text: const Collection = require('../util/Collection');
  const Emoji = require('./Emoji');
  const ReactionEmoji = require('./ReactionEmoji');
  
  /**
   * Represents a reaction to a message.
   */
  class MessageReaction {
    constructor(message, emoji, count, me) {
      /**
       * The message that this reaction refers to
       * @type {Message}
       */
      this.message = message;
  
      /**
       * Whether the client has given this reaction
       * @type {boolean}
       */
      this.me = me;
  
      /**
       * The number of people that have given the same reaction
       * @type {number}
       */
      this.count = count || 0;
  
      /**
       * The users that have given this reaction, mapped by their ID
       * @type {Collection<Snowflake, User>}
       */
      this.users = new Collection();
  
      this._emoji = new ReactionEmoji(this, emoji.name, emoji.id);
    }
  
    /**
     * The emoji of this reaction, either an Emoji object for known custom emojis, or a ReactionEmoji
     * object which has fewer properties. Whatever the prototype of the emoji, it will still have
     * `name`, `id`, `identifier` and `toString()`
     * @type {Emoji|ReactionEmoji}
     * @readonly
     */
    get emoji() {
      if (this._emoji instanceof Emoji) return this._emoji;
      // Check to see if the emoji has become known to the client
      if (this._emoji.id) {
        const emojis = this.message.client.emojis;
        if (emojis.has(this._emoji.id)) {
          const emoji = emojis.get(this._emoji.id);
          this._emoji = emoji;
          return emoji;
        }
      }
      return this._emoji;
    }
  
    /**
     * Removes a user from this reaction.
     * @param {UserResolvable} [user=this.message.client.user] The user to remove the reaction of
     * @returns {Promise<MessageReaction>}
     */
    remove(user = this.message.client.user) {
      const message = this.message;
      const userID = this.message.client.resolver.resolveUserID(user);
      if (!userID) return Promise.reject(new Error('Couldn\'t resolve the user ID to remove from the reaction.'));
      return message.client.rest.methods.removeMessageReaction(
        message, this.emoji.identifier, userID
      );
    }
  
    /**
     * Fetch all the users that gave this reaction. Resolves with a collection of users, mapped by their IDs.
     * @param {number} [limit=100] The maximum amount of users to fetch, defaults to 100
     * @param {Object} [options] Options to fetch users
     * @param {Snowflake} [options.before] Limit fetching users to those with an id lower than the supplied id
     * @param {Snowflake} [options.after] Limit fetching users to those with an id greater than the supplied id
     * @returns {Promise<Collection<Snowflake, User>>}
     */
    fetchUsers(limit = 100, { after, before } = {}) {
      const message = this.message;
      return message.client.rest.methods.getMessageReactionUsers(
        message, this.emoji.identifier, { after, before, limit }
      ).then(users => {
        for (const rawUser of users) {
          const user = this.message.client.dataManager.newUser(rawUser);
          this.users.set(user.id, user);
        }
        return this.users;
      });
    }
  }
  
  module.exports = MessageReaction;
  