGreaterThanEqual, Values: []string{"96000"}, Required: true},
+							},
+						},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeFalse())
+			})
+		})
+
+		Context("DSD sample rate conversion", func() {
+			It("converts DSD sample rate to PCM-equivalent in decision", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "dsf", Codec: "DSD", BitRate: 5644, Channels: 2, SampleRate: 2822400, BitDepth: 1}
+				ci := &ClientInfo{
+					MaxTranscodingAudioBitrate: 320,
+					TranscodingProfiles: []Profile{
+						{Container: "mp3", AudioCodec: "mp3", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TargetFormat).To(Equal("mp3"))
+				// DSD64 2822400 / 8 = 352800, capped by MP3 max of 48000
+				Expect(decision.TranscodeStream.SampleRate).To(Equal(48000))
+				Expect(decision.TargetSampleRate).To(Equal(48000))
+				// DSD 1-bit → 24-bit PCM
+				Expect(decision.TranscodeStream.BitDepth).To(Equal(24))
+				Expect(decision.TargetBitDepth).To(Equal(24))
+			})
+
+			It("converts DSD sample rate for FLAC target without codec limit", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "dsf", Codec: "DSD", BitRate: 5644, Channels: 2, SampleRate: 2822400, BitDepth: 1}
+				ci := &ClientInfo{
+					TranscodingProfiles: []Profile{
+						{Container: "flac", AudioCodec: "flac", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TargetFormat).To(Equal("flac"))
+				// DSD64 2822400 / 8 = 352800, FLAC has no hard max
+				Expect(decision.TranscodeStream.SampleRate).To(Equal(352800))
+				Expect(decision.TargetSampleRate).To(Equal(352800))
+				// DSD 1-bit → 24-bit PCM
+				Expect(decision.TranscodeStream.BitDepth).To(Equal(24))
+				Expect(decision.TargetBitDepth).To(Equal(24))
+			})
+
+			It("applies codec profile limit to DSD-converted FLAC sample rate", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "dsf", Codec: "DSD", BitRate: 5644, Channels: 2, SampleRate: 2822400, BitDepth: 1}
+				ci := &ClientInfo{
+					TranscodingProfiles: []Profile{
+						{Container: "flac", AudioCodec: "flac", Protocol: "http"},
+					},
+					CodecProfiles: []CodecProfile{
+						{
+							Type: CodecProfileTypeAudio,
+							Name: "flac",
+							Limitations: []Limitation{
+								{Name: LimitationAudioSamplerate, Comparison: ComparisonLessThanEqual, Values: []string{"48000"}, Required: true},
+							},
+						},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				// DSD64 2822400 / 8 = 352800, capped by codec profile limit of 48000
+				Expect(decision.TranscodeStream.SampleRate).To(Equal(48000))
+				Expect(decision.TargetSampleRate).To(Equal(48000))
+				// DSD 1-bit → 24-bit PCM
+				Expect(decision.TranscodeStream.BitDepth).To(Equal(24))
+				Expect(decision.TargetBitDepth).To(Equal(24))
+			})
+
+			It("applies audioBitdepth limitation to DSD-converted bit depth", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "dsf", Codec: "DSD", BitRate: 5644, Channels: 2, SampleRate: 2822400, BitDepth: 1}
+				ci := &ClientInfo{
+					TranscodingProfiles: []Profile{
+						{Container: "flac", AudioCodec: "flac", Protocol: "http"},
+					},
+					CodecProfiles: []CodecProfile{
+						{
+							Type: CodecProfileTypeAudio,
+							Name: "flac",
+							Limitations: []Limitation{
+								{Name: LimitationAudioBitdepth, Comparison: ComparisonLessThanEqual, Values: []string{"16"}, Required: true},
+							},
+						},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				// DSD 1-bit → 24-bit PCM, then capped by codec profile limit to 16-bit
+				Expect(decision.TranscodeStream.BitDepth).To(Equal(16))
+				Expect(decision.TargetBitDepth).To(Equal(16))
+			})
+		})
+
+		Context("Opus fixed sample rate", func() {
+			It("sets Opus output to 48000Hz regardless of input", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2, SampleRate: 44100, BitDepth: 16}
+				ci := &ClientInfo{
+					MaxTranscodingAudioBitrate: 128,
+					TranscodingProfiles: []Profile{
+						{Container: "opus", AudioCodec: "opus", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TargetFormat).To(Equal("opus"))
+				// Opus always outputs 48000Hz
+				Expect(decision.TranscodeStream.SampleRate).To(Equal(48000))
+				Expect(decision.TargetSampleRate).To(Equal(48000))
+			})
+
+			It("sets Opus output to 48000Hz even for 96kHz input", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1500, Channels: 2, SampleRate: 96000, BitDepth: 24}
+				ci := &ClientInfo{
+					MaxTranscodingAudioBitrate: 128,
+					TranscodingProfiles: []Profile{
+						{Container: "opus", AudioCodec: "opus", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TranscodeStream.SampleRate).To(Equal(48000))
+			})
+		})
+
+		Context("Container vs format separation", func() {
+			It("preserves mp4 container when falling back to aac format", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2, SampleRate: 44100, BitDepth: 16}
+				ci := &ClientInfo{
+					MaxTranscodingAudioBitrate: 256,
+					TranscodingProfiles: []Profile{
+						{Container: "mp4", AudioCodec: "aac", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				// TargetFormat is the internal format used for DB lookup ("aac")
+				Expect(decision.TargetFormat).To(Equal("aac"))
+				// Container in the response preserves what the client asked ("mp4")
+				Expect(decision.TranscodeStream.Container).To(Equal("mp4"))
+				Expect(decision.TranscodeStream.Codec).To(Equal("aac"))
+			})
+
+			It("uses container as format when container matches transcoding config", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2, SampleRate: 44100, BitDepth: 16}
+				ci := &ClientInfo{
+					MaxTranscodingAudioBitrate: 256,
+					TranscodingProfiles: []Profile{
+						{Container: "mp3", AudioCodec: "mp3", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TargetFormat).To(Equal("mp3"))
+				Expect(decision.TranscodeStream.Container).To(Equal("mp3"))
+			})
+		})
+
+		Context("MP3 max sample rate", func() {
+			It("caps sample rate at 48000 for MP3", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1500, Channels: 2, SampleRate: 96000, BitDepth: 24}
+				ci := &ClientInfo{
+					MaxTranscodingAudioBitrate: 320,
+					TranscodingProfiles: []Profile{
+						{Container: "mp3", AudioCodec: "mp3", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TranscodeStream.SampleRate).To(Equal(48000))
+			})
+
+			It("preserves sample rate at 44100 for MP3", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2, SampleRate: 44100, BitDepth: 16}
+				ci := &ClientInfo{
+					MaxTranscodingAudioBitrate: 320,
+					TranscodingProfiles: []Profile{
+						{Container: "mp3", AudioCodec: "mp3", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				Expect(decision.TranscodeStream.SampleRate).To(Equal(44100))
+			})
+		})
+
+		Context("AAC max sample rate", func() {
+			It("caps sample rate at 96000 for AAC", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "dsf", Codec: "DSD", BitRate: 5644, Channels: 2, SampleRate: 2822400, BitDepth: 1}
+				ci := &ClientInfo{
+					MaxTranscodingAudioBitrate: 320,
+					TranscodingProfiles: []Profile{
+						{Container: "aac", AudioCodec: "aac", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanTranscode).To(BeTrue())
+				// DSD64 2822400 / 8 = 352800, capped by AAC max of 96000
+				Expect(decision.TranscodeStream.SampleRate).To(Equal(96000))
+			})
+		})
+
+		Context("Typed transcode reasons from multiple profiles", func() {
+			It("collects reasons from each failed direct play profile", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "ogg", Codec: "Vorbis", BitRate: 128, Channels: 2, SampleRate: 48000}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"flac"}, Protocols: []string{"http"}},
+						{Containers: []string{"mp3"}, AudioCodecs: []string{"mp3"}, Protocols: []string{"http"}},
+						{Containers: []string{"m4a", "mp4"}, AudioCodecs: []string{"aac"}, Protocols: []string{"http"}},
+					},
+					TranscodingProfiles: []Profile{
+						{Container: "mp3", AudioCodec: "mp3", Protocol: "http"},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.CanDirectPlay).To(BeFalse())
+				Expect(decision.TranscodeReasons).To(HaveLen(3))
+				Expect(decision.TranscodeReasons[0]).To(Equal("container not supported"))
+				Expect(decision.TranscodeReasons[1]).To(Equal("container not supported"))
+				Expect(decision.TranscodeReasons[2]).To(Equal("container not supported"))
+			})
+		})
+
+		Context("Source stream details", func() {
+			It("populates source stream correctly with kbps bitrate", func() {
+				mf := &model.MediaFile{ID: "1", Suffix: "flac", Codec: "FLAC", BitRate: 1000, Channels: 2, SampleRate: 96000, BitDepth: 24, Duration: 300.5, Size: 50000000}
+				ci := &ClientInfo{
+					DirectPlayProfiles: []DirectPlayProfile{
+						{Containers: []string{"flac"}, Protocols: []string{"http"}},
+					},
+				}
+				decision, err := svc.MakeDecision(ctx, mf, ci)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(decision.SourceStream.Container).To(Equal("flac"))
+				Expect(decision.SourceStream.Codec).To(Equal("flac"))
+				Expect(decision.SourceStream.Bitrate).To(Equal(1000)) // kbps
+				Expect(decision.SourceStream.SampleRate).To(Equal(96000))
+				Expect(decision.SourceStream.BitDepth).To(Equal(24))
+				Expect(decision.SourceStream.Channels).To(Equal(2))
+			})
+		})
+	})
+
+	Describe("Token round-trip", func() {
+		It("creates and parses a direct play token", func() {
+			decision := &Decision{
+				MediaID:       "media-123",
+				CanDirectPlay: true,
+			}
+			token, err := svc.CreateTranscodeParams(decision)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(token).ToNot(BeEmpty())
+
+			params, err := svc.ParseTranscodeParams(token)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(params.MediaID).To(Equal("media-123"))
+			Expect(params.DirectPlay).To(BeTrue())
+			Expect(params.TargetFormat).To(BeEmpty())
+		})
+
+		It("creates and parses a transcode token with kbps bitrate", func() {
+			decision := &Decision{
+				MediaID:        "media-456",
+				CanDirectPlay:  false,
+				CanTranscode:   true,
+				TargetFormat:   "mp3",
+				TargetBitrate:  256, // kbps
+				TargetChannels: 2,
+			}
+			token, err := svc.CreateTranscodeParams(decision)
+			Expect(err).ToNot(HaveOccurred())
+
+			params, err := svc.ParseTranscodeParams(token)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(params.MediaID).To(Equal("media-456"))
+			Expect(params.DirectPlay).To(BeFalse())
+			Expect(params.TargetFormat).To(Equal("mp3"))
+			Expect(params.TargetBitrate).To(Equal(256)) // kbps
+			Expect(params.TargetChannels).To(Equal(2))
+		})
+
+		It("creates and parses a transcode token with sample rate", func() {
+			decision := &Decision{
+				MediaID:          "media-789",
+				CanDirectPlay:    false,
+				CanTranscode:     true,
+				TargetFormat:     "flac",
+				TargetBitrate:    0,
+				TargetChannels:   2,
+				TargetSampleRate: 48000,
+			}
+			token, err := svc.CreateTranscodeParams(decision)
+			Expect(err).ToNot(HaveOccurred())
+
+			params, err := svc.ParseTranscodeParams(token)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(params.MediaID).To(Equal("media-789"))
+			Expect(params.DirectPlay).To(BeFalse())
+			Expect(params.TargetFormat).To(Equal("flac"))
+			Expect(params.TargetSampleRate).To(Equal(48000))
+			Expect(params.TargetChannels).To(Equal(2))
+		})
+
+		It("creates and parses a transcode token with bit depth", func() {
+			decision := &Decision{
+				MediaID:        "media-bd",
+				CanDirectPlay:  false,
+				CanTranscode:   true,
+				TargetFormat:   "flac",
+				TargetBitrate:  0,
+				TargetChannels: 2,
+				TargetBitDepth: 24,
+			}
+			token, err := svc.CreateTranscodeParams(decision)
+			Expect(err).ToNot(HaveOccurred())
+
+			params, err := svc.ParseTranscodeParams(token)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(params.MediaID).To(Equal("media-bd"))
+			Expect(params.TargetBitDepth).To(Equal(24))
+		})
+
+		It("omits bit depth from token when 0", func() {
+			decision := &Decision{
+				MediaID:        "media-nobd",
+				CanDirectPlay:  false,
+				CanTranscode:   true,
+				TargetFormat:   "mp3",
+				TargetBitrate:  256,
+				TargetBitDepth: 0,
+			}
+			token, err := svc.CreateTranscodeParams(decision)
+			Expect(err).ToNot(HaveOccurred())
+
+			params, err := svc.ParseTranscodeParams(token)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(params.TargetBitDepth).To(Equal(0))
+		})
+
+		It("omits sample rate from token when 0", func() {
+			decision := &Decision{
+				MediaID:          "media-100",
+				CanDirectPlay:    false,
+				CanTranscode:     true,
+				TargetFormat:     "mp3",
+				TargetBitrate:    256,
+				TargetSampleRate: 0,
+			}
+			token, err := svc.CreateTranscodeParams(decision)
+			Expect(err).ToNot(HaveOccurred())
+
+			params, err := svc.ParseTranscodeParams(token)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(params.TargetSampleRate).To(Equal(0))
+		})
+
+		It("rejects an invalid token", func() {
+			_, err := svc.ParseTranscodeParams("invalid-token")
+			Expect(err).To(HaveOccurred())
+		})
+	})
+})

