const TextBasedChannel = require('./interface/TextBasedChannel');
const Role = require('./Role');
const EvaluatedPermissions = require('./EvaluatedPermissions');
const Constants = require('../util/Constants');
const Collection = require('../util/Collection');
const Presence = require('./Presence').Presence;

/**
 * Represents a member of a guild on Discord
 * @implements {TextBasedChannel}
 */
class GuildMember {
  constructor(guild, data) {
    /**
     * The Client that instantiated this GuildMember
     * @name GuildMember#client
     * @type {Client}
     * @readonly
     */
    Object.defineProperty(this, 'client', { value: guild.client });

    /**
     * The guild that this member is part of
     * @type {Guild}
     */
    this.guild = guild;

    /**
     * The user that this guild member instance Represents
     * @type {User}
     */
    this.user = {};

    this._roles = [];
    if (data) this.setup(data);

    /**
     * The ID of the last message sent by the member in their guild, if one was sent.
     * @type {?string}
     */
    this.lastMessageID = null;
  }

  setup(data) {
    /**
     * Whether this member is deafened server-wide
     * @type {boolean}
     */
    this.serverDeaf = data.deaf;

    /**
     * Whether this member is muted server-wide
     * @type {boolean}
     */
    this.serverMute = data.mute;

    /**
     * Whether this member is self-muted
     * @type {boolean}
     */
    this.selfMute = data.self_mute;

    /**
     * Whether this member is self-deafened
     * @type {boolean}
     */
    this.selfDeaf = data.self_deaf;

    /**
     * The voice session ID of this member, if any
     * @type {?string}
     */
    this.voiceSessionID = data.session_id;

    /**
     * The voice channel ID of this member, if any
     * @type {?string}
     */
    this.voiceChannelID = data.channel_id;

    /**
     * Whether this member is speaking
     * @type {boolean}
     */
    this.speaking = false;

    /**
     * The nickname of this guild member, if they have one
     * @type {?string}
     */
    this.nickname = data.nick || null;

    /**
     * The timestamp the member joined the guild at
     * @type {number}
     */
    this.joinedTimestamp = new Date(data.joined_at).getTime();

    this.user = data.user;
    this._roles = data.roles;
  }

  /**
   * The time the member joined the guild
   * @type {Date}
   * @readonly
   */
  get joinedAt() {
    return new Date(this.joinedTimestamp);
  }

  /**
   * The presence of this guild member
   * @type {Presence}
   * @readonly
   */
  get presence() {
    return this.frozenPresence || this.guild.presences.get(this.id) || new Presence();
  }

  /**
   * A list of roles that are applied to this GuildMember, mapped by the role ID.
   * @type {Collection<string, Role>}
   * @readonly
   */
  get roles() {
    const list = new Collection();
    const everyoneRole = this.guild.roles.get(this.guild.id);

    if (everyoneRole) list.set(everyoneRole.id, everyoneRole);

    for (const roleID of this._roles) {
      const role = this.guild.roles.get(roleID);
      if (role) list.set(role.id, role);
    }

    return list;
  }

  /**
   * The role of the member with the highest position.
   * @type {Role}
   * @readonly
   */
  get highestRole() {
    return this.roles.reduce((prev, role) => !prev || role.comparePositionTo(prev) > 0 ? role : prev);
  }

  /**
   * Whether this member is muted in any way
   * @type {boolean}
   * @readonly
   */
  get mute() {
    return this.selfMute || this.serverMute;
  }

  /**
   * Whether this member is deafened in any way
   * @type {boolean}
   * @readonly
   */
  get deaf() {
    return this.selfDeaf || this.serverDeaf;
  }

  /**
   * The voice channel this member is in, if any
   * @type {?VoiceChannel}
   * @readonly
   */
  get voiceChannel() {
    return this.guild.channels.get(this.voiceChannelID);
  }

  /**
   * The ID of this user
   * @type {string}
   * @readonly
   */
  get id() {
    return this.user.id;
  }

  /**
   * The nickname of the member, or their username if they don't have one
   * @type {string}
   * @readonly
   */
  get displayName() {
    return this.nickname || this.user.username;
  }

