[php-blog-cvs] serendipity/plugins/serendipity_event_searchhighlight serendipity_event_searchhighlight.php,NONE,1.1

[Tom S. <tom...@us...>]

Update of /cvsroot/php-blog/serendipity/plugins/serendipity_event_searchhighlight
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv6000

Added Files:
	serendipity_event_searchhighlight.php 
Log Message:
Add Search Engine Highlight plugin. 
It will highlight the words used in a search engine to locate your blog.


--- NEW FILE: serendipity_event_searchhighlight.php ---
<?php # $Id: serendipity_event_searchhighlight.php,v 1.1 2004/08/25 16:29:47 tomsommer Exp $

/**********************************/
/*  Authored by Tom Sommer, 2004  */
/**********************************/

switch ($serendipity['lang']) {
    case 'en':
    default:
        @define('PLUGIN_EVENT_SEARCHHIGHLIGHT_NAME',     'Highlight search queries');
        @define('PLUGIN_EVENT_SEARCHHIGHLIGHT_DESC',     'Highlights queries used to locate your page in a search engine');
        break;
}

class serendipity_event_searchhighlight extends serendipity_event
{
    function introspect(&$propbag)
    {
        global $serendipity;

        $propbag->add('name',          PLUGIN_EVENT_SEARCHHIGHLIGHT_NAME);
        $propbag->add('description',   PLUGIN_EVENT_SEARCHHIGHLIGHT_DESC);
        $propbag->add('event_hooks', array('frontend_display' => true, 'css' => true));

        $this->markup_elements = array(
            array(
              'name'     => ENTRY_BODY,
              'element'  => 'body',
            ),
            array(
              'name'     => EXTENDED_BODY,
              'element'  => 'extended',
            ),
            array(
              'name'     => COMMENT,
              'element'  => 'comment',
            ),
            array(
              'name'     => HTML_NUGGET,
              'element'  => 'html_nugget',
            )
        );

        $conf_array = array();
        foreach($this->markup_elements as $element) {
            $conf_array[] = $element['name'];
        }
        $propbag->add('configuration', $conf_array);
    }


    function generate_content(&$title) {
        $title = PLUGIN_EVENT_SEARCHHIGHLIGHT_NAME;
    }


    function introspect_config_item($name, &$propbag)
    {
        $propbag->add('type',        'boolean');
        $propbag->add('name',        $name);
        $propbag->add('description', sprintf(APPLY_MARKUP_TO, $name));
        $propbag->add('default', 'true');
        return true;
    }

    function loadConstants() {
        define('PLUGIN_EVENT_SEARCHHIGHLIGHT_NONE', 0);
        define('PLUGIN_EVENT_SEARCHHIGHLIGHT_GOOGLE', 1);
        define('PLUGIN_EVENT_SEARCHHIGHLIGHT_YAHOO', 2);
        define('PLUGIN_EVENT_SEARCHHIGHLIGHT_LYCOS', 3);
        define('PLUGIN_EVENT_SEARCHHIGHLIGHT_MSN', 4);
        define('PLUGIN_EVENT_SEARCHHIGHLIGHT_ALTAVISTA', 5);
    }

    function getSearchEngine() {
        $url = parse_url($this->uri);

        /* Patterns should be placed in the order in which they are most likely to occur */
        if ( preg_match('@^(www\.)?google\.@i', $url['host']) ) {
            return PLUGIN_EVENT_SEARCHHIGHLIGHT_GOOGLE;
        }
        if ( preg_match('@^search\.yahoo\.@i', $url['host']) ) {
            return PLUGIN_EVENT_SEARCHHIGHLIGHT_YAHOO;
        }
        if ( preg_match('@^search\.lycos\.@i', $url['host']) ) {
            return PLUGIN_EVENT_SEARCHHIGHLIGHT_LYCOS;
        }
        if ( preg_match('@^search\.msn\.@i', $url['host']) ) {
            return PLUGIN_EVENT_SEARCHHIGHLIGHT_MSN;
        }
        if ( preg_match('@^(www\.)?altavista\.@i', $url['host']) ) {
            return PLUGIN_EVENT_SEARCHHIGHLIGHT_ALTAVISTA;
        }


        return false;
    }

    function getQuery() {
        if ( empty($this->uri) ) {
            return false;
        }

        $this->loadConstants();
        $url = parse_url($this->uri);
        parse_str($url['query'], $pStr);

        switch ( $this->getSearchEngine() ) {
            case PLUGIN_EVENT_SEARCHHIGHLIGHT_GOOGLE :
                $query = $pStr['q'];
                break;

            case PLUGIN_EVENT_SEARCHHIGHLIGHT_YAHOO :
                $query = $pStr['p'];
                break;

            case PLUGIN_EVENT_SEARCHHIGHLIGHT_LYCOS :
                $query = $pStr['query'];
                break;

            case PLUGIN_EVENT_SEARCHHIGHLIGHT_MSN :
                $query = $pStr['q'];
                break;

            case PLUGIN_EVENT_SEARCHHIGHLIGHT_ALTAVISTA :
                $query = $pStr['q'];
                break;

            default:
                return false;
        }

        /* Clean the query */
        $query = trim($query);
        $query = preg_replace('/(\"|\')/i', '', $query);

        /* Split by search engine chars or spaces */
        $words = preg_split('/[\s\,\+\.\-\/\=]+/', $query);

        /* Strip search engine keywords or common words we don't bother to highlight */
        $words = array_diff($words, array('AND', 'OR', 'FROM', 'IN'));

        return $words;
    }


    function event_hook($event, &$bag, &$eventData) {
        global $serendipity;

        $this->uri = $_SERVER['HTTP_REFERER'];
        $hooks = &$bag->get('event_hooks');
        
        if (!isset($hooks[$event])) {
            return false;
        }
        
        if ( $event == 'frontend_display' ) {
            if ( ($queries = $this->getQuery()) === false ) {
                return;
            }

            foreach ($this->markup_elements as $temp) {
                if ( ! (serendipity_db_bool($this->get_config($temp['name'], true)) && isset($eventData[$temp['element']])) ) {
                    continue;
                }
                
                $element = &$eventData[$temp['element']];
                      
                foreach ( $queries as $word ) {
                    /* If the data contains HTML tags, we have to be careful not to break URIs and use a more complex preg */
                    if ( preg_match('/\<.+\>/', $element) ) {
                        $_pattern =  '/(?!<.*?)(\b'. preg_quote($word, '/') .'\b)(?![^<>]*?>)/im';
                    } else {
                        $_pattern = '/(\b'. preg_quote($word, '/') .'\b)/im';
                    }
                    $element = preg_replace($_pattern, '<span class="serendipity_searchQuery">$1</span>', $element);
                } // end foreach
            } // end foreach
            return;
        } // end if


        if ( $event == 'css' ) {
            /* If the user hasn't added a CSS Class called serendipity_searchQuery, we add a pretty one for him */
            if ( strstr($eventData, '.serendipity_searchQuery') === false ) {
                $eventData .= "\n";
                $eventData .= '.serendipity_searchQuery {' . "\n";
                $eventData .= '    background-color: #D81F2A;' . "\n";
                $eventData .= '    color: #FFFFFF;' . "\n";
                $eventData .= '}' . "\n";
            }
            return;
        }

    } // end function
}

/* vim: set sts=4 ts=4 expandtab : */
?>