channel.js

const Modes = require('./modes');
const Message = require('./message');
const { debuglog } = require('util');

const debug = debuglog('ircs:Channel');

/**
 * Represents an IRC Channel on the server.
 */
class Channel {
  /**
   * Create a new channel.
   *
   * @param {string} name Channel name. (Starting with # or &, preferably.)
   */
  constructor(name) {
    this.name = name
    this.users = []
    this.topic = null

    this.modes = new Modes(this)
  }

  static isValidChannelName(name) {
    // https://tools.ietf.org/html/rfc1459#section-1.3
    return name.length <= 200 &&
      (name[0] === '#' || name[0] === '&') &&
      name.indexOf(' ') === -1 &&
      name.indexOf(',') === -1 &&
      name.indexOf('\x07') === -1 // ^G
  }

  /**
   * Joins a user into this channel.
   *
   * @param {User} user Joining user.
   */
  join(user) {
    if (this.hasUser(user)) {
      console.log(thsi.toString());
      throw new Error(`User ${user.nickname} has already join this channel ${this.name}`);
    } else {
      user.join(this);
      this.users.push(user);
    }
    if (this.users.length === 1) {
      this.addOp(user);
    }
    return this;
  }

  /**
   * Parts a user from this channel.
   *
   * @param {User} user Parting user.
   */
  part(user) {
    let i = this.users.indexOf(user)
    if (i !== -1) {
      this.users.splice(i, 1)
    }
    i = user.channels.indexOf(this)
    if (i !== -1) {
      user.channels.splice(i, 1)
    }
  }

  /**
   * Checks if a user is in this channel.
   *
   * @param {User} user User to look for.
   *
   * @return boolean Whether the user is here.
   */
  hasUser(user) {
    return this.users.indexOf(user) !== -1
  }

  /**
   * Sends a message to all users in a channel, including the sender.
   *
   * @param {Message} message Message to send.
   */
  send(message) {
    if (!(message instanceof Message)) {
      message = new Message(...arguments);
    }
    debug(this.name, 'send', message.toString());
    this.users.forEach(user => user.send(message));
  }

  /**
   * Broadcasts a message to all users in a channel, except the sender.
   *
   * @param {Message} message Message to send.
   */
  broadcast(message) {
    if (!(message instanceof Message)) {
      message = new Message(...arguments)
    }
    this.users.forEach((u) => {
      if (!u.matchesMask(message.prefix)) u.send(message)
    })
  }

  addOp(user) {
    if (!this.hasOp(user)) {
      this.modes.add('o', user.nickname)
    }
  }

  removeOp(user) {
    this.modes.remove('o', user.nickname)
  }

  hasOp(user) {
    return this.modes.has('o', user.nickname)
  }

  addVoice(user) {
    if (!this.hasVoice(user)) {
      this.modes.add('v', user.nickname)
    }
  }

  removeVoice(user) {
    this.modes.remove('v', user.nickname)
  }

  hasVoice(user) {
    return this.modes.has('v', user.nickname)
  }

  addFlag(flag) {
    this.modes.add(flag)
  }

  removeFlag(flag) {
    this.modes.remove(flag)
  }

  get isPrivate() {
    return this.modes.has('p')
  }

  get isSecret() {
    return this.modes.has('s')
  }

  get isInviteOnly() {
    return this.modes.has('i')
  }

  get isModerated() {
    return this.modes.has('m')
  }

  inspect() {
    return this.toString();
  }
  toString() {
    return `
      channel name: ${this.name}
             topic: ${this.topic}
             users: ${this.users.length}
              ${this.users.map(u => `- ${u.nickname}`).join('\n')}
    `;
  };
}

module.exports = Channel;