# Architecture

## Quick Start

```bash
npm start         # dev server on :8080
npm run build     # production build → dist/
npm run lint      # eslint + prettier
npm run typecheck # tsc --noEmit
```

Build: **Vite 5.4** with vanilla-extract, WASM, PWA plugins.

## Source Layout

```
src/
├── index.tsx                    # Entry point
├── client/
│   ├── initMatrix.ts            # Matrix SDK init (createClient, startClient, logout)
│   └── secretStorageKeys.js     # Crypto callbacks
├── types/matrix/                # Matrix protocol types (room.ts, accountData.ts, common.ts)
└── app/
    ├── i18n.ts                  # i18next config
    ├── pages/
    │   └── App.tsx              # Root component (providers, config loader)
    ├── features/                # Feature modules
    ├── components/              # Shared components
    ├── hooks/                   # ~117 custom hooks
    ├── state/                   # Jotai atoms
    ├── plugins/                 # Content plugins
    ├── utils/                   # Utilities
    └── styles/                  # Vanilla-extract global styles
```

## Pages & Routing (`src/app/pages/`)

Router in `Router.tsx` — `createBrowserRouter` / `createHashRouter`.

- **Auth**: `auth/login/`, `auth/register/`, `auth/reset-password/`
- **Client**: `client/` — main layout after login
  - `home/` — Home timeline (path: `/home/`, root `/` redirects here)
  - `direct/` — DMs (path: `/direct/`)
  - `space/` — Space view (path: `/:spaceIdOrAlias/`)
  - `explore/` — Public rooms (path: `/explore/`)
  - `inbox/` — Notifications, invites (path: `/inbox/`)
  - `create/` — New room/space (path: `/create/`)
  - `sidebar/` — Tab components for sidebar nav
  - `WelcomePage.tsx` — Empty state
  - `SyncStatus.tsx`, `SpecVersions.tsx` — Connection status

## Features (`src/app/features/`)

| Dir | Purpose |
|-----|---------|
| `room/` | Core room view — **RoomTimeline.tsx** (~63KB), **RoomInput.tsx** (~24KB), **RoomViewHeader.tsx** (~18KB), MembersDrawer, MessageEditor, RoomTombstone |
| `room-nav/` | Room list navigation items & categories |
| `room-settings/` | Room-specific settings page |
| `common-settings/` | Shared settings: general, members, permissions, emojis-stickers, developer-tools |
| `space-settings/` | Space-specific settings |
| `settings/` | User settings (general, account, notifications, devices, emojis, about, dev-tools) |
| `lobby/` | Space/room lobby view |
| `search/` | Global search |
| `message-search/` | In-room message search |
| `create-chat/` | DM creation flow |
| `create-room/` | Room creation |
| `create-space/` | Space creation |
| `add-existing/` | Join existing rooms |
| `join-before-navigate/` | Pre-join navigation logic |
| `call/` | Element Call integration |
| `call-status/` | Call state display |

## Key Components (`src/app/components/`)

- `message/` — Message rendering (layout variants: compact, bubble, modern)
- `editor/` — Slate-based rich text editor
- `emoji-board/` — Emoji picker
- `image-pack-view/` — Custom emoji pack management
- `image-viewer/`, `Pdf-viewer/` — Media viewers
- `sidebar/` — Sidebar navigation
- `user-profile/` — User info, power chips, moderation
- `member-tile/` — Member list items
- `power/` — Power level UI
- `upload-card/` — Upload progress cards
- `url-preview/` — Link previews
- `page/` — Page layout wrapper (Page, PageHeader, PageContent)
- `setting-tile/` — Settings list item pattern
- `sequence-card/`, `cutout-card/` — Card layouts
- `uia-stages/` — User-interactive auth stages (email, captcha, token)
- `room-intro/` — Room introduction card
- `invite-user-prompt/`, `join-address-prompt/`, `leave-room-prompt/` — Dialogs

## State Management

**Jotai** atoms in `src/app/state/`:

- `settings.ts` — User preferences (MessageLayout, DateFormat, …)
- `sessions.ts` — Active session
- `upload.ts` — Upload progress
- `room/` — `roomInputDrafts`, `roomToParents`, `roomToUnread`
- `room-list/` — `roomList`, `inviteList`, sorting/filtering

Some atoms persist to localStorage (e.g. `settings.ts`, `navToActivePath.ts`), others are in-memory only (e.g. `upload.ts`, `roomInputDrafts.ts`). Access via hooks in `state/hooks/`.

## Matrix SDK Patterns

```tsx
const mx = useMatrixClient();                               // Get SDK instance
const room = useRoom();                                     // Current room
const stateEvent = useStateEvent(room, StateEvent.Type);    // Room state
const powerLevels = usePowerLevels(room);                   // Permissions
```

## Key Libraries

- **React 18.2** + React Router DOM 6
- **matrix-js-sdk 38.2** — Matrix protocol
- **folds 2.6** — UI component library
- **jotai 2.6** — State management
- **vanilla-extract** — Type-safe CSS
- **slate 0.123** — Rich text editor
- **@tanstack/react-query 5** — Data fetching
- **@tanstack/react-virtual 3** — Virtual scrolling
- **i18next 23 + react-i18next 15** — Localisation
- **Capacitor 8.3** — Native Android wrapper
- **@capacitor/browser 8.0** — External link handling in native

## Git

- Main branch: `dev`
- Current work branch: `vojo/dev`
- Semantic-release on `dev` branch
- CI: GitHub Actions (build, deploy, docker, netlify)