core/transcode/types.go

@@ -0,0 +1,129 @@
+package transcode
+
+import (
+	"context"
+
+	"github.com/navidrome/navidrome/model"
+)
+
+// Decider is the core service interface for making transcoding decisions
+type Decider interface {
+	MakeDecision(ctx context.Context, mf *model.MediaFile, clientInfo *ClientInfo) (*Decision, error)
+	CreateTranscodeParams(decision *Decision) (string, error)
+	ParseTranscodeParams(token string) (*Params, error)
+}
+
+// ClientInfo represents client playback capabilities.
+// All bitrate values are in kilobits per second (kbps)
+type ClientInfo struct {
+	Name                       string
+	Platform                   string
+	MaxAudioBitrate            int
+	MaxTranscodingAudioBitrate int
+	DirectPlayProfiles         []DirectPlayProfile
+	TranscodingProfiles        []Profile
+	CodecProfiles              []CodecProfile
+}
+
+// DirectPlayProfile describes a format the client can play directly
+type DirectPlayProfile struct {
+	Containers       []string
+	AudioCodecs      []string
+	Protocols        []string
+	MaxAudioChannels int
+}
+
+// Profile describes a transcoding target the client supports
+type Profile struct {
+	Container        string
+	AudioCodec       string
+	Protocol         string
+	MaxAudioChannels int
+}
+
+// CodecProfile describes codec-specific limitations
+type CodecProfile struct {
+	Type        string
+	Name        string
+	Limitations []Limitation
+}
+
+// Limitation describes a specific codec limitation
+type Limitation struct {
+	Name       string
+	Comparison string
+	Values     []string
+	Required   bool
+}
+
+// Protocol values (OpenSubsonic spec enum)
+const (
+	ProtocolHTTP = "http"
+	ProtocolHLS  = "hls"
+)
+
+// Comparison operators (OpenSubsonic spec enum)
+const (
+	ComparisonEquals           = "Equals"
+	ComparisonNotEquals        = "NotEquals"
+	ComparisonLessThanEqual    = "LessThanEqual"
+	ComparisonGreaterThanEqual = "GreaterThanEqual"
+)
+
+// Limitation names (OpenSubsonic spec enum)
+const (
+	LimitationAudioChannels   = "audioChannels"
+	LimitationAudioBitrate    = "audioBitrate"
+	LimitationAudioProfile    = "audioProfile"
+	LimitationAudioSamplerate = "audioSamplerate"
+	LimitationAudioBitdepth   = "audioBitdepth"
+)
+
+// Codec profile types (OpenSubsonic spec enum)
+const (
+	CodecProfileTypeAudio = "AudioCodec"
+)
+
+// Decision represents the internal decision result.
+// All bitrate values are in kilobits per second (kbps).
+type Decision struct {
+	MediaID          string
+	CanDirectPlay    bool
+	CanTranscode     bool
+	TranscodeReasons []string
+	ErrorReason      string
+	TargetFormat     string
+	TargetBitrate    int
+	TargetChannels   int
+	TargetSampleRate int
+	TargetBitDepth   int
+	SourceStream     StreamDetails
+	TranscodeStream  *StreamDetails
+}
+
+// StreamDetails describes audio stream properties.
+// Bitrate is in kilobits per second (kbps).
+type StreamDetails struct {
+	Container  string
+	Codec      string
+	Profile    string // Audio profile (e.g., "LC", "HE-AAC"). Empty until scanner support is added.
+	Bitrate    int
+	SampleRate int
+	BitDepth   int
+	Channels   int
+	Duration   float32
+	Size       int64
+	IsLossless bool
+}
+
+// Params contains the parameters extracted from a transcode token.
+// TargetBitrate is in kilobits per second (kbps).
+type Params struct {
+	MediaID          string
+	DirectPlay       bool
+	TargetFormat     string
+	TargetBitrate    int
+	TargetChannels   int
+	TargetSampleRate int
+	TargetBitDepth   int
+}

core/user.go

@@ -50,12 +50,12 @@ type userRepositoryWrapper struct {
 }
 
 // Save implements rest.Persistable by delegating to the underlying repository.
-func (r *userRepositoryWrapper) Save(entity interface{}) (string, error) {
+func (r *userRepositoryWrapper) Save(entity any) (string, error) {
 	return r.UserRepository.(rest.Persistable).Save(entity)
 }
 
 // Update implements rest.Persistable by delegating to the underlying repository.
-func (r *userRepositoryWrapper) Update(id string, entity interface{}, cols ...string) error {
+func (r *userRepositoryWrapper) Update(id string, entity any, cols ...string) error {
 	return r.UserRepository.(rest.Persistable).Update(id, entity, cols...)
 }
 

core/wire_providers.go

@@ -8,6 +8,7 @@ import (
 	"github.com/navidrome/navidrome/core/metrics"
 	"github.com/navidrome/navidrome/core/playback"
 	"github.com/navidrome/navidrome/core/scrobbler"
+	"github.com/navidrome/navidrome/core/transcode"
 )
 
 var Set = wire.NewSet(
@@ -20,6 +21,7 @@ var Set = wire.NewSet(
 	NewLibrary,
 	NewUser,
 	NewMaintenance,
+	transcode.NewDecider,
 	agents.GetAgents,
 	external.NewProvider,
 	wire.Bind(new(external.Agents), new(*agents.Agents)),

db/db.go

@@ -126,7 +126,7 @@ func Optimize(ctx context.Context) {
 	}
 	log.Debug(ctx, "Optimizing open connections", "numConns", numConns)
 	var conns []*sql.Conn
-	for i := 0; i < numConns; i++ {
+	for range numConns {
 		conn, err := Db().Conn(ctx)
 		conns = append(conns, conn)
 		if err != nil {
@@ -147,8 +147,8 @@ func Optimize(ctx context.Context) {
 
 type statusLogger struct{ numPending int }
 
-func (*statusLogger) Fatalf(format string, v ...interface{}) { log.Fatal(fmt.Sprintf(format, v...)) }
-func (l *statusLogger) Printf(format string, v ...interface{}) {
+func (*statusLogger) Fatalf(format string, v ...any) { log.Fatal(fmt.Sprintf(format, v...)) }
+func (l *statusLogger) Printf(format string, v ...any) {
 	if len(v) < 1 {
 		return
 	}
@@ -183,27 +183,27 @@ type logAdapter struct {
 	silent bool
 }
 
-func (l *logAdapter) Fatal(v ...interface{}) {
+func (l *logAdapter) Fatal(v ...any) {
 	log.Fatal(l.ctx, fmt.Sprint(v...))
 }
 
-func (l *logAdapter) Fatalf(format string, v ...interface{}) {
+func (l *logAdapter) Fatalf(format string, v ...any) {
 	log.Fatal(l.ctx, fmt.Sprintf(format, v...))
 }
 
-func (l *logAdapter) Print(v ...interface{}) {
+func (l *logAdapter) Print(v ...any) {
 	if !l.silent {
 		log.Info(l.ctx, fmt.Sprint(v...))
 	}
 }
 
-func (l *logAdapter) Println(v ...interface{}) {
+func (l *logAdapter) Println(v ...any) {
 	if !l.silent {
 		log.Info(l.ctx, fmt.Sprintln(v...))
 	}
 }
 
-func (l *logAdapter) Printf(format string, v ...interface{}) {
+func (l *logAdapter) Printf(format string, v ...any) {
 	if !l.silent {
 		log.Info(l.ctx, fmt.Sprintf(format, v...))
 	}

db/migrations/20260205120000_add_codec_and_update_transcodings.go

@@ -0,0 +1,63 @@
+package migrations
+
+import (
+	"context"
+	"database/sql"
+
+	"github.com/navidrome/navidrome/model/id"
+	"github.com/pressly/goose/v3"
+)
+
+func init() {
+	goose.AddMigrationContext(upAddCodecAndUpdateTranscodings, downAddCodecAndUpdateTranscodings)
+}
+
+func upAddCodecAndUpdateTranscodings(_ context.Context, tx *sql.Tx) error {
+	// Add codec column to media_file.
+	_, err := tx.Exec(`ALTER TABLE media_file ADD COLUMN codec VARCHAR(255) DEFAULT '' NOT NULL`)
+	if err != nil {
+		return err
+	}
+	_, err = tx.Exec(`CREATE INDEX IF NOT EXISTS media_file_codec ON media_file(codec)`)
+	if err != nil {
+		return err
+	}
+
+	// Update old AAC default (adts) to new default (ipod with fragmented MP4).
+	// Only affects users who still have the unmodified old default command.
+	_, err = tx.Exec(
+		`UPDATE transcoding SET command = ? WHERE target_format = 'aac' AND command = ?`,
+		"ffmpeg -i %s -ss %t -map 0:a:0 -b:a %bk -v 0 -c:a aac -f ipod -movflags frag_keyframe+empty_moov -",
+		"ffmpeg -i %s -ss %t -map 0:a:0 -b:a %bk -v 0 -c:a aac -f adts -",
+	)
+	if err != nil {
+		return err
+	}
+
+	// Add FLAC transcoding for existing installations that were seeded before FLAC was added.
+	var count int
+	err = tx.QueryRow("SELECT COUNT(*) FROM transcoding WHERE target_format = 'flac'").Scan(&count)
+	if err != nil {
+		return err
+	}
+	if count == 0 {
+		_, err = tx.Exec(
+			"INSERT INTO transcoding (id, name, target_format, default_bit_rate, command) VALUES (?, ?, ?, ?, ?)",
+			id.NewRandom(), "flac audio", "flac", 0,
+			"ffmpeg -i %s -ss %t -map 0:a:0 -v 0 -c:a flac -f flac -",
+		)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func downAddCodecAndUpdateTranscodings(_ context.Context, tx *sql.Tx) error {
+	_, err := tx.Exec(`DROP INDEX IF EXISTS media_file_codec`)
+	if err != nil {
+		return err
+	}
+	_, err = tx.Exec(`ALTER TABLE media_file DROP COLUMN codec`)
+	return err
+}

go.mod

@@ -7,14 +7,14 @@ replace (
 	github.com/dhowden/tag v0.0.0-20240417053706-3d75831295e8 => github.com/deluan/tag v0.0.0-20241002021117-dfe5e6ea396d
 
 	// Fork to implement raw tags support
-	go.senan.xyz/taglib => github.com/deluan/go-taglib v0.0.0-20260119020817-8753c7531798
+	go.senan.xyz/taglib => github.com/deluan/go-taglib v0.0.0-20260205042457-5d80806aee57
 )
 
 require (
 	github.com/Masterminds/squirrel v1.5.4
 	github.com/RaveNoX/go-jsoncommentstrip v1.0.0
 	github.com/andybalholm/cascadia v1.3.3
-	github.com/bmatcuk/doublestar/v4 v4.9.2
+	github.com/bmatcuk/doublestar/v4 v4.10.0
 	github.com/bradleyjkemp/cupaloy/v2 v2.8.0
 	github.com/deluan/rest v0.0.0-20211102003136-6260bc399cbf
 	github.com/deluan/sanitize v0.0.0-20241120162836-fdfd8fdfaa55
@@ -28,7 +28,7 @@ require (
 	github.com/dustin/go-humanize v1.0.1
 	github.com/extism/go-sdk v1.7.1
 	github.com/fatih/structs v1.1.0
-	github.com/go-chi/chi/v5 v5.2.4
+	github.com/go-chi/chi/v5 v5.2.5
 	github.com/go-chi/cors v1.2.2
 	github.com/go-chi/httprate v0.15.0
 	github.com/go-chi/jwtauth/v5 v5.3.3
@@ -49,8 +49,8 @@ require (
 	github.com/mattn/go-sqlite3 v1.14.33
 	github.com/microcosm-cc/bluemonday v1.0.27
 	github.com/mileusna/useragent v1.3.5
-	github.com/onsi/ginkgo/v2 v2.27.5
-	github.com/onsi/gomega v1.39.0
+	github.com/onsi/ginkgo/v2 v2.28.1
+	github.com/onsi/gomega v1.39.1
 	github.com/pelletier/go-toml/v2 v2.2.4
 	github.com/pocketbase/dbx v1.11.0
 	github.com/pressly/goose/v3 v3.26.0
@@ -98,7 +98,7 @@ require (
 	github.com/goccy/go-json v0.10.5 // indirect
 	github.com/goccy/go-yaml v1.19.2 // indirect
 	github.com/google/go-cmp v0.7.0 // indirect
-	github.com/google/pprof v0.0.0-20260115054156-294ebfa9ad83 // indirect
+	github.com/google/pprof v0.0.0-20260202012954-cb029daf43ef // indirect
 	github.com/google/subcommands v1.2.0 // indirect
 	github.com/gorilla/css v1.0.1 // indirect
 	github.com/hashicorp/errwrap v1.1.0 // indirect
@@ -134,7 +134,7 @@ require (
 	github.com/stretchr/objx v0.5.3 // indirect
 	github.com/subosito/gotenv v1.6.0 // indirect
 	github.com/tetratelabs/wabin v0.0.0-20230304001439-f6f874872834 // indirect
-	github.com/zeebo/xxh3 v1.0.2 // indirect
+	github.com/zeebo/xxh3 v1.1.0 // indirect
 	go.opentelemetry.io/proto/otlp v1.9.0 // indirect
 	go.uber.org/multierr v1.11.0 // indirect
 	go.yaml.in/yaml/v2 v2.4.3 // indirect

