var Q = require('q');
var oujRedis = require('./oujRedis.js');
var TableHelper = require('./TableHelper.js');
var r2m_configs = require('../../conf/r2m_config.inc.js');
var util = require('util');
var php = require('phpjs');

/**
 * @type {co.co|exports|module.exports}
 */
var co = require('co');
/**
 * @type {Redis2MySql}
 */
var that;

/**
 * 基本类，提供增删改查
 * @param {string} dbKey
 * @author benzhan
 */
function Redis2MySql(tableName, dbKey, cacheKey) {
    this.tableName = tableName;
    this.dbKey = dbKey || 'default';
    this.cacheKey = cacheKey || 'default';
    this.cacheInfo = r2m_configs[this.dbKey][tableName];
    if (!this.cacheInfo) {
        throw new Error("redis没配置table name:" + tableName, CODE_REDIS_ERROR);
    }

    /**
     * @type {TableHelper}
     */
    this.objTable = new TableHelper(tableName, this.dbKey);
    /**
     * @type {Redis}
     */
    this.objRedis = oujRedis.init(this.cacheKey);
    that = this;

    return this;
}

/**
 * 获取行的key
 * @param args
 * @returns {string}
 * @private
 */
Redis2MySql.prototype._getRowKey = function(args) {
    var key = this.cacheInfo['key'];
    var keys = key.split(',');
    var cacheKeys = [];
    for (var i in keys) {
        var key = keys[i].trim();
        if (args[key]) {
            if (util.isArray(args[key])) {
                cacheKeys.push(key + "=" + join('|', args[key]));
            } else {
                cacheKeys.push(key + "=" + args[key]);
            }
        }
    }

    var cacheKey = this.tableName + ":row";
    if (cacheKey) {
        return cacheKey + ':' + cacheKeys.join(':');
    } else {
        return cacheKey;
    }
}

/**
 * 获取getAll的key
 * @param args
 * @returns {string}
 * @private
 */
Redis2MySql.prototype._getAllKey = function(args) {
    var cacheKey = this.tableName + ":all";
    var otherCacheKey = cacheKey + ":others";

    var key = this.cacheInfo['all_key'];
    if (key) {
        var keys = php.explode(',', key);
        var cacheKeys = [];
        for (var i in keys) {
            var key = keys[i].trim();
            if (util.isArray(args[key]) || typeof args[key] == 'undefined' || args[key] === null) {
                // 如果有数组，或者有key不存在，则归类到others
                return otherCacheKey;
            } else {
                cacheKeys.push(key + "=" + args[key]);
            }
        }

        if (cacheKeys) {
            return cacheKey + ':' + cacheKeys.join(':');
        } else {
            return otherCacheKey;
        }
    } else {
        return otherCacheKey;
    }
}

/**
 * 获取一个key的数据
 * @param where
 * @return <NULL, array>
 * @public
 */
Redis2MySql.prototype.getRow = function getRow(where) {
    var cacheKey = this._getRowKey(where);
    var deferred = co(function*() {
        var data = yield that.objRedis.hgetall(cacheKey);
        if (php.empty(data)) {
            // 从数据库重建
            var row = yield that.objTable.getRow(where);
            if (!php.empty(row)) {
                // 设置缓存，无需等待成功就能返回
                that._setRowCache(row);
            }
            return row;
        } else {
            return data;
        }
    });

    return deferred;
}

/**
 * 读取多行数据
 * @param where
 * @param keyWord 查询关键字, array('_field', '_where', '_limit', '_sortKey', '_sortDir', '_lockRow', '_tableName')
 * @param  bool updateList 是否强制更新缓存
 * @return array:
 * @public
 */
Redis2MySql.prototype.getAll = function(where, keyWord, updateList) {
    var args = php.array_merge(where, keyWord);
    var key = php.http_build_query(args);
    if (key.length > 32) {
        key = php.md5(key);
    } else {
        key = php.http_build_query(args);
    }

    return co(function*() {
        var cacheKey = that._getAllKey(where) + ":" + key;
        if (!updateList) {
            var data = yield that.objRedis.get(cacheKey)
            if (data) {
                return JSON.parse(data);
            }
        }

        var data = yield that.objTable.getAll(where, keyWord);

