export interface PostMessageEvent {
  type: string;
  payload?: any;
}

export class PostMessageAPI {
  private targetOrigin: string;

  constructor(targetOrigin: string = '*') {
    this.targetOrigin = targetOrigin;
  }

  // Send events to parent window
  send(type: string, payload?: any): void {
    if (typeof window !== 'undefined' && window.parent) {
      window.parent.postMessage(
        {
          type,
          payload,
          source: 'virtual-banker-widget',
        },
        this.targetOrigin
      );
    }
  }

  // Listen for messages from parent window
  on(type: string, callback: (payload?: any) => void): () => void {
    const handler = (event: MessageEvent) => {
      if (event.data && event.data.type === type && event.data.source === 'virtual-banker-host') {
        callback(event.data.payload);
      }
    };

    window.addEventListener('message', handler);

    // Return unsubscribe function
    return () => {
      window.removeEventListener('message', handler);
    };
  }

  // Widget events
  ready(): void {
    this.send('ready');
  }

  sessionStarted(sessionId: string): void {
    this.send('session_started', { sessionId });
  }

  actionRequested(action: string, params: any): void {
    this.send('action_requested', { action, params });
  }

  actionCompleted(action: string, result: any): void {
    this.send('action_completed', { action, result });
  }

  handoffToHuman(reason: string): void {
    this.send('handoff_to_human', { reason });
  }
}