import { wait } from './helper'
import { messageToString } from '../src/MessageHandler/messageToString'
import AbstractConnector from '../src/Connector.js'

var rooms = {}

export class TestRoom {
  constructor (roomname) {
    this.room = roomname
    this.users = new Map()
  }
  join (connector) {
    const userID = connector.y.userID
    this.users.set(userID, connector)
    for (let [uid, user] of this.users) {
      if (uid !== userID && (user.role === 'master' || connector.role === 'master')) {
        // The order is important because there is no timeout in send/receiveMessage
        // (the user that receives a sync step must already now about the sender)
        if (user.role === 'master') {
          connector.userJoined(uid, user.role)
          user.userJoined(userID, connector.role)
        } else if (connector.role === 'master') {
          user.userJoined(userID, connector.role)
          connector.userJoined(uid, user.role)
        }
      }
    }
  }
  leave (connector) {
    this.users.delete(connector.y.userID)
    this.users.forEach(user => {
      user.userLeft(connector.y.userID)
    })
  }
  send (sender, receiver, m) {
    var user = this.users.get(receiver)
    if (user != null) {
      user.receiveMessage(sender, m)
    }
  }
  broadcast (sender, m) {
    this.users.forEach((user, receiver) => {
      this.send(sender, receiver, m)
    })
  }
  async flushAll (users) {
    let flushing = true
    let allUsers = Array.from(this.users.values())
    if (users == null) {
      users = allUsers.map(user => user.y)
    }
    while (flushing) {
      await wait(10)
      let res = await Promise.all(allUsers.map(user => user._flushAll(users)))
      flushing = res.some(status => status === 'flushing')
    }
  }
}

function getTestRoom (roomname) {
  if (rooms[roomname] == null) {
    rooms[roomname] = new TestRoom(roomname)
  }
  return rooms[roomname]
}

export default class TestConnector extends AbstractConnector {
  constructor (y, options) {
    if (options === undefined) {
      throw new Error('Options must not be undefined!')
    }
    if (options.room == null) {
      throw new Error('You must define a room name!')
    }
    options.forwardAppliedOperations = options.role === 'master'
    super(y, options)
    this.options = options
    this.room = options.room
    this.chance = options.chance
    this.testRoom = getTestRoom(this.room)
    this.testRoom.join(this)
  }
  disconnect () {
    this.testRoom.leave(this)
    return super.disconnect()
  }
  logBufferParsed () {
    console.log(' === Logging buffer of user ' + this.y.userID + ' === ')
    for (let [user, conn] of this.connections) {
      console.log(` ${user}:`)
      for (let i = 0; i < conn.buffer.length; i++) {
        console.log(messageToString(conn.buffer[i]))
      }
    }
  }
  reconnect () {
    this.testRoom.join(this)
    super.reconnect()
    return new Promise(resolve => {
      this.whenSynced(resolve)
    })
  }
  send (uid, message) {
    super.send(uid, message)
    this.testRoom.send(this.y.userID, uid, message)
  }
  broadcast (message) {
    super.broadcast(message)
    this.testRoom.broadcast(this.y.userID, message)
  }
  async whenSynced (f) {
    var synced = false
    var periodicFlushTillSync = () => {
      if (synced) {
        f()
      } else {
        this.testRoom.flushAll([this.y]).then(function () {
          setTimeout(periodicFlushTillSync, 10)
        })
      }
    }
    periodicFlushTillSync()
    return super.whenSynced(function () {
      synced = true
    })
  }
  receiveMessage (sender, m) {
    if (this.y.userID !== sender && this.connections.has(sender)) {
      var buffer = this.connections.get(sender).buffer
      if (buffer == null) {
        buffer = this.connections.get(sender).buffer = []
      }
      buffer.push(m)
      if (this.chance.bool({likelihood: 30})) {
        // flush 1/2 with 30% chance
        var flushLength = Math.round(buffer.length / 2)
        buffer.splice(0, flushLength).forEach(m => {
          super.receiveMessage(sender, m)
        })
      }
    }
  }
  async _flushAll (flushUsers) {
    if (flushUsers.some(u => u.connector.y.userID === this.y.userID)) {
      // this one needs to sync with every other user
      flushUsers = Array.from(this.connections.keys()).map(uid => this.testRoom.users.get(uid).y)
    }
    for (let i = 0; i < flushUsers.length; i++) {
      let userID = flushUsers[i].connector.y.userID
      if (userID !== this.y.userID && this.connections.has(userID)) {
        let buffer = this.connections.get(userID).buffer
        if (buffer != null) {
          var messages = buffer.splice(0)
          for (let j = 0; j < messages.length; j++) {
            super.receiveMessage(userID, messages[j])
          }
        }
      }
    }
    return 'done'
  }
}
