Auto Text Color Detector

text-color-detector.js

// Converts color code to RGB
//====================================
function colorCodeToRGB(colorCode){
    var c;
    var rgbaValidation = (/([R][G][B][A]?[(]\s*([01]?[0-9]?[0-9]|2[0-4][0-9]|25[0-5])\s*,\s*([01]?[0-9]?[0-9]|2[0-4][0-9]|25[0-5])\s*,\s*([01]?[0-9]?[0-9]|2[0-4][0-9]|25[0-5])(\s*,\s*((0\.[0-9]{1})|(1\.0)|(1)))?[)])/i.test(colorCode)) ;
    
    var hexValidation = (/^#([A-Fa-f0-9]{3}){1,2}$/.test(colorCode));
    
    if(hexValidation){
        c= colorCode.substring(1).split('');
        if(c.length== 3){
            c= [c[0], c[0], c[1], c[1], c[2], c[2]];
        }
        c= '0x'+c.join('');
        return 'rgb('+[(c>>16)&255, (c>>8)&255, c&255].join(',')+')';
      
    }else if(rgbaValidation){
      
      return colorCode;
    }
    return colorCode;
}


// Detects text color based on given color
//=====================================
function autoTextColor(bgColor, lightColor, darkColor){
  var lightTextColor = (typeof lightColor === "string")? lightColor : "#fff";
  var darkTextColor = (typeof darkColor === "string")? darkColor : "#333";
  var rgbString = colorCodeToRGB(bgColor);
  
  var matchColors = /rgb\((\d{1,3})\s*,\s*(\d{1,3})\s*,\s*(\d{1,3})\)/;
  var rgb = matchColors.exec(rgbString);

  if (rgb === null) {
      return;
  }

  var o = Math.round(((parseInt(rgb[1]) * 299) +
                      (parseInt(rgb[2]) * 587) +
                      (parseInt(rgb[3]) * 114)) / 1000);
  
  return (o > 125) ? darkTextColor : lightTextColor;
}