const fs = require('fs');
const os = require("os");
const path = require("path");
let rfs = require('rotating-file-stream');
const mkdirp = require('mkdirp');
const onHeaders = require('on-headers');

const dateFMT = 'yyyymmdd HH:MM:ss.l';
const dateFMT_SQL = 'yyyy-mm-dd HH:MM:ss.l';
const fileFMT = 'yyyymmddHHMMss';
const dateFormat = require('dateformat');
const sqlite3 = require('sqlite3').verbose();
process.env.pm_id = process.env.pm_id | '0';
let db;
//const db = new sqlite3.Database( path.resolve(__dirname, `statDB/stat_${process.env.pm_id}.db`) );
const cron = require('node-cron');
// import cron from 'node-cron';

let conf = {};
conf.projectName = 'PROJECT_NAME';

conf.log = {};
conf.log.time = null;     //min
conf.log.size = null;   //maxsize per file, k
conf.log.path = './appLogPath/';
conf.log.level = 'debug'; //debug,info,warn,error
conf.log.console = false;
conf.log.file = true;

conf.summary = {};
conf.summary.time = 15;
conf.summary.size = null;
conf.summary.path = './summaryPath/';
conf.summary.console = false;
conf.summary.file = true;

conf.detail = {};
conf.detail.time = 15;
conf.detail.size = null;
conf.detail.path = './detailPath/';
conf.detail.console = false;
conf.detail.file = true;

conf.stat = {};
conf.stat.time = 15;
conf.stat.size = 15;
conf.stat.path = './statPath/';
conf.stat.mode = 0; //0 == file, 1== :memory:
conf.stat.pathDB = undefined; //optional, folder path DB
conf.stat.statInterval = 15;
conf.stat.console = false;
conf.stat.file = true;
// conf.stat.process = [{
//     name:'stat_name_1',
//     threshold: 10
// },{
//     name:'stat_name_2',
//     threshold: 10
// }]; 
// conf.alarm = {};
// conf.alarm.time = 15;
// conf.alarm.size = 15;
// conf.alarm.path = './alarmPath/';
// conf.alarm.console = false;
// conf.alarm.file = true;

let log = {
    initLog: false
}



function getLogFileName(date, index) {
    return os.hostname() + '_'
        + conf.projectName
        + (date ? ('_' + dateFormat(date, fileFMT) + '.' + index) : '')
        + '.log';
}
function getStatFileName(date, index) {
    return os.hostname() + '_'
        + conf.projectName
        + (date ? ('_' + dateFormat(date, fileFMT) + '.' + index) : '')
        + '.' + process.env.pm_id
        + '.stat';
}
function getSummaryFileName(date, index) {
    return os.hostname() + '_'
        + conf.projectName
        + (date ? ('_' + dateFormat(date, fileFMT) + '.' + index) : '')
        + '.summary';
}
function getDetailFileName(date, index) {
    return os.hostname() + '_'
        + conf.projectName
        + (date ? ('_' + dateFormat(date, fileFMT) + '.' + index) : '')
        + '.detail';
}
function getConf(type) {
    if (type === 'app') return conf['log'];
    else if (type === 'stt') return conf['stat'];
    else if (type === 'smr') return conf['summary'];
    else if (type === 'dtl') return conf['detail'];
}
function generator(type) {
    return (time, index) => {
        if (type === 'app') return getLogFileName(time, index);
        else if (type === 'stt') return getStatFileName(time, index);
        else if (type === 'smr') return getSummaryFileName(time, index);
        else if (type === 'dtl') return getDetailFileName(time, index);
    }
}
function createOpts(conf) {
    let o = {
        path: conf.path
    };
    if (conf.size) o.size = conf.size + 'K';
    if (conf.time) o.interval = conf.time + 'm';
    return o;
}
function createStream(type) {
    let conf = getConf(type);
    let stream = rfs(generator(type), createOpts(conf));
    return stream;
}

var streamTask = {
    app: [],
    stt: [],
    smr: [],
    dtl: []
};

