feat(multiplayer): support add/edit/remove playlist item

app/database/playlists.py

@@ -16,7 +16,10 @@ from sqlmodel import (
     ForeignKey,
     Relationship,
     SQLModel,
+    func,
+    select,
 )
+from sqlmodel.ext.asyncio.session import AsyncSession
 
 if TYPE_CHECKING:
     from .room import Room
@@ -59,9 +62,20 @@ class Playlist(PlaylistBase, table=True):
     room: "Room" = Relationship()
 
     @classmethod
-    async def from_hub(cls, playlist: PlaylistItem, room_id: int) -> "Playlist":
+    async def get_next_id_for_room(cls, room_id: int, session: AsyncSession) -> int:
+        stmt = select(func.coalesce(func.max(cls.id), -1) + 1).where(
+            cls.room_id == room_id
+        )
+        result = await session.exec(stmt)
+        return result.one()
+
+    @classmethod
+    async def from_hub(
+        cls, playlist: PlaylistItem, room_id: int, session: AsyncSession
+    ) -> "Playlist":
+        next_id = await cls.get_next_id_for_room(room_id, session=session)
         return cls(
-            id=playlist.id,
+            id=next_id,
             owner_id=playlist.owner_id,
             ruleset_id=playlist.ruleset_id,
             beatmap_id=playlist.beatmap_id,
@@ -74,6 +88,50 @@ class Playlist(PlaylistBase, table=True):
             room_id=room_id,
         )
 
+    @classmethod
+    async def update(cls, playlist: PlaylistItem, room_id: int, session: AsyncSession):
+        db_playlist = await session.exec(
+            select(cls).where(cls.id == playlist.id, cls.room_id == room_id)
+        )
+        db_playlist = db_playlist.first()
+        if db_playlist is None:
+            raise ValueError("Playlist item not found")
+        db_playlist.owner_id = playlist.owner_id
+        db_playlist.ruleset_id = playlist.ruleset_id
+        db_playlist.beatmap_id = playlist.beatmap_id
+        db_playlist.required_mods = [
+            msgpack_to_apimod(mod) for mod in playlist.required_mods
+        ]
+        db_playlist.allowed_mods = [
+            msgpack_to_apimod(mod) for mod in playlist.allowed_mods
+        ]
+        db_playlist.expired = playlist.expired
+        db_playlist.playlist_order = playlist.order
+        db_playlist.played_at = playlist.played_at
+        db_playlist.freestyle = playlist.freestyle
+        await session.commit()
+
+    @classmethod
+    async def add_to_db(
+        cls, playlist: PlaylistItem, room_id: int, session: AsyncSession
+    ):
+        db_playlist = await cls.from_hub(playlist, room_id, session)
+        session.add(db_playlist)
+        await session.commit()
+        await session.refresh(db_playlist)
+        playlist.id = db_playlist.id
+
+    @classmethod
+    async def delete_item(cls, item_id: int, room_id: int, session: AsyncSession):
+        db_playlist = await session.exec(
+            select(cls).where(cls.id == item_id, cls.room_id == room_id)
+        )
+        db_playlist = db_playlist.first()
+        if db_playlist is None:
+            raise ValueError("Playlist item not found")
+        await session.delete(db_playlist)
+        await session.commit()
+
 
 class PlaylistResp(PlaylistBase):
     beatmap: BeatmapResp | None = None