import { IoAdapter } from '@nestjs/platform-socket.io';
import { INestApplicationContext, Logger } from '@nestjs/common';
import { ConfigService } from '@nestjs/config';
import { ServerOptions } from 'socket.io';
import { createAdapter } from '@socket.io/redis-adapter';
import Redis from 'ioredis';

export class RedisIoAdapter extends IoAdapter {
  private readonly logger = new Logger(RedisIoAdapter.name);
  private adapterConstructor: ReturnType<typeof createAdapter>;

  constructor(
    app: INestApplicationContext,
    private readonly configService: ConfigService,
  ) {
    super(app);
  }

  async connectToRedis(): Promise<void> {
    const host = this.configService.get<string>('redis.host', 'localhost');
    const port = this.configService.get<number>('redis.port', 6379);
    const password = this.configService.get<string>('redis.password') || undefined;
    const db = this.configService.get<number>('redis.db', 0);

    const pubClient = new Redis({ host, port, password, db });
    const subClient = new Redis({ host, port, password, db });

    await Promise.all([
      new Promise<void>((resolve) => pubClient.on('connect', resolve)),
      new Promise<void>((resolve) => subClient.on('connect', resolve)),
    ]);

    this.adapterConstructor = createAdapter(pubClient, subClient);
    this.logger.log(`Redis adapter connected to ${host}:${port}`);
  }

  createIOServer(port: number, options?: ServerOptions) {
    const server = super.createIOServer(port, options);
    server.adapter(this.adapterConstructor);
    return server;
  }
}