feat(chats): add per-user chat archive support

app/chats/repository.py

@@ -2,7 +2,7 @@ from sqlalchemy import Select, String, func, or_, select
 from sqlalchemy.orm import aliased
 from sqlalchemy.ext.asyncio import AsyncSession
 
-from app.chats.models import Chat, ChatMember, ChatMemberRole, ChatNotificationSetting, ChatType
+from app.chats.models import Chat, ChatMember, ChatMemberRole, ChatNotificationSetting, ChatType, ChatUserSetting
 from app.messages.models import Message, MessageHidden, MessageReceipt
 
 
@@ -53,7 +53,15 @@ async def count_chat_members(db: AsyncSession, *, chat_id: int) -> int:
 
 
 def _user_chats_query(user_id: int, query: str | None = None) -> Select[tuple[Chat]]:
-    stmt = select(Chat).join(ChatMember, ChatMember.chat_id == Chat.id).where(ChatMember.user_id == user_id)
+    stmt = (
+        select(Chat)
+        .join(ChatMember, ChatMember.chat_id == Chat.id)
+        .outerjoin(
+            ChatUserSetting,
+            (ChatUserSetting.chat_id == Chat.id) & (ChatUserSetting.user_id == user_id),
+        )
+        .where(ChatMember.user_id == user_id, func.coalesce(ChatUserSetting.archived, False).is_(False))
+    )
     if query and query.strip():
         q = f"%{query.strip()}%"
         stmt = stmt.where(
@@ -80,6 +88,30 @@ async def list_user_chats(
     return list(result.scalars().all())
 
 
+async def list_archived_user_chats(
+    db: AsyncSession,
+    *,
+    user_id: int,
+    limit: int = 50,
+    before_id: int | None = None,
+) -> list[Chat]:
+    stmt = (
+        select(Chat)
+        .join(ChatMember, ChatMember.chat_id == Chat.id)
+        .join(
+            ChatUserSetting,
+            (ChatUserSetting.chat_id == Chat.id) & (ChatUserSetting.user_id == user_id),
+        )
+        .where(ChatMember.user_id == user_id, ChatUserSetting.archived.is_(True))
+        .order_by(Chat.id.desc())
+        .limit(limit)
+    )
+    if before_id is not None:
+        stmt = stmt.where(Chat.id < before_id)
+    result = await db.execute(stmt)
+    return list(result.scalars().all())
+
+
 async def get_chat_by_id(db: AsyncSession, chat_id: int) -> Chat | None:
     result = await db.execute(select(Chat).where(Chat.id == chat_id))
     return result.scalar_one_or_none()
@@ -230,3 +262,28 @@ async def upsert_chat_notification_setting(
 async def is_chat_muted_for_user(db: AsyncSession, *, chat_id: int, user_id: int) -> bool:
     setting = await get_chat_notification_setting(db, chat_id=chat_id, user_id=user_id)
     return bool(setting and setting.muted)
+
+
+async def get_chat_user_setting(db: AsyncSession, *, chat_id: int, user_id: int) -> ChatUserSetting | None:
+    result = await db.execute(
+        select(ChatUserSetting).where(ChatUserSetting.chat_id == chat_id, ChatUserSetting.user_id == user_id)
+    )
+    return result.scalar_one_or_none()
+
+
+async def upsert_chat_archived_setting(
+    db: AsyncSession,
+    *,
+    chat_id: int,
+    user_id: int,
+    archived: bool,
+) -> ChatUserSetting:
+    setting = await get_chat_user_setting(db, chat_id=chat_id, user_id=user_id)
+    if setting:
+        setting.archived = archived
+        await db.flush()
+        return setting
+    setting = ChatUserSetting(chat_id=chat_id, user_id=user_id, archived=archived)
+    db.add(setting)
+    await db.flush()
+    return setting