add MSC3266 room summary API support

Signed-off-by: strawberry <strawberry@puppygock.gay>

src/api/client/unstable.rs

@@ -1,5 +1,8 @@
+use axum_client_ip::InsecureClientIp;
+use conduit::{warn, RumaResponse};
 use ruma::{
-	api::client::{error::ErrorKind, membership::mutual_rooms},
+	api::client::{error::ErrorKind, membership::mutual_rooms, room::get_summary},
+	events::room::member::MembershipState,
 	OwnedRoomId,
 };
 
@@ -12,8 +15,9 @@ use crate::{services, Error, Result, Ruma};
 /// TODO: Implement pagination, currently this just returns everything
 ///
 /// An implementation of [MSC2666](https://github.com/matrix-org/matrix-spec-proposals/pull/2666)
+#[tracing::instrument(skip_all, fields(%client), name = "mutual_rooms")]
 pub(crate) async fn get_mutual_rooms_route(
-	body: Ruma<mutual_rooms::unstable::Request>,
+	InsecureClientIp(client): InsecureClientIp, body: Ruma<mutual_rooms::unstable::Request>,
 ) -> Result<mutual_rooms::unstable::Response> {
 	let sender_user = body.sender_user.as_ref().expect("user is authenticated");
 
@@ -43,3 +47,116 @@ pub(crate) async fn get_mutual_rooms_route(
 		next_batch_token: None,
 	})
 }
+
+/// # `GET /_matrix/client/unstable/im.nheko.summary/rooms/{roomIdOrAlias}/summary`
+///
+/// Returns a short description of the state of a room.
+///
+/// This is the "wrong" endpoint that some implementations/clients may use
+/// according to the MSC. Request and response bodies are the same as
+/// `get_room_summary`.
+///
+/// An implementation of [MSC3266](https://github.com/matrix-org/matrix-spec-proposals/pull/3266)
+pub(crate) async fn get_room_summary_legacy(
+	InsecureClientIp(client): InsecureClientIp, body: Ruma<get_summary::msc3266::Request>,
+) -> Result<RumaResponse<get_summary::msc3266::Response>> {
+	get_room_summary(InsecureClientIp(client), body)
+		.await
+		.map(RumaResponse)
+}
+
+/// # `GET /_matrix/client/unstable/im.nheko.summary/summary/{roomIdOrAlias}`
+///
+/// Returns a short description of the state of a room.
+///
+/// TODO: support fetching remote room info if we don't know the room
+///
+/// An implementation of [MSC3266](https://github.com/matrix-org/matrix-spec-proposals/pull/3266)
+#[tracing::instrument(skip_all, fields(%client), name = "room_summary")]
+pub(crate) async fn get_room_summary(
+	InsecureClientIp(client): InsecureClientIp, body: Ruma<get_summary::msc3266::Request>,
+) -> Result<get_summary::msc3266::Response> {
+	let sender_user = body.sender_user.as_ref();
+
+	let room_id = services()
+		.rooms
+		.alias
+		.resolve(&body.room_id_or_alias)
+		.await?;
+
+	if !services().rooms.metadata.exists(&room_id)? {
+		return Err(Error::BadRequest(ErrorKind::NotFound, "Room is unknown to this server"));
+	}
+
+	if sender_user.is_none()
+		&& !services()
+			.rooms
+			.state_accessor
+			.is_world_readable(&room_id)
+			.unwrap_or(false)
+	{
+		return Err(Error::BadRequest(
+			ErrorKind::forbidden(),
+			"Room is not world readable, authentication is required",
+		));
+	}
+
+	Ok(get_summary::msc3266::Response {
+		room_id: room_id.clone(),
+		canonical_alias: services()
+			.rooms
+			.state_accessor
+			.get_canonical_alias(&room_id)?,
+		avatar_url: services()
+			.rooms
+			.state_accessor
+			.get_avatar(&room_id)?
+			.into_option()
+			.unwrap_or_default()
+			.url,
+		guest_can_join: services().rooms.state_accessor.guest_can_join(&room_id)?,
+		name: services()
+			.rooms
+			.state_accessor
+			.get_name(&room_id)
+			.unwrap_or(None),
+		num_joined_members: services()
+			.rooms
+			.state_cache
+			.room_joined_count(&room_id)
+			.unwrap_or_default()
+			.unwrap_or_else(|| {
+				warn!("Room {room_id} has no member count");
+				0
+			})
+			.try_into()
+			.expect("user count should not be that big"),
+		topic: services()
+			.rooms
+			.state_accessor
+			.get_room_topic(&room_id)
+			.unwrap_or(None),
+		world_readable: services()
+			.rooms
+			.state_accessor
+			.is_world_readable(&room_id)
+			.unwrap_or(false),
+		join_rule: services().rooms.state_accessor.get_join_rule(&room_id)?.0,
+		room_type: services().rooms.state_accessor.get_room_type(&room_id)?,
+		room_version: Some(services().rooms.state.get_room_version(&room_id)?),
+		membership: if let Some(sender_user) = sender_user {
+			services()
+				.rooms
+				.state_accessor
+				.get_member(&room_id, sender_user)?
+				.map_or_else(|| Some(MembershipState::Leave), |content| Some(content.membership))
+		} else {
+			None
+		},
+		encryption: services()
+			.rooms
+			.state_accessor
+			.get_room_encryption(&room_id)
+			.unwrap_or_else(|_e| None),
+	})
+}