function toStr(txt) {
    // console.log(txt + 'txt instanceof Object ' + (txt instanceof Object));
    // console.log(txt + 'txt instanceof Array ' + (txt instanceof Array));
    
    if ( txt instanceof Error ) {
        return txt.message + ', ' + txt.stack;
    } else if ( txt instanceof Object ) {
        return JSON.stringify(txt);
    } else {
        return txt;
    }
}


function printTxtOrError( _txt ){
    if (_txt instanceof Error) {
        return _txt;
    }else{
        return _txt;
    }
}

function processApplog(lvlAppLog, ..._txt) {
    let session;
    let rtxt = '';
    if (_txt instanceof Array) {
        if (_txt.length > 1) {
            //index0 == session, index1 == text
            session = _txt[0];
            rtxt = toStr(_txt[1])
            for (let i = 2; i < _txt.length; i++) {
                rtxt += ' ' + toStr(_txt[i]);
            }
        } else {
            session = '';
            rtxt = _txt[0];
        }
    } else {

        session = '';
        rtxt = toStr(_txt);
    }
    return `${getDateTimeLogFormat(new Date())}|${session}|${lvlAppLog}|${rtxt}`;
}


function write(type, txt) {
    for (const stream of streamTask[type]) {
        stream.write(txt + '\r\n');
    }
}

function getDateTimeLogFormat(currentDates) {
    var years = currentDates.getFullYear();
    var months = currentDates.getMonth() + 1;
    var day = currentDates.getDate();
    var hours = currentDates.getHours();
    var minutes = currentDates.getMinutes();
    var second = currentDates.getSeconds();
    var millisecs = currentDates.getMilliseconds();
    var monthFormatted = months < 10 ? "0" + months : months;
    var dayFormatted = day < 10 ? "0" + day : day;
    var hourFormatted = hours < 10 ? "0" + hours : hours;
    var minFormatted = minutes < 10 ? "0" + minutes : minutes;
    var secFormatted = second < 10 ? "0" + second : second;
    var milliFormatted = null;

    if (millisecs < 10) {
        milliFormatted = "00" + millisecs;
    }
    else if (millisecs < 100) {
        milliFormatted = "0" + millisecs;
    }
    else {
        milliFormatted = millisecs;
    }
    var detail = '' + years + monthFormatted + dayFormatted + ' ' + hourFormatted + ':' + minFormatted + ':' + secFormatted + '.' + milliFormatted + '|' + os.hostname() + '|' + conf.projectName;
    return detail;
}





function initDB() {
    if (conf.stat.mode === 0) {
        db = new sqlite3.cached.Database(':memory:');

    } else if (conf.stat.mode === 1) {
        if (!conf.stat.pathDB) {
            conf.stat.pathDB = path.resolve(__dirname, 'statDB');
        }
        if (!fs.existsSync(conf.stat.pathDB)) {
            fs.mkdirSync(conf.stat.pathDB);
        }
        db = new sqlite3.cached.Database(`${conf.stat.pathDB}/stat_${process.env.pm_id}.db`);
    }

    db.serialize(function () {
        db.run("CREATE TABLE IF NOT EXISTS stat (stat_time TEXT, stat_name TEXT);");
    });
}

function initLog() {
    if (conf.log) {
        if (conf.log.file) {
            if (!fs.existsSync(conf.log.path)) {
                //fs.mkdirSync(conf.log.path);                
                mkdirp.sync(conf.log.path);
            }
            streamTask['app'].push(createStream('app'));
        }
        if (conf.log.console) streamTask['app'].push(process.stdout);
    }
    if (conf.stat) {
        if (conf.log.file){
            if (!fs.existsSync(conf.stat.path)) {
                //fs.mkdirSync(conf.stat.path);
                mkdirp.sync(conf.stat.path);
            }
            streamTask['stt'].push(createStream('stt'));
        } 
        if (conf.log.console) streamTask['stt'].push(process.stdout);
    }
    if (conf.summary) {
        if (conf.log.file){
            if (!fs.existsSync(conf.summary.path)) {
                // fs.mkdirSync(conf.summary.path);
                mkdirp.sync(conf.summary.path);
            }
            streamTask['smr'].push(createStream('smr'));
        } 
        if (conf.log.console) streamTask['smr'].push(process.stdout);
    }
    if (conf.detail) {
        if (conf.log.file){
            if (!fs.existsSync(conf.detail.path)) {
                // fs.mkdirSync(conf.detail.path);
                mkdirp.sync(conf.detail.path);
            }
            streamTask['dtl'].push(createStream('dtl'));
        } 
        if (conf.log.console) streamTask['dtl'].push(process.stdout);
    }
}

