cinny/docs/handoff/features/lobby-forums/HANDOFF.md

Lobby & forums — handoff

Summary

Spaces in Paarrot can show a Lobby view: a card-based hierarchy of child rooms with drag-and-drop ordering, hero header, and category collapse. Forum spaces (m.forum room type or im.paarrot.room.kind = forum_space) use a post-feed style navigation instead of the standard lobby when opened.

User-facing behavior

• Opening a space lands on lobby (or forum feed for forum spaces)
• Lobby: hero, categories, room cards, DnD reorder (with permissions)
• Forum spaces: routed to post feed per getSpaceDefaultPath / shouldShowForumLobby
• Category open/closed state persisted per space

Architecture

Space route → Lobby.tsx (SpaceCardLobby)
  → LobbyHeader, LobbyHero, SpaceHierarchy
  → DnD reorder → m.space.child order updates
  → closedLobbyCategories atom (per-space category collapse)
  → shouldShowForumLobby(space) gates forum vs lobby behavior

Key files

Path	Role
cinny/src/app/features/lobby/Lobby.tsx	Main lobby view
cinny/src/app/features/lobby/LobbyHeader.tsx	Space header
cinny/src/app/features/lobby/LobbyHero.tsx	Hero banner area
cinny/src/app/features/lobby/SpaceHierarchy.tsx	Room tree/cards
cinny/src/app/features/lobby/DnD.tsx	Drag and drop
cinny/src/app/features/lobby/RoomItem.tsx	Room card
cinny/src/app/state/closedLobbyCategories.ts	Collapsed categories
cinny/src/app/state/hooks/closedLobbyCategories.ts	Jotai hook
cinny/src/app/pages/pathUtils.ts	getSpaceLobbyPath, forum routing
cinny/src/app/utils/room.ts	shouldShowForumLobby, getStateEvent
cinny/src/types/matrix/room.ts	RoomType.Forum, PaarrotRoomKind

Data model

Event / field	Purpose
m.space.child	Child room membership + order
im.paarrot.sub_rooms	Paarrot nested children (see sub-rooms handoff)
im.paarrot.room.kind	e.g. forum_space for forum behavior
m.room.create type	m.forum for forum rooms
Local: closedLobbyCategories	UI collapse state (not Matrix)

Dependencies

• Matrix space hierarchy events
• DnD library (see Lobby imports)
• Room power levels for reorder permission (useCanDropLobbyItem)

Integration points

• Sub-rooms: SpaceHierarchy merges im.paarrot.sub_rooms children
• Navigation: getSpaceDefaultPath chooses lobby vs forum path
• local-api: isSpaceLikeRoom treats forum kind as space-like for channel API

Testing

Manual

1. Open a normal space → lobby with child rooms.
2. Collapse/expand category; reload — state should persist.
3. Drag reorder child (as admin); verify m.space.child order.
4. Open forum-type space; verify feed navigation not lobby cards.
5. Test with sub-rooms under a child space card.

Automated

• None

Known issues & gotchas

• Forum detection spans two signals: m.forum create type and im.paarrot.room.kind
• DnD permission logic is custom per useCanDropLobbyItem — read before changing
• makeLobbyCategoryId(spaceId, childId) keys collapse state

Future work

• Unified hierarchy model (space.child + sub_rooms)
• Lobby theming from space avatar metadata

Related docs

• forum HANDOFF — post feed UI for forum spaces
• sub-rooms HANDOFF

Add your extra things here

• Route constant: SPACE_LOBBY_PATH in path utils
• SpaceCardLobby is the default export wrapper in Lobby.tsx