go.sum

@@ -16,8 +16,8 @@ github.com/aymerick/douceur v0.2.0 h1:Mv+mAeH1Q+n9Fr+oyamOlAkUNPWPlA8PPGR0QAaYuP
 github.com/aymerick/douceur v0.2.0/go.mod h1:wlT5vV2O3h55X9m7iVYN0TBM0NH/MmbLnd30/FjWUq4=
 github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
 github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
-github.com/bmatcuk/doublestar/v4 v4.9.2 h1:b0mc6WyRSYLjzofB2v/0cuDUZ+MqoGyH3r0dVij35GI=
-github.com/bmatcuk/doublestar/v4 v4.9.2/go.mod h1:xBQ8jztBU6kakFMg+8WGxn0c6z1fTSPVIjEY1Wr7jzc=
+github.com/bmatcuk/doublestar/v4 v4.10.0 h1:zU9WiOla1YA122oLM6i4EXvGW62DvKZVxIe6TYWexEs=
+github.com/bmatcuk/doublestar/v4 v4.10.0/go.mod h1:xBQ8jztBU6kakFMg+8WGxn0c6z1fTSPVIjEY1Wr7jzc=
 github.com/bradleyjkemp/cupaloy/v2 v2.8.0 h1:any4BmKE+jGIaMpnU8YgH/I2LPiLBufr6oMMlVBbn9M=
 github.com/bradleyjkemp/cupaloy/v2 v2.8.0/go.mod h1:bm7JXdkRd4BHJk9HpwqAI8BoAY1lps46Enkdqw6aRX0=
 github.com/cespare/reflex v0.3.1 h1:N4Y/UmRrjwOkNT0oQQnYsdr6YBxvHqtSfPB4mqOyAKk=
@@ -36,8 +36,8 @@ github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc h1:U9qPSI2PIWSS1
 github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/decred/dcrd/dcrec/secp256k1/v4 v4.4.0 h1:NMZiJj8QnKe1LgsbDayM4UoHwbvwDRwnI3hwNaAHRnc=
 github.com/decred/dcrd/dcrec/secp256k1/v4 v4.4.0/go.mod h1:ZXNYxsqcloTdSy/rNShjYzMhyjf0LaoftYK0p+A3h40=
-github.com/deluan/go-taglib v0.0.0-20260119020817-8753c7531798 h1:q4fvcIK/LxElpyQILCejG6WPYjVb2F/4P93+k017ANk=
-github.com/deluan/go-taglib v0.0.0-20260119020817-8753c7531798/go.mod h1:sKDN0U4qXDlq6LFK+aOAkDH4Me5nDV1V/A4B+B69xBA=
+github.com/deluan/go-taglib v0.0.0-20260205042457-5d80806aee57 h1:SXIwfjzTv0UzoUWpFREl8p3AxXVLmbcto1/ISih11a0=
+github.com/deluan/go-taglib v0.0.0-20260205042457-5d80806aee57/go.mod h1:sKDN0U4qXDlq6LFK+aOAkDH4Me5nDV1V/A4B+B69xBA=
 github.com/deluan/rest v0.0.0-20211102003136-6260bc399cbf h1:tb246l2Zmpt/GpF9EcHCKTtwzrd0HGfEmoODFA/qnk4=
 github.com/deluan/rest v0.0.0-20211102003136-6260bc399cbf/go.mod h1:tSgDythFsl0QgS/PFWfIZqcJKnkADWneY80jaVRlqK8=
 github.com/deluan/sanitize v0.0.0-20241120162836-fdfd8fdfaa55 h1:wSCnggTs2f2ji6nFwQmfwgINcmSMj0xF0oHnoyRSPe4=
@@ -77,8 +77,8 @@ github.com/gkampitakis/go-diff v1.3.2 h1:Qyn0J9XJSDTgnsgHRdz9Zp24RaJeKMUHg2+PDZZ
 github.com/gkampitakis/go-diff v1.3.2/go.mod h1:LLgOrpqleQe26cte8s36HTWcTmMEur6OPYerdAAS9tk=
 github.com/gkampitakis/go-snaps v0.5.15 h1:amyJrvM1D33cPHwVrjo9jQxX8g/7E2wYdZ+01KS3zGE=
 github.com/gkampitakis/go-snaps v0.5.15/go.mod h1:HNpx/9GoKisdhw9AFOBT1N7DBs9DiHo/hGheFGBZ+mc=
-github.com/go-chi/chi/v5 v5.2.4 h1:WtFKPHwlywe8Srng8j2BhOD9312j9cGUxG1SP4V2cR4=
-github.com/go-chi/chi/v5 v5.2.4/go.mod h1:X7Gx4mteadT3eDOMTsXzmI4/rwUpOwBHLpAfupzFJP0=
+github.com/go-chi/chi/v5 v5.2.5 h1:Eg4myHZBjyvJmAFjFvWgrqDTXFyOzjj7YIm3L3mu6Ug=
+github.com/go-chi/chi/v5 v5.2.5/go.mod h1:X7Gx4mteadT3eDOMTsXzmI4/rwUpOwBHLpAfupzFJP0=
 github.com/go-chi/cors v1.2.2 h1:Jmey33TE+b+rB7fT8MUy1u0I4L+NARQlK6LhzKPSyQE=
 github.com/go-chi/cors v1.2.2/go.mod h1:sSbTewc+6wYHBBCW7ytsFSn836hqM7JxpglAy2Vzc58=
 github.com/go-chi/httprate v0.15.0 h1:j54xcWV9KGmPf/X4H32/aTH+wBlrvxL7P+SdnRqxh5g=
@@ -110,8 +110,8 @@ github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
 github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
 github.com/google/go-pipeline v0.0.0-20230411140531-6cbedfc1d3fc h1:hd+uUVsB1vdxohPneMrhGH2YfQuH5hRIK9u4/XCeUtw=
 github.com/google/go-pipeline v0.0.0-20230411140531-6cbedfc1d3fc/go.mod h1:SL66SJVysrh7YbDCP9tH30b8a9o/N2HeiQNUm85EKhc=
-github.com/google/pprof v0.0.0-20260115054156-294ebfa9ad83 h1:z2ogiKUYzX5Is6zr/vP9vJGqPwcdqsWjOt+V8J7+bTc=
-github.com/google/pprof v0.0.0-20260115054156-294ebfa9ad83/go.mod h1:MxpfABSjhmINe3F1It9d+8exIHFvUqtLIRCdOGNXqiI=
+github.com/google/pprof v0.0.0-20260202012954-cb029daf43ef h1:xpF9fUHpoIrrjX24DURVKiwHcFpw19ndIs+FwTSMbno=
+github.com/google/pprof v0.0.0-20260202012954-cb029daf43ef/go.mod h1:MxpfABSjhmINe3F1It9d+8exIHFvUqtLIRCdOGNXqiI=
 github.com/google/subcommands v1.2.0 h1:vWQspBTo2nEqTUFita5/KeEWlUL8kQObDFbub/EN9oE=
 github.com/google/subcommands v1.2.0/go.mod h1:ZjhPrFU+Olkh9WazFPsl27BQ4UPiG37m3yTrtFlrHVk=
 github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
@@ -197,10 +197,10 @@ github.com/ncruces/go-strftime v0.1.9 h1:bY0MQC28UADQmHmaF5dgpLmImcShSi2kHU9XLdh
 github.com/ncruces/go-strftime v0.1.9/go.mod h1:Fwc5htZGVVkseilnfgOVb9mKy6w1naJmn9CehxcKcls=
 github.com/ogier/pflag v0.0.1 h1:RW6JSWSu/RkSatfcLtogGfFgpim5p7ARQ10ECk5O750=
 github.com/ogier/pflag v0.0.1/go.mod h1:zkFki7tvTa0tafRvTBIZTvzYyAu6kQhPZFnshFFPE+g=
-github.com/onsi/ginkgo/v2 v2.27.5 h1:ZeVgZMx2PDMdJm/+w5fE/OyG6ILo1Y3e+QX4zSR0zTE=
-github.com/onsi/ginkgo/v2 v2.27.5/go.mod h1:ArE1D/XhNXBXCBkKOLkbsb2c81dQHCRcF5zwn/ykDRo=
-github.com/onsi/gomega v1.39.0 h1:y2ROC3hKFmQZJNFeGAMeHZKkjBL65mIZcvrLQBF9k6Q=
-github.com/onsi/gomega v1.39.0/go.mod h1:ZCU1pkQcXDO5Sl9/VVEGlDyp+zm0m1cmeG5TOzLgdh4=
+github.com/onsi/ginkgo/v2 v2.28.1 h1:S4hj+HbZp40fNKuLUQOYLDgZLwNUVn19N3Atb98NCyI=
+github.com/onsi/ginkgo/v2 v2.28.1/go.mod h1:CLtbVInNckU3/+gC8LzkGUb9oF+e8W8TdUsxPwvdOgE=
+github.com/onsi/gomega v1.39.1 h1:1IJLAad4zjPn2PsnhH70V4DKRFlrCzGBNrNaru+Vf28=
+github.com/onsi/gomega v1.39.1/go.mod h1:hL6yVALoTOxeWudERyfppUcZXjMwIMLnuSfruD2lcfg=
 github.com/pelletier/go-toml/v2 v2.2.4 h1:mye9XuhQ6gvn5h28+VilKrrPoQVanw5PMw/TB0t5Ec4=
 github.com/pelletier/go-toml/v2 v2.2.4/go.mod h1:2gIqNv+qfxSVS7cM2xJQKtLSTLUE9V8t9Stt+h56mCY=
 github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e/go.mod h1:pJLUxLENpZxwdsKMEsNbx1VGcRFpLqf3715MtcvvzbA=
@@ -301,8 +301,8 @@ github.com/xrash/smetrics v0.0.0-20250705151800-55b8f293f342/go.mod h1:Ohn+xnUBi
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
 github.com/zeebo/assert v1.3.0 h1:g7C04CbJuIDKNPFHmsk4hwZDO5O+kntRxzaUoNXj+IQ=
 github.com/zeebo/assert v1.3.0/go.mod h1:Pq9JiuJQpG8JLJdtkwrJESF0Foym2/D9XMU5ciN/wJ0=
-github.com/zeebo/xxh3 v1.0.2 h1:xZmwmqxHZA8AI603jOQ0tMqmBr9lPeFwGg6d+xy9DC0=
-github.com/zeebo/xxh3 v1.0.2/go.mod h1:5NWz9Sef7zIDm2JHfFlcQvNekmcEl9ekUZQQKCYaDcA=
+github.com/zeebo/xxh3 v1.1.0 h1:s7DLGDK45Dyfg7++yxI0khrfwq9661w9EN78eP/UZVs=
+github.com/zeebo/xxh3 v1.1.0/go.mod h1:IisAie1LELR4xhVinxWS5+zf1lA4p0MW4T+w+W07F5s=
 go.opentelemetry.io/proto/otlp v1.9.0 h1:l706jCMITVouPOqEnii2fIAuO3IVGBRPV5ICjceRb/A=
 go.opentelemetry.io/proto/otlp v1.9.0/go.mod h1:xE+Cx5E/eEHw+ISFkwPLwCZefwVjY+pqKg1qcK03+/4=
 go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=

log/log.go

@@ -19,7 +19,7 @@ import (
 
 type Level uint32
 
-type LevelFunc = func(ctx interface{}, msg interface{}, keyValuePairs ...interface{})
+type LevelFunc = func(ctx any, msg any, keyValuePairs ...any)
 
 var redacted = &Hook{
 	AcceptedLevels: logrus.AllLevels,
@@ -152,7 +152,7 @@ func Redact(msg string) string {
 	return r
 }
 
-func NewContext(ctx context.Context, keyValuePairs ...interface{}) context.Context {
+func NewContext(ctx context.Context, keyValuePairs ...any) context.Context {
 	if ctx == nil {
 		ctx = context.Background()
 	}
@@ -184,32 +184,32 @@ func IsGreaterOrEqualTo(level Level) bool {
 	return shouldLog(level, 2)
 }
 
-func Fatal(args ...interface{}) {
+func Fatal(args ...any) {
 	Log(LevelFatal, args...)
 	os.Exit(1)
 }
 
-func Error(args ...interface{}) {
+func Error(args ...any) {
 	Log(LevelError, args...)
 }
 
-func Warn(args ...interface{}) {
+func Warn(args ...any) {
 	Log(LevelWarn, args...)
 }
 
-func Info(args ...interface{}) {
+func Info(args ...any) {
 	Log(LevelInfo, args...)
 }
 
-func Debug(args ...interface{}) {
+func Debug(args ...any) {
 	Log(LevelDebug, args...)
 }
 
-func Trace(args ...interface{}) {
+func Trace(args ...any) {
 	Log(LevelTrace, args...)
 }
 
-func Log(level Level, args ...interface{}) {
+func Log(level Level, args ...any) {
 	if !shouldLog(level, 3) {
 		return
 	}
@@ -250,7 +250,7 @@ func shouldLog(requiredLevel Level, skip int) bool {
 	return false
 }
 
-func parseArgs(args []interface{}) (*logrus.Entry, string) {
+func parseArgs(args []any) (*logrus.Entry, string) {
 	var l *logrus.Entry
 	var err error
 	if args[0] == nil {
@@ -289,7 +289,7 @@ func parseArgs(args []interface{}) (*logrus.Entry, string) {
 	return l, ""
 }
 
-func addFields(logger *logrus.Entry, keyValuePairs []interface{}) *logrus.Entry {
+func addFields(logger *logrus.Entry, keyValuePairs []any) *logrus.Entry {
 	for i := 0; i < len(keyValuePairs); i += 2 {
 		switch name := keyValuePairs[i].(type) {
 		case error:
@@ -316,7 +316,7 @@ func addFields(logger *logrus.Entry, keyValuePairs []interface{}) *logrus.Entry
 	return logger
 }
 
-func extractLogger(ctx interface{}) (*logrus.Entry, error) {
+func extractLogger(ctx any) (*logrus.Entry, error) {
 	switch ctx := ctx.(type) {
 	case *logrus.Entry:
 		return ctx, nil

model/datastore.go

@@ -41,7 +41,7 @@ type DataStore interface {
 	Scrobble(ctx context.Context) ScrobbleRepository
 	Plugin(ctx context.Context) PluginRepository
 
