const { literal, argument, string, DynamicCommandExceptionType } = require('brigadier-commands')
const { json } = require('../util/command/argument/json')
const TextMessage = require('../util/command/text_message')
const mc = require('minecraft-protocol')

const UNKNOWN_CLIENT_ERROR = new DynamicCommandExceptionType(string => new TextMessage(['Unknown client: ', string]))

module.exports = {
  clients: [],

  create () {
    return Object.create(this)
  },

  register (dispatcher) {
    const node = dispatcher.register(
      literal('client')
        .then(
          literal('create')
            .then(
              argument('options', json())
                .executes(c => this.createCommand(c))
            )
        )
        .then(
          literal('write')
            .then(
              argument('client', string())
                .then(
                  argument('name', string())
                    .then(
                      argument('data', json())
                        .executes(c => this.writeCommand(c))
                    )
                )
            )
        )
        .then(
          literal('end')
            .then(
              argument('client', string())
                .executes(c => this.endCommand(c))
            )
        )
        .then(
          literal('list')
            .executes(c => this.listCommand(c))
        )
    )

    node.description = 'Creates and manages this.clients using minecraft-protocol'
    node.permissionLevel = 0
  },

  cleanup () {
    this.clients.forEach(client => client.end())
  },

  createCommand (context) {
    const source = context.source
    const bot = source.bot

    const options = { host: bot.host, port: bot.port, ...context.getArgument('options') }

    const client = mc.createClient(options)
    const idx = this.clients.length

    client.once('login', () => source.sendFeedback([{ text: client.username, ...bot.styles.primary }, ' logged in']), false)

    client.on('end', () => {
      this.clients.splice(idx, 1)
      source.sendFeedback([{ text: client.username, ...bot.styles.primary }, ' ended'], false)
    })

    client.on('error', (err) => bot.tellraw({ text: err.toString(), ...bot.styles.error }, '@a'))

    this.clients.push(client)
  },

  writeCommand (context) {
    const idx = this.findClientIdxByString(context.getArgument('client'))

    const name = context.getArgument('name')
    const data = context.getArgument('data')

    this.clients[idx].write(name, data)
  },

  endCommand (context) {
    const source = context.source
    const idx = this.findClientIdxByString(context.getArgument('client'))

    this.clients[idx].end()
    this.clients.splice(idx, 1)
  },

  listCommand (context) {
    const source = context.source
    const bot = source.bot

    const list = []
    for (let i = 0; i < this.clients.length; i++) {
      const client = this.clients[i]
      if (i !== 0) list.push(', ')
      list.push(client.username)
    }

    source.sendFeedback([{ text: 'Clients: ', ...bot.styles.primary }, list], false)
  },

  findClientIdxByString (string) {
    let idx = Number(string)
    if (!this.clients[idx]) this.clients.forEach((client, cidx) => { if (client.username === string) idx = cidx })
    if (!this.clients[idx]) throw UNKNOWN_CLIENT_ERROR.create(string)

    return idx
  }
}