# State Management

### LocalStorage

The application uses browser `localStorage` for state persistence:

**Stored Data:**
- `jwt` - JWT authentication token
- `agentID` - Current user/agent ID
- `role` - User roles (JSON array)
- `username` - Username
- Other session-specific data

### Observable Pattern (RxJS)

Services use RxJS Observables for reactive data flow:
```typescript
// Example from ApiService
return this.http.post<any>(OSAS_API + '/auth/signin', payload, { headers });
```

Components subscribe to Observables:
```typescript
this.apiService.getUser(username, password).subscribe(
  response => { /* handle response */ },
  error => { /* handle error */ }
);
```

### Service State

Services maintain application state:
- Singleton services (providedIn: 'root')
- State shared across components
- Data caching where appropriate