-	Resource(ctx context.Context, model interface{}) ResourceRepository
+	Resource(ctx context.Context, model any) ResourceRepository
 
 	WithTx(block func(tx DataStore) error, scope ...string) error
 	WithTxImmediate(block func(tx DataStore) error, scope ...string) error

model/get_entity.go

@@ -5,7 +5,7 @@ import (
 )
 
 // TODO: Should the type be encoded in the ID?
-func GetEntityByID(ctx context.Context, ds DataStore, id string) (interface{}, error) {
+func GetEntityByID(ctx context.Context, ds DataStore, id string) (any, error) {
 	ar, err := ds.Artist(ctx).Get(id)
 	if err == nil {
 		return ar, nil

model/mediafile.go

@@ -14,6 +14,7 @@ import (
 
 	"github.com/gohugoio/hashstructure"
 	"github.com/navidrome/navidrome/conf"
+	confmime "github.com/navidrome/navidrome/conf/mime"
 	"github.com/navidrome/navidrome/consts"
 	"github.com/navidrome/navidrome/utils"
 	"github.com/navidrome/navidrome/utils/slice"
@@ -56,6 +57,7 @@ type MediaFile struct {
 	SampleRate           int      `structs:"sample_rate" json:"sampleRate"`
 	BitDepth             int      `structs:"bit_depth" json:"bitDepth"`
 	Channels             int      `structs:"channels" json:"channels"`
+	Codec                string   `structs:"codec" json:"codec"`
 	Genre                string   `structs:"genre" json:"genre"`
 	Genres               Genres   `structs:"-" json:"genres,omitempty"`
 	SortTitle            string   `structs:"sort_title" json:"sortTitle,omitempty"`
@@ -140,7 +142,7 @@ func (mf MediaFile) Hash() string {
 	}
 	hash, _ := hashstructure.Hash(mf, opts)
 	sum := md5.New()
-	sum.Write([]byte(fmt.Sprintf("%d", hash)))
+	sum.Write(fmt.Appendf(nil, "%d", hash))
 	sum.Write(mf.Tags.Hash())
 	sum.Write(mf.Participants.Hash())
 	return fmt.Sprintf("%x", sum.Sum(nil))
@@ -161,6 +163,79 @@ func (mf MediaFile) AbsolutePath() string {
 	return filepath.Join(mf.LibraryPath, mf.Path)
 }
 
+// AudioCodec returns the audio codec for this file.
+// Uses the stored Codec field if available, otherwise infers from Suffix and audio properties.
+func (mf MediaFile) AudioCodec() string {
+	// If we have a stored codec from scanning, normalize and return it
+	if mf.Codec != "" {
+		return strings.ToLower(mf.Codec)
+	}
+	// Fallback: infer from Suffix + BitDepth
+	return mf.inferCodecFromSuffix()
+}
+
+// inferCodecFromSuffix infers the codec from the file extension when Codec field is empty.
+func (mf MediaFile) inferCodecFromSuffix() string {
+	switch strings.ToLower(mf.Suffix) {
+	case "mp3", "mpga":
+		return "mp3"
+	case "mp2":
+		return "mp2"
+	case "ogg", "oga":
+		return "vorbis"
+	case "opus":
+		return "opus"
+	case "mpc":
+		return "mpc"
+	case "wma":
+		return "wma"
+	case "flac":
+		return "flac"
+	case "wav":
+		return "pcm"
+	case "aif", "aiff", "aifc":
+		return "pcm"
+	case "ape":
+		return "ape"
+	case "wv", "wvp":
+		return "wv"
+	case "tta":
+		return "tta"
+	case "tak":
+		return "tak"
+	case "shn":
+		return "shn"
+	case "dsf", "dff":
+		return "dsd"
+	case "m4a":
+		// AAC if BitDepth==0, ALAC if BitDepth>0
+		if mf.BitDepth > 0 {
+			return "alac"
+		}
+		return "aac"
+	case "m4b", "m4p", "m4r":
+		return "aac"
+	default:
+		return ""
+	}
+}
+
+// IsLossless returns true if this file uses a lossless codec.
+func (mf MediaFile) IsLossless() bool {
+	codec := mf.AudioCodec()
+	// Primary: codec-based check (most accurate for containers like M4A)
+	switch codec {
+	case "flac", "alac", "pcm", "ape", "wv", "tta", "tak", "shn", "dsd":
+		return true
+	}
+	// Secondary: suffix-based check using configurable list from YAML
+	if slices.Contains(confmime.LosslessFormats, mf.Suffix) {
+		return true
+	}
+	// Fallback heuristic: if BitDepth is set, it's likely lossless
+	return mf.BitDepth > 0
+}
+
 type MediaFiles []MediaFile
 
 // ToAlbum creates an Album object based on the attributes of this MediaFiles collection.

model/mediafile_test.go

@@ -475,7 +475,7 @@ var _ = Describe("MediaFile", func() {
 		DeferCleanup(configtest.SetupConfig())
 		conf.Server.EnableMediaFileCoverArt = true
 	})
-	Describe(".CoverArtId()", func() {
+	Describe("CoverArtId", func() {
 		It("returns its own id if it HasCoverArt", func() {
 			mf := MediaFile{ID: "111", AlbumID: "1", HasCoverArt: true}
 			id := mf.CoverArtID()
@@ -496,6 +496,94 @@ var _ = Describe("MediaFile", func() {
 			Expect(id.ID).To(Equal(mf.AlbumID))
 		})
 	})
+
+	Describe("AudioCodec", func() {
+		It("returns normalized stored codec when available", func() {
+			mf := MediaFile{Codec: "AAC", Suffix: "m4a"}
+			Expect(mf.AudioCodec()).To(Equal("aac"))
+		})
+
+		It("returns stored codec lowercased", func() {
+			mf := MediaFile{Codec: "ALAC", Suffix: "m4a"}
+			Expect(mf.AudioCodec()).To(Equal("alac"))
+		})
+
+		DescribeTable("infers codec from suffix when Codec field is empty",
+			func(suffix string, bitDepth int, expected string) {
+				mf := MediaFile{Suffix: suffix, BitDepth: bitDepth}
+				Expect(mf.AudioCodec()).To(Equal(expected))
+			},
+			Entry("mp3", "mp3", 0, "mp3"),
+			Entry("mpga", "mpga", 0, "mp3"),
+			Entry("mp2", "mp2", 0, "mp2"),
+			Entry("ogg", "ogg", 0, "vorbis"),
+			Entry("oga", "oga", 0, "vorbis"),
+			Entry("opus", "opus", 0, "opus"),
+			Entry("mpc", "mpc", 0, "mpc"),
+			Entry("wma", "wma", 0, "wma"),
+			Entry("flac", "flac", 0, "flac"),
+			Entry("wav", "wav", 0, "pcm"),
+			Entry("aif", "aif", 0, "pcm"),
+			Entry("aiff", "aiff", 0, "pcm"),
+			Entry("aifc", "aifc", 0, "pcm"),
+			Entry("ape", "ape", 0, "ape"),
+			Entry("wv", "wv", 0, "wv"),
+			Entry("wvp", "wvp", 0, "wv"),
+			Entry("tta", "tta", 0, "tta"),
+			Entry("tak", "tak", 0, "tak"),
+			Entry("shn", "shn", 0, "shn"),
+			Entry("dsf", "dsf", 0, "dsd"),
+			Entry("dff", "dff", 0, "dsd"),
+			Entry("m4a with BitDepth=0 (AAC)", "m4a", 0, "aac"),
+			Entry("m4a with BitDepth>0 (ALAC)", "m4a", 16, "alac"),
+			Entry("m4b", "m4b", 0, "aac"),
+			Entry("m4p", "m4p", 0, "aac"),
+			Entry("m4r", "m4r", 0, "aac"),
+			Entry("unknown suffix", "xyz", 0, ""),
+		)
+
+		It("prefers stored codec over suffix inference", func() {
+			mf := MediaFile{Codec: "ALAC", Suffix: "m4a", BitDepth: 0}
+			Expect(mf.AudioCodec()).To(Equal("alac"))
+		})
+	})
+
+	Describe("IsLossless", func() {
+		BeforeEach(func() {
+			DeferCleanup(configtest.SetupConfig())
+		})
+
+		DescribeTable("detects lossless codecs",
+			func(codec string, suffix string, bitDepth int, expected bool) {
+				mf := MediaFile{Codec: codec, Suffix: suffix, BitDepth: bitDepth}
+				Expect(mf.IsLossless()).To(Equal(expected))
+			},
+			Entry("flac", "FLAC", "flac", 16, true),
+			Entry("alac", "ALAC", "m4a", 24, true),
+			Entry("pcm via wav", "", "wav", 16, true),
+			Entry("pcm via aiff", "", "aiff", 24, true),
+			Entry("ape", "", "ape", 16, true),
+			Entry("wv", "", "wv", 0, true),
+			Entry("tta", "", "tta", 0, true),
+			Entry("tak", "", "tak", 0, true),
+			Entry("shn", "", "shn", 0, true),
+			Entry("dsd", "", "dsf", 0, true),
+			Entry("mp3 is lossy", "MP3", "mp3", 0, false),
+			Entry("aac is lossy", "AAC", "m4a", 0, false),
+			Entry("vorbis is lossy", "", "ogg", 0, false),
+			Entry("opus is lossy", "", "opus", 0, false),
+		)
+
+		It("detects lossless via BitDepth fallback when codec is unknown", func() {
+			mf := MediaFile{Suffix: "xyz", BitDepth: 24}
+			Expect(mf.IsLossless()).To(BeTrue())
+		})
+
+		It("returns false for unknown with no BitDepth", func() {
+			mf := MediaFile{Suffix: "xyz", BitDepth: 0}
+			Expect(mf.IsLossless()).To(BeFalse())
+		})
+	})
 })
 
 func t(v string) time.Time {

model/metadata/map_mediafile.go

@@ -65,6 +65,7 @@ func (md Metadata) ToMediaFile(libID int, folderID string) model.MediaFile {
 	mf.SampleRate = md.AudioProperties().SampleRate
 	mf.BitDepth = md.AudioProperties().BitDepth
 	mf.Channels = md.AudioProperties().Channels
+	mf.Codec = md.AudioProperties().Codec
 	mf.Path = md.FilePath()
 	mf.Suffix = md.Suffix()
 	mf.Size = md.Size()

model/metadata/metadata.go

@@ -35,6 +35,7 @@ type AudioProperties struct {
 	BitDepth   int
 	SampleRate int
 	Channels   int
+	Codec      string
 }
 
 type Date string
@@ -250,7 +251,15 @@ func processPairMapping(name model.TagName, mapping model.TagConf, lowered model
 	id3Base := parseID3Pairs(name, lowered)
 
 	if len(aliasValues) > 0 {
-		id3Base = append(id3Base, parseVorbisPairs(aliasValues)...)
+		// For lyrics, don't use parseVorbisPairs as parentheses in lyrics content
+		// should not be interpreted as language keys (e.g. "(intro)" is not a language)
+		if name == model.TagLyrics {
+			for _, v := range aliasValues {
+				id3Base = append(id3Base, NewPair("xxx", v))
+			}
+		} else {
+			id3Base = append(id3Base, parseVorbisPairs(aliasValues)...)
+		}
 	}
 	return id3Base
 }
@@ -260,8 +269,8 @@ func parseID3Pairs(name model.TagName, lowered model.Tags) []string {
 	prefix := string(name) + ":"
 	for tagKey, tagValues := range lowered {
 		keyStr := string(tagKey)
-		if strings.HasPrefix(keyStr, prefix) {
-			keyPart := strings.TrimPrefix(keyStr, prefix)
+		if after, ok := strings.CutPrefix(keyStr, prefix); ok {
+			keyPart := after
 			if keyPart == string(name) {
 				keyPart = ""
 			}

model/metadata/metadata_test.go

@@ -246,6 +246,18 @@ var _ = Describe("Metadata", func() {
 					metadata.NewPair("eng", "Lyrics"),
 				))
 			})
+
+			It("should preserve lyrics starting with parentheses from alias tags", func() {
+				props.Tags = model.RawTags{
+					"LYRICS": {"(line one)\nline two\nline three"},
+				}
+				md = metadata.New(filePath, props)
+
+				Expect(md.All()).To(HaveKey(model.TagLyrics))
+				Expect(md.Strings(model.TagLyrics)).To(ContainElements(
+					metadata.NewPair("xxx", "(line one)\nline two\nline three"),
+				))
+			})
 		})
 
 		Describe("ReplayGain", func() {

model/metadata/persistent_ids.go

@@ -49,8 +49,8 @@ func createGetPID(hash hashFunc) getPIDFunc {
 	}
 	getPID = func(mf model.MediaFile, md Metadata, spec string, prependLibId bool) string {
 		pid := ""
-		fields := strings.Split(spec, "|")
-		for _, field := range fields {
+		fields := strings.SplitSeq(spec, "|")
+		for field := range fields {
 			attributes := strings.Split(field, ",")
 			hasValue := false
 			values := slice.Map(attributes, func(attr string) string {

model/scanner.go

@@ -51,13 +51,13 @@ func ParseTargets(libFolders []string) ([]ScanTarget, error) {
 		}
 
 		// Split by the first colon
-		colonIdx := strings.Index(part, ":")
-		if colonIdx == -1 {
+		before, after, ok := strings.Cut(part, ":")
+		if !ok {
 			return nil, fmt.Errorf("invalid target format: %q (expected libraryID:folderPath)", part)
 		}
 
