'use strict';

const { Channel } = require('./Channel');
const { Error } = require('../errors');
const { Collection } = require('discord.js');
const { Message } = require('./Message');
const MessageManager = require('../managers/MessageManager');
const User = require('./User');
const DataResolver = require('../util/DataResolver');
const TextBasedChannel = require('./interfaces/TextBasedChannel');
const Invite = require('./Invite');


/**
 * Represents a Partial Group DM Channel on Discord.
 * @extends {Channel}
 */
class PartialGroupDMChannel extends Channel {
  constructor(client, data) {
    super(client, data);
    /**
     * The name of this Group DM Channel
     * @type {?string}
     */
    this.name = data.name;

    /**
     * The hash of the channel icon
     * @type {?string}
     */
    this.icon = data.icon;

    /**
     * Recipient data received in a {@link PartialGroupDMChannel}.
     * @typedef {Object} PartialRecipient
     * @property {string} username The username of the recipient
     */

    /**
     * The recipients of this Group DM Channel.
     * @type {PartialRecipient[]}
     */
    this.recipients = new Collection();

    /**
     * Messages data
     * @type {Collection}
     */
    this.messages = new MessageManager(this);

    /**
     * Last Message ID
     * @type {?snowflake<Message.id>}
     */
    this.lastMessageId = null;

    /**
     * Last Pin Timestamp
     * @type {UnixTimestamp}
     */
    this.lastPinTimestamp = null;

    /**
     * The owner of this Group DM Channel
     * @type {?User}
     * @readonly
     */
    this.owner = client.users.cache.get(data.owner_id);
    this.ownerId = data.owner_id;

    /**
     * Invites fetch
     */
    this.invites = new Collection();

    this._setup(client, data);
  }

  /**
   * 
   * @param {Discord.Client} client 
   * @param {object} data 
   * @private
   */
  _setup(client, data) {
    if ('recipients' in data) {
      Promise.all(
        data.recipients.map((recipient) => {
          this.recipients.set(
            recipient.id,
            client.users.cache.get(data.owner_id) || recipient,
          );
        }),
      );
    }
    if ('last_pin_timestamp' in data) {
      const date = new Date(data.last_pin_timestamp);
      this.lastPinTimestamp = date.getTime();
    }
    if ('last_message_id' in data) {
      this.lastMessageId = data.last_message_id;
    }
  }

  /**
   * 
   * @param {Object} data name, icon
   * @returns 
   * @private
   */
  async edit(data) {
    const _data = {};
    if ('name' in data) _data.name = data.name?.trim() ?? null;
    if (typeof data.icon !== 'undefined')
      _data.icon = await DataResolver.resolveImage(data.icon);
    const newData = await this.client.api.channels(this.id).patch({
      data: _data,
    });

    return this.client.actions.ChannelUpdate.handle(newData).updated;
  }

  /**
   * The URL to this channel's icon.
   * @param {StaticImageURLOptions} [options={}] Options for the Image URL
   * @returns {?string}
   */
  iconURL({ format, size } = {}) {
    return (
      this.icon &&
      this.client.rest.cdn.GDMIcon(this.id, this.icon, format, size)
    );
  }

  async addMember(user) {
    if (this.ownerId !== this.client.user.id)
      return Promise.reject(new Error('NOT_OWNER_GROUP_DM_CHANNEL'));
    if (!user instanceof User)
      return Promise.reject(
        new TypeError('User is not an instance of Discord.User'),
      );
    if (this.recipients.get(user.id)) return Promise.reject(new Error('USER_ALREADY_IN_GROUP_DM_CHANNEL'));
    //
    await this.client.api.channels[this.id].recipients[user.id].put();
    this.recipients.set(user.id, user);
    return this;
  }

  async removeMember(user) {
    if (this.ownerId !== this.client.user.id)
      return Promise.reject(new Error('NOT_OWNER_GROUP_DM_CHANNEL'));
    if (!user instanceof User)
      return Promise.reject(
        new TypeError('User is not an instance of Discord.User'),
      );
    if (!this.recipients.get(user.id)) return Promise.reject(new Error('USER_NOT_IN_GROUP_DM_CHANNEL'));
    await this.client.api.channels[this.id].recipients[user.id].delete();
    this.recipients.delete(user.id);
    return this;
  }

  setName(name) {
    return this.edit({ name });
  }

  setIcon(icon) {
    return this.edit({ icon });
  }

  async getInvite() {
    const inviteCode = await this.client.api.channels(this.id).invites.post({
			data: {
				max_age: 86400,
			},
		});
    const invite = new Invite(this.client, inviteCode);
    this.invites.set(invite.code, invite);
    return invite;
  }

  async fetchInvite(force = false) {
    if (this.ownerId !== this.client.user.id)
      return Promise.reject(new Error('NOT_OWNER_GROUP_DM_CHANNEL'));
    if (!force && this.invites.size) return this.invites;
    const invites = await this.client.api.channels(this.id).invites.get();
    await Promise.all(invites.map(invite => this.invites.set(invite.code, new Invite(this.client, invite))));
    return this.invites;
  }

  async removeInvite(invite) {
    if (this.ownerId !== this.client.user.id)
      return Promise.reject(new Error('NOT_OWNER_GROUP_DM_CHANNEL'));
    if (!invite instanceof Invite)
      return Promise.reject(new TypeError('Invite is not an instance of Discord.Invite'));
    await this.client.api.channels(this.id).invites[invite.code].delete();
    this.invites.delete(invite.code);
    return this;
  }

  // These are here only for documentation purposes - they are implemented by TextBasedChannel
  /* eslint-disable no-empty-function */
  get lastMessage() { }
  get lastPinAt() { }
  send() { }
  sendTyping() { }
}

TextBasedChannel.applyToClass(PartialGroupDMChannel, false);

module.exports = PartialGroupDMChannel;