function addStat(stat_name) {
    db.serialize(function () {
        //db.run("CREATE TABLE lorem (info TEXT, xx TEXT)");
        /*var stmt = db.prepare("INSERT INTO lorem VALUES (?)");
      for (var i = 0; i < 10; i++) {
          stmt.run("Ipsum " + i);
      }
      stmt.finalize();

        db.run("INSERT INTO stat(stat_time, stat_name) VALUES (?)", ['xx',stat_name], function() {
            console.log( 'x' );
             getStat();
        });*/

        /*db.run("INSERT INTO stat VALUES (?,?)", [dateFormat(new Date(), dateFMT_SQL), stat_name], function() {
            getStat();
        });*/

        db.run("INSERT INTO stat VALUES (?,?)", [dateFormat(new Date(), dateFMT_SQL), stat_name]);

        /*db.run("INSERT INTO stat VALUES (DATETIME('now'), '"+stat_name+"')", function() {
            console.log( 'x' );
             getStat();
        });*/


    });

}



//var prevStatDateRange;
function fushStat() {
    var end = new Date();
    end.setMilliseconds(0);

    //var start = new Date(end.getTime());
    //start.setMinutes(end.getMinutes() - conf.log.statTime);

    var en = dateFormat(end, dateFMT_SQL);
    //var st = dateFormat(prevStatDateRange, dateFMT_SQL);

    //prevStatDateRange = end; //assign for next loop
    //console.log(st + '|' + en);
    //var path = getStatFileName(end);

    db.serialize(function () {
        //var stream = fs.createWriteStream(path, { 'flags': 'a' });
        write('stt', en);

        db.each("SELECT stat_name, count(stat_name) as count FROM stat WHERE stat_time < ? group by stat_name order by stat_time", [en], function (err, row) {
            if (err) {
                console.log(err);
                return;
            }
            //console.log(path+' '+ row.stat_name + ' ' + row.count );
            write('stt', row.stat_name + ' ' + row.count);
        });

        db.run("DELETE FROM stat WHERE stat_time < ?", [en]);

        /*db.each("SELECT stat_name, count(stat_name) as count FROM stat WHERE stat_time BETWEEN ? AND ? group by stat_name order by stat_name", [st, en], function (err, row) {
            if (err) {
                console.log(err);
                return;
            }
            //console.log(path+' '+ row.stat_name + ' ' + row.count );
            write(end, 'stt', row.stat_name + ' ' + row.count, false);
        });

        db.run("DELETE FROM stat WHERE stat_time BETWEEN ? AND ?", [st, en]);*/

    });
}

function getIntervalTime(type) {
    if (type === 'app') {
        return conf.log.time;
    } else if (type === 'stt') {
        return conf.stat.time;
    } else if (type === 'smr') {
        return conf.summary.time;
    } else if (type === 'dtl') {
        return conf.detail.time;
    }
    return null;
}



log.stat = function (stat_name) {
    addStat(stat_name);
}

log.debug = function (..._log) {
    if (conf.log.level > 0) return;
    write('app', processApplog('debug', ..._log));
}

log.info = function (..._log) {
    if (conf.log.level > 1) return;
    write('app', processApplog('info', ..._log));
}
log.warn = function (..._log) {
    if (conf.log.level > 2) return;
    write('app', processApplog('warn', ..._log));
}
log.error = function (..._log) {
    if (conf.log.level > 3) return;
    write('app', processApplog('error', ..._log));
}

log.detail = function (detailLog) {
    write('dtl', detailLog);
}


// log.detail = function (session, scenario, identity) {
//     var startTimeDate = new Date();
//     var inputTime;
//     var outputTime;

