Matt.
Version: 1.5
Author: Ryan Boren
Author URI: http://boren.nu
*/
function get_search_query_terms($engine = 'google') {
$referer = urldecode($_SERVER['HTTP_REFERER']);
$query_array = array();
switch ($engine) {
case 'google':
// Google query parsing code adapted from Dean Allen's
// Google Hilite 0.3. http://textism.com
$query_terms = preg_replace('/^.*q=([^&]+)&?.*$/i','$1', $referer);
$query_terms = preg_replace('/\'|"/', '', $query_terms);
$query_array = preg_split ("/[\s,\+\.]+/", $query_terms);
break;
case 'lycos':
$query_terms = preg_replace('/^.*query=([^&]+)&?.*$/i','$1', $referer);
$query_terms = preg_replace('/\'|"/', '', $query_terms);
$query_array = preg_split ("/[\s,\+\.]+/", $query_terms);
break;
case 'yahoo':
$query_terms = preg_replace('/^.*p=([^&]+)&?.*$/i','$1', $referer);
$query_terms = preg_replace('/\'|"/', '', $query_terms);
$query_array = preg_split ("/[\s,\+\.]+/", $query_terms);
break;
case 'wordpress':
$search = get_query_var('s');
$search_terms = get_query_var('search_terms');
if (!empty($search_terms)) {
$query_array = $search_terms;
} else if (!empty($search)) {
$query_array = array($search);
} else {
$query_terms = preg_replace('/^.*s=([^&]+)&?.*$/i','$1', $referer);
$query_terms = preg_replace('/\'|"/', '', $query_terms);
$query_array = preg_split ("/[\s,\+\.]+/", $query_terms);
}
}
return $query_array;
}
function is_referer_search_engine($engine = 'google') {
if( empty($_SERVER['HTTP_REFERER']) && 'wordpress' != $engine ) {
return false;
}
$referer = urldecode($_SERVER['HTTP_REFERER']);
if ( ! $engine ) {
return false;
}
switch ($engine) {
case 'google':
if (preg_match('|^http://(www)?\.?google.*|i', $referer)) {
return true;
}
break;
case 'lycos':
if (preg_match('|^http://search\.lycos.*|i', $referer)) {
return true;
}
break;
case 'yahoo':
if (preg_match('|^http://search\.yahoo.*|i', $referer)) {
return true;
}
break;
case 'wordpress':
if ( is_search() )
return true;
$siteurl = get_option('home');
if (preg_match("#^$siteurl#i", $referer))
return true;
break;
}
return false;
}
function hilite($text) {
$search_engines = array('wordpress', 'google', 'lycos', 'yahoo');
foreach ($search_engines as $engine) {
if ( is_referer_search_engine($engine)) {
$query_terms = get_search_query_terms($engine);
foreach ($query_terms as $term) {
if (!empty($term) && $term != ' ') {
$term = preg_quote($term, '/');
if (!preg_match('/<.+>/',$text)) {
$text = preg_replace('/(\b'.$term.'\b)/i','$1',$text);
} else {
$text = preg_replace('/(?<=>)([^<]+)?(\b'.$term.'\b)/i','$1$2',$text);
}
}
}
break;
}
}
return $text;
}
function hilite_head() {
echo "
";
}
// Highlight text and comments:
add_filter('the_content', 'hilite');
add_filter('the_excerpt', 'hilite');
add_filter('comment_text', 'hilite');
add_action('wp_head', 'hilite_head');
?>