import 'virtual:windi.css'
import 'virtual:windi-devtools'

import IndexedDB from './database.js'
import MusicList from './music.js'
import ClientList from './client.js'
import Chat from './chat.js'

// 缓冲分片发送
const CHUNK_SIZE = 1024 * 64  // 默认每个块的大小为128KB
const THRESHOLD = 1024 * 1024 // 默认缓冲区的阈值为1MB
const DELAY = 50              // 默认延迟500ms

// 将两个ArrayBuffer合并成一个
function appendBuffer(buffer1, buffer2) {
  const tmp = new Uint8Array(buffer1.byteLength + buffer2.byteLength)
  tmp.set(new Uint8Array(buffer1), 0)
  tmp.set(new Uint8Array(buffer2), buffer1.byteLength)
  return tmp.buffer
}

//// 读取本地图像
//const imageStore = new IndexedDB('musicDatabase', 1, 'imageObjectStore')
//await imageStore.open()

// 读取本地音乐列表并标识为缓存状态(本地缓存)
const musicStore = new IndexedDB('musicDatabase', 1, 'musicObjectStore')
await musicStore.open()
const list = (await musicStore.getAll()).map(item => {
  return { save: true, ...item }
})

// 读取本地用户名(本地缓存)
const name = localStorage.getItem('username') ?? '游客'
const avatar = localStorage.getItem('avatar') ?? '/favicon.ico'


// 初始化客户端列表
const clientList = new ClientList({
  name,
  onexit: async client => {
    console.log(client.name, '离开频道', client)
    // 从列表中移除未缓存的此用户的音乐, 但可能多人都有此音乐且未缓存
    // 因此每条音乐都要检查是否有其他用户也有此音乐, 如果有则不移除
    const 此用户音乐 = client.musicList?.map(item => item.id) || []
    const 无数据音乐 = musicList.list.filter(item => !item.arrayBuffer).filter(item => {
      return 此用户音乐.includes(item.id)
    })
    无数据音乐.forEach(item => {
      const client = clientList.clientlist.find(client => {
        return client.musicList.find(x => x.id === item.id)
      })
      if (!client) musicList.remove(item)
    })

  }
})


// 初始化音乐列表(加入本地缓存)
const musicList = new MusicList({
  list,
  onplay: item => {
    console.log('播放音乐', item.name)
  },
  onstop: item => {
    console.log('停止音乐', item?.name)
  },
  onlike: (item, list) => {
    console.log('喜欢音乐', item.name)
    if (item.arrayBuffer) {
      musicStore.add(item)
      clientList.send('base', JSON.stringify({
        type: 'set_music_list',
        list: list.map(({ id, name, size, type }) => ({ id, name, size, type }))
      }))
    }
  },
  onunlike: (item, list) => {
    console.log('取消喜欢', item.name)
    if (item.arrayBuffer) {
      musicStore.delete(item.id)
      clientList.send('base', JSON.stringify({
        type: 'set_music_list',
        list: list.map(({ id, name, size, type }) => ({ id, name, size, type }))
      }))
    }
  },
  onban: item => {
    console.info('禁止音乐', item.name)
  },
  onunban: item => {
    console.info('解禁音乐', item.name)
  },
  onremove: item => {
    console.info('移除音乐', item.name)
    musicStore.delete(item.id)
  },
  onadd: (item, list) => {
    console.info('添加音乐', item.name)
  },
  onupdate: item => {
    console.info('更新音乐', item.name)
    musicStore.put(item)
  },
  onerror: error => {
    console.error('音乐列表错误', error)
  },
  onload: async item => {
    console.info('加载音乐', item)
    return await new Promise((resolve) => {
      var buffer = new ArrayBuffer(0) // 接收音乐数据
      var count = 0                   // 接收分片计数
      const chunkNumber = Math.ceil(item.size / 1024 / 64) // 64KB每片
      clientList.setChannel(`music-data-${item.id}`, {
        onmessage: async (event, client) => {
          console.log('收到音乐数据 chunk', `${count + 1}/${chunkNumber}`, buffer.byteLength)
          buffer = appendBuffer(buffer, event.data) // 合并分片准备存储
          item.arrayBufferChunks?.push(event.data)  // 保存分片给边下边播
          count++
          if (buffer.byteLength >= item.size) {
            console.log('音乐数据接收完毕')
            item.arrayBuffer = buffer
            event.target.close() // 关闭信道
            resolve(item)
          }
        }
      })
      const client = clientList.clientlist.find(client => {
        return client.musicList.find(x => x.id === item.id)
      })
      console.info('向', client.name, '请求音乐数据')

      const c = Math.ceil(item.size / CHUNK_SIZE)
      console.log('需要接收', c, '个分片')

      clientList.sendto(client.id, 'base', JSON.stringify({
        type: 'get_music_data', id: item.id, channel: `music-data-${item.id}`
      }))
    })
  }
})

const chat = new Chat({
  onsend: async (text, list) => {
    console.log('发送消息', text)
    clientList.send('chat', JSON.stringify({ type: 'message', text }))
    chat.add({ name, text, time: new Date().toLocaleTimeString() })
    console.log('发送结束')
  },
  onexit: async () => {
    console.log('退出聊天室')
  }
})

