rewrite.php Nextgen Gallery

<?php

/**
* nggRewrite - Rewrite Rules for NextGEN Gallery
*
* sorry wp-guys I didn't understand this at all.
* I tried it a couple of hours : this is the only pooooor result
*
* @package NextGEN Gallery
* @author Alex Rabe
* @copyright 2008-2011
*/
class nggRewrite {

    /**
     * Default slug name
     *
     * @since 1.8.0
     * @var string
     */
    var $slug = 'nggallery';

    /**
     * Contain the main rewrite structure
     *
     * @since 1.8.3
     * @var array
     */
    var $ngg_rules = '';

    /**
    * Constructor
    */
    function nggRewrite() {

        // read the option setting
        $this->options = get_option('ngg_options');

        // get later from the options
        $this->slug = $this->options['permalinkSlug'];

        /*WARNING: Do nothook rewrite rule regentation on the init hook for anything other than dev. */
        //add_action('init',array(&$this, 'flush'));

        add_filter('query_vars', array(&$this, 'add_queryvars') );
        add_filter('wp_title' , array(&$this, 'rewrite_title') );

        //DD32 recommend : http://groups.google.com/group/wp-hackers/browse_thread/thread/50ac0d07e30765e9
        //add_filter('rewrite_rules_array', array($this, 'RewriteRules'));

        if ($this->options['usePermalinks'])
            add_action('generate_rewrite_rules', array(&$this, 'RewriteRules'));

        // setup the main rewrite structure for the plugin
        $this->ngg_rules = array(
            '/page-([0-9]+)/' => '&nggpage=[matches]',
            '/image/([^/]+)/' => '&pid=[matches]',
            '/image/([^/]+)/page-([0-9]+)/' => '&pid=[matches]&nggpage=[matches]',
            '/slideshow/' => '&show=slide',
            '/images/' => '&show=gallery',
            '/tags/([^/]+)/' => '&gallerytag=[matches]',
            '/tags/([^/]+)/page-([0-9]+)/' => '&gallerytag=[matches]&nggpage=[matches]',
            '/([^/]+)/' => '&album=[matches]',
            '/([^/]+)/page-([0-9]+)/' => '&album=[matches]&nggpage=[matches]',
            '/([^/]+)/([^/]+)/' => '&album=[matches]&gallery=[matches]',
            '/([^/]+)/([^/]+)/slideshow/' => '&album=[matches]&gallery=[matches]&show=slide',
            '/([^/]+)/([^/]+)/images/' => '&album=[matches]&gallery=[matches]&show=gallery',
            '/([^/]+)/([^/]+)/page-([0-9]+)/' => '&album=[matches]&gallery=[matches]&nggpage=[matches]',
            '/([^/]+)/([^/]+)/page-([0-9]+)/slideshow/' => '&album=[matches]&gallery=[matches]&nggpage=[matches]&show=slide',
            '/([^/]+)/([^/]+)/page-([0-9]+)/images/' => '&album=[matches]&gallery=[matches]&nggpage=[matches]&show=gallery',
            '/([^/]+)/([^/]+)/image/([^/]+)/' => '&album=[matches]&gallery=[matches]&pid=[matches]'
        );


    } // end of initialization

    /**
    * Get the permalink to a picture/album/gallery given its ID/name/...
    */
    function get_permalink( $args ) {
        global $wp_rewrite, $wp_query;

        // taken from is_frontpage plugin, required for static homepage
        $show_on_front = get_option('show_on_front');
        $page_on_front = get_option('page_on_front');

        //TODO: Watch out for ticket http://trac.wordpress.org/ticket/6627
        if ($wp_rewrite->using_permalinks() && $this->options['usePermalinks'] ) {
            $post = &get_post(get_the_ID());

            // If the album is not set before get it from the wp_query ($_GET)
            if ( !isset ($args['album'] ) )
                $album = get_query_var('album');
            if ( !empty( $album ) )
                $args ['album'] = $album;

