/********************************************************************
* UTILS
*********************************************************************/
// https://stackoverflow.com/q/779379
setTimeout(function (callback) {
  // Offload Heavy computation. 
}, 0);

/********************************************************************
* JQUERY serializeArray
*********************************************************************/

// Converts form into Array of Objects.
// https://plainjs.com/javascript/ajax/serialize-form-data-into-an-array-46/
function serializeArray(form) {
  var field, l, s = [];
  if (typeof form == 'object' && form.nodeName == "FORM") {
    var len = form.elements.length;
    for (var i = 0; i < len; i++) {
      field = form.elements[i];
      if (field.name && !field.disabled && field.type != 'file' && field.type != 'reset' && field.type != 'submit' && field.type != 'button') {
        if (field.type == 'select-multiple') {
          l = form.elements[i].options.length;
          for (j = 0; j < l; j++) {
            if (field.options[j].selected)
              s[s.length] = {
                name: field.name,
                value: field.options[j].value
              };
          }
        } else if ((field.type != 'checkbox' && field.type != 'radio') || field.checked) {
          s[s.length] = {
            name: field.name,
            value: field.value
          };
        }
      }
    }
  }
  return s;
}


// Nodejs check if module is called directly
const CALLED_DIRECTLY = require.main === module;

function splitTextarea(text) {
  return text.trim().replace(/\s+/, '\n').replace(/\n{2,}/, '').split('\n');
}

// Download using fetch API..
import download from 'downloadjs';
const handleBufferDownload = (filename) => {
  res.arrayBuffer()
    .then((buffer) => {
      download(buffer, filename, contentType);
      stopLoading();
    });
};

// http://stackoverflow.com/a/23842171
encodeURIComparison = function() {
  var arr = [];
  for(var i=0; i<256; i++) {
    var char=String.fromCharCode(i);
    if(encodeURI(char) !== encodeURIComponent(char)) {
      arr.push({
        character: char,
        encodeURI: encodeURI(char),
        encodeURIComponent: encodeURIComponent(char)
      });
    }
  }
  console.table(arr);  
};

function encodeQueryParams (url, queryParams) {
  return Object.keys(queryParams).reduce((a, key) => {
    a.push(key + '=' + encodeURIComponent(queryParams[key]));
    return a;
  }, []).join('&');
}

let queryString = encodeQueryParams(queryParams);
url += url.indexOf('?') > -1 ? '&' : '?' + queryString;

/********************************************************************
* JQUERY COLOR CONTRAST 
*********************************************************************/
jQuery.Color.fn.contrastColor = function() {
    var r = this._rgba[0], g = this._rgba[1], b = this._rgba[2];
    return (((r*299)+(g*587)+(b*144))/1000) >= 131.5 ? "black" : "white";
};

// usage examples:
jQuery.Color("#bada55").contrastColor(); // "black"
element.css( "color", jQuery.Color( element, "backgroundColor" ).contrastColor() );