Proyectos de Subversion Moodle

<?php

// This file is part of Moodle - http://moodle.org/

//

// Moodle is free software: you can redistribute it and/or modify

// it under the terms of the GNU General Public License as published by

// the Free Software Foundation, either version 3 of the License, or

// (at your option) any later version.

//

// Moodle is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

// GNU General Public License for more details.

//

// You should have received a copy of the GNU General Public License

// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**

 * Entry caching for glossary filter.

 *

 * @package    mod_glossary

 * @copyright  2014 Petr Skoda

 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

namespace mod_glossary\local;

defined('MOODLE_INTERNAL') || die();

/**

 * Concept caching for glossary filter.

 *

 * @package    mod_glossary

 * @copyright  2014 Petr Skoda

 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

class concept_cache {

    /**

     * Event observer, do not call directly.

     * @param \core\event\course_module_updated $event

     */

    public static function cm_updated(\core\event\course_module_updated $event) {

        if ($event->other['modulename'] !== 'glossary') {

            return;

        }

        // We do not know what changed exactly, so let's reset everything that might be affected.

        concept_cache::reset_course_muc($event->courseid);

        concept_cache::reset_global_muc();

    }

    /**

     * Reset concept related caches.

     * @param bool $phpunitreset

     */

    public static function reset_caches($phpunitreset = false) {

        if ($phpunitreset) {

            return;

        }

        $cache = \cache::make('mod_glossary', 'concepts');

        $cache->purge();

    }

    /**

     * Reset the cache for course concepts.

     * @param int $courseid

     */

    public static function reset_course_muc($courseid) {

        if (empty($courseid)) {

            return;

        }

        $cache = \cache::make('mod_glossary', 'concepts');

        $cache->delete((int)$courseid);

    }

    /**

     * Reset the cache for global concepts.

     */

    public static function reset_global_muc() {

        $cache = \cache::make('mod_glossary', 'concepts');

        $cache->delete(0);

    }

    /**

     * Utility method to purge caches related to given glossary.

     * @param \stdClass $glossary

     */

    public static function reset_glossary($glossary) {

        if (!$glossary->usedynalink) {

            return;

        }

        self::reset_course_muc($glossary->course);

        if ($glossary->globalglossary) {

            self::reset_global_muc();

        }

    }

    /**

     * Fetch concepts for given glossaries.

     * @param int[] $glossaries

     * @return array

     */

    protected static function fetch_concepts(array $glossaries) {

        global $DB;

        $glossarylist = implode(',', $glossaries);

        $sql = "SELECT id, glossaryid, concept, casesensitive, 0 AS category, fullmatch

                  FROM {glossary_entries}

                 WHERE glossaryid IN ($glossarylist) AND usedynalink = 1 AND approved = 1

                 UNION

                SELECT id, glossaryid, name AS concept, 1 AS casesensitive, 1 AS category, 1 AS fullmatch

                  FROM {glossary_categories}

                 WHERE glossaryid IN ($glossarylist) AND usedynalink = 1

                UNION

                SELECT ge.id, ge.glossaryid, ga.alias AS concept, ge.casesensitive, 0 AS category, ge.fullmatch

                  FROM {glossary_alias} ga

                  JOIN {glossary_entries} ge ON (ga.entryid = ge.id)

                 WHERE ge.glossaryid IN ($glossarylist) AND ge.usedynalink = 1 AND ge.approved = 1";

        $concepts = array();

        $rs = $DB->get_recordset_sql($sql);

        foreach ($rs as $concept) {

            $currentconcept = trim($concept->concept);

            // Turn ampersands into & but keep HTML format for filters.

            $currentconcept = replace_ampersands_not_followed_by_entity($currentconcept);

            if (empty($currentconcept)) {

                continue;

            }

            // Rule out any small integers, see MDL-1446.

            if (is_number($currentconcept) and $currentconcept < 1000) {

                continue;

            }

            $concept->concept = $currentconcept;

            $concepts[$concept->glossaryid][] = $concept;

        }

        $rs->close();

        return $concepts;

    }

    /**

     * Get all linked concepts from course.

     * @param int $courseid

     * @return array

     */

    protected static function get_course_concepts($courseid) {

        global $DB;

        if (empty($courseid)) {

            return array(array(), array());

        }

        $courseid = (int)$courseid;

        // Get info on any glossaries in this course.