            $gallery = get_query_var('gallery');
            if ( !empty( $gallery ) )
                $args ['gallery'] = $gallery;

            $gallerytag = get_query_var('gallerytag');
            if ( !empty( $gallerytag ) )
                $args ['gallerytag'] = $gallerytag;

            /** urlconstructor =  post url | slug | tags | [nav] | [show]
                tags :  album, gallery  -> /album-([0-9]+)/gallery-([0-9]+)/
                        pid             -> /image/([0-9]+)/
                        gallerytag      -> /tags/([^/]+)/
                nav  :  nggpage         -> /page-([0-9]+)/
                show :  show=slide      -> /slideshow/
                        show=gallery    -> /images/
            **/

            // 1. Post / Page url + main slug
            $url = trailingslashit ( get_permalink ($post->ID) ) . $this->slug;
            //TODO: For static home pages generate the link to the selected page, still doesn't work
            if (($show_on_front == 'page') && ($page_on_front == get_the_ID()))
                $url = trailingslashit ( $post->guid ) . $this->slug;

            // 2. Album, pid or tags
            if (isset ($args['album']) && ($args['gallery'] == false) )
                $url .= '/' . $args['album'];
            elseif  (isset ($args['album']) && isset ($args['gallery']) )
                $url .= '/' . $args['album'] . '/' . $args['gallery'];

            if  (isset ($args['gallerytag']))
                $url .= '/tags/' . $args['gallerytag'];

            if  (isset ($args['pid']))
                $url .= '/image/' . $args['pid'];

            // 3. Navigation
            if  (isset ($args['nggpage']) && ($args['nggpage']) )
                $url .= '/page-' . $args['nggpage'];
            elseif (isset ($args['nggpage']) && ($args['nggpage'] === false) && ( count($args) == 1 ) )
                $url = trailingslashit ( get_permalink ($post->ID) ); // special case instead of showing page-1, we show the clean url

            // 4. Show images or Slideshow
            if  (isset ($args['show']))
                $url .= ( $args['show'] == 'slide' ) ? '/slideshow' : '/images';

            return apply_filters('ngg_get_permalink', $url, $args);

        } else {
            // we need to add the page/post id at the start_page otherwise we don't know which gallery is clicked
            if (is_home())
                $args['pageid'] = get_the_ID();

            if (($show_on_front == 'page') && ($page_on_front == get_the_ID()))
                $args['page_id'] = get_the_ID();

            if ( !is_singular() )
                $query = htmlspecialchars( add_query_arg($args, get_permalink( get_the_ID() )) );
            else
                $query = htmlspecialchars( add_query_arg( $args ) );

            return apply_filters('ngg_get_permalink', $query, $args);
        }
    }

    /**
    * The permalinks needs to be flushed after activation
    */
    function flush() {
        global $wp_rewrite, $ngg;

        // reload slug, maybe it changed during the flush routine
        $this->slug = $ngg->options['permalinkSlug'];

        if ($ngg->options['usePermalinks'])
            add_action('generate_rewrite_rules', array(&$this, 'RewriteRules'));

        $wp_rewrite->flush_rules();
    }

    /**
    * add some more vars to the big wp_query
    */
    function add_queryvars( $query_vars ){

        $query_vars[] = 'pid';
        $query_vars[] = 'pageid';
        $query_vars[] = 'nggpage';
        $query_vars[] = 'gallery';
        $query_vars[] = 'album';
        $query_vars[] = 'gallerytag';
        $query_vars[] = 'show';
        $query_vars[] = 'callback';

        return $query_vars;
    }

    /**
    * rewrite the blog title if the gallery is used
    */
    function rewrite_title($title) {

        $new_title = '';
        // the separataor
        $sep = ' &laquo; ';

