/*
 * @Author: HonorLee
 * @Version 1.0
 * @LastUpdate 2018/6/19
 * @License MIT
*/
'use strict'
var Session = {
    set:function(key,value,callback){
        callback = Manager.buildCallback(callback);
        if(!key || value==null) return callback.call(this,'Session key or value is empty',null);
        let _this = this;
        let session = {};

        session.id = MD5(new Date().getTime()+''+Math.floor(Math.random()*9000+1000));
        session.data = {};
        session.data[key] = value;
        session.expire = Config.SessionExpire*60;
        session.expireTime = new Date().getTime()+session.expire*1000;
        session.autoRenewExpire = Config.SessionExpire*60;

        Manager.set(session,function(err){
            if(err) return callback.call(_this,'Session set err;',null);
            callback.call(_this,null,session);
        });
    },
    setExpireTime:function(sessionid,expire,autoRenewExpire,callback){
        let _this = this;
        callback = Manager.buildCallback(callback);
        if(!sessionid) return callback.call(this,'Session id is empty',null);
        if(!expire) return callback.call(this,'Session expire must bigger than 0',null);
        Session.get(sessionid,function(err,data){
            if(err || !data) return callback.call(this,'Session is gone',null);
            let session = data;
            session.expire = expire*60;
            autoRenewExpire = autoRenewExpire*1;
            if(autoRenewExpire>0) session.autoRenewExpire = autoRenewExpire*60;
            Manager.set(session,function(err){
                if(err){
                    LOGGER.error(err);
                    callback.call(_this,'Session set expire error',null);
                }else{
                    callback.call(_this,null,session);
                }
            })
        });

    },
    update:function(sessionid,key,value,callback){
        callback = Manager.buildCallback(callback);
        if(!sessionid || !key || value==null) return callback.call(this,'Session id,key or value is empty',null);
        let _this = this;
        Manager.get(sessionid,function(err,result){
            let session;
            if(err || result == null){
                session = {id:sessionid,data:{}};
            }else{
                session = result;
            }

            if(err || result == null || Config.Session.AutoRefresh){
                session.expire = session.autoRenewExpire;
                session.expireTime = new Date().getTime()+session.expire*1000;
            }

            session.data[key] = value;
            Manager.set(session,function(err){
                if(err) return callback.call(_this,'Session set error');
                callback.call(_this,null,session)
            });
        });
    },
    get:function(sessionid,callback){
        callback = Manager.buildCallback(callback);
        if(!sessionid) return callback.call(this,'Session id is empty',null);
        let _this = this;
        Manager.get(sessionid,function(err,result){
            callback.call(_this,null,result);
        });
    },
    getKeyValue:function(sessionid,key,callback){
        callback = Manager.buildCallback(callback);
        if(!sessionid || !key) return callback.call(this,'Session id or key is empty',null);
        let _this = this;
        Session.get(sessionid,function(err,result){
            if(err || !result) return callback.call(_this,null);
            callback.call(_this,null,result.data[key]);
        });
    },
    clear:function(sessionid){
        if(!sessionid) return;
        Manager.clear(sessionid);
    },
    instance:function(sessionID,callback){
        return new Instance(sessionID,callback);
    }
};
module.exports = Session;

var Manager = {
    get:function(sessionid,callback){
        let session;
        if(Config.Session.StoreType.toLowerCase()=='memcache' && Config.Database.Memcache.on && Memcache){
            Memcache.get('session_'+sessionid,function(err,result){
                if(err) return callback(err);
                session = result;
                callback(null,result);
                if(session && Config.Session.AutoRefresh){
                    session.expire = session.autoRenewExpire;
                    session.expireTime = new Date().getTime()+session.expire*1000;
                    Manager.set(session,null);
                }
            });
        }else{
            try{
                session = JSON.parse(FILE.readFileSync(Core.Path.Session + '/' + sessionid,'UTF-8'));
            }catch(e){}
            if(session && session.expireTime){
                if(new Date().getTime()>session.expireTime){
                    if(Config.Session.AutoRefresh){
                        session.expire = session.autoRenewExpire;
                        session.expireTime = new Date().getTime()+session.expire*1000;
                        Manager.set(session,null);
                    }else{
                        session = null;
                        Manager.clear(sessionid);
                    }
                }
            }
            if(callback) callback(null,session);
        }

    },
    set:function(session,callback){
        if(Config.Session.StoreType.toLowerCase()=='memcache' && Config.Database.Memcache.on && Memcache){
            Memcache.set('session_'+session.id,session,session.expire,function(err){
                if(err){
                    Logger.error(err);
                    if(callback) callback(err);
                    return;
                }
                if(callback) callback();
            });
        }else{
            FILE.writeFileSync(Core.Path.Session + '/' + session.id,JSON.stringify(session),'UTF-8');
            if(callback) callback();
        }
    },
    clear:function(sessionid){
        if(Config.Session.StoreType.toLowerCase()=='memcache' && Config.Database.Memcache.on && Memcache){
            Memcache.del('session_'+sessionid);
        }else{
            try{
                FILE.rmdirSync(Core.Path.Session + '/' + sessionid);
            }catch(e){}
        }
    },
    buildCallback:function(callback){
        if(callback && typeof callback=='function') return callback;
        return function(){};
    }
}

var Instance = function(sessionID,callback){
    var _data;
    var _sessionID = sessionID;
    var _this = this;
    this.sessionID = _sessionID;
    this.get = function(key){
        return _data[key];
    }
    this.set = function(key,value){
        _data[key] = value;
        Session.update(_sessionID,key,value);
    }
    this.setExpireTime = function(expire,autoRenewExpire){
        Session.setExpireTime(_sessionID,expire,autoRenewExpire);
    }
    if(sessionID){
        Session.get(sessionID,function(err,session){
            if(err || !session){
                Session.set('status',0,function(err,new_session){
                    _data = new_session.data;
                    _this.sessionID = new_session.id;
                    if(callback) callback(new_session.id,_this);
                });
            }else{
                _data = session.data;
                _this.sessionID = session.id;
                if(callback) callback(session.id,_this);
            }
        });
    }else{
        Session.set('status',0,function(err,new_session){
            _data = new_session.data;
            _sessionID = new_session.id;
            _this.sessionID = new_session.id;
            if(callback) callback(new_session.id,_this);
        });
    }
    return this;
}