/**
 *	File: app/helper.js
 *	Author: Gerrit Linnemann
 *	
 *	Swiss-knife.
 */


// load the things we need
var logger    = require('./logging')
,   jsonlint  = require("jsonlint");


exports.init = function(express) {

	return this;
}

exports.timeSince = function(date) {

    var seconds = Math.floor((new Date() - date) / 1000);

    var interval = Math.floor(seconds / 31536000);

    if (interval > 1) {
        return interval + " years";
    }
    interval = Math.floor(seconds / 2592000);
    if (interval > 1) {
        return interval + " months";
    }
    interval = Math.floor(seconds / 86400);
    if (interval > 1) {
        return interval + " days";
    }
    interval = Math.floor(seconds / 3600);
    if (interval > 1) {
        return interval + " hours";
    }
    interval = Math.floor(seconds / 60);
    if (interval > 1) {
        return interval + " minutes";
    }
    return Math.floor(seconds) + " seconds";
}

exports.isOlderThanXMinutes = function(date, minutes) {
  var seconds = Math.floor((new Date() - date) / 1000)
  interval = seconds / 60
  
  return interval > minutes
}

exports.dayOfYear = function() {
  var now = new Date();
  var start = new Date(now.getFullYear(), 0, 0);
  var diff = now - start;
  var oneDay = 1000 * 60 * 60 * 24;
  var day = Math.floor(diff / oneDay);

  logger.trace('Helper | day of year: ' + day);
  return day;
}

exports.isJSON = function(jsonString) {
  try {
    return jsonlint.parse(jsonString)
  } catch (e) {
    if(logger.isDebug()) {
      logger.error(e.message)
      //logger.inspect('Error checking JSON', e)
    }
  }

  return false;
}

exports.isArray = function(toCheck) {
  return (Object.prototype.toString.call( toCheck ) === '[object Array]');
}

exports.isDefinedAndNotNull = function(toCheck) {
	return (
		typeof toCheck !== 'undefined' &&
		toCheck != null
	);
}

exports.getRandomInt = function(min, max) {
    min = Math.ceil(min);
    max = Math.floor(max);
    return Math.floor(Math.random() * (max - min + 1)) + min;
}

exports.bytesToSize = function(bytes, precision){
  var kilobyte = 1024;
  var megabyte = kilobyte * 1024;
  var gigabyte = megabyte * 1024;
  var terabyte = gigabyte * 1024;
 
  if ((bytes >= 0) && (bytes < kilobyte)) {
    return bytes + ' B';

  } else if ((bytes >= kilobyte) && (bytes < megabyte)) {
    return (bytes / kilobyte).toFixed(precision) + ' KB';

  } else if ((bytes >= megabyte) && (bytes < gigabyte)) {
    return (bytes / megabyte).toFixed(precision) + ' MB';

  } else if ((bytes >= gigabyte) && (bytes < terabyte)) {
    return (bytes / gigabyte).toFixed(precision) + ' GB';

  } else if (bytes >= terabyte) {
    return (bytes / terabyte).toFixed(precision) + ' TB';

  } else {
    return bytes + ' B';
  }
}

/* private */
function bytesToGB(bytes, precision) {
  var kilobyte = 1024;
  var megabyte = kilobyte * 1024;
  var gigabyte = megabyte * 1024;
  var terabyte = gigabyte * 1024;

  return (bytes / gigabyte).toFixed(precision);
}

/* private */
function bytesToMB(bytes, precision) {
  var kilobyte = 1024;
  var megabyte = kilobyte * 1024;
  var gigabyte = megabyte * 1024;
  var terabyte = gigabyte * 1024;

 return (bytes / megabyte).toFixed(precision);
}