//     var detailLog = {
//         Session: session,
//         InitInvoke: '', //only equinox platform
//         Scenario: scenario,
//         Identity: identity,
//         InputTimeStamp: null,
//         Input: [],
//         OutputTimeStamp: null,
//         Output: [],
//         ProcessingTime: null,
//         addInputRequest: function (node, cmd, rawData, data) {
//             this.addInput(node, cmd, 'REQ', rawData, data);
//         },
//         addInputResponse: function (node, cmd, rawData, data, resTime) {
//             this.addInput(node, cmd, 'RES', rawData, data, resTime);
//         },
//         addInputResponseTimeout: function (node, cmd) {
//             this.addInput(node, cmd, 'RES_TIMEOUT');
//         },
//         addInputResponseError: function (node, cmd) {
//             this.addInput(node, cmd, 'RES_ERROR');
//         },
//         addInput: function (node, cmd, type, rawData, data, resTime) {
//             inputTime = new Date();
//             if (typeof resTime === 'number') {
//                 resTime = resTime.toLocaleString() + ' ms';
//             }
//             var input = {
//                 Invoke: null,
//                 Event: node + '.' + cmd,
//                 Type: type,
//                 RawData: rawData,
//                 Data: data,
//                 ResTime: resTime
//             };
//             this.Input.push(input);
//         },

//         addOutputRequest: function (node, cmd, rawData, data) {
//             this.addOutput(node, cmd, 'REQ', rawData, data);
//         },
//         addOutputResponse: function (node, cmd, rawData, data) {
//             this.addOutput(node, cmd, 'RES', rawData, data);
//         },
//         addOutputRequestRetry: function (node, cmd, rawData, data, total, maxCount) {
//             this.addOutput(node, cmd, ('REQ_RETRY_' + total + '/' + maxCount), rawData, data);
//         },
//         addOutput: function (node, cmd, type, rawData, data) {
//             outputTime = new Date();
//             var input = {
//                 Invoke: null,
//                 Event: node + '.' + cmd,
//                 Type: type,
//                 RawData: rawData,
//                 Data: data
//             };

//             this.Output.push(input);
//         },

//         end: function () {
//             let currentTime = new Date();
//             detailLog.ProcessingTime = new Date().getTime() - startTimeDate.getTime();
//             detailLog.InputTimeStamp = dateFormat(inputTime, dateFMT);
//             detailLog.OutputTimeStamp = dateFormat(outputTime, dateFMT);;

//             write('dtl', JSON.stringify(detailLog));
//             startTimeDate = currentTime;
//             detailLog._clr();
//         },

//         _clr: function (){
//             detailLog.ProcessingTime = null;
//             detailLog.InputTimeStamp = null;
//             detailLog.OutputTimeStamp= null;
//             detailLog.Input=[];
//             detailLog.Output=[];
//         }
//     }

//     return detailLog;
// }

log.summary = function (session, cmd, identity) {
    var now = new Date();

    var summaryLog = {
        requestTime: now,
        session: session,
        initInvoke: '', //only equinox platform
        cmd: cmd,
        identity: identity,
        /*resultCode: null,
        resultDescription: null,*/
        blockDetail: [],

        addSuccessBlock: function (node, cmd, resultCode, resultDesc) {
            //this.blockDetail.push('['+ node+'; '+cmd+'(1); ['+ resultCode+'; '+resultDesc+'(1)]]');
            addBlock(this.blockDetail, node, cmd, resultCode, resultDesc);
        },

        addErrorBlock: function (node, cmd, resultCode, resultDesc) {
            //this.blockDetail.push('['+ node+'; '+cmd+'(1); ['+ resultCode+'; '+resultDesc+'(1)]]');
            addBlock(this.blockDetail, node, cmd, resultCode, resultDesc);
        },

        end: function (resultCode, resultDescription) {
            var endTime = new Date();

            var blockDetailTxt = '[';
            for (var j = 0; j < this.blockDetail.length; j++) {
                var i = this.blockDetail[j];
                var aa = i.node + '; ' + i.cmd + '(' + i.count + '); [';

