zustand

# LobeChat Zustand State Management

## Action Type Hierarchy

### 1. Public Actions
Main interfaces for UI components:
- Naming: Verb form (`createTopic`, `sendMessage`)
- Responsibilities: Parameter validation, flow orchestration

### 2. Internal Actions (`internal_*`)
Core business logic implementation:
- Naming: `internal_` prefix (`internal_createTopic`)
- Responsibilities: Optimistic updates, service calls, error handling
- Should not be called directly by UI

### 3. Dispatch Methods (`internal_dispatch*`)
State update handlers:
- Naming: `internal_dispatch` + entity (`internal_dispatchTopic`)
- Responsibilities: Calling reducers, updating store

## When to Use Reducer vs Simple `set`

**Use Reducer Pattern:**
- Managing object lists/maps (`messagesMap`, `topicMaps`)
- Optimistic updates
- Complex state transitions

**Use Simple `set`:**
- Toggling booleans
- Updating simple values
- Setting single state fields

## Optimistic Update Pattern

```typescript
internal_createTopic: async (params) => {
  const tmpId = Date.now().toString();

  // 1. Immediately update frontend (optimistic)
  get().internal_dispatchTopic(
    { type: 'addTopic', value: { ...params, id: tmpId } },
    'internal_createTopic'
  );

  // 2. Call backend service
  const topicId = await topicService.createTopic(params);

  // 3. Refresh for consistency
  await get().refreshTopic();
  return topicId;
},
```

**Delete operations**: Don't use optimistic updates (destructive, complex recovery)

## Naming Conventions

**Actions:**
- Public: `createTopic`, `sendMessage`
- Internal: `internal_createTopic`, `internal_updateMessageContent`
- Dispatch: `internal_dispatchTopic`
- Toggle: `internal_toggleMessageLoading`

**State:**
- ID arrays: `messageLoadingIds`, `topicEditingIds`
- Maps: `topicMaps`, `messagesMap`
- Active: `activeTopicId`
- Init flags: `topicsInit`

## Detailed Guides

- Action patterns: `references/action-patterns.md`
- Slice organization: `references/slice-organization.md`