-		libIDStr := part[:colonIdx]
-		folderPath := part[colonIdx+1:]
+		libIDStr := before
+		folderPath := after
 
 		libID, err := strconv.Atoi(libIDStr)
 		if err != nil {

model/share.go

@@ -22,8 +22,8 @@ type Share struct {
 	Format        string     `structs:"format" json:"format,omitempty"`
 	MaxBitRate    int        `structs:"max_bit_rate" json:"maxBitRate,omitempty"`
 	VisitCount    int        `structs:"visit_count" json:"visitCount,omitempty"`
-	CreatedAt     time.Time  `structs:"created_at" json:"createdAt,omitempty"`
-	UpdatedAt     time.Time  `structs:"updated_at" json:"updatedAt,omitempty"`
+	CreatedAt     time.Time  `structs:"created_at" json:"createdAt"`
+	UpdatedAt     time.Time  `structs:"updated_at" json:"updatedAt"`
 	Tracks        MediaFiles `structs:"-" json:"tracks,omitempty"`
 	Albums        Albums     `structs:"-" json:"albums,omitempty"`
 	URL           string     `structs:"-" json:"-"`

model/tag.go

@@ -144,10 +144,8 @@ func (t Tags) Merge(tags Tags) {
 }
 
 func (t Tags) Add(name TagName, v string) {
-	for _, existing := range t[name] {
-		if existing == v {
-			return
-		}
+	if slices.Contains(t[name], v) {
+		return
 	}
 	t[name] = append(t[name], v)
 }

persistence/album_repository.go

@@ -145,11 +145,11 @@ func recentlyAddedSort() string {
 	return "created_at"
 }
 
-func recentlyPlayedFilter(string, interface{}) Sqlizer {
+func recentlyPlayedFilter(string, any) Sqlizer {
 	return Gt{"play_count": 0}
 }
 
-func yearFilter(_ string, value interface{}) Sqlizer {
+func yearFilter(_ string, value any) Sqlizer {
 	return Or{
 		And{
 			Gt{"min_year": 0},
@@ -160,14 +160,14 @@ func yearFilter(_ string, value interface{}) Sqlizer {
 	}
 }
 
-func artistFilter(_ string, value interface{}) Sqlizer {
+func artistFilter(_ string, value any) Sqlizer {
 	return Or{
 		Exists("json_tree(participants, '$.albumartist')", Eq{"value": value}),
 		Exists("json_tree(participants, '$.artist')", Eq{"value": value}),
 	}
 }
 
-func artistRoleFilter(name string, value interface{}) Sqlizer {
+func artistRoleFilter(name string, value any) Sqlizer {
 	roleName := strings.TrimSuffix(strings.TrimPrefix(name, "role_"), "_id")
 
 	// Check if the role name is valid. If not, return an invalid filter
@@ -177,7 +177,7 @@ func artistRoleFilter(name string, value interface{}) Sqlizer {
 	return Exists(fmt.Sprintf("json_tree(participants, '$.%s')", roleName), Eq{"value": value})
 }
 
-func allRolesFilter(_ string, value interface{}) Sqlizer {
+func allRolesFilter(_ string, value any) Sqlizer {
 	return Like{"participants": fmt.Sprintf(`%%"%s"%%`, value)}
 }
 
@@ -248,7 +248,7 @@ func (r *albumRepository) CopyAttributes(fromID, toID string, columns ...string)
 	if err != nil {
 		return fmt.Errorf("getting album to copy fields from: %w", err)
 	}
-	to := make(map[string]interface{})
+	to := make(map[string]any)
 	for _, col := range columns {
 		to[col] = from[col]
 	}
@@ -370,11 +370,11 @@ func (r *albumRepository) Count(options ...rest.QueryOptions) (int64, error) {
 	return r.CountAll(r.parseRestOptions(r.ctx, options...))
 }
 
-func (r *albumRepository) Read(id string) (interface{}, error) {
+func (r *albumRepository) Read(id string) (any, error) {
 	return r.Get(id)
 }
 
-func (r *albumRepository) ReadAll(options ...rest.QueryOptions) (interface{}, error) {
+func (r *albumRepository) ReadAll(options ...rest.QueryOptions) (any, error) {
 	return r.GetAll(r.parseRestOptions(r.ctx, options...))
 }
 
@@ -382,7 +382,7 @@ func (r *albumRepository) EntityName() string {
 	return "album"
 }
 
-func (r *albumRepository) NewInstance() interface{} {
+func (r *albumRepository) NewInstance() any {
 	return &model.Album{}
 }
 

persistence/album_repository_test.go

@@ -162,7 +162,7 @@ var _ = Describe("AlbumRepository", func() {
 
 				newID := id.NewRandom()
 				Expect(albumRepo.Put(&model.Album{LibraryID: 1, ID: newID, Name: "name", SongCount: songCount})).To(Succeed())
-				for i := 0; i < playCount; i++ {
+				for range playCount {
 					Expect(albumRepo.IncPlayCount(newID, time.Now())).To(Succeed())
 				}
 
@@ -185,7 +185,7 @@ var _ = Describe("AlbumRepository", func() {
 
 				newID := id.NewRandom()
 				Expect(albumRepo.Put(&model.Album{LibraryID: 1, ID: newID, Name: "name", SongCount: songCount})).To(Succeed())
-				for i := 0; i < playCount; i++ {
+				for range playCount {
 					Expect(albumRepo.IncPlayCount(newID, time.Now())).To(Succeed())
 				}
 
@@ -406,7 +406,7 @@ var _ = Describe("AlbumRepository", func() {
 				sql, args, err := sqlizer.ToSql()
 				Expect(err).ToNot(HaveOccurred())
 				Expect(sql).To(Equal(expectedSQL))
-				Expect(args).To(Equal([]interface{}{artistID}))
+				Expect(args).To(Equal([]any{artistID}))
 			},
 			Entry("artist role", "role_artist_id", "123",
 				"exists (select 1 from json_tree(participants, '$.artist') where value = ?)"),
@@ -428,7 +428,7 @@ var _ = Describe("AlbumRepository", func() {
 				sql, args, err := sqlizer.ToSql()
 				Expect(err).ToNot(HaveOccurred())
 				Expect(sql).To(Equal(fmt.Sprintf("exists (select 1 from json_tree(participants, '$.%s') where value = ?)", roleName)))
-				Expect(args).To(Equal([]interface{}{"test-id"}))
+				Expect(args).To(Equal([]any{"test-id"}))
 			}
 		})
 

persistence/artist_repository.go

@@ -164,7 +164,7 @@ func roleFilter(_ string, role any) Sqlizer {
 }
 
 // artistLibraryIdFilter filters artists based on library access through the library_artist table
-func artistLibraryIdFilter(_ string, value interface{}) Sqlizer {
+func artistLibraryIdFilter(_ string, value any) Sqlizer {
 	return Eq{"library_artist.library_id": value}
 }
 
@@ -534,11 +534,11 @@ func (r *artistRepository) Count(options ...rest.QueryOptions) (int64, error) {
 	return r.CountAll(r.parseRestOptions(r.ctx, options...))
 }
 
-func (r *artistRepository) Read(id string) (interface{}, error) {
+func (r *artistRepository) Read(id string) (any, error) {
 	return r.Get(id)
 }
 
-func (r *artistRepository) ReadAll(options ...rest.QueryOptions) (interface{}, error) {
+func (r *artistRepository) ReadAll(options ...rest.QueryOptions) (any, error) {
 	role := "total"
 	if len(options) > 0 {
 		if v, ok := options[0].Filters["role"].(string); ok {
@@ -555,7 +555,7 @@ func (r *artistRepository) EntityName() string {
 	return "artist"
 }
 
-func (r *artistRepository) NewInstance() interface{} {
+func (r *artistRepository) NewInstance() any {
 	return &model.Artist{}
 }
 

persistence/folder_repository.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"maps"
 	"os"
 	"path/filepath"
 	"slices"
@@ -117,9 +118,7 @@ func (r folderRepository) GetFolderUpdateInfo(lib model.Library, targetPaths ...
 		if err != nil {
 			return nil, err
 		}
-		for id, info := range batchResult {
-			result[id] = info
-		}
+		maps.Copy(result, batchResult)
 	}
 
 	return result, nil

persistence/genre_repository.go

@@ -33,18 +33,18 @@ func (r *genreRepository) GetAll(opt ...model.QueryOptions) (model.Genres, error
 
 // Override ResourceRepository methods to return Genre objects instead of Tag objects
 
-func (r *genreRepository) Read(id string) (interface{}, error) {
+func (r *genreRepository) Read(id string) (any, error) {
 	sel := r.selectGenre().Where(Eq{"tag.id": id})
 	var res model.Genre
 	err := r.queryOne(sel, &res)
 	return &res, err
 }
 
-func (r *genreRepository) ReadAll(options ...rest.QueryOptions) (interface{}, error) {
+func (r *genreRepository) ReadAll(options ...rest.QueryOptions) (any, error) {
 	return r.GetAll(r.parseRestOptions(r.ctx, options...))
 }
 
-func (r *genreRepository) NewInstance() interface{} {
+func (r *genreRepository) NewInstance() any {
 	return &model.Genre{}
 }
 

persistence/genre_repository_test.go

@@ -182,7 +182,7 @@ var _ = Describe("GenreRepository", func() {
 		It("should filter by name using like match", func() {
 			// Test filtering by partial name match using the "name" filter which maps to containsFilter("tag_value")
 			options := rest.QueryOptions{
-				Filters: map[string]interface{}{"name": "%rock%"},
+				Filters: map[string]any{"name": "%rock%"},
 			}
 			count, err := restRepo.Count(options)
 			Expect(err).ToNot(HaveOccurred())
@@ -289,7 +289,7 @@ var _ = Describe("GenreRepository", func() {
 			It("should allow headless processes to apply explicit library_id filters", func() {
 				// Filter by specific library
 				genres, err := headlessRestRepo.ReadAll(rest.QueryOptions{
-					Filters: map[string]interface{}{"library_id": 2},
+					Filters: map[string]any{"library_id": 2},
 				})
 				Expect(err).ToNot(HaveOccurred())
 

persistence/helpers.go

@@ -15,7 +15,7 @@ type PostMapper interface {
 	PostMapArgs(map[string]any) error
 }
 
-func toSQLArgs(rec interface{}) (map[string]interface{}, error) {
+func toSQLArgs(rec any) (map[string]any, error) {
 	m := structs.Map(rec)
 	for k, v := range m {
 		switch t := v.(type) {
@@ -71,7 +71,7 @@ type existsCond struct {
 	not      bool
 }
 
-func (e existsCond) ToSql() (string, []interface{}, error) {
+func (e existsCond) ToSql() (string, []any, error) {
 	sql, args, err := e.cond.ToSql()
 	sql = fmt.Sprintf("exists (select 1 from %s where %s)", e.subTable, sql)
 	if e.not {

persistence/library_repository.go

@@ -305,7 +305,7 @@ func (r *libraryRepository) Count(options ...rest.QueryOptions) (int64, error) {
 	return r.CountAll(r.parseRestOptions(r.ctx, options...))
 }
 
-func (r *libraryRepository) Read(id string) (interface{}, error) {
+func (r *libraryRepository) Read(id string) (any, error) {
 	idInt, err := strconv.Atoi(id)
 	if err != nil {
 		log.Trace(r.ctx, "invalid library id: %s", id, err)
@@ -314,7 +314,7 @@ func (r *libraryRepository) Read(id string) (interface{}, error) {
 	return r.Get(idInt)
 }
 
-func (r *libraryRepository) ReadAll(options ...rest.QueryOptions) (interface{}, error) {
+func (r *libraryRepository) ReadAll(options ...rest.QueryOptions) (any, error) {
 	return r.GetAll(r.parseRestOptions(r.ctx, options...))
 }
 
@@ -322,11 +322,11 @@ func (r *libraryRepository) EntityName() string {
 	return "library"
 }
 
-func (r *libraryRepository) NewInstance() interface{} {
+func (r *libraryRepository) NewInstance() any {
 	return &model.Library{}
 }
 
-func (r *libraryRepository) Save(entity interface{}) (string, error) {
+func (r *libraryRepository) Save(entity any) (string, error) {
 	lib := entity.(*model.Library)
 	lib.ID = 0 // Reset ID to ensure we create a new library
 	err := r.Put(lib)
@@ -336,7 +336,7 @@ func (r *libraryRepository) Save(entity interface{}) (string, error) {
 	return strconv.Itoa(lib.ID), nil
 }
 
-func (r *libraryRepository) Update(id string, entity interface{}, cols ...string) error {
+func (r *libraryRepository) Update(id string, entity any, cols ...string) error {
 	lib := entity.(*model.Library)
 	idInt, err := strconv.Atoi(id)
 	if err != nil {

persistence/mediafile_repository.go

@@ -443,11 +443,11 @@ func (r *mediaFileRepository) Count(options ...rest.QueryOptions) (int64, error)
 	return r.CountAll(r.parseRestOptions(r.ctx, options...))
 }
 
-func (r *mediaFileRepository) Read(id string) (interface{}, error) {
+func (r *mediaFileRepository) Read(id string) (any, error) {
 	return r.Get(id)
 }
 
-func (r *mediaFileRepository) ReadAll(options ...rest.QueryOptions) (interface{}, error) {
+func (r *mediaFileRepository) ReadAll(options ...rest.QueryOptions) (any, error) {
 	return r.GetAll(r.parseRestOptions(r.ctx, options...))
 }
 
@@ -455,7 +455,7 @@ func (r *mediaFileRepository) EntityName() string {
 	return "mediafile"
 }
 
-func (r *mediaFileRepository) NewInstance() interface{} {
+func (r *mediaFileRepository) NewInstance() any {
 	return &model.MediaFile{}
 }
 

persistence/mediafile_repository_test.go

@@ -310,7 +310,7 @@ var _ = Describe("MediaRepository", func() {
 
 				// Update "Old Song": created long ago, updated recently
 				_, err := db.Update("media_file",
-					map[string]interface{}{
+					map[string]any{
 						"created_at": oldTime,
 						"updated_at": newTime,
 					},
@@ -319,7 +319,7 @@ var _ = Describe("MediaRepository", func() {
 
