xref: /plugin/combo/action/metacanonical.php (revision 531e725cdb5a652164f2d97f556304e31f720033)

<?php

use ComboStrap\MetadataUtility;
use ComboStrap\PluginUtility;
use ComboStrap\Page;

if (!defined('DOKU_INC')) die();

/**
 *
 *
 *   * The name of the file should be the last name of the class
 *   * There should be only one name
 */
class action_plugin_combo_metacanonical extends DokuWiki_Action_Plugin
{

    /**
     * The conf
     */
    const CANONICAL_LAST_NAMES_COUNT_CONF = 'MinimalNamesCountForAutomaticCanonical';


    function __construct()
    {
        // enable direct access to language strings
        // ie $this->lang
        $this->setupLocale();
    }

    public function register(Doku_Event_Handler $controller)
    {
        $controller->register_hook('TPL_METAHEADER_OUTPUT', 'BEFORE', $this, 'metaCanonicalProcessing', array());
    }

    /**
     * Dokuwiki has already a canonical methodology
     * https://www.dokuwiki.org/canonical
     *
     * @param $event
     */
    function metaCanonicalProcessing($event)
    {

        global $ID;
        if (empty($ID)){
            // $_SERVER['SCRIPT_NAME']== "/lib/exe/mediamanager.php"
            // $ID is null
            return;
        }

        $page = new Page($ID);

        /**
         * No canonical for slot page
         */
        if ($page->isSlot()) {
            return;
        }

        /**
         * Where do we pick the canonical URL
         */
        /**
         * Canonical from meta
         *
         * FYI: The creation of the link was extracted from
         * {@link wl()} that call {@link idfilter()} that performs just a replacement
         * Calling the wl function will not work because
         * {@link wl()} use the constant DOKU_URL that is set before any test via getBaseURL(true)
         */


        $canonicalUrl = $page->getCanonicalUrlOrDefault();

        /**
         * Replace the meta entry
         *
         * First search the key of the meta array
         */
        $canonicalKey = "";
        $canonicalRelArray = array("rel" => "canonical", "href" => $canonicalUrl);
        foreach ($event->data['link'] as $key => $link) {
            if ($link["rel"] == "canonical") {
                $canonicalKey = $key;
            }
        }
        if ($canonicalKey != "") {
            // Update
            $event->data['link'][$canonicalKey] = $canonicalRelArray;
        } else {
            // Add
            $event->data['link'][] = $canonicalRelArray;
        }

        /**
         * Add the Og canonical meta
         * https://developers.facebook.com/docs/sharing/webmasters/getting-started/versioned-link/
         */
        $canonicalOgKeyKey = "";
        $canonicalPropertyKey = "og:url";
        $canonicalOgArray = array("property" => $canonicalPropertyKey, "content" => $canonicalUrl);
        // Search if the canonical property is already present
        foreach ($event->data['meta'] as $key => $meta) {
            if (array_key_exists("property",$meta)) {
                /**
                 * We may have several properties
                 */
                if ($meta["property"] == $canonicalPropertyKey) {
                    $canonicalOgKeyKey = $key;
                }
            }
        }
        if ($canonicalOgKeyKey != "") {
            // Update
            $event->data['meta'][$canonicalOgKeyKey] = $canonicalOgArray;
        } else {
            // Add
            $event->data['meta'][] = $canonicalOgArray;
        }

    }

}