<?php

/**
 * W3 PgCache plugin - administrative interface
 */
if (!defined('W3TC')) {
    die();
}

w3_require_once(W3TC_INC_DIR . '/functions/file.php');
w3_require_once(W3TC_INC_DIR . '/functions/rule.php');
w3_require_once(W3TC_LIB_W3_DIR . '/Plugin.php');

/**
 * Class W3_Plugin_PgCacheAdmin
 */
class W3_Plugin_PgCacheAdmin extends W3_Plugin {
    function cleanup() {
        // We check to see if we're dealing with a cluster
        $config = w3_instance('W3_Config');
        $is_cluster = $config->get_boolean('cluster.messagebus.enabled');

        // If we are, we notify the subscribers. If not, we just cleanup in here
        if ($is_cluster) {
            $this->cleanup_cluster();
        } else {
            $this->cleanup_local();
        }

    }
    
    /**
     * Will trigger notifications to be sent to the cluster to 'order' them to clean their page cache.
     */
    function cleanup_cluster() {
        $sns_client = w3_instance('W3_Enterprise_SnsClient');
        $sns_client->pgcache_cleanup();
    }
    
    function cleanup_local() {
        $engine = $this->_config->get_string('pgcache.engine');

        switch ($engine) {
            case 'file':
                w3_require_once(W3TC_LIB_W3_DIR . '/Cache/File/Cleaner.php');

                $w3_cache_file_cleaner = new W3_Cache_File_Cleaner(array(
                    'cache_dir' => w3_cache_blog_dir('page'),
                    'clean_timelimit' => $this->_config->get_integer('timelimit.cache_gc')
                ));

                $w3_cache_file_cleaner->clean();
                break;

            case 'file_generic':
                w3_require_once(W3TC_LIB_W3_DIR . '/Cache/File/Cleaner/Generic.php');

                if (w3_get_blog_id() == 0)
                    $flush_dir = W3TC_CACHE_PAGE_ENHANCED_DIR;
                else
                    $flush_dir = W3TC_CACHE_PAGE_ENHANCED_DIR . '/' . w3_get_domain(w3_get_host());

                $w3_cache_file_cleaner_generic = new W3_Cache_File_Cleaner_Generic(array(
                    'exclude' => array(
                        '.htaccess'
                    ),
                    'cache_dir' => $flush_dir,
                    'expire' => $this->_config->get_integer('browsercache.html.lifetime'),
                    'clean_timelimit' => $this->_config->get_integer('timelimit.cache_gc')
                ));

                $w3_cache_file_cleaner_generic->clean();
                break;
        }
    }

    /**
     * Prime cache
     *
     * @param integer $start
     * @return void
     */
    function prime($start = 0) {
        $start = (int) $start;

        /**
         * Don't start cache prime if queues are still scheduled
         */
        if ($start == 0) {
            $crons = _get_cron_array();

            foreach ($crons as $timestamp => $hooks) {
                foreach ($hooks as $hook => $keys) {
                    foreach ($keys as $key => $data) {
                        if ($hook == 'w3_pgcache_prime' && count($data['args'])) {
                            return;
                        }
                    }
                }
            }
        }

        $interval = $this->_config->get_integer('pgcache.prime.interval');
        $limit = $this->_config->get_integer('pgcache.prime.limit');
        $sitemap = $this->_config->get_string('pgcache.prime.sitemap');

        /**
         * Parse XML sitemap
         */
        $urls = $this->parse_sitemap($sitemap);

        /**
         * Queue URLs
         */
        $queue = array_slice($urls, $start, $limit);

        if (count($urls) > ($start + $limit)) {
            wp_schedule_single_event(time() + $interval, 'w3_pgcache_prime', array(
                $start + $limit
            ));
        }

        /**
         * Make HTTP requests and prime cache
         */
        w3_require_once(W3TC_INC_DIR . '/functions/http.php');
        w3_require_once(W3TC_INC_DIR . '/functions/url.php');

        // use empty user-agent since by default we use W3TC-powered by
        // which blocks caching
        foreach ($queue as $url)
            w3_http_get($url, array('user-agent' => ''));
    }

    /**
     * Parses sitemap
     *
     * @param string $url
     * @return array
     */
    function parse_sitemap($url) {
        w3_require_once(W3TC_INC_DIR . '/functions/http.php');

        $urls = array();
        $response = w3_http_get($url);

        if (!is_wp_error($response) && $response['response']['code'] == 200) {
            $url_matches = null;
            $sitemap_matches = null;

            if (preg_match_all('~<sitemap>(.*?)</sitemap>~is', $response['body'], $sitemap_matches)) {
                $loc_matches = null;

                foreach ($sitemap_matches[1] as $sitemap_match) {
                    if (preg_match('~<loc>(.*?)</loc>~is', $sitemap_match, $loc_matches)) {
                        $loc = trim($loc_matches[1]);

                        if ($loc) {
                            $urls = array_merge($urls, $this->parse_sitemap($loc));
                        }
                    }
                }
            } elseif (preg_match_all('~<url>(.*?)</url>~is', $response['body'], $url_matches)) {
                $locs = array();
                $loc_matches = null;
                $priority_matches = null;

                foreach ($url_matches[1] as $url_match) {
                    $loc = '';
                    $priority = 0;

                    if (preg_match('~<loc>(.*?)</loc>~is', $url_match, $loc_matches)) {
                        $loc = trim($loc_matches[1]);
                    }

                    if (preg_match('~<priority>(.*?)</priority>~is', $url_match, $priority_matches)) {
                        $priority = (double) trim($priority_matches[1]);
                    }

                    if ($loc && $priority) {
                        $locs[$loc] = $priority;
                    }
                }

                arsort($locs);

                $urls = array_keys($locs);
            }
        }

        return $urls;
    }

    /**
     * Returns required rules for module
     * @return array
     */
    function get_required_rules() {
        $e = w3_instance('W3_Plugin_PgCacheAdminEnvironment');
        return $e->get_required_rules();
    }


    /**
     * Makes get requests to url specific to a post, its permalink
     * @param $post_id
     * @return boolean returns true on success
     */
    public function prime_post($post_id) {
        /** @var $purges W3_SharedPageUrls */
        $purges = w3_instance('W3_SharedPageUrls');
        $post_urls = $purges->get_post_urls($post_id);
        /**
         * Make HTTP requests and prime cache
         */
        w3_require_once(W3TC_INC_DIR . '/functions/http.php');
        w3_require_once(W3TC_INC_DIR . '/functions/url.php');

        foreach ($post_urls as $url) {
            $result = w3_http_get($url, array('user-agent' => ''));
            if (is_wp_error($result))
                return false;
        }
        return true;
    }
}