// 与每个客户端都建立聊天信道
clientList.setChannel('chat', {
  onopen: async event => {
    console.debug('打开信道', event.target.label)
  },
  onmessage: async (event, client) => {
    const data = JSON.parse(event.data)
    if (data.type === 'message') {
      console.log(client.name, '发来消息:', data)
      chat.add({ name: client.name, text: data.text, time: new Date().toLocaleTimeString() })
      return
    }
    if (data.type === 'image') {
      console.log(client.name, '发来图片:', data)
      return
    }
    console.log('未知类型:', data.type)
  },
  onclose: event => {
    console.log('关闭信道', event.target.label)
  },
  onerror: event => {
    console.error('信道错误', event.target.label, event.error)
  }
})

// 与每个客户端都建立基本信道, 用于交换和调度信息
clientList.setChannel('base', {
  onopen: async event => {
    console.debug('打开信道', event.target.label, '广播请求音乐列表和身份信息')
    clientList.send('base', JSON.stringify({ type: 'get_music_list' }))   // 要求对方发送音乐列表
    clientList.send('base', JSON.stringify({ type: 'get_user_profile' })) // 要求对方发送身份信息
  },
  onmessage: async (event, client) => {
    const data = JSON.parse(event.data)
    if (data.type === 'get_user_profile') {
      console.log(client.name, '请求身份信息:', data)
      // 包过大会导致发送失败, 因此需要分开发送
      clientList.sendto(client.id, 'base', JSON.stringify({
        type: 'set_user_profile',
        name: name,
        avatar: avatar,
      }))
      return
    }
    if (data.type === 'set_user_profile') {
      console.log(client.name, '发来身份信息:', data)
      console.log('将身份信息保存到本机记录:', client)
      client.name = data.name
      client.avatar = data.avatar
      // 还需要更新组件的用户信息
      console.log('更新组件的用户信息:', data, client)
      clientList.setAvatar({ id: client.id, ...data })
      return
    }
    if (data.type === 'get_image_list') {
      // webrtc://用户@域名:端口/信道标识/资源ID
    }
    if (data.type === 'get_music_list') {
      const ms = musicList.list.filter(item => item.arrayBuffer)
      console.log(client.name, '请求音乐列表:', ms)
      clientList.sendto(client.id, 'base', JSON.stringify({
        type: 'set_music_list',
        list: ms.map(({ id, name, size, type }) => ({ id, name, size, type }))
      }))
      return
    }
    if (data.type === 'set_music_list') {
      console.log(client.name, '发来音乐列表:', `x${JSON.parse(event.data).list.length}`)
      client.musicList = data.list
      client.musicList.forEach(music => musicList.add(music))
      return
    }
    if (data.type === 'get_music_data') {
      // 建立一个信道, 用于传输音乐数据(接收方已经准备好摘要信息)
      console.log(client.name, '建立一个信道, 用于传输音乐数据', musicList.list)
      musicList.list.filter(item => item.id === data.id).forEach(item => {
        const ch = client.webrtc.createDataChannel(data.channel, { reliable: true })
        ch.onopen = async event => {
          console.log(client.name, `打开 ${data.channel} 信道传输音乐数据`, item.name)
          // 将音乐数据分成多个小块，并逐个发送
          async function sendChunk(dataChannel, data, index = 0, buffer = new ArrayBuffer(0)) {
            while (index < data.byteLength) {
              if (dataChannel.bufferedAmount <= THRESHOLD) {
                const chunk = data.slice(index, index + CHUNK_SIZE)
                dataChannel.send(chunk)
                index += CHUNK_SIZE
                buffer = appendBuffer(buffer, chunk)
              }
              await new Promise((resolve) => setTimeout(resolve, DELAY))
            }
            return buffer
          }
          await sendChunk(ch, item.arrayBuffer)
          console.log(client.name, `获取 ${data.channel} 信道数据结束`, item.name)
          ch.close() // 关闭信道
        }
      })
      return
    }
    console.log('未知类型:', data.type)
  },
  onclose: event => {
    console.log('关闭信道', event.target.label)
  },
  onerror: event => {
    console.error('信道错误', event.target.label, event.error)
  }
})

// 延迟1500ms
//await new Promise((resolve) => setTimeout(resolve, 100))

// 设置自己的主机名
const nameInput = document.createElement('input')
nameInput.type = 'text'
nameInput.placeholder = '请设置你的昵称'
nameInput.value = name
nameInput.onchange = event => {
  localStorage.setItem('username', event.target.value)
  window.location.reload() // 简单刷新页面
}
document.body.appendChild(nameInput)

// 设置标签为自己的头像
if (localStorage.getItem('avatar')) {
  const favicon = document.createElement('link')
  favicon.rel = 'icon'
  favicon.href = localStorage.getItem('avatar')
  document.head.appendChild(favicon)
}
// 设置标题为自己的昵称
if (localStorage.getItem('username')) {
  document.title = localStorage.getItem('username')
}