File Source for function.keywords.php

<?php
/**
* Zikula Application Framework
*
* @copyright (c) 2004, Zikula Development Team
* @link http://www.zikula.org
* @version $Id: function.keywords.php 24342 2008-06-06 12:03:14Z markwest $
* @license GNU/GPL - http://www.gnu.org/copyleft/gpl.html
* @package Zikula_Template_Plugins
* @subpackage Functions
*/
/**
* Smarty function to get the meta keywords
*
* This function will take the contents of the page and transfer it
* into a keyword list. If stopwords are defined, they are filtered out.
* The keywords are sorted by count.
* As a default, the whole page contents are taken as a base for keyword
* generation. If set, the contents of "contents" are taken.
* Beware that the function always returns the site keywords if "generate
* meta keywords" is turned off.
* PLEASE NOTE: This function adds additional overhead when dynamic keyword
* generation is turned on. You should use Xanthia page caching in this case.
*
* available parameters:
* - contents if set, this wil be taken as a base for the keywords
* - dynamic if set, the keywords will be created from the content / mainconent
* oterwise we use the page vars. The rules are:
* 1) If dynamic keywords disabled in admin settings then use static keywords
* 2) if parameter "dynamic" not set or empty then always use main content (default),
* 3) if parameter "dynamic" set and not empty then use page vars if any set - otherwise use content.
* - assign if set, the keywords will be assigned to this variable
*
* Example
* <meta name="KEYWORDS" content="">
*
* @author Jörg Napp
* @since 03. Feb. 04
* @param array $params All attributes passed to this function from the template
* @param object $smarty Reference to the Smarty object
* @return string the keywords
*/
function smarty_function_keywords($params, &$smarty)
{
if (pnConfigGetVar('dyn_keywords') == 1) {
$keywordsarray = PageUtil::getVar('keywords');
// Check for empty keywords array
$emptyPageVar = (empty($keywordsarray));
if (!isset($params['dynamic']) || empty($params['dynamic']) || $emptyPageVar) {
if (isset($params['contents'])) {
$pagecontent = $params['contents'];
} else if (isset($smarty->_tpl_vars['maincontent'])) {
$pagecontent = $smarty->_tpl_vars['maincontent'];
} else {
return false;
}
// get the contents of the page.
$pagecontent = strtolower(strip_tags(html_entity_decode($pagecontent)));
// strip the contents to an array at each non-letter
// this might be an issue for languages with other charsets.
$keywords = preg_split ('/\W/', $pagecontent);
// sort the array by the most used keys first
$keywords = array_count_values($keywords);
arsort($keywords);
// Remove entry that counts the number of blanks
unset ($keywords['']);
// get back the keywords from the indexes
$keywords = array_keys($keywords);
// remove stopwords
// not correct here: The _user language_ is not relevant, only
// the language of the document. How to get this?
$stopword_file = dirname(__FILE__) . '/stopwords/' . pnUserGetLang() . '.txt';
if (file_exists($stopword_file)) {
$stopwords = file($stopword_file);
$stopwords = array_map('rtrim', $stopwords);
$keywords = array_diff($keywords, $stopwords);
}
// make it a comma-separated string
$keywords = implode(',', $keywords);
} else {
// use PageUtil vars instead, no need to take care about stopwords
$ak = array_keys($keywordsarray); // einmal AK, immer AK ;-)
foreach($ak as $v) {
$keywordsarray[$v] = trim($keywordsarray[$v]);
if (empty($keywordsarray[$v])) {
unset($keywordsarray[$v]);
}
}
$keywords = implode(',', $keywordsarray);
}
} else {
$keywords = pnConfigGetVar('metakeywords');
}
if (isset($params['assign'])) {
$smarty->assign($params['assign'], $keywords);
} else {
return $keywords;
}
}
if (!function_exists('html_entity_decode')) {
/**
* html_entity_decode()
*
* Convert all HTML entities to their applicable characters
* This function is a fallback if html_entity_decode isn't defined
* in the PHP version used (i.e. PHP < 4.3.0).
* Please note that this function doesn't support all parameters
* of the original html_entity_decode function.
*
* @param string $string the this function converts all HTML entities to their applicable characters from string.
* @return the converted string
* @link http://php.net/html_entity_decode The documentation of html_entity_decode
***/
function html_entity_decode($string)
{
$trans_tbl = get_html_translation_table(HTML_ENTITIES);
$trans_tbl = array_flip($trans_tbl);
return (strtr($string, $trans_tbl));
}
}

Source for file function.keywords.php