  /**
   * The overall set of permissions for the guild member, taking only roles into account
   * @type {EvaluatedPermissions}
   * @readonly
   */
  get permissions() {
    if (this.user.id === this.guild.ownerID) return new EvaluatedPermissions(this, Constants.ALL_PERMISSIONS);

    let permissions = 0;
    const roles = this.roles;
    for (const role of roles.values()) permissions |= role.permissions;

    const admin = Boolean(permissions & Constants.PermissionFlags.ADMINISTRATOR);
    if (admin) permissions = Constants.ALL_PERMISSIONS;

    return new EvaluatedPermissions(this, permissions);
  }

  /**
   * Whether the member is kickable by the client user.
   * @type {boolean}
   * @readonly
   */
  get kickable() {
    if (this.user.id === this.guild.ownerID) return false;
    if (this.user.id === this.client.user.id) return false;
    const clientMember = this.guild.member(this.client.user);
    if (!clientMember.hasPermission(Constants.PermissionFlags.KICK_MEMBERS)) return false;
    return clientMember.highestRole.comparePositionTo(this.highestRole) > 0;
  }

  /**
   * Whether the member is bannable by the client user.
   * @type {boolean}
   * @readonly
   */
  get bannable() {
    if (this.user.id === this.guild.ownerID) return false;
    if (this.user.id === this.client.user.id) return false;
    const clientMember = this.guild.member(this.client.user);
    if (!clientMember.hasPermission(Constants.PermissionFlags.BAN_MEMBERS)) return false;
    return clientMember.highestRole.comparePositionTo(this.highestRole) > 0;
  }

  /**
   * Returns `channel.permissionsFor(guildMember)`. Returns evaluated permissions for a member in a guild channel.
   * @param {ChannelResolvable} channel Guild channel to use as context
   * @returns {?EvaluatedPermissions}
   */
  permissionsIn(channel) {
    channel = this.client.resolver.resolveChannel(channel);
    if (!channel || !channel.guild) throw new Error('Could not resolve channel to a guild channel.');
    return channel.permissionsFor(this);
  }

  /**
   * Checks if any of the member's roles have a permission.
   * @param {PermissionResolvable} permission The permission to check for
   * @param {boolean} [explicit=false] Whether to require the roles to explicitly have the exact permission
   * @returns {boolean}
   */
  hasPermission(permission, explicit = false) {
    if (!explicit && this.user.id === this.guild.ownerID) return true;
    return this.roles.some(r => r.hasPermission(permission, explicit));
  }

  /**
   * Checks whether the roles of the member allows them to perform specific actions.
   * @param {PermissionResolvable[]} permissions The permissions to check for
   * @param {boolean} [explicit=false] Whether to require the member to explicitly have the exact permissions
   * @returns {boolean}
   */
  hasPermissions(permissions, explicit = false) {
    if (!explicit && this.user.id === this.guild.ownerID) return true;
    return permissions.every(p => this.hasPermission(p, explicit));
  }

  /**
   * Checks whether the roles of the member allows them to perform specific actions, and lists any missing permissions.
   * @param {PermissionResolvable[]} permissions The permissions to check for
   * @param {boolean} [explicit=false] Whether to require the member to explicitly have the exact permissions
   * @returns {PermissionResolvable[]}
   */
  missingPermissions(permissions, explicit = false) {
    return permissions.filter(p => !this.hasPermission(p, explicit));
  }

  /**
   * Edit a guild member
   * @param {GuildmemberEditData} data The data to edit the member with
   * @returns {Promise<GuildMember>}
   */
  edit(data) {
    return this.client.rest.methods.updateGuildMember(this, data);
  }

  /**
   * Mute/unmute a user
   * @param {boolean} mute Whether or not the member should be muted
   * @returns {Promise<GuildMember>}
   */
  setMute(mute) {
    return this.edit({ mute });
  }

  /**
   * Deafen/undeafen a user
   * @param {boolean} deaf Whether or not the member should be deafened
   * @returns {Promise<GuildMember>}
   */
  setDeaf(deaf) {
    return this.edit({ deaf });
  }