        $modinfo = get_fast_modinfo($courseid);

        $cminfos = $modinfo->get_instances_of('glossary');

        if (!$cminfos) {

            // No glossaries in this course, so don't do any work.

            return array(array(), array());

        }

        $cache = \cache::make('mod_glossary', 'concepts');

        $data = $cache->get($courseid);

        if (is_array($data)) {

            list($glossaries, $allconcepts) = $data;

        } else {

            // Find all course glossaries.

            $sql = "SELECT g.id, g.name

                      FROM {glossary} g

                      JOIN {course_modules} cm ON (cm.instance = g.id)

                      JOIN {modules} m ON (m.name = 'glossary' AND m.id = cm.module)

                     WHERE g.usedynalink = 1 AND g.course = :course AND cm.visible = 1 AND m.visible = 1

                  ORDER BY g.globalglossary, g.id";

            $glossaries = $DB->get_records_sql_menu($sql, array('course' => $courseid));

            if (!$glossaries) {

                $data = array(array(), array());

                $cache->set($courseid, $data);

                return $data;

            }

            foreach ($glossaries as $id => $name) {

                $name = str_replace(':', '-', $name);

                $glossaries[$id] = $name;

            }

            $allconcepts = self::fetch_concepts(array_keys($glossaries));

            foreach ($glossaries as $gid => $unused) {

                if (!isset($allconcepts[$gid])) {

                    unset($glossaries[$gid]);

                }

            }

            if (!$glossaries) {

                // This means there are no interesting concepts in the existing glossaries.

                $data = array(array(), array());

                $cache->set($courseid, $data);

                return $data;

            }

            $cache->set($courseid, array($glossaries, $allconcepts));

        }

        $concepts = $allconcepts;

        // Verify access control to glossary instances.

        foreach ($concepts as $modid => $unused) {

            if (!isset($cminfos[$modid])) {

                // This should not happen.

                unset($concepts[$modid]);

                unset($glossaries[$modid]);

                continue;

            }

            if (!$cminfos[$modid]->uservisible) {

                unset($concepts[$modid]);

                unset($glossaries[$modid]);

                continue;

            }

        }

        return array($glossaries, $concepts);

    }

    /**

     * Get all linked global concepts.

     * @return array

     */

    protected static function get_global_concepts() {

        global $DB;

        $cache = \cache::make('mod_glossary', 'concepts');

        $data = $cache->get(0);

        if (is_array($data)) {

            list($glossaries, $allconcepts) = $data;

        } else {

            // Find all global glossaries - no access control here.

            $sql = "SELECT g.id, g.name

                      FROM {glossary} g

                      JOIN {course_modules} cm ON (cm.instance = g.id)

                      JOIN {modules} m ON (m.name = 'glossary' AND m.id = cm.module)

                     WHERE g.usedynalink = 1 AND g.globalglossary = 1 AND cm.visible = 1 AND m.visible = 1

                  ORDER BY g.globalglossary, g.id";

            $glossaries = $DB->get_records_sql_menu($sql);

            if (!$glossaries) {

                $data = array(array(), array());

                $cache->set(0, $data);

                return $data;

            }

            foreach ($glossaries as $id => $name) {

                $name = str_replace(':', '-', $name);

                $glossaries[$id] = replace_ampersands_not_followed_by_entity($name);

            }

            $allconcepts = self::fetch_concepts(array_keys($glossaries));

            foreach ($glossaries as $gid => $unused) {

                if (!isset($allconcepts[$gid])) {

                    unset($glossaries[$gid]);

                }

            }

            $cache->set(0, array($glossaries, $allconcepts));

        }

        // NOTE: no access control is here because it would be way too expensive to check access

        //       to all courses that contain the global glossaries.

        return array($glossaries, $allconcepts);

    }

    /**

     * Get all concepts that should be linked in the given course.

     * @param int $courseid

     * @return array with two elements - array of glossaries and concepts for each glossary

     */

    public static function get_concepts($courseid) {

        list($glossaries, $concepts) = self::get_course_concepts($courseid);

        list($globalglossaries, $globalconcepts) = self::get_global_concepts();

        foreach ($globalconcepts as $gid => $cs) {

            if (!isset($concepts[$gid])) {

                $concepts[$gid] = $cs;

            }

        }

        foreach ($globalglossaries as $gid => $name) {

            if (!isset($glossaries[$gid])) {

                $glossaries[$gid] = $name;

            }

        }

        return array($glossaries, $concepts);

    }

}