This module helps you classify days in fixed days cycles.

Suppose you work three days and rest two, there is a cycle of five days, to know if you work today do something as:

var dma = require('dma');

// set initial date and the number of days on each cycle.
var cycle = dma('2015-05-14', 5);

function doWork (date) {
  return [0,1,2].indexOf(cycle(date)) !== -1;
}

console.log(doWork('2015-06-20')); // => true
console.log(doWork('2015-06-21')); // => false

Time zones

In node dates are always UTC, but in the browser it will depend on the locale of the client, so it is better to specify the full date in the initial field like: var cycle = dma('2015-05-14T00:00-0300', 5);. Then you can query with cycle() to get the actual (on the client locale time) congruence class.

License

Copyright (C) 2015 Eloy Espinaco

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.