fix(node): make node-list search case-insensitive for non-ASCII names (#6753)

core/data/src/commonMain/kotlin/org/meshtastic/core/data/datasource/NodeInfoReadDataSource.kt

@@ -28,7 +28,6 @@ interface NodeInfoReadDataSource {
 
     fun getNodesFlow(
         sort: String,
-        filter: String,
         includeUnknown: Boolean,
         hopsAwayMax: Int,
         lastHeardMin: Int,

core/data/src/commonMain/kotlin/org/meshtastic/core/data/datasource/SwitchingNodeInfoReadDataSource.kt

@@ -37,7 +37,6 @@ class SwitchingNodeInfoReadDataSource(private val dbManager: DatabaseProvider) :
 
     override fun getNodesFlow(
         sort: String,
-        filter: String,
         includeUnknown: Boolean,
         hopsAwayMax: Int,
         lastHeardMin: Int,
@@ -46,7 +45,6 @@ class SwitchingNodeInfoReadDataSource(private val dbManager: DatabaseProvider) :
             db.nodeInfoDao()
                 .getNodes(
                     sort = sort,
-                    filter = filter,
                     includeUnknown = includeUnknown,
                     hopsAwayMax = hopsAwayMax,
                     lastHeardMin = lastHeardMin,

core/data/src/commonMain/kotlin/org/meshtastic/core/data/repository/NodeRepositoryImpl.kt

@@ -49,6 +49,7 @@ import org.meshtastic.core.model.MyNodeInfo
 import org.meshtastic.core.model.Node
 import org.meshtastic.core.model.NodeAddress
 import org.meshtastic.core.model.NodeSortOption
+import org.meshtastic.core.model.matchesSearch
 import org.meshtastic.core.model.util.onlineTimeThreshold
 import org.meshtastic.core.repository.NodeRepository
 import org.meshtastic.proto.DeviceMetadata
@@ -191,12 +192,11 @@ class NodeRepositoryImpl(
     ): Flow<List<Node>> = nodeInfoReadDataSource
         .getNodesFlow(
             sort = sort.sqlValue,
-            filter = filter,
             includeUnknown = includeUnknown,
             hopsAwayMax = if (onlyDirect) 0 else -1,
             lastHeardMin = if (onlyOnline) onlineTimeThreshold() else -1,
         )
-        .mapLatest { list -> list.map { it.toModel() } }
+        .mapLatest { list -> list.map { it.toModel() }.filter { node -> node.matchesSearch(filter) } }
         .flowOn(dispatchers.io)
         .conflate()
 

core/database/src/commonMain/kotlin/org/meshtastic/core/database/dao/NodeInfoDao.kt

@@ -279,6 +279,8 @@ interface NodeInfoDao {
         NodeWithRelations,
         >
 
+    // Text search (name/id) is applied in Kotlin (NodeRepositoryImpl), not here: SQLite's LIKE/UPPER/LOWER only
+    // case-fold ASCII a-z/A-Z, so a WHERE-clause LIKE can't match e.g. "kolså" against "KOLSÅS" (#6750).
     @Query(
         """
     WITH OurNode AS (
@@ -288,11 +290,6 @@ interface NodeInfoDao {
     )
     SELECT * FROM nodes
     WHERE (:includeUnknown = 1 OR short_name IS NOT NULL)
-        AND (:filter = ''
-            OR (long_name LIKE '%' || :filter || '%'
-            OR short_name LIKE '%' || :filter || '%'
-            OR printf('!%08x', CASE WHEN num < 0 THEN num + 4294967296 ELSE num END) LIKE '%' || :filter || '%'
-            OR CAST(CASE WHEN num < 0 THEN num + 4294967296 ELSE num END AS TEXT) LIKE '%' || :filter || '%'))
         AND (:lastHeardMin = -1 OR last_heard >= :lastHeardMin)
         AND (:hopsAwayMax = -1 OR (hops_away <= :hopsAwayMax AND hops_away >= 0) OR num = (SELECT myNodeNum FROM my_node LIMIT 1))
     ORDER BY CASE
@@ -328,7 +325,6 @@ interface NodeInfoDao {
     @Transaction
     fun getNodes(
         sort: String,
-        filter: String,
         includeUnknown: Boolean,
         hopsAwayMax: Int,
         lastHeardMin: Int,

core/model/src/commonMain/kotlin/org/meshtastic/core/model/Node.kt

@@ -243,3 +243,21 @@ fun Config.DeviceConfig.Role?.isUnmessageableRole(): Boolean = this in
         Config.DeviceConfig.Role.TRACKER,
         Config.DeviceConfig.Role.TAK_TRACKER,
     )
+
+/** Offset converting a negative [Node.num] into its unsigned 32-bit decimal representation. */
+private const val UNSIGNED_INT_OFFSET = 4294967296L
+
+private val Node.unsignedNum: Long
+    get() = num.toLong().let { if (it < 0) it + UNSIGNED_INT_OFFSET else it }
+
+/**
+ * Matches node search text (long/short name, hex id, decimal id) with Unicode-aware case folding.
+ *
+ * Must run in Kotlin, not SQL: SQLite's LIKE/UPPER/LOWER only case-fold ASCII a-z/A-Z, so a query like "kolså" can
+ * never match a stored name of "KOLSÅS" via a SQL WHERE clause (#6750).
+ */
+fun Node.matchesSearch(filter: String): Boolean = filter.isBlank() ||
+    user.long_name.contains(filter, ignoreCase = true) ||
+    user.short_name.contains(filter, ignoreCase = true) ||
+    user.id.contains(filter, ignoreCase = true) ||
+    unsignedNum.toString().contains(filter, ignoreCase = true)

core/model/src/commonTest/kotlin/org/meshtastic/core/model/NodeTest.kt

@@ -137,6 +137,31 @@ class NodeTest {
         assertTrue(node.mismatchKey)
     }
 
+    @Test
+    fun matchesSearch_isCaseInsensitiveForNonAsciiLetters() {
+        val node = Node(num = 1, user = User(long_name = "KOLSÅS", short_name = "KOLS"))
+
+        // #6750: "kols" matched via ASCII-only SQL LIKE folding, but "kolså" did not.
+        assertTrue(node.matchesSearch("kols"))
+        assertTrue(node.matchesSearch("kolså"))
+        assertTrue(node.matchesSearch("KOLSÅS"))
+        assertFalse(node.matchesSearch("nomatch"))
+    }
+
+    @Test
+    fun matchesSearch_matchesHexAndDecimalNodeId() {
+        val node = Node(num = -1, user = User(id = "!ffffffff"))
+
+        assertTrue(node.matchesSearch("ffffffff"))
+        assertTrue(node.matchesSearch("4294967295"))
+        assertFalse(node.matchesSearch("1234"))
+    }
+
+    @Test
+    fun matchesSearch_blankFilterMatchesEveryNode() {
+        assertTrue(Node(num = 1).matchesSearch(""))
+    }
+
     private fun nodeWithPosition(num: Int, latitudeI: Int, longitudeI: Int): Node =
         Node(num = num, position = Position(latitude_i = latitudeI, longitude_i = longitudeI))
 }