import {
  WebSocketGateway,
  WebSocketServer,
  OnGatewayConnection,
  OnGatewayDisconnect,
} from '@nestjs/websockets';
import { Server, Socket } from 'socket.io';
import { Logger } from '@nestjs/common';

@WebSocketGateway({
  cors: {
    origin: '*',
  },
  namespace: 'notifications',
})
export class NotificationGateway
  implements OnGatewayConnection, OnGatewayDisconnect
{
  @WebSocketServer()
  server!: Server; // ✅ FIX: เติม ! (Definite Assignment Assertion)

  private readonly logger = new Logger(NotificationGateway.name);

  handleConnection(client: Socket) {
    this.logger.log(`Client connected: ${client.id}`);
  }

  handleDisconnect(client: Socket) {
    this.logger.log(`Client disconnected: ${client.id}`);
  }

  /**
   * ส่งแจ้งเตือนไปหา User แบบ Real-time
   */
  sendToUser(userId: number, payload: any) {
    this.server.to(`user_${userId}`).emit('new_notification', payload);
  }
}