# ModeManagerService

Import it from `@grafloria/angular`.

Angular service wrapper for engine ModeManager. Provides reactive API using RxJS observables.

Features:
- Reactive mode state (BehaviorSubject)
- Mode transition guards
- Mode history tracking
- Mode-specific viewport settings
- Before/after hooks
- Mode analytics

```ts
@Injectable({ providedIn: 'root' })
export class ModeManagerService implements OnDestroy
```

**Properties**

| Name | Type | Default | Description |
| --- | --- | --- | --- |
| `mode$` |  |  | Observable of current diagram mode. Emits whenever mode changes. |
| `modeChanged$` |  |  | Observable of mode change events. Emits { previousMode, currentMode } on every mode change. |

**Methods**

- `ngOnDestroy(): void`
- `getMode(): DiagramMode` — Get current diagram mode.
- `setMode(mode: DiagramMode): void` — Set diagram mode. Mode change may be blocked by guards.
- `isDesignerMode(): boolean` — Check if in designer mode.
- `isRunningMode(): boolean` — Check if in running mode.
- `isViewMode(): boolean` — Check if in view mode.
- `isDebugMode(): boolean` — Check if in debug mode.
- `isPresentationMode(): boolean` — Check if in presentation mode.
- `isReadOnlyMode(): boolean` — Check if in read-only mode (any mode except designer).
- `addModeGuard(name: string, guard: ModeGuardFunction): void` — Add mode transition guard. Guards can prevent mode changes based on custom logic.
- `removeModeGuard(name: string): void` — Remove mode transition guard.
- `clearModeGuards(): void` — Clear all mode transition guards.
- `configureModeViewport(mode: DiagramMode, settings: ModeViewportSettings): void` — Configure viewport settings for specific mode.
- `getModeViewportSettings(mode: DiagramMode): ModeViewportSettings` — Get viewport settings for specific mode.
- `getModeHistory(): ModeHistoryEntry[]` — Get mode history. Returns array of mode entries with timestamps and durations.
- `clearModeHistory(): void` — Clear mode history (keeps current mode only).
- `previousMode(): void` — Navigate to previous mode in history.
- `nextMode(): void` — Navigate to next mode in history.
- `pushMode(mode: DiagramMode): void` — Push current mode onto stack and switch to new mode. Useful for temporary mode switches.
- `popMode(): void` — Pop mode from stack and return to previous mode.
- `getModeAnalytics(): ModeAnalytics` — Get mode analytics (time spent in each mode).
- `beforeModeChange(hook: ModeChangeHook): () => void` — Register before mode change hook. Hook can prevent mode change by returning false.
- `afterModeChange(hook: ModeChangeHook): () => void` — Register after mode change hook.

**Example**

```typescript
constructor(private modeManager: ModeManagerService) {}

ngOnInit() {
  // Subscribe to mode changes
  this.modeManager.mode$.subscribe(mode => {
    console.log('Current mode:', mode);
  });

  // Switch to running mode
  this.modeManager.setMode(DiagramMode.RUNNING);
}
```