        // $_GET from wp_query
        $pid     = get_query_var('pid');
        $pageid  = get_query_var('pageid');
        $nggpage = get_query_var('nggpage');
        $gallery = get_query_var('gallery');
        $album   = get_query_var('album');
        $tag     = get_query_var('gallerytag');
        $show    = get_query_var('show');

        //TODO: I could parse for the Picture name , gallery etc, but this increase the queries
        //TODO: Class nggdb need to cache the query for the nggfunctions.php

        if ( $show == 'slide' )
            $new_title .= __('Slideshow', 'nggallery') . $sep ;
        elseif ( $show == 'show' )
            $new_title .= __('Gallery', 'nggallery') . $sep ;

        if ( !empty($pid) )
            $new_title .= __('Picture', 'nggallery') . ' ' . esc_attr($pid) . $sep ;

        if ( !empty($album) )
            $new_title .= __('Album', 'nggallery') . ' ' . esc_attr($album) . $sep ;

        if ( !empty($gallery) )
            $new_title .= __('Gallery', 'nggallery') . ' ' . esc_attr($gallery) . $sep ;

        if ( !empty($nggpage) )
            $new_title .= __('Page', 'nggallery') . ' ' . esc_attr($nggpage) . $sep ;

        //esc_attr should avoid XSS like http://domain/?gallerytag=%3C/title%3E%3Cscript%3Ealert(document.cookie)%3C/script%3E
        if ( !empty($tag) )
            $new_title .= esc_attr($tag) . $sep;

        //prepend the data
        $title = $new_title . $title;

        return $title;
    }

    /**
     * Canonical support for a better SEO (Dupilcat content), not longer nedded for Wp 2.9
     * See : http://googlewebmastercentral.blogspot.com/2009/02/specify-your-canonical.html
     *
     * @deprecated
     * @return string $meta
     */
    function add_canonical_meta()
    {
            // create the meta link
            $meta  = "\n<link rel='canonical' href='" . get_permalink() ."' />";
            // add a filter for SEO plugins, so they can remove it
            echo apply_filters('ngg_add_canonical_meta', $meta);

        return;
    }

    /**
    * The actual rewrite rules
    */
    function RewriteRules($wp_rewrite) {
        global $ngg;

        $rewrite_rules = array (
            // XML request
            $this->slug . '/slideshow/([0-9]+)/?$' => 'index.php?imagerotator=true&gid=$matches[1]'
        );

        $rewrite_rules = array_merge($rewrite_rules, $this->generate_rewrite_rules() );
        $wp_rewrite->rules = array_merge($rewrite_rules, $wp_rewrite->rules);
    }

    /**
     * Mainly a copy of the same function in wp-includes\rewrite.php
     * Adding the NGG tags to each post & page. Never found easier and proper way to handle this with other functions.
     *
     * @return array the permalink structure
     */
    function generate_rewrite_rules() {
        global $wp_rewrite;

        $rewrite_rules = array();
        $permalink_structure =  $wp_rewrite->permalink_structure;

        //get everything up to the first rewrite tag
        $front = substr($permalink_structure, 0, strpos($permalink_structure, '%'));
        //build an array of the tags (note that said array ends up being in $tokens[0])
        preg_match_all('/%.+?%/', $permalink_structure, $tokens);

        $num_tokens = count($tokens[0]);

        $this->index = $wp_rewrite->index; //probably 'index.php'

        //build a list from the rewritecode and queryreplace arrays, that will look something like
        //tagname=$matches[i] where i is the current $i
        for ( $i = 0; $i < $num_tokens; ++$i ) {
            if ( 0 < $i )
                $queries[$i] = $queries[$i - 1] . '&';
            else
                $queries[$i] = '';

            $query_token = str_replace($wp_rewrite->rewritecode, $wp_rewrite->queryreplace, $tokens[0][$i]) . $wp_rewrite->preg_index($i+1);
            $queries[$i] .= $query_token;
        }

        //get the structure, minus any cruft (stuff that isn't tags) at the front
        $structure = $permalink_structure;
        if ( $front != '/' )
            $structure = str_replace($front, '', $structure);