  /**
   * Moves the guild member to the given channel.
   * @param {ChannelResolvable} channel The channel to move the member to
   * @returns {Promise<GuildMember>}
   */
  setVoiceChannel(channel) {
    return this.edit({ channel });
  }

  /**
   * Sets the roles applied to the member.
   * @param {Collection<string, Role>|Role[]|string[]} roles The roles or role IDs to apply
   * @returns {Promise<GuildMember>}
   */
  setRoles(roles) {
    return this.edit({ roles });
  }

  /**
   * Adds a single role to the member.
   * @param {Role|string} role The role or ID of the role to add
   * @returns {Promise<GuildMember>}
   */
  addRole(role) {
    if (!(role instanceof Role)) role = this.guild.roles.get(role);
    return this.client.rest.methods.addMemberRole(this, role);
  }

  /**
   * Adds multiple roles to the member.
   * @param {Collection<string, Role>|Role[]|string[]} roles The roles or role IDs to add
   * @returns {Promise<GuildMember>}
   */
  addRoles(roles) {
    let allRoles;
    if (roles instanceof Collection) {
      allRoles = this._roles.slice();
      for (const role of roles.values()) allRoles.push(role.id);
    } else {
      allRoles = this._roles.concat(roles);
    }
    return this.edit({ roles: allRoles });
  }

  /**
   * Removes a single role from the member.
   * @param {Role|string} role The role or ID of the role to remove
   * @returns {Promise<GuildMember>}
   */
  removeRole(role) {
    if (!(role instanceof Role)) role = this.guild.roles.get(role);
    return this.client.rest.methods.removeMemberRole(this, role);
  }

  /**
   * Removes multiple roles from the member.
   * @param {Collection<string, Role>|Role[]|string[]} roles The roles or role IDs to remove
   * @returns {Promise<GuildMember>}
   */
  removeRoles(roles) {
    const allRoles = this._roles.slice();
    if (roles instanceof Collection) {
      for (const role of roles.values()) {
        const index = allRoles.indexOf(role.id);
        if (index >= 0) allRoles.splice(index, 1);
      }
    } else {
      for (const role of roles) {
        const index = allRoles.indexOf(role instanceof Role ? role.id : role);
        if (index >= 0) allRoles.splice(index, 1);
      }
    }
    return this.edit({ roles: allRoles });
  }

  /**
   * Set the nickname for the guild member
   * @param {string} nick The nickname for the guild member
   * @returns {Promise<GuildMember>}
   */
  setNickname(nick) {
    return this.edit({ nick });
  }

  /**
   * Deletes any DMs with this guild member
   * @returns {Promise<DMChannel>}
   */
  deleteDM() {
    return this.client.rest.methods.deleteChannel(this);
  }

  /**
   * Kick this member from the guild
   * @returns {Promise<GuildMember>}
   */
  kick() {
    return this.client.rest.methods.kickGuildMember(this.guild, this);
  }

  /**
   * Ban this guild member
   * @param {number} [deleteDays=0] The amount of days worth of messages from this member that should
   * also be deleted. Between `0` and `7`.
   * @returns {Promise<GuildMember>}
   * @example
   * // ban a guild member
   * guildMember.ban(7);
   */
  ban(deleteDays = 0) {
    return this.client.rest.methods.banGuildMember(this.guild, this, deleteDays);
  }

  /**
   * When concatenated with a string, this automatically concatenates the user's mention instead of the Member object.
   * @returns {string}
   * @example
   * // logs: Hello from <@123456789>!
   * console.log(`Hello from ${member}!`);
   */
  toString() {
    return `<@${this.nickname ? '!' : ''}${this.user.id}>`;
  }

  // These are here only for documentation purposes - they are implemented by TextBasedChannel
  sendMessage() { return; }
  sendTTSMessage() { return; }
  sendFile() { return; }
  sendCode() { return; }
}

TextBasedChannel.applyToClass(GuildMember);

module.exports = GuildMember;