如何通过使用ytdl- .mp3的Discord.js机器人发送下载的核心？

const Discord = require('discord.js');
const ytdl = require('ytdl-core');

const bot = new Discord.Client();

bot.on('ready', () => {
  console.log('Bot is ready');
});

bot.on('message', async (message) => {
  if (message.content.startsWith('!play')) {
    // 获取YouTube视频链接
    const url = message.content.split(' ')[1];
    
    // 检查链接是否有效
    if (!ytdl.validateURL(url)) {
      message.channel.send('无效的YouTube链接');
      return;
    }
    
    // 加入语音频道
    if (message.member.voice.channel) {
      const connection = await message.member.voice.channel.join();
      
      // 下载音频并发送给语音频道
      const stream = ytdl(url, { filter: 'audioonly' });
      connection.play(stream, { seek: 0, volume: 1 })
        .on('finish', () => {
          connection.disconnect();
        });
    } else {
      message.channel.send('请先加入一个语音频道');
    }
  }
});

bot.login('YOUR_BOT_TOKEN');