                for (var k = 0; k < i.result.length; k++) {
                    var bb = i.result[k].resultCode + '; ' + i.result[k].resultDesc + '(' + i.result[k].count + ')';

                    if (k === i.result.length - 1) {
                        aa += bb;
                    } else {
                        aa += (bb + ', ');
                    }
                }

                if (j === this.blockDetail.length - 1) {
                    aa += ']';
                } else {
                    aa += '], ';
                }
                blockDetailTxt += aa;
            }
            blockDetailTxt += ']';


            var txt = dateFormat(this.requestTime, dateFMT) + '|';
            txt += this.session + '|';
            txt += this.initInvoke + '|'
            txt += this.cmd + '|'
            txt += this.identity + '|'
            txt += resultCode + '|'
            txt += resultDescription + '|'
            txt += blockDetailTxt + '|'
            txt += dateFormat(endTime, dateFMT) + '|'
            txt += (endTime.getTime() - this.requestTime.getTime());

            write('smr', txt);
        }
    };
    return summaryLog;
}

function addBlock(store, node, cmd, resultCode, resultDesc) {
    var found = null;

    for (var i = 0; i < store.length; i++) {
        if (store[i].node === node && store[i].cmd === cmd) {
            found = store[i];
            store[i].count++;
            break;
        }
    }

    if (!found) {
        var result = {
            resultCode: resultCode,
            resultDesc: resultDesc,
            count: 1
        }

        var b = {
            node: node,
            cmd: cmd,
            count: 1,
            result: [result]
        }
        store.push(b);

    } else {
        var foundResult = false;
        for (var j = 0; j < found.result.length; j++) {
            if (found.result[j].resultCode === resultCode &&
                found.result[j].resultDesc === resultDesc) {

                found.result[j].count++;
                foundResult = true;
                break;
            }
        }

        if (!foundResult) {
            var result = {
                resultCode: resultCode,
                resultDesc: resultDesc,
                count: 1
            }
            found.result.push(result);
        }
    }
}

log.init = function (_conf, express) {
    log.initLog = true;
    if (_conf) {
        conf = _conf;
    }
    
    

    if (conf.log) {
        if (conf.log.level === 'debug') {
            conf.log.level = 0;
        } else if (conf.log.level === 'info') {
            conf.log.level = 1;
        } else if (conf.log.level === 'warn') {
            conf.log.level = 2;
        } else if (conf.log.level === 'error') {
            conf.log.level = 3;
        } else {
            conf.log.level = 4;
        }

        //enable only debug
        if (express && conf.log.level === 0) {
            express.use(function (req, res, next) {
                req._reqTimeForLog = Date.now();
                let sid;
                if(typeof log.sessionID === 'function'){
                    sid = log.sessionID(req, res);
                }

                let txtLogReq = 'INCOMING|__Method=' +req.method 
                + ' __URL=' + req.url 
                + ' __Headers=' + JSON.stringify(req.headers?req.headers:"{}" )
                //+ ' __Params=' + JSON.stringify(req.params )
                + ' __Body=' + JSON.stringify(req.body?req.body:"{}");
                
                if(sid){
                    log.debug(sid, txtLogReq);
                }else{
                    log.debug(txtLogReq);
                }     
                
                onHeaders(res, ()=>{
                    let txtLogRes = 'OUTGOING|__Statuscode=' + res.statusCode 
                    + ' __Headers=' + JSON.stringify(res._headers )                
                    + ' __Body=' + req.res.resBody
                    + ' __Restime=' + ( Date.now() - req._reqTimeForLog );
                
                    if(sid){
                        log.debug(sid, txtLogRes);
                    }else{
                        log.debug(txtLogRes);
                    }  
                });
                next();
            });
        }
    }

    initLog();

    if (conf.stat) {
        initDB();
        cron.schedule('*/' + conf.stat.statInterval + ' * * * *', function () {
            fushStat();
        });
    }
    return log;
};

module.exports = log;
// module.exports = commonLog();