        //create a list of dirs to walk over, making rewrite rules for each level
        //so for example, a $structure of /%year%/%month%/%postname% would create
        //rewrite rules for /%year%/, /%year%/%month%/ and /%year%/%month%/%postname%
        $structure = trim($structure, '/');

        //strip slashes from the front of $front
        $struct = preg_replace('|^/+|', '', $front);

        //get the struct for this dir, and trim slashes off the front
        $struct .= $structure . '/'; //accumulate. see comment near explode('/', $structure) above
        $struct = ltrim($struct, '/');

        //replace tags with regexes
        $match = str_replace($wp_rewrite->rewritecode, $wp_rewrite->rewritereplace, $struct);

        //make a list of tags, and store how many there are in $num_toks
        $num_toks = preg_match_all('/%.+?%/', $struct, $toks);

        //get the 'tagname=$matches[i]'
        $query = ( isset($queries) && is_array($queries) ) ? $queries[$num_toks - 1] : '';

        if ( $num_toks ) {
            // In the case we build for each and every page ( based on a simple %pagename% rule ) the rewrite rules,
            // we need to add them first, then the post rules
            if ( $wp_rewrite->use_verbose_page_rules )
                $rewrite_rules = array_merge ( $this->page_rewrite_rules(), $this->add_rewrite_rules( $match, $query, $num_toks ) );
            else
                $rewrite_rules = array_merge ( $this->add_rewrite_rules( $match, $query, $num_toks ), $this->page_rewrite_rules() );
        }

        return $rewrite_rules;
    }

    /**
     * Retrieve all of the rewrite rules for pages.
     *
     * If the 'use_verbose_page_rules' property is false, then there will only
     * be a single rewrite rule for pages for those matching '%pagename%'. With
     * the property set to true, the attachments and the pages will be added for
     * each individual attachment URI and page URI, respectively.
     *
     * @since 1.8.3
     * @access public
     * @return array
     */
    function page_rewrite_rules() {
        global $wp_rewrite;

        $rewrite_rules = array();

        if ( ! $wp_rewrite->use_verbose_page_rules ) {

            $rewrite_rules = $this->add_rewrite_rules( "(.+?)/", 'pagename=$matches[1]', 1 );
            return $rewrite_rules;
        }

        $page_uris = $wp_rewrite->page_uri_index();
        $uris = $page_uris[0];

        if ( is_array( $uris ) ) {

            foreach ( $uris as $uri => $pagename ) {
                $rewrite_rules = array_merge($rewrite_rules, $this->add_rewrite_rules( "($uri)/", 'pagename=$matches[1]', 1 ) );
            }

        }

        return $rewrite_rules;
    }

    /**
     * Build the final structure of the rewrite rules based on match/query
     *
     * @since 1.8.3
     * @param string $match
     * @param string $query
     * @param int $num_toks
     * @return array
     */
    function add_rewrite_rules( $match, $query, $num_toks ) {
        global $wp_rewrite;

        $rewrite_rules = array();

        foreach ( $this->ngg_rules as $regex => $new_query) {

            // first add your nextgen slug
            $final_match = $match . $this->slug;

            //add regex parameter
            $final_match .= $regex;
            // check how often we found matches fields
            $count = substr_count($new_query, '[matches]');
            // we need to know how many tags before
            $offset = $num_toks;
            // build the query and count up the matches : tagname=$matches[x]
            for ( $i = 0; $i < $count; $i++ ) {
                $new_query = preg_replace('/\[matches\]/', '$matches[' . ++$offset . ']', $new_query, 1);
            }
            $final_query = $query . $new_query;

            //close the match and finalise the query
            $final_match .= '?$';
            $final_query = $this->index . '?' . $final_query;

            $rewrite_rules = array_merge($rewrite_rules, array($final_match => $final_query));

        }

        return $rewrite_rules;
    }

}  // of nggRewrite CLASS

?>