$.fn.addHighlight = function(targetText, targetOperator = '='){
  function _addHighlight(targetNode, targetText, targetOperator = '='){
    var addNodeLength = 0;
    if(targetNode.nodeType == 3){
      switch(true){
        case /^=$/.test(targetOperator):
          var targetRegex = targetText.replace(/[-\/\\^$*+?.()|\[\]{}]/g, '\\$&');
          var replaceText = targetNode.textContent.replace(new RegExp('(' + targetRegex + ')', 'g'), '<span class="highlight">$1</span>');
          if(replaceText != targetNode.textContent){
            $(targetNode).replaceWith(replaceText);
            addNodeLength = 2;
          }
          break;
        case /^ILIKE$/i.test(targetOperator):
          var targetRegex = targetText.replace(/[-\/\\^$*+?.()|\[\]{}]/g, '\\$&').replace(/%/g, '.*').replace(/\\\\\.\*/g, '%').replace(/_/g, '.').replace(/\\\\\./g, '_');
          var replaceText = targetNode.textContent.replace(new RegExp('(' + targetRegex + ')', 'gi'), '<span class="highlight">$1</span>');
          if(replaceText != targetNode.textContent){
            $(targetNode).replaceWith(replaceText);
            addNodeLength = 2;
          }
          break;
        case /^[$%a]{2}[-:][$%b]{2}[-:][$%c]{2}$/.test(targetOperator):
          var targetParts = targetNode.textContent.match(/(\d+)/g);
          var targetRegex = targetOperator.replace(/\$a/, targetParts[0]).replace(/\$b/, targetParts[1]).replace(/\$c/, targetParts[2]).replace(/%%/, '\\d+');
          var replaceText = targetNode.textContent.replace(new RegExp('(' + targetRegex + ')', 'gi'), '<span class="highlight">$1</span>');
          if(replaceText != targetNode.textContent){
            $(targetNode).replaceWith(replaceText);
            addNodeLength = 2;
          }
          break;
        case /^[<>]=?$/.test(targetOperator):
          var targetValue = targetNode.textContent.trim();
          var replaceText;
          switch(targetOperator){
            case '<':
              if(targetValue < targetText) replaceText = targetNode.textContent.replace(new RegExp('(' + targetValue + ')', 'gi'), '<span class="highlight">$1</span>');
              break;
            case '>':
              if(targetValue > targetText) replaceText = targetNode.textContent.replace(new RegExp('(' + targetValue + ')', 'gi'), '<span class="highlight">$1</span>');
              break;
            case '<=':
              if(targetValue <= targetText) replaceText = targetNode.textContent.replace(new RegExp('(' + targetValue + ')', 'gi'), '<span class="highlight">$1</span>');
              break;
            case '>=':
              if(targetValue >= targetText) replaceText = targetNode.textContent.replace(new RegExp('(' + targetValue + ')', 'gi'), '<span class="highlight">$1</span>');
              break;
          }
          if(replaceText != targetNode.textContent){
            $(targetNode).replaceWith(replaceText);
            addNodeLength = 2;
          }
          break;
      }
    }
    else if(targetNode.nodeType == 1 && targetNode.childNodes && !/(script|style)/i.test(targetNode.tagName)){
      for(var i = 0; i < targetNode.childNodes.length; i++){
        i += _addHighlight(targetNode.childNodes[i], targetText, targetOperator);
      }
    }

    return addNodeLength;
  }

  return this.length && targetText && targetText.length ? this.each(function(){
    _addHighlight(this, targetText, targetOperator);
  }) : this;
}

$.fn.removeHighlight = function(){
  return this.find('span.highlight').each(function(){
    $(this).contents().unwrap();
  }).end();
};