 				// Update "Middle Song": created and updated at the same middle time
 				_, err = db.Update("media_file",
-					map[string]interface{}{
+					map[string]any{
 						"created_at": middleTime,
 						"updated_at": middleTime,
 					},
@@ -328,7 +328,7 @@ var _ = Describe("MediaRepository", func() {
 
 				// Update "New Song": created recently, updated long ago
 				_, err = db.Update("media_file",
-					map[string]interface{}{
+					map[string]any{
 						"created_at": newTime,
 						"updated_at": oldTime,
 					},

persistence/persistence.go

@@ -97,7 +97,7 @@ func (s *SQLStore) Plugin(ctx context.Context) model.PluginRepository {
 	return NewPluginRepository(ctx, s.getDBXBuilder())
 }
 
-func (s *SQLStore) Resource(ctx context.Context, m interface{}) model.ResourceRepository {
+func (s *SQLStore) Resource(ctx context.Context, m any) model.ResourceRepository {
 	switch m.(type) {
 	case model.User:
 		return s.User(ctx).(model.ResourceRepository)

persistence/player_repository.go

@@ -103,14 +103,14 @@ func (r *playerRepository) Count(options ...rest.QueryOptions) (int64, error) {
 	return r.CountAll(r.parseRestOptions(r.ctx, options...))
 }
 
-func (r *playerRepository) Read(id string) (interface{}, error) {
+func (r *playerRepository) Read(id string) (any, error) {
 	sel := r.newRestSelect().Where(Eq{"player.id": id})
 	var res model.Player
 	err := r.queryOne(sel, &res)
 	return &res, err
 }
 
-func (r *playerRepository) ReadAll(options ...rest.QueryOptions) (interface{}, error) {
+func (r *playerRepository) ReadAll(options ...rest.QueryOptions) (any, error) {
 	sel := r.newRestSelect(r.parseRestOptions(r.ctx, options...))
 	res := model.Players{}
 	err := r.queryAll(sel, &res)
@@ -121,7 +121,7 @@ func (r *playerRepository) EntityName() string {
 	return "player"
 }
 
-func (r *playerRepository) NewInstance() interface{} {
+func (r *playerRepository) NewInstance() any {
 	return &model.Player{}
 }
 
@@ -130,7 +130,7 @@ func (r *playerRepository) isPermitted(p *model.Player) bool {
 	return u.IsAdmin || p.UserId == u.ID
 }
 
-func (r *playerRepository) Save(entity interface{}) (string, error) {
+func (r *playerRepository) Save(entity any) (string, error) {
 	t := entity.(*model.Player)
 	if !r.isPermitted(t) {
 		return "", rest.ErrPermissionDenied
@@ -142,7 +142,7 @@ func (r *playerRepository) Save(entity interface{}) (string, error) {
 	return id, err
 }
 
-func (r *playerRepository) Update(id string, entity interface{}, cols ...string) error {
+func (r *playerRepository) Update(id string, entity any, cols ...string) error {
 	t := entity.(*model.Player)
 	t.ID = id
 	if !r.isPermitted(t) {

persistence/playlist_repository.go

@@ -61,14 +61,14 @@ func NewPlaylistRepository(ctx context.Context, db dbx.Builder) model.PlaylistRe
 	return r
 }
 
-func playlistFilter(_ string, value interface{}) Sqlizer {
+func playlistFilter(_ string, value any) Sqlizer {
 	return Or{
 		substringFilter("playlist.name", value),
 		substringFilter("playlist.comment", value),
 	}
 }
 
-func smartPlaylistFilter(string, interface{}) Sqlizer {
+func smartPlaylistFilter(string, any) Sqlizer {
 	return Or{
 		Eq{"rules": ""},
 		Eq{"rules": nil},
@@ -285,13 +285,16 @@ func (r *playlistRepository) refreshSmartPlaylist(pls *model.Playlist) bool {
 	}
 
 	// Update when the playlist was last refreshed (for cache purposes)
-	updSql := Update(r.tableName).Set("evaluated_at", time.Now()).Where(Eq{"id": pls.ID})
+	now := time.Now()
+	updSql := Update(r.tableName).Set("evaluated_at", now).Where(Eq{"id": pls.ID})
 	_, err = r.executeSQL(updSql)
 	if err != nil {
 		log.Error(r.ctx, "Error updating smart playlist", "playlist", pls.Name, "id", pls.ID, err)
 		return false
 	}
 
+	pls.EvaluatedAt = &now
+
 	log.Debug(r.ctx, "Refreshed playlist", "playlist", pls.Name, "id", pls.ID, "numTracks", pls.SongCount, "elapsed", time.Since(start))
 
 	return true
@@ -418,11 +421,11 @@ func (r *playlistRepository) Count(options ...rest.QueryOptions) (int64, error)
 	return r.CountAll(r.parseRestOptions(r.ctx, options...))
 }
 
-func (r *playlistRepository) Read(id string) (interface{}, error) {
+func (r *playlistRepository) Read(id string) (any, error) {
 	return r.Get(id)
 }
 
-func (r *playlistRepository) ReadAll(options ...rest.QueryOptions) (interface{}, error) {
+func (r *playlistRepository) ReadAll(options ...rest.QueryOptions) (any, error) {
 	return r.GetAll(r.parseRestOptions(r.ctx, options...))
 }
 
@@ -430,11 +433,11 @@ func (r *playlistRepository) EntityName() string {
 	return "playlist"
 }
 
-func (r *playlistRepository) NewInstance() interface{} {
+func (r *playlistRepository) NewInstance() any {
 	return &model.Playlist{}
 }
 
-func (r *playlistRepository) Save(entity interface{}) (string, error) {
+func (r *playlistRepository) Save(entity any) (string, error) {
 	pls := entity.(*model.Playlist)
 	pls.OwnerID = loggedUser(r.ctx).ID
 	pls.ID = "" // Make sure we don't override an existing playlist
@@ -445,7 +448,7 @@ func (r *playlistRepository) Save(entity interface{}) (string, error) {
 	return pls.ID, err
 }
 
-func (r *playlistRepository) Update(id string, entity interface{}, cols ...string) error {
+func (r *playlistRepository) Update(id string, entity any, cols ...string) error {
 	pls := dbPlaylist{Playlist: *entity.(*model.Playlist)}
 	current, err := r.Get(id)
 	if err != nil {

persistence/playlist_repository_test.go

@@ -4,6 +4,7 @@ import (
 	"time"
 
 	"github.com/navidrome/navidrome/conf"
+	"github.com/navidrome/navidrome/conf/configtest"
 	"github.com/navidrome/navidrome/log"
 	"github.com/navidrome/navidrome/model"
 	"github.com/navidrome/navidrome/model/criteria"
@@ -160,14 +161,23 @@ var _ = Describe("PlaylistRepository", func() {
 			})
 		})
 
-		// TODO Validate these tests
-		XContext("child smart playlists", func() {
-			When("refresh day has expired", func() {
+		Context("child smart playlists", func() {
+			BeforeEach(func() {
+				DeferCleanup(configtest.SetupConfig())
+			})
+
+			When("refresh delay has expired", func() {
 				It("should refresh tracks for smart playlist referenced in parent smart playlist criteria", func() {
 					conf.Server.SmartPlaylistRefreshDelay = -1 * time.Second
 
-					nestedPls := model.Playlist{Name: "Nested", OwnerID: "userid", Rules: rules}
+					childRules := &criteria.Criteria{
+						Expression: criteria.All{
+							criteria.Contains{"title": "Day"},
+						},
+					}
+					nestedPls := model.Playlist{Name: "Nested", OwnerID: "userid", Public: true, Rules: childRules}
 					Expect(repo.Put(&nestedPls)).To(Succeed())
+					DeferCleanup(func() { _ = repo.Delete(nestedPls.ID) })
 
 					parentPls := model.Playlist{Name: "Parent", OwnerID: "userid", Rules: &criteria.Criteria{
 						Expression: criteria.All{
@@ -175,45 +185,69 @@ var _ = Describe("PlaylistRepository", func() {
 						},
 					}}
 					Expect(repo.Put(&parentPls)).To(Succeed())
+					DeferCleanup(func() { _ = repo.Delete(parentPls.ID) })
 
+					// Nested playlist has not been evaluated yet
 					nestedPlsRead, err := repo.Get(nestedPls.ID)
 					Expect(err).ToNot(HaveOccurred())
+					Expect(nestedPlsRead.EvaluatedAt).To(BeNil())
 
-					_, err = repo.GetWithTracks(parentPls.ID, true, false)
+					// Getting parent with refresh should recursively refresh the nested playlist
+					pls, err := repo.GetWithTracks(parentPls.ID, true, false)
 					Expect(err).ToNot(HaveOccurred())
+					Expect(pls.EvaluatedAt).ToNot(BeNil())
+					Expect(*pls.EvaluatedAt).To(BeTemporally("~", time.Now(), 2*time.Second))
 
-					// Check that the nested playlist was refreshed by parent get by verifying evaluatedAt is updated since first nestedPls get
+					// Parent should have tracks from the nested playlist
+					Expect(pls.Tracks).To(HaveLen(1))
+					Expect(pls.Tracks[0].MediaFileID).To(Equal(songDayInALife.ID))
+
+					// Nested playlist should now have been refreshed (EvaluatedAt set)
 					nestedPlsAfterParentGet, err := repo.Get(nestedPls.ID)
 					Expect(err).ToNot(HaveOccurred())
-
-					Expect(*nestedPlsAfterParentGet.EvaluatedAt).To(BeTemporally(">", *nestedPlsRead.EvaluatedAt))
+					Expect(nestedPlsAfterParentGet.EvaluatedAt).ToNot(BeNil())
+					Expect(*nestedPlsAfterParentGet.EvaluatedAt).To(BeTemporally("~", time.Now(), 2*time.Second))
 				})
 			})
 
-			When("refresh day has not expired", func() {
+			When("refresh delay has not expired", func() {
 				It("should NOT refresh tracks for smart playlist referenced in parent smart playlist criteria", func() {
 					conf.Server.SmartPlaylistRefreshDelay = 1 * time.Hour
+					childEvaluatedAt := time.Now().Add(-30 * time.Minute)
 
-					nestedPls := model.Playlist{Name: "Nested", OwnerID: "userid", Rules: rules}
+					childRules := &criteria.Criteria{
+						Expression: criteria.All{
+							criteria.Contains{"title": "Day"},
+						},
+					}
+					nestedPls := model.Playlist{Name: "Nested", OwnerID: "userid", Public: true, Rules: childRules, EvaluatedAt: &childEvaluatedAt}
 					Expect(repo.Put(&nestedPls)).To(Succeed())
+					DeferCleanup(func() { _ = repo.Delete(nestedPls.ID) })
 
+					// Parent has no EvaluatedAt, so it WILL refresh, but the child should not
 					parentPls := model.Playlist{Name: "Parent", OwnerID: "userid", Rules: &criteria.Criteria{
 						Expression: criteria.All{
 							criteria.InPlaylist{"id": nestedPls.ID},
 						},
 					}}
 					Expect(repo.Put(&parentPls)).To(Succeed())
+					DeferCleanup(func() { _ = repo.Delete(parentPls.ID) })
 
 					nestedPlsRead, err := repo.Get(nestedPls.ID)
 					Expect(err).ToNot(HaveOccurred())
 
-					_, err = repo.GetWithTracks(parentPls.ID, true, false)
+					// Getting parent with refresh should NOT recursively refresh the nested playlist
+					parent, err := repo.GetWithTracks(parentPls.ID, true, false)
 					Expect(err).ToNot(HaveOccurred())
 
-					// Check that the nested playlist was not refreshed by parent get by verifying evaluatedAt is not updated since first nestedPls get
+					// Parent should have been refreshed (its EvaluatedAt was nil)
+					Expect(parent.EvaluatedAt).ToNot(BeNil())
+					Expect(*parent.EvaluatedAt).To(BeTemporally("~", time.Now(), 2*time.Second))
+
+					// Nested playlist should NOT have been refreshed (still within delay window)
 					nestedPlsAfterParentGet, err := repo.Get(nestedPls.ID)
 					Expect(err).ToNot(HaveOccurred())
-
+					Expect(*nestedPlsAfterParentGet.EvaluatedAt).To(BeTemporally("~", childEvaluatedAt, time.Second))
 					Expect(*nestedPlsAfterParentGet.EvaluatedAt).To(Equal(*nestedPlsRead.EvaluatedAt))
 				})
 			})

persistence/playlist_track_repository.go

@@ -84,7 +84,7 @@ func (r *playlistTrackRepository) Count(options ...rest.QueryOptions) (int64, er
 	return r.count(query, r.parseRestOptions(r.ctx, options...))
 }
 
-func (r *playlistTrackRepository) Read(id string) (interface{}, error) {
+func (r *playlistTrackRepository) Read(id string) (any, error) {
 	userID := loggedUser(r.ctx).ID
 	sel := r.newSelect().
 		LeftJoin("annotation on ("+
@@ -128,7 +128,7 @@ func (r *playlistTrackRepository) GetAlbumIDs(options ...model.QueryOptions) ([]
 	return ids, nil
 }
 
-func (r *playlistTrackRepository) ReadAll(options ...rest.QueryOptions) (interface{}, error) {
+func (r *playlistTrackRepository) ReadAll(options ...rest.QueryOptions) (any, error) {
 	return r.GetAll(r.parseRestOptions(r.ctx, options...))
 }
 
@@ -136,7 +136,7 @@ func (r *playlistTrackRepository) EntityName() string {
 	return "playlist_tracks"
 }
 
