/**
 * 会话成员模型。
 */
"use strict";

let RedisModel = require('./../redis.model.js');
let ModelUtil = require('../../util/model.util');
let RedisClient = require('../../repository/redis/redis.client.js');
let ParticipantRepo = require('../../repository/mysql/participant.repo');

let log = require('../../util/log.js');
let redis = RedisClient.redisClient().connection;

const REDIS_KEYS = require('../../include/commons').REDIS_KEYS;

class Participants extends RedisModel {
    constructor() {
        super();
    }

    /**
     * 获取会话的成员列表，直接从MySQL获取。
     *
     * @param sessionId
     */
    getParticipants(sessionId) {
        let self = this;

        ParticipantRepo.findAll(sessionId, function (err, participants) {
            if (err) {
                ModelUtil.emitError(self.eventEmitter, "Get session participants error", err);
                return;
            }

            ModelUtil.emitOK(self.eventEmitter, participants);
        });
    }

    /**
     * 获取所有成员的头像。
     *
     * @param sessionId
     */
    getParticipantsAvatar(sessionId) {
        let self = this;

        ParticipantRepo.findAllAvatars(sessionId, function (err, participantsAvatars) {
            if (err) {
                ModelUtil.emitError(self.eventEmitter, "Get session participant's avatars error", err);
                return;
            }

            ModelUtil.emitOK(self.eventEmitter, participantsAvatars);
        })
    }

    /**
     * 会话中是否存在指定成员
     *
     * @param sessionId
     * @param userId
     * @param handler
     */
    existsParticipant(sessionId, userId, handler) {
        let participantsRoleKey = RedisModel.makeRedisKey(REDIS_KEYS.SessionParticipantsRole, sessionId);
        redis.hgetAsync(participantsRoleKey, userId).then(function (res) {
            if (false) {
                // get from redis
                handler(null, true);
            } else {
                // get from mysql
                ParticipantRepo.existsParticipant(sessionId, userId, handler);
            }
        })
    }


    /**
     * 获取P2P成员所在会话
     *
     * @param patient
     * @param doctor
     * @param handler
     */
    getSessionIdByParticipants(patient, doctor, handler) {
        ParticipantRepo.findSessionIdByParticipantIds(patient, doctor, handler);
    }

    /**
     * 将成员写入redis
     *
     * @param sessionId 会话ID
     * @param participantsArray 会话参与者集合
     * @param createDate 创建日期
     * @param handler 回调
     */
    static saveParticipantsToRedis(sessionId, participantsArray, createDate, handler) {
        // 构造会话，成员及成员角色zset, hash所需要的数据
        let userSessions = {};
        let sessionParticipants = [];
        let sessionParticipantsRoles = [];

        participantsArray.forEach(function (item) {
            let tokens = item.split(":");
            userSessions[RedisModel.makeRedisKey(REDIS_KEYS.UserSessions, tokens[0])] = [createDate.getTime(), sessionId];

            sessionParticipants.push(createDate.getTime());
            sessionParticipants.push(tokens[0]);

            sessionParticipantsRoles.push(tokens[0], tokens[1]);
        });

        // 向会话成员、会话成员角色集合中添加数据
        let sessionParticipantsKey = RedisModel.makeRedisKey(REDIS_KEYS.SessionParticipants, sessionId);
        let sessionParticipantsRoleKey = RedisModel.makeRedisKey(REDIS_KEYS.SessionParticipantsRole, sessionId);
        let multi = redis.multi()
            .zadd(sessionParticipantsKey, sessionParticipants)
            .hmset(sessionParticipantsRoleKey, sessionParticipantsRoles);

        // 更新用户参与的会话列表
        for (let key in userSessions) {
            multi = multi.zadd(key, userSessions[key]);
        }

        multi.execAsync()
            .then(function (res) {
                handler(true);
            });
    }

    /**
     * mysql成员创建
     *
     * @param sessionId
     * @param users
     * @param handler
     */
    static saveParticipantsToMysql(sessionId, users, handler) {
        return ParticipantRepo.saveParticipantsToMysql(sessionId, users, handler);
    }


    /**
     * 移除成员
     * @param sessionId
     * @param userId
     */
    removeUser(sessionId, userId) {
        let self = this;
        let participants_key = RedisModel.makeRedisKey(REDIS_KEYS.SessionParticipants, sessionId);
        let user_session_key = RedisModel.makeRedisKey(REDIS_KEYS.UsersSessions, userId);

        // 移除会话中的成员信息,用户的Session信息及MySQL中的记录
        redis.multi()
            .zrem(participants_key, userId)
            .zrem(user_session_key, sessionId)
            .execAsync()
            .then(function (res) {
                self.deleteUserFromMysql(sessionId, userId);
                ModelUtil.emitOK(self.eventEmitter, {});
            })
            .catch(function (err) {
                ModelUtil.emitError(self.eventEmitter, {message: "成员删除失败: " + err});
            });
    }

    /**
     * 更新用户在MUC模式中的状态
     * @param sessionId 会话ID
     * @param user 用户
     * @param role 变更状态
     */
    updateUser(sessionId, user, role) {
        let participantsRoleKey = RedisModel.makeRedisKey(REDIS_KEYS.SessionParticipantsRole, sessionId);
        redis.hsetAsync(participantsRoleKey, user, role)
            .then(function (res) {
                ParticipantRepo.updateParticipant(sessionId, user, role, function (err, res) {
                });
            })
    }

    /**
     * 添加讨论组成员
     * @param sessionId
     * @param user
     */
    addUser(sessionId, user) {
        let self = this;
        let users = [user];
        self.saveParticipantsToRedis(sessionId, users, new Date(), function (res) {
            if (res) {
                self.saveParticipantsToMysql(sessionId, users);
            } else {
                ModelUtil.emitOK(self.eventEmitter, {message: "成员添加失败"});
            }
        })
    }

    /**
     * user从数据库中删除
     * @param sessionId 会话
     * @param user 用户
     */
    deleteUserFromMysql(sessionId, user) {
        ParticipantRepo.deleteUserFromMysql(sessionId, user);
    }
}

// Expose class
module.exports = Participants;