cronjob

const events = require("events").EventEmitter;


/*
    Added complex matches by Shimon Doodkin 2012
    Developed by Elijah Rutschman 2009 - http://elijahr.blogspot.com/2009/03/javascript-cron.html
*/
/*
a typical cron entry has either wildcards (*) or an integer:

            .---------------- minute (0 - 59) 
            | .-------------- hour (0 - 23)
            | | .------------ day of month (1 - 31)
            | | | .---------- month (1 - 12)
            | | | | .-------- day of week (0 - 6) (Sunday=0)
            | | | | |
            * * * * *
*/
//          m h d M w
//cron.add("* * * * *", function(){console.log('cron job that runs every minute')})

console.log("Started...");


function Cron(options) {

    this.options = Object.assign({
        autostart: true
    }, options);

    this.jobs = [];
    this.interval = null;

    if (this.options.autostart) {
        process.nextTick(() => {
            this.start();
        });
    }

};

Cron.prototype.add = function (str, cb) {

    let job = {};

    let items = str.match(/^([0-9,\-\/]+|\*{1}|\*{1}\/[0-9]+)\s+([0-9,\-\/]+|\*{1}|\*{1}\/[0-9]+)\s+([0-9,\-\/]+|\*{1}|\*{1}\/[0-9]+)\s+([0-9,\-\/]+|\*{1}|\*{1}\/[0-9]+)\s+([0-9,\-\/]+|\*{1}|\*{1}\/[0-9]+)\s*$/);

    job.minute = this._parse(items[1]);
    job.hour = this._parse(items[2]);
    job.date = this._parse(items[3]);
    job.month = this._parse(items[4]);
    job.day = this._parse(items[5]);

    job.cb = cb;
    this.jobs.push(job);

};


Cron.prototype.stop = function () {
    clearInterval(this.interval);
}

Cron.prototype.start = function () {

    this.stop();

    this.interval = setInterval(() => {
        this._process();
    }, 1000); //600000

}

Cron.prototype._match = function (a, b) {
    for (var c, b0, i = 0; i < a.length; i++) {
        c = a[i];
        if (c[0] === -1 || (b >= c[0] && b <= c[1])) {
            b0 = b - c[0]; // make the modulo start from 1st miniture of from matched time, not first minute of from 0 minutes
            if (c[2] === -1 || b0 === 0 || b0 % c[2] === 0)
                return true;
        }
    }
    return false;
};

Cron.prototype._parse = function (v) {
    return v.split(',').map((i) => {

        let z = i.split('/');
        let x = z[0].split('-');

        if (x[0] == "*") {
            x[0] = -1;
        }

        if (x.length == 1) {
            x.push(x[0]);
        }

        x[2] = z.length === 1 ? -1 : z[1];
        // parsed array structure:
        x[0] = parseInt(x[0]);// 0 - from
        x[1] = parseInt(x[1]);// 1 - to
        x[2] = parseInt(x[2]);// 2 modulus 

        return x;

    });
};

Cron.prototype._process = function () {

    let now = new Date();

    for (let i = 0; i < this.jobs.length; i++) {
        if (this._match(this.jobs[i].minute, now.getMinutes())) {
            if (this._match(this.jobs[i].hour, now.getHours())) {
                if (this._match(this.jobs[i].date, now.getDate())) {
                    if (this._match(this.jobs[i].month, now.getMonth())) {
                        if (this._match(this.jobs[i].day, now.getDay())) {

                            this.jobs[i].cb();

                        }
                    }
                }
            }
        }
    }

};




const cron = new Cron();

// when cron is not running:
// queue up some jobs to run
cron.add("* * * * *", function () { console.log(Date.now(), 'cron job 0 just ran') })
cron.add("*/6 * * * *", function () { console.log(Date.now(), 'cron job 1 just ran') })
cron.add("05 * * * *", function () { console.log(Date.now(), 'cron job 2 just ran') })
cron.add("15 * * * *", function () { console.log(Date.now(), 'cron job 3 just ran') })
cron.add("30 * * * *", function () { console.log(Date.now(), 'cron job 4 just ran') })
cron.add("45 * * * *", function () { console.log(Date.now(), 'cron job 8 just ran') })
cron.add("50 * * * *", function () { console.log(Date.now(), 'cron job 9 just ran') })

cron.start();

// Cron already running, but we can add more jobs, no problem
cron.add("0 * * * *", function () { console.log(Date.now(), 'cron job 5 just ran') })
cron.add("20 9 * * 1,2,3,4,5", function () { console.log(Date.now(), 'at 9:07 of every morning from sunday to thursday') })


//testing the rulls matching:
var x;
console.log(x = cron._parse("5,10,15,20,25,30,35,40,45,50,55")) // ruls can be 1-2/3,3-4/5  many match options are seperated by comma. but no spacing in between
console.log(cron._match(x, 15));


  /// each place can be : [number or number-number or *]/[modulus],[number or number-number or *]/[modulus],...
  //       *  any number
  //       5  number is 5
  //    2-10  number from 5 to 10
  //     */3  every 3rd will run, - optionaly after the / comes modulus, modulus calulates reminder, if reminder is zero means it devides by that number exactly
  //  2-10/3  between 5 to 10 every 3rd will run
  //  
  //  2-10,12-16  many matchs but no spacing in between
  //  2-10/5,12-16/2,*/10  alot matchs example