-func (r *playlistTrackRepository) NewInstance() interface{} {
+func (r *playlistTrackRepository) NewInstance() any {
 	return &model.PlaylistTrack{}
 }
 

persistence/playqueue_repository.go

@@ -122,8 +122,8 @@ func (r *playQueueRepository) toModel(pq *playQueue) model.PlayQueue {
 		UpdatedAt: pq.UpdatedAt,
 	}
 	if strings.TrimSpace(pq.Items) != "" {
-		tracks := strings.Split(pq.Items, ",")
-		for _, t := range tracks {
+		tracks := strings.SplitSeq(pq.Items, ",")
+		for t := range tracks {
 			q.Items = append(q.Items, model.MediaFile{ID: t})
 		}
 	}

persistence/radio_repository.go

@@ -63,7 +63,7 @@ func (r *radioRepository) Put(radio *model.Radio) error {
 		return rest.ErrPermissionDenied
 	}
 
-	var values map[string]interface{}
+	var values map[string]any
 
 	radio.UpdatedAt = time.Now()
 
@@ -97,19 +97,19 @@ func (r *radioRepository) EntityName() string {
 	return "radio"
 }
 
-func (r *radioRepository) NewInstance() interface{} {
+func (r *radioRepository) NewInstance() any {
 	return &model.Radio{}
 }
 
-func (r *radioRepository) Read(id string) (interface{}, error) {
+func (r *radioRepository) Read(id string) (any, error) {
 	return r.Get(id)
 }
 
-func (r *radioRepository) ReadAll(options ...rest.QueryOptions) (interface{}, error) {
+func (r *radioRepository) ReadAll(options ...rest.QueryOptions) (any, error) {
 	return r.GetAll(r.parseRestOptions(r.ctx, options...))
 }
 
-func (r *radioRepository) Save(entity interface{}) (string, error) {
+func (r *radioRepository) Save(entity any) (string, error) {
 	t := entity.(*model.Radio)
 	if !r.isPermitted() {
 		return "", rest.ErrPermissionDenied
@@ -121,7 +121,7 @@ func (r *radioRepository) Save(entity interface{}) (string, error) {
 	return t.ID, err
 }
 
-func (r *radioRepository) Update(id string, entity interface{}, cols ...string) error {
+func (r *radioRepository) Update(id string, entity any, cols ...string) error {
 	t := entity.(*model.Radio)
 	t.ID = id
 	if !r.isPermitted() {

persistence/scrobble_buffer_repository.go

@@ -51,7 +51,7 @@ func (r *scrobbleBufferRepository) UserIDs(service string) ([]string, error) {
 }
 
 func (r *scrobbleBufferRepository) Enqueue(service, userId, mediaFileId string, playTime time.Time) error {
-	ins := Insert(r.tableName).SetMap(map[string]interface{}{
+	ins := Insert(r.tableName).SetMap(map[string]any{
 		"id":            id.NewRandom(),
 		"user_id":       userId,
 		"service":       service,

persistence/scrobble_buffer_repository_test.go

@@ -24,7 +24,7 @@ var _ = Describe("ScrobbleBufferRepository", func() {
 		id := id.NewRandom()
 		ids = append(ids, id)
 
-		ins := squirrel.Insert("scrobble_buffer").SetMap(map[string]interface{}{
+		ins := squirrel.Insert("scrobble_buffer").SetMap(map[string]any{
 			"id":            id,
 			"user_id":       userId,
 			"service":       service,

persistence/scrobble_repository.go

@@ -23,7 +23,7 @@ func NewScrobbleRepository(ctx context.Context, db dbx.Builder) model.ScrobbleRe
 
 func (r *scrobbleRepository) RecordScrobble(mediaFileID string, submissionTime time.Time) error {
 	userID := loggedUser(r.ctx).ID
-	values := map[string]interface{}{
+	values := map[string]any{
 		"media_file_id":   mediaFileID,
 		"user_id":         userID,
 		"submission_time": submissionTime.Unix(),

persistence/share_repository.go

@@ -138,7 +138,7 @@ func sortByIdPosition(mfs model.MediaFiles, ids []string) model.MediaFiles {
 	return sorted
 }
 
-func (r *shareRepository) Update(id string, entity interface{}, cols ...string) error {
+func (r *shareRepository) Update(id string, entity any, cols ...string) error {
 	s := entity.(*model.Share)
 	// TODO Validate record
 	s.ID = id
@@ -151,7 +151,7 @@ func (r *shareRepository) Update(id string, entity interface{}, cols ...string)
 	return err
 }
 
-func (r *shareRepository) Save(entity interface{}) (string, error) {
+func (r *shareRepository) Save(entity any) (string, error) {
 	s := entity.(*model.Share)
 	// TODO Validate record
 	u := loggedUser(r.ctx)
@@ -179,18 +179,18 @@ func (r *shareRepository) EntityName() string {
 	return "share"
 }
 
-func (r *shareRepository) NewInstance() interface{} {
+func (r *shareRepository) NewInstance() any {
 	return &model.Share{}
 }
 
-func (r *shareRepository) Read(id string) (interface{}, error) {
+func (r *shareRepository) Read(id string) (any, error) {
 	sel := r.selectShare().Where(Eq{"share.id": id})
 	var res model.Share
 	err := r.queryOne(sel, &res)
 	return &res, err
 }
 
-func (r *shareRepository) ReadAll(options ...rest.QueryOptions) (interface{}, error) {
+func (r *shareRepository) ReadAll(options ...rest.QueryOptions) (any, error) {
 	sq := r.selectShare(r.parseRestOptions(r.ctx, options...))
 	res := model.Shares{}
 	err := r.queryAll(sq, &res)

persistence/share_repository_test.go

@@ -47,7 +47,7 @@ var _ = Describe("ShareRepository", func() {
 				_, err := GetDBXBuilder().NewQuery(`
 					INSERT INTO share (id, user_id, description, resource_type, resource_ids, created_at, updated_at) 
 					VALUES ({:id}, {:user}, {:desc}, {:type}, {:ids}, {:created}, {:updated})
-				`).Bind(map[string]interface{}{
+				`).Bind(map[string]any{
 					"id":      shareID,
 					"user":    adminUser.ID,
 					"desc":    "Headless Test Share",
@@ -79,7 +79,7 @@ var _ = Describe("ShareRepository", func() {
 				_, err := GetDBXBuilder().NewQuery(`
 					INSERT INTO share (id, user_id, description, resource_type, resource_ids, created_at, updated_at) 
 					VALUES ({:id}, {:user}, {:desc}, {:type}, {:ids}, {:created}, {:updated})
-				`).Bind(map[string]interface{}{
+				`).Bind(map[string]any{
 					"id":      shareID,
 					"user":    adminUser.ID,
 					"desc":    "Headless Get Share",
@@ -110,7 +110,7 @@ var _ = Describe("ShareRepository", func() {
 			_, err := GetDBXBuilder().NewQuery(`
 				INSERT INTO share (id, user_id, description, resource_type, resource_ids, created_at, updated_at) 
 				VALUES ({:id}, {:user}, {:desc}, {:type}, {:ids}, {:created}, {:updated})
-			`).Bind(map[string]interface{}{
+			`).Bind(map[string]any{
 				"id":      shareID,
 				"user":    adminUser.ID,
 				"desc":    "SQL Test Share",

persistence/sql_annotations.go

@@ -66,7 +66,7 @@ func (r sqlRepository) annId(itemID ...string) And {
 	}
 }
 
-func (r sqlRepository) annUpsert(values map[string]interface{}, itemIDs ...string) error {
+func (r sqlRepository) annUpsert(values map[string]any, itemIDs ...string) error {
 	upd := Update(annotationTable).Where(r.annId(itemIDs...))
 	for f, v := range values {
 		upd = upd.Set(f, v)
@@ -90,12 +90,12 @@ func (r sqlRepository) annUpsert(values map[string]interface{}, itemIDs ...strin
 
 func (r sqlRepository) SetStar(starred bool, ids ...string) error {
 	starredAt := time.Now()
-	return r.annUpsert(map[string]interface{}{"starred": starred, "starred_at": starredAt}, ids...)
+	return r.annUpsert(map[string]any{"starred": starred, "starred_at": starredAt}, ids...)
 }
 
 func (r sqlRepository) SetRating(rating int, itemID string) error {
 	ratedAt := time.Now()
-	err := r.annUpsert(map[string]interface{}{"rating": rating, "rated_at": ratedAt}, itemID)
+	err := r.annUpsert(map[string]any{"rating": rating, "rated_at": ratedAt}, itemID)
 	if err != nil {
 		return err
 	}
@@ -121,7 +121,7 @@ func (r sqlRepository) IncPlayCount(itemID string, ts time.Time) error {
 
 	if c == 0 || errors.Is(err, sql.ErrNoRows) {
 		userID := loggedUser(r.ctx).ID
-		values := map[string]interface{}{}
+		values := map[string]any{}
 		values["user_id"] = userID
 		values["item_type"] = r.tableName
 		values["item_id"] = itemID

persistence/sql_annotations_test.go

@@ -32,17 +32,17 @@ var _ = Describe("Annotation Filters", func() {
 
 	Describe("annotationBoolFilter", func() {
 		DescribeTable("creates correct SQL expressions",
-			func(field, value string, expectedSQL string, expectedArgs []interface{}) {
+			func(field, value string, expectedSQL string, expectedArgs []any) {
 				sqlizer := annotationBoolFilter(field)(field, value)
 				sql, args, err := sqlizer.ToSql()
 				Expect(err).ToNot(HaveOccurred())
 				Expect(sql).To(Equal(expectedSQL))
 				Expect(args).To(Equal(expectedArgs))
 			},
-			Entry("starred=true", "starred", "true", "COALESCE(starred, 0) > 0", []interface{}(nil)),
-			Entry("starred=false", "starred", "false", "COALESCE(starred, 0) = 0", []interface{}(nil)),
-			Entry("starred=True (case insensitive)", "starred", "True", "COALESCE(starred, 0) > 0", []interface{}(nil)),
-			Entry("rating=true", "rating", "true", "COALESCE(rating, 0) > 0", []interface{}(nil)),
+			Entry("starred=true", "starred", "true", "COALESCE(starred, 0) > 0", []any(nil)),
+			Entry("starred=false", "starred", "false", "COALESCE(starred, 0) = 0", []any(nil)),
+			Entry("starred=True (case insensitive)", "starred", "True", "COALESCE(starred, 0) > 0", []any(nil)),
+			Entry("rating=true", "rating", "true", "COALESCE(rating, 0) > 0", []any(nil)),
 		)
 
 		It("returns nil if value is not a string", func() {

persistence/sql_base_repository.go

@@ -196,7 +196,7 @@ func (r *sqlRepository) withTableName(filter filterFunc) filterFunc {
 }
 
 // libraryIdFilter is a filter function to be added to resources that have a library_id column.
-func libraryIdFilter(_ string, value interface{}) Sqlizer {
+func libraryIdFilter(_ string, value any) Sqlizer {
 	return Eq{"library_id": value}
 }
 
@@ -281,7 +281,7 @@ func (r sqlRepository) toSQL(sq Sqlizer) (string, dbx.Params, error) {
 	return result, params, nil
 }
 
-func (r sqlRepository) queryOne(sq Sqlizer, response interface{}) error {
+func (r sqlRepository) queryOne(sq Sqlizer, response any) error {
 	query, args, err := r.toSQL(sq)
 	if err != nil {
 		return err
@@ -328,7 +328,7 @@ func queryWithStableResults[T any](r sqlRepository, sq SelectBuilder, options ..
 	}, nil
 }
 
-func (r sqlRepository) queryAll(sq SelectBuilder, response interface{}, options ...model.QueryOptions) error {
+func (r sqlRepository) queryAll(sq SelectBuilder, response any, options ...model.QueryOptions) error {
 	if len(options) > 0 && options[0].Offset > 0 {
 		sq = r.optimizePagination(sq, options[0])
 	}
@@ -347,7 +347,7 @@ func (r sqlRepository) queryAll(sq SelectBuilder, response interface{}, options
 }
 
 // queryAllSlice is a helper function to query a single column and return the result in a slice
-func (r sqlRepository) queryAllSlice(sq SelectBuilder, response interface{}) error {
+func (r sqlRepository) queryAllSlice(sq SelectBuilder, response any) error {
 	query, args, err := r.toSQL(sq)
 	if err != nil {
 		return err
@@ -394,7 +394,7 @@ func (r sqlRepository) count(countQuery SelectBuilder, options ...model.QueryOpt
 	return res.Count, err
 }
 
-func (r sqlRepository) putByMatch(filter Sqlizer, id string, m interface{}, colsToUpdate ...string) (string, error) {
+func (r sqlRepository) putByMatch(filter Sqlizer, id string, m any, colsToUpdate ...string) (string, error) {
 	if id != "" {
 		return r.put(id, m, colsToUpdate...)
 	}
@@ -408,14 +408,14 @@ func (r sqlRepository) putByMatch(filter Sqlizer, id string, m interface{}, cols
 	return r.put(res.ID, m, colsToUpdate...)
 }
 
-func (r sqlRepository) put(id string, m interface{}, colsToUpdate ...string) (newId string, err error) {
+func (r sqlRepository) put(id string, m any, colsToUpdate ...string) (newId string, err error) {
 	values, err := toSQLArgs(m)
 	if err != nil {
 		return "", fmt.Errorf("error preparing values to write to DB: %w", err)
 	}
 	// If there's an ID, try to update first
 	if id != "" {
-		updateValues := map[string]interface{}{}
+		updateValues := map[string]any{}
 
