# Data Architecture

## State Model

The single source of truth is `AppStateRest` (`src/app/state/rest.rs`):

```
AppStateRest
├── session: SessionRuntime (hive_mind state, convergence flag)
├── runtime: RuntimeState (mode, provider status)
├── chat: ChatState (messages, scroll)
├── input: InputState (text, cursor, autocomplete)
├── settings: Settings (provider, model, temperature, concise_output)
├── config: AppConfig (endpoints, credentials)
├── scroll: ScrollState (per-panel offset)
├── diff: DiffState (edit review)
├── tools: Vec with outputs
├── statusline, sidebar, etc.
└── toasts: pending notifications
```

**Mutation rules** (per CLAUDE.md):
- Mutated in-place from exactly two locations: `actions/mod.rs` (apply_action) and `controller/input.rs` (key handlers)
- Read-only from every other module
- No generic update function — direct field mutation only

## Persistence

### SQLite Message Log (`src/model/msglog/`)

| File | Purpose |
|------|---------|
| `schema.rs` | Table definitions (messages, sessions) |
| `mod.rs` | CRUD operations |
| `query.rs` | Query helpers (search, filter) |
| `blobs.rs` | Large message blob storage |
| `summary.rs` | Conversation summary cache |

Schema uses `rusqlite` (bundled) with per-session isolation — each session gets its own database.

### Memory System (`src/model/memory.rs`)

File-based memory stored under `~/.claude/projects/<project>/memory/`:

- Each memory is one markdown file with frontmatter (name, description, type)
- Types: `user`, `feedback`, `project`, `reference`
- Memory index in MEMORY.md
- Export/import for lesson sharing
- PID-file session lock prevents concurrent access

### Settings & Config (`src/model/`)

| File | Purpose |
|------|---------|
| `settings.rs` | Serialized user preferences (provider, model, theme) |
| `app_config.rs` | Provider endpoints, API key resolution from env |
| `session.rs` | Current session metadata |
| `conversation.rs` | In-memory conversation state |
| `editlog.rs` | Append-only JSONL edit audit trail |

### Edit Log

`src/model/editlog.rs` records every file mutation:

```json
{"ts": 123, "tool": "edit", "path": "src/main.rs",
 "reason": "fix bug", "content_sha256": "abc123",
 "bytes_delta": 15, "origin": "chat", "session_id": "sess-1"}
```

Max 5000 entries held in memory before pruning oldest.

## Context Management (`src/app/runtime/context/`)

| Module | Purpose |
|--------|---------|
| `tokens.rs` | Token counting via `tiktoken-rs` |
| `window.rs` | Token window resolution (fit within model context) |
| `dedup.rs` | Deduplication of repeated tool outputs |
| `squash.rs` | Compression of large JSON tool results |
| `shaping.rs` | Message dropping when context exceeds limits |

## IPC Data Flow

```
Daemon State ──diff──▶ serialize ──frame──▶ socket ──▶ Client
                                                          │
Client State ◀── apply_diff ◀── deserialize ◀──── socket ─┘
```