Highlight search engine keywords for the landing page

hl.js

/**
* 关键词高亮动态解析
*
* @author Saturn
* @since  1.0.0
* @return void
*/
var Highlighter={
	highlight:
		function(b,a){
			b=b.replace(/(^\s*)|(\s*$)/g,"");
			if(!b||b.length==0){
				return;
			}
			var c=new RegExp("("+b.split(/\s+/).join("(?!;)|")+"(?!;))","ig");

			if("undefined"==typeof(a)){return;}
			for(i in a){
				if(a[i].innerHTML){a[i].innerHTML=a[i].innerHTML.replace(c,'<span style="color:#c00;font-size:1em;font-weight:inherit">$1</span>');}
			}
		}
};

hl.php

/**
 * search_engine_hl
 *
 * 提取来自搜索引擎的关键词
 * 
 * 
 * 目前支持的搜索引擎包括: Google/Baidu/Yahoo/游子站内搜索
 *
 * @return 	mixed 
 */
function search_engine_hl()
{	
	$ref = ( ! isset($_SERVER['HTTP_REFERER']) OR $_SERVER['HTTP_REFERER'] == '') 
		? '' 
		: trim($_SERVER['HTTP_REFERER']);
	
	// There is no referer, exit...
	if( $ref == '') return FALSE;
	
	// Parse the referer URL
	parse_str(parse_url($ref , PHP_URL_QUERY) , $query);
	
	// Filter function to prevent potential XSS attacks
	$filter = function($match) {
		return trim(strip_tags($match));
	};
	
	// Referer from Google, Yahoo and our own search engine...
	foreach(array('q', 'p', 'query') as $key)
	{
		if(isset($query[$key]) AND $query[$key])
		{
			return $filter($query[$key]);
		}
	}
	
	// Referer from Baidu, extra works should be done
	if(isset($query['wd']) AND $query['wd'])
	{
		return $filter(iconv('gb2312', 'utf-8', urldecode($query['wd'])));
	}
	
	return FALSE;
}