From 16dcfb2e84aa9bca9499a8aa6c48b33672c29353 Mon Sep 17 00:00:00 2001
From: Stefan Ceriu <stefanc@matrix.org>
Date: Sun, 25 Feb 2024 15:39:40 +0200
Subject: [PATCH] feat: Expose a room list filter for Invites only

---
 bindings/matrix-sdk-ffi/src/room_list.rs      |  7 +-
 .../src/room_list_service/filters/invite.rs   | 84 +++++++++++++++++++
 .../src/room_list_service/filters/mod.rs      |  2 +
 3 files changed, 91 insertions(+), 2 deletions(-)
 create mode 100644 crates/matrix-sdk-ui/src/room_list_service/filters/invite.rs

diff --git a/bindings/matrix-sdk-ffi/src/room_list.rs b/bindings/matrix-sdk-ffi/src/room_list.rs
index 511c259d3..8437df88b 100644
--- a/bindings/matrix-sdk-ffi/src/room_list.rs
+++ b/bindings/matrix-sdk-ffi/src/room_list.rs
@@ -16,8 +16,9 @@ use matrix_sdk_ui::{
     room_list_service::{
         filters::{
             new_filter_all, new_filter_any, new_filter_category, new_filter_favourite,
-            new_filter_fuzzy_match_room_name, new_filter_non_left, new_filter_none,
-            new_filter_normalized_match_room_name, new_filter_unread, RoomCategory,
+            new_filter_fuzzy_match_room_name, new_filter_invite, new_filter_non_left,
+            new_filter_none, new_filter_normalized_match_room_name, new_filter_unread,
+            RoomCategory,
         },
         BoxedFilterFn,
     },
@@ -421,6 +422,7 @@ pub enum RoomListEntriesDynamicFilterKind {
     NonLeft,
     Unread,
     Favourite,
+    Invite,
     Category { expect: RoomListFilterCategory },
     None,
     NormalizedMatchRoomName { pattern: String },
@@ -460,6 +462,7 @@ impl FilterWrapper {
             Kind::NonLeft => Self(Box::new(new_filter_non_left(client))),
             Kind::Unread => Self(Box::new(new_filter_unread(client))),
             Kind::Favourite => Self(Box::new(new_filter_favourite(client))),
+            Kind::Invite => Self(Box::new(new_filter_invite(client))),
             Kind::Category { expect } => Self(Box::new(new_filter_category(client, expect.into()))),
             Kind::None => Self(Box::new(new_filter_none())),
             Kind::NormalizedMatchRoomName { pattern } => {
diff --git a/crates/matrix-sdk-ui/src/room_list_service/filters/invite.rs b/crates/matrix-sdk-ui/src/room_list_service/filters/invite.rs
new file mode 100644
index 000000000..146b41d8f
--- /dev/null
+++ b/crates/matrix-sdk-ui/src/room_list_service/filters/invite.rs
@@ -0,0 +1,84 @@
+use matrix_sdk::{Client, RoomListEntry};
+use matrix_sdk_base::RoomState;
+
+use super::Filter;
+
+struct InviteRoomMatcher<F>
+where
+    F: Fn(&RoomListEntry) -> Option<bool>,
+{
+    is_invite: F,
+}
+
+impl<F> InviteRoomMatcher<F>
+where
+    F: Fn(&RoomListEntry) -> Option<bool>,
+{
+    fn matches(&self, room_list_entry: &RoomListEntry) -> bool {
+        if !matches!(room_list_entry, RoomListEntry::Filled(_) | RoomListEntry::Invalidated(_)) {
+            return false;
+        }
+
+        (self.is_invite)(room_list_entry).unwrap_or(false)
+    }
+}
+
+/// Create a new filter that will accept all filled or invalidated entries, but
+/// filters out rooms that are not invites (see
+/// [`matrix_sdk_base::RoomState::Invited`]).
+pub fn new_filter(client: &Client) -> impl Filter {
+    let client = client.clone();
+
+    let matcher = InviteRoomMatcher {
+        is_invite: move |room| match room {
+            RoomListEntry::Filled(room_id) | RoomListEntry::Invalidated(room_id) => {
+                let room = client.get_room(room_id)?;
+                Some(room.state() == RoomState::Invited)
+            }
+            _ => None,
+        },
+    };
+
+    move |room_list_entry| -> bool { matcher.matches(room_list_entry) }
+}
+
+#[cfg(test)]
+mod tests {
+    use std::ops::Not;
+
+    use matrix_sdk::RoomListEntry;
+    use ruma::room_id;
+
+    use super::InviteRoomMatcher;
+
+    #[test]
+    fn test_is_invite() {
+        let matcher = InviteRoomMatcher { is_invite: |_| Some(true) };
+
+        assert!(matcher.matches(&RoomListEntry::Empty).not());
+        assert!(matcher.matches(&RoomListEntry::Filled(room_id!("!r0:bar.org").to_owned())));
+        assert!(matcher.matches(&RoomListEntry::Invalidated(room_id!("!r0:bar.org").to_owned())));
+    }
+
+    #[test]
+    fn test_is_not_invite() {
+        let matcher = InviteRoomMatcher { is_invite: |_| Some(false) };
+
+        assert!(matcher.matches(&RoomListEntry::Empty).not());
+        assert!(matcher.matches(&RoomListEntry::Filled(room_id!("!r0:bar.org").to_owned())).not());
+        assert!(matcher
+            .matches(&RoomListEntry::Invalidated(room_id!("!r0:bar.org").to_owned()))
+            .not());
+    }
+
+    #[test]
+    fn test_invite_state_cannot_be_found() {
+        let matcher = InviteRoomMatcher { is_invite: |_| None };
+
+        assert!(matcher.matches(&RoomListEntry::Empty).not());
+        assert!(matcher.matches(&RoomListEntry::Filled(room_id!("!r0:bar.org").to_owned())).not());
+        assert!(matcher
+            .matches(&RoomListEntry::Invalidated(room_id!("!r0:bar.org").to_owned()))
+            .not());
+    }
+}
diff --git a/crates/matrix-sdk-ui/src/room_list_service/filters/mod.rs b/crates/matrix-sdk-ui/src/room_list_service/filters/mod.rs
index 012b5f32f..fdc667934 100644
--- a/crates/matrix-sdk-ui/src/room_list_service/filters/mod.rs
+++ b/crates/matrix-sdk-ui/src/room_list_service/filters/mod.rs
@@ -59,6 +59,7 @@ mod any;
 mod category;
 mod favourite;
 mod fuzzy_match_room_name;
+mod invite;
 mod non_left;
 mod none;
 mod normalized_match_room_name;
@@ -70,6 +71,7 @@ pub use any::new_filter as new_filter_any;
 pub use category::{new_filter as new_filter_category, RoomCategory};
 pub use favourite::new_filter as new_filter_favourite;
 pub use fuzzy_match_room_name::new_filter as new_filter_fuzzy_match_room_name;
+pub use invite::new_filter as new_filter_invite;
 use matrix_sdk::RoomListEntry;
 pub use non_left::new_filter as new_filter_non_left;
 pub use none::new_filter as new_filter_none;