const WebSocket = require('ws')
const config = require('@config/index')
const DB = require('@libs/database')
const {
  msgSplit
} = require('./parser')
const event = require('@root/event')
// const _ = require('lodash')

class WS {
  constructor () {
    /** @type {WebSocket} */
    this.ws = null
    // cache struct
    // cache = {
    //   [channel]: {
    //     time: timestamp,
    //     list: []
    //   }
    // }
    this.cache = {}
    this.tick = null
    this.join = []
    this.tick = setInterval(this.runTick.bind(this), 1000)
    event.on('twitchJoin', (channel) => {
      this.joinChannel(channel)
    })
    event.on('twitchSend', data => {
      if (!('msg' in data) || typeof data.msg !== 'string') return
      if (!('channel' in data) || typeof data.channel !== 'string') return
      this.queueMsg(data.channel, data.msg)
    })
  }

  runBot () {
    if (!config.twitch.chat_host || !config.twitch.bot_oauth) return
    if (this.ws !== null) return
    this.ws = new WebSocket(`wss://${config.twitch.chat_host}:443`, 'irc')

    this.ws.on('open', this.handleOpen.bind(this))

    this.ws.on('message', this.handleMessage.bind(this))

    this.ws.on('error', this.handleError.bind(this))

    this.ws.on('close', this.handleExit.bind(this))
  }

  handleError (err) {
    console.log(err)
    this.ws = null
    this.runBot()
  }
  handleExit (code) {
    this.ws = null
    this.runBot()
  }
  handleMessage (data) {
    // socket message convert to string
    let d = data.toString()
    // split message with \n
    // filter array remove empty element
    // replace \r to empty
    let darr = d.split(/\n/).filter(t => t).map(t => t.replace(/\r$/, ''))

    for (let i in darr) {
      // parse message
      console.log('IRC::: > ', darr[i])
      msgSplit(this.ws, darr[i]).then(() => { /* pass */ })
    }
  }
  async handleOpen () {
    // from pool get db connection
    let db = await DB.connect()

    // login to twitch irc
    this.ws.send('PASS ' + config.twitch.bot_oauth)
    this.ws.send('NICK mtfosbot')
    this.ws.send('CAP REQ :twitch.tv/membership :twitch.tv/commands')

    // 取得要加入的頻道列表
    let text = `select "name" from "public"."twitch_channel" where "join" = true`
    let result = await db.query({
      text
    })

    // release pool connection
    await db.release()

    if (result !== null && result.rowCount > 0) {
      for (let row of result.rows) {
        if ('name' in row) {
          this.joinChannel(row.name)
          // this.ws.send('JOIN #' + row.name)
          // this.join.push(row.name)
        }
      }
    }
  }

  queueMsg (channel, msg) {
    if (typeof channel !== 'string' || channel.trim().length === 0) return
    if (typeof msg !== 'string' || msg.trim().length === 0) return
    if (channel in this.cache) {
      if ('list' in this.cache[channel]) {
        this.cache[channel].list = [...this.cache[channel].list, msg]
      } else {
        this.cache[channel].list = [msg]
      }
    } else {
      this.cache[channel] = {
        time: -1,
        list: [msg]
      }
    }
  }

  runTick () {
    if (this.cache === null || typeof this.cache !== 'object') return
    let time = Date.now()
    for (let i in this.cache) {
      if ('time' in this.cache[i] && this.cache[i].time <= (time - 1500)) {
        if ('list' in this.cache[i] && Array.isArray(this.cache[i].list) && this.cache[i].list.length > 0) {
          let msg = this.cache[i].list[0]
          this.cache[i].list = [...this.cache[i].list.slice(1)]
          this.sendMsg(i, msg)
        }
        this.cache[i].time = time
      } else {
        if ('list' in this.cache[i] && Array.isArray(this.cache[i].list) && this.cache[i].list.length > 0) {
          let msg = this.cache[i].list[0]
          this.cache[i].list = [...this.cache[i].list.slice(1)]
          this.sendMsg(i, msg)
        }
        this.cache[i].time = time
      }
    }
  }

  sendMsg (channel = null, message = null) {
    if (this.ws === null || !('send' in this.ws) || typeof this.ws.send !== 'function') return null
    if (channel === null || typeof channel !== 'string' || channel.trim().length === 0) return null
    if (message === null || typeof message !== 'string' || message.trim().length === 0) return null
    if (this.join.indexOf(channel) === -1) return null
    console.log(`IRC::: < ${`PRIVMSG #${channel} :${message}`}`)
    this.ws.send(`PRIVMSG #${channel} :${message}`)
  }

  joinChannel (channel = null) {
    if (this.ws === null || !('send' in this.ws) || typeof this.ws.send !== 'function') return null
    if (channel === null || typeof channel !== 'string' || channel.trim().length === 0) return null
    if (this.join.indexOf(channel) !== -1) return null
    console.log(`IRC::: < ${`JOIN #${channel.trim()}`}`)
    this.ws.send(`JOIN #${channel.trim()}`)
    this.join.push(channel.trim())
  }
}

module.exports = new WS()