        // 以下内容只是用来同步redis用的，可以异步跳过
        var pipeline = that.objRedis.pipeline();
        pipeline.set(cacheKey, JSON.stringify(data));
        if (that.cacheInfo['ttl'] > 0) {
            pipeline.expire(cacheKey, that.cacheInfo['ttl']);
        }
        pipeline.exec();

        return data;
    });
}


/**
 * 增加一行数据
 * @param args
 * @param boolean updateList
 * @return int
 * @public
 */
Redis2MySql.prototype.addObject = function addObject(args, updateList) {
    updateList = updateList === false ? updateList : true;

    var deferred = co(function*() {
        var ret = yield that.objTable.addObject(args);
        if (updateList) {
            that.delListCache(args);
        }

        return ret;
    });

    return deferred;
}

/**
 * 删除列表的缓存
 * @param where
 * @public
 */
Redis2MySql.prototype.delListCache = function(where) {
    var cacheKey = that._getAllKey(where);
    var otherKey = this.tableName + ":all:others";
    var deferred = co(function*() {
        var keys = [];
        if (cacheKey === otherKey) {
            // 需要清除所有key删除
            cacheKey = that.tableName + ":all";
            keys = yield that.objRedis.keys(cacheKey + '*');
        } else {
            // 除了删除当前keys，还需要删除others
            keys = yield that.objRedis.keys(cacheKey + '*');
            var keys1 = yield that.objRedis.keys(otherKey + '*');
            keys = php.array_merge(keys, keys1);
        }

        if (keys.length > 0) {
            that.objRedis.del(keys);
        }

        return 1;
    });

    return deferred;
}

/**
 * 设置行的缓存
 * @param args
 * @returns {Array|{index: number, input: string}|*|{arity, flags, keyStart, keyStop, step}}
 * @private
 */
Redis2MySql.prototype._setRowCache = function(args) {
    var cacheKey = this._getRowKey(args);
    if (!cacheKey) {
        var msg = "没设置key:cacheKey," . JSON.stringify(this.cacheInfo);
        throw new Error(msg, CODE_REDIS_ERROR);
    }

    var pipeline = this.objRedis.pipeline();
    pipeline.hmset(cacheKey, args);
    if (this.cacheInfo['ttl'] > 0) {
        pipeline.expire(cacheKey, this.cacheInfo['ttl']);
    }

    return pipeline.exec();
}

/**
 * 更新行缓存
 * @param args
 * @returns {*}
 * @private
 */
Redis2MySql.prototype._updateRowCache = function(args) {
    var cacheKey = this._getRowKey(args);
    if (!cacheKey) {
        var msg = "没设置key:cacheKey," . JSON.stringify(this.cacheInfo);
        throw new Error(msg, CODE_REDIS_ERROR);
    }

    var deferred = co(function *() {
        var flag = yield that.objRedis.exists(cacheKey);
        if (flag == 1) {
            var pipeline = that.objRedis.pipeline();
            pipeline.hmset(cacheKey, args);

            if (that.cacheInfo['ttl'] > 0) {
                pipeline.expire(cacheKey, that.cacheInfo['ttl']);
            }

            yield pipeline.exec();

            return 1;
        }
    });

    return deferred;
}


/**
 * 修改一个key的数据
 * @param args 更新的内容
 * @param where 更新的条件
 * @param boolean updateList
 * @return int 影响行数
 * @public
 */
Redis2MySql.prototype.updateObject = function(args, where, updateList) {
    updateList = updateList === false ? updateList : true;

    var deferred = co(function*() {
        var result = yield that.objTable.updateObject(args, where);
        args = php.array_merge(args, where);
        if (result.affectedRows > 0) {
            yield that._updateRowCache(args);

            if (updateList) {
                that.delListCache(where);
            }
        }

        return result;
    });

    return deferred;
}


/**
 * 设置一个key的数据
 * @param args
 * @param boolean updateList
 * @return int 影响行数
 * @public
 */
Redis2MySql.prototype.replaceObject = function(args, updateList) {
    var deferred = co(function*() {
        var result = yield that.objTable.replaceObject(args);
        yield that._setRowCache(args);

        if (updateList) {
            that.delListCache(args);
        }

        return result;
    });

    return deferred;
}

/**
 * 删除数据
 * @param array $where
 * @throws RedisException
 * @return unknown
 * @public
 */
Redis2MySql.prototype.delObject = function(where, updateList) {
    updateList = updateList === false ? updateList : true;

    var deferred = co(function*() {
        var result = yield that.objTable.delObject(where);

        that._delRowCache(where);
        if (updateList) {
            that.delListCache(where);
        }

        return result;
    });

    return deferred;
}

/**
 * 删除行的缓存
 * @param where
 * @throws RedisException
 * @private
 */
Redis2MySql.prototype._delRowCache = function(where) {
    var cacheKey = this._getRowKey(where);
    if (!cacheKey) {
        var msg = "没设置key:cacheKey," . JSON.stringify(this.cacheInfo);
        throw new Error(msg, CODE_REDIS_ERROR);
    }

    return this.objRedis.del(cacheKey);
}

/**
 * 关闭连接
 * @public
 */
Redis2MySql.prototype.close = function() {
    if (this.objTable) {
        this.objTable.close();
    }

    if (this.objRedis) {
        this.objRedis.disconnect();
    }
}

module.exports = Redis2MySql;