 		// This is a map of the columns that need to be updated, if specified
 		c2upd := slice.ToMap(colsToUpdate, func(s string) (string, struct{}) {

persistence/sql_bookmarks.go

@@ -37,7 +37,7 @@ func (r sqlRepository) bmkID(itemID ...string) And {
 func (r sqlRepository) bmkUpsert(itemID, comment string, position int64) error {
 	client, _ := request.ClientFrom(r.ctx)
 	user, _ := request.UserFrom(r.ctx)
-	values := map[string]interface{}{
+	values := map[string]any{
 		"comment":    comment,
 		"position":   position,
 		"updated_at": time.Now(),

persistence/sql_restful_test.go

@@ -30,7 +30,7 @@ var _ = Describe("sqlRestful", func() {
 			r.filterMappings = map[string]filterFunc{
 				"name": fullTextFilter("table"),
 			}
-			options.Filters = map[string]interface{}{"name": "'"}
+			options.Filters = map[string]any{"name": "'"}
 			Expect(r.parseRestFilters(context.Background(), options)).To(BeEmpty())
 		})
 
@@ -40,32 +40,32 @@ var _ = Describe("sqlRestful", func() {
 					return nil
 				},
 			}
-			options.Filters = map[string]interface{}{"name": "joe"}
+			options.Filters = map[string]any{"name": "joe"}
 			Expect(r.parseRestFilters(context.Background(), options)).To(BeEmpty())
 		})
 
 		It("returns a '=' condition for 'id' filter", func() {
-			options.Filters = map[string]interface{}{"id": "123"}
+			options.Filters = map[string]any{"id": "123"}
 			Expect(r.parseRestFilters(context.Background(), options)).To(Equal(squirrel.And{squirrel.Eq{"id": "123"}}))
 		})
 
 		It("returns a 'in' condition for multiples 'id' filters", func() {
-			options.Filters = map[string]interface{}{"id": []string{"123", "456"}}
+			options.Filters = map[string]any{"id": []string{"123", "456"}}
 			Expect(r.parseRestFilters(context.Background(), options)).To(Equal(squirrel.And{squirrel.Eq{"id": []string{"123", "456"}}}))
 		})
 
 		It("returns a 'like' condition for other filters", func() {
-			options.Filters = map[string]interface{}{"name": "joe"}
+			options.Filters = map[string]any{"name": "joe"}
 			Expect(r.parseRestFilters(context.Background(), options)).To(Equal(squirrel.And{squirrel.Like{"name": "joe%"}}))
 		})
 
 		It("uses the custom filter", func() {
 			r.filterMappings = map[string]filterFunc{
-				"test": func(field string, value interface{}) squirrel.Sqlizer {
+				"test": func(field string, value any) squirrel.Sqlizer {
 					return squirrel.Gt{field: value}
 				},
 			}
-			options.Filters = map[string]interface{}{"test": 100}
+			options.Filters = map[string]any{"test": 100}
 			Expect(r.parseRestFilters(context.Background(), options)).To(Equal(squirrel.And{squirrel.Gt{"test": 100}}))
 		})
 	})

persistence/sql_tags.go

@@ -60,7 +60,7 @@ func tagIDFilter(name string, idValue any) Sqlizer {
 }
 
 // tagLibraryIdFilter filters tags based on library access through the library_tag table
-func tagLibraryIdFilter(_ string, value interface{}) Sqlizer {
+func tagLibraryIdFilter(_ string, value any) Sqlizer {
 	return Eq{"library_tag.library_id": value}
 }
 
@@ -142,14 +142,14 @@ func (r *baseTagRepository) Count(options ...rest.QueryOptions) (int64, error) {
 	return r.count(sq, r.parseRestOptions(r.ctx, options...))
 }
 
-func (r *baseTagRepository) Read(id string) (interface{}, error) {
+func (r *baseTagRepository) Read(id string) (any, error) {
 	query := r.newSelect().Where(Eq{"id": id})
 	var res model.Tag
 	err := r.queryOne(query, &res)
 	return &res, err
 }
 
-func (r *baseTagRepository) ReadAll(options ...rest.QueryOptions) (interface{}, error) {
+func (r *baseTagRepository) ReadAll(options ...rest.QueryOptions) (any, error) {
 	query := r.newSelect(r.parseRestOptions(r.ctx, options...))
 	var res model.TagList
 	err := r.queryAll(query, &res)
@@ -160,7 +160,7 @@ func (r *baseTagRepository) EntityName() string {
 	return "tag"
 }
 
-func (r *baseTagRepository) NewInstance() interface{} {
+func (r *baseTagRepository) NewInstance() any {
 	return model.Tag{}
 }
 

persistence/tag_library_filtering_test.go

@@ -165,7 +165,7 @@ var _ = Describe("Tag Library Filtering", func() {
 
 			It("should respect explicit library_id filters within accessible libraries", func() {
 				tags := readAllTags(&regularUser, rest.QueryOptions{
-					Filters: map[string]interface{}{"library_id": libraryID2},
+					Filters: map[string]any{"library_id": libraryID2},
 				})
 				// Should see only tags from library 2: pop and rock(lib2)
 				Expect(tags).To(HaveLen(2))
@@ -174,7 +174,7 @@ var _ = Describe("Tag Library Filtering", func() {
 
 			It("should not return tags when filtering by inaccessible library", func() {
 				tags := readAllTags(&regularUser, rest.QueryOptions{
-					Filters: map[string]interface{}{"library_id": libraryID3},
+					Filters: map[string]any{"library_id": libraryID3},
 				})
 				// Should return no tags since user can't access library 3
 				Expect(tags).To(HaveLen(0))
@@ -182,7 +182,7 @@ var _ = Describe("Tag Library Filtering", func() {
 
 			It("should filter by library 1 correctly", func() {
 				tags := readAllTags(&regularUser, rest.QueryOptions{
-					Filters: map[string]interface{}{"library_id": libraryID1},
+					Filters: map[string]any{"library_id": libraryID1},
 				})
 				// Should see only rock from library 1
 				Expect(tags).To(HaveLen(1))
@@ -227,7 +227,7 @@ var _ = Describe("Tag Library Filtering", func() {
 
 			It("should allow headless processes to apply explicit library_id filters", func() {
 				tags := readAllTags(nil, rest.QueryOptions{
-					Filters: map[string]interface{}{"library_id": libraryID3},
+					Filters: map[string]any{"library_id": libraryID3},
 				})
 				// Should see only jazz from library 3
 				Expect(tags).To(HaveLen(1))
@@ -243,7 +243,7 @@ var _ = Describe("Tag Library Filtering", func() {
 
 			It("should respect explicit library_id filters", func() {
 				tags := readAllTags(&adminUser, rest.QueryOptions{
-					Filters: map[string]interface{}{"library_id": libraryID3},
+					Filters: map[string]any{"library_id": libraryID3},
 				})
 				// Should see only jazz from library 3
 				Expect(tags).To(HaveLen(1))
@@ -252,7 +252,7 @@ var _ = Describe("Tag Library Filtering", func() {
 
 			It("should filter by library 2 correctly", func() {
 				tags := readAllTags(&adminUser, rest.QueryOptions{
-					Filters: map[string]interface{}{"library_id": libraryID2},
+					Filters: map[string]any{"library_id": libraryID2},
 				})
 				// Should see pop and rock from library 2
 				Expect(tags).To(HaveLen(2))

persistence/tag_repository_test.go

@@ -234,7 +234,7 @@ var _ = Describe("TagRepository", func() {
 
 		It("should filter tags by partial value correctly", func() {
 			options := rest.QueryOptions{
-				Filters: map[string]interface{}{"name": "%rock%"}, // Tags containing 'rock'
+				Filters: map[string]any{"name": "%rock%"}, // Tags containing 'rock'
 			}
 			result, err := restRepo.ReadAll(options)
 			Expect(err).ToNot(HaveOccurred())
@@ -249,7 +249,7 @@ var _ = Describe("TagRepository", func() {
 
 		It("should filter tags by partial value using LIKE", func() {
 			options := rest.QueryOptions{
-				Filters: map[string]interface{}{"name": "%e%"}, // Tags containing 'e'
+				Filters: map[string]any{"name": "%e%"}, // Tags containing 'e'
 			}
 			result, err := restRepo.ReadAll(options)
 			Expect(err).ToNot(HaveOccurred())
@@ -264,7 +264,7 @@ var _ = Describe("TagRepository", func() {
 
 		It("should sort tags by value ascending", func() {
 			options := rest.QueryOptions{
-				Filters: map[string]interface{}{"name": "%r%"}, // Tags containing 'r'
+				Filters: map[string]any{"name": "%r%"}, // Tags containing 'r'
 				Sort:    "name",
 				Order:   "asc",
 			}
@@ -280,7 +280,7 @@ var _ = Describe("TagRepository", func() {
 
 		It("should sort tags by value descending", func() {
 			options := rest.QueryOptions{
-				Filters: map[string]interface{}{"name": "%r%"}, // Tags containing 'r'
+				Filters: map[string]any{"name": "%r%"}, // Tags containing 'r'
 				Sort:    "name",
 				Order:   "desc",
 			}

persistence/transcoding_repository.go

@@ -52,11 +52,11 @@ func (r *transcodingRepository) Count(options ...rest.QueryOptions) (int64, erro
 	return r.count(Select(), r.parseRestOptions(r.ctx, options...))
 }
 
-func (r *transcodingRepository) Read(id string) (interface{}, error) {
+func (r *transcodingRepository) Read(id string) (any, error) {
 	return r.Get(id)
 }
 
-func (r *transcodingRepository) ReadAll(options ...rest.QueryOptions) (interface{}, error) {
+func (r *transcodingRepository) ReadAll(options ...rest.QueryOptions) (any, error) {
 	sel := r.newSelect(r.parseRestOptions(r.ctx, options...)).Columns("*")
 	res := model.Transcodings{}
 	err := r.queryAll(sel, &res)
@@ -67,11 +67,11 @@ func (r *transcodingRepository) EntityName() string {
 	return "transcoding"
 }
 
-func (r *transcodingRepository) NewInstance() interface{} {
+func (r *transcodingRepository) NewInstance() any {
 	return &model.Transcoding{}
 }
 
-func (r *transcodingRepository) Save(entity interface{}) (string, error) {
+func (r *transcodingRepository) Save(entity any) (string, error) {
 	if !loggedUser(r.ctx).IsAdmin {
 		return "", rest.ErrPermissionDenied
 	}
@@ -83,7 +83,7 @@ func (r *transcodingRepository) Save(entity interface{}) (string, error) {
 	return id, err
 }
 
-func (r *transcodingRepository) Update(id string, entity interface{}, cols ...string) error {
+func (r *transcodingRepository) Update(id string, entity any, cols ...string) error {
 	if !loggedUser(r.ctx).IsAdmin {
 		return rest.ErrPermissionDenied
 	}

plugins/capabilities.go

@@ -1,5 +1,7 @@
 package plugins
 
+import "slices"
+
 // Capability represents a plugin capability type.
 // Capabilities are detected by checking which functions a plugin exports.
 type Capability string
@@ -25,11 +27,8 @@ func detectCapabilities(plugin functionExistsChecker) []Capability {
 	var capabilities []Capability
 
 	for cap, functions := range capabilityFunctions {
-		for _, fn := range functions {
-			if plugin.FunctionExists(fn) {
-				capabilities = append(capabilities, cap)
-				break // Found at least one function, plugin has this capability
-			}
+		if slices.ContainsFunc(functions, plugin.FunctionExists) {
+			capabilities = append(capabilities, cap) // Found at least one function, plugin has this capability
 		}
 	}
 
@@ -38,10 +37,5 @@ func detectCapabilities(plugin functionExistsChecker) []Capability {
 
 // hasCapability checks if the given capabilities slice contains a specific capability.
 func hasCapability(capabilities []Capability, cap Capability) bool {
-	for _, c := range capabilities {
-		if c == cap {
-			return true
-		}
-	}
-	return false
+	return slices.Contains(capabilities, cap)
 }

plugins/host_websocket.go

@@ -5,6 +5,7 @@ import (
 	"encoding/base64"
 	"errors"
 	"fmt"
+	"maps"
 	"net/http"
 	"net/url"
 	"strings"
@@ -200,9 +201,7 @@ func (s *webSocketServiceImpl) CloseConnection(ctx context.Context, connectionID
 func (s *webSocketServiceImpl) Close() error {
 	s.mu.Lock()
 	connections := make(map[string]*wsConnection, len(s.connections))
-	for k, v := range s.connections {
-		connections[k] = v
-	}
+	maps.Copy(connections, s.connections)
 	s.connections = make(map[string]*wsConnection)
 	s.mu.Unlock()
 

reflex.conf

@@ -1 +1 @@
--s -r "(\.go$$|\.cpp$$|\.h$$|navidrome.toml|resources|token_received.html)" -R "(^ui|^data|^db/migrations)" -- go run -race -tags netgo .
+-s -r "(\.go$$|\.cpp$$|\.h$$|navidrome.toml|resources|token_received.html)" -R "(^ui|^data|^db/migrations|_test\.go$$)" -- go run -race -tags netgo .

scanner/ignore_checker.go

@@ -65,8 +65,8 @@ func (ic *IgnoreChecker) PushAllParents(ctx context.Context, targetPath string)
 
 	// Load patterns for each parent directory
 	currentPath := "."
-	parts := strings.Split(path.Clean(targetPath), "/")
-	for _, part := range parts {
+	parts := strings.SplitSeq(path.Clean(targetPath), "/")
+	for part := range parts {
 		if part == "." || part == "" {
 			continue
 		}

scanner/metadata_old/metadata.go

@@ -215,8 +215,8 @@ func (t Tags) Lyrics() string {
 	}
 
 	for tag, value := range t.Tags {
-		if strings.HasPrefix(tag, "lyrics-") {
-			language := strings.TrimSpace(strings.TrimPrefix(tag, "lyrics-"))
+		if after, ok := strings.CutPrefix(tag, "lyrics-"); ok {
+			language := strings.TrimSpace(after)
 
 			if language == "" {
 				language = "xxx"