Proyectos de Subversion Moodle

<?php

// This file is part of Moodle - https://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 <https://www.gnu.org/licenses/>.

namespace core\context;

use core\context;

use stdClass;

use coding_exception, moodle_url;

/**

 * Course category context class

 *

 * @package   core_access

 * @category  access

 * @copyright Petr Skoda

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

 * @since     Moodle 4.2

 */

class coursecat extends context {

    /** @var int numeric context level value matching legacy CONTEXT_COURSECAT */

    public const LEVEL = 40;

    /**

     * Please use \core\context\coursecat::instance($coursecatid) if you need the instance of context.

     * Alternatively if you know only the context id use \core\context::instance_by_id($contextid)

     *

     * @param stdClass $record

     */

    protected function __construct(stdClass $record) {

        parent::__construct($record);

        if ($record->contextlevel != self::LEVEL) {

            throw new coding_exception('Invalid $record->contextlevel in core\context\coursecat constructor.');

        }

    }

    /**

     * Returns short context name.

     *

     * @since Moodle 4.2

     *

     * @return string

     */

    public static function get_short_name(): string {

        return 'coursecat';

    }

    /**

     * Returns human readable context level name.

     *

     * @return string the human readable context level name.

     */

    public static function get_level_name() {

        return get_string('category');

    }

    /**

     * Returns human readable context identifier.

     *

     * @param boolean $withprefix whether to prefix the name of the context with Category

     * @param boolean $short does not apply to course categories

     * @param boolean $escape Whether the returned name of the context is to be HTML escaped or not.

     * @return string the human readable context name.

     */

    public function get_context_name($withprefix = true, $short = false, $escape = true) {

        global $DB;

        $name = '';

        if ($category = $DB->get_record('course_categories', array('id' => $this->_instanceid))) {

            if ($withprefix) {

                $name = get_string('category').': ';

            }

            if (!$escape) {

                $name .= format_string($category->name, true, array('context' => $this, 'escape' => false));

            } else {

                $name .= format_string($category->name, true, array('context' => $this));

            }

        }

        return $name;

    }

    /**

     * Returns the most relevant URL for this context.

     *

     * @return moodle_url

     */

    public function get_url() {

        return new moodle_url('/course/index.php', array('categoryid' => $this->_instanceid));

    }

    /**

     * Returns context instance database name.

     *

     * @return string|null table name for all levels except system.

     */

    protected static function get_instance_table(): ?string {

        return 'course_categories';

    }

    /**

     * Returns list of columns that can be used from behat

     * to look up context by reference.

     *

     * @return array list of column names from instance table

     */

    protected static function get_behat_reference_columns(): array {

        return ['idnumber'];

    }

    /**

     * Returns list of all role archetypes that are compatible

     * with role assignments in context level.

     * @since Moodle 4.2

     *

     * @return int[]

     */

    protected static function get_compatible_role_archetypes(): array {

        return ['manager', 'coursecreator'];

    }

    /**

     * Returns list of all possible parent context levels.

     * @since Moodle 4.2

     *

     * @return int[]

     */

    public static function get_possible_parent_levels(): array {

        return [system::LEVEL, self::LEVEL];

    }

    /**

     * Returns array of relevant context capability records.

     *

     * @param string $sort

     * @return array

     */

    public function get_capabilities(string $sort = self::DEFAULT_CAPABILITY_SORT) {

        global $DB;

        $levels = \core\context_helper::get_child_levels(self::LEVEL);

        $levels[] = self::LEVEL;

        return $DB->get_records_list('capabilities', 'contextlevel', $levels, $sort);

    }

    /**

     * Returns course category context instance.

     *

     * @param int $categoryid id from {course_categories} table

     * @param int $strictness

     * @return coursecat|false context instance

     */

    public static function instance($categoryid, $strictness = MUST_EXIST) {

        global $DB;

        if ($context = context::cache_get(self::LEVEL, $categoryid)) {

            return $context;

        }

        if (!$record = $DB->get_record('context', array('contextlevel' => self::LEVEL, 'instanceid' => $categoryid))) {

            if ($category = $DB->get_record('course_categories', array('id' => $categoryid), 'id,parent', $strictness)) {

                if ($category->parent) {

                    $parentcontext = self::instance($category->parent);

                    $record = context::insert_context_record(self::LEVEL, $category->id, $parentcontext->path);

                } else {

                    $record = context::insert_context_record(self::LEVEL, $category->id, '/'.SYSCONTEXTID, 0);

                }

            }

        }

        if ($record) {

            $context = new coursecat($record);

            context::cache_add($context);

            return $context;

        }

        return false;

    }

    /**

     * Returns immediate child contexts of category and all subcategories,

     * children of subcategories and courses are not returned.

     *

     * @return array

     */

    public function get_child_contexts() {

        global $DB;

        if (empty($this->_path) || empty($this->_depth)) {

            debugging('Can not find child contexts of context '.$this->_id.' try rebuilding of context paths');

            return array();

        }

        $sql = "SELECT ctx.*

                  FROM {context} ctx

                 WHERE ctx.path LIKE ? AND (ctx.depth = ? OR ctx.contextlevel = ?)";

        $params = array($this->_path.'/%', $this->depth + 1, self::LEVEL);

        $records = $DB->get_records_sql($sql, $params);

        $result = array();

        foreach ($records as $record) {

            $result[$record->id] = context::create_instance_from_record($record);

        }

        return $result;

    }

    /**

     * Create missing context instances at course category context level

     */

    protected static function create_level_instances() {

        global $DB;

        $sql = "SELECT ".self::LEVEL.", cc.id

                  FROM {course_categories} cc

                 WHERE NOT EXISTS (SELECT 'x'

                                     FROM {context} cx

                                    WHERE cc.id = cx.instanceid AND cx.contextlevel=".self::LEVEL.")";

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

        foreach ($contextdata as $context) {

            context::insert_context_record(self::LEVEL, $context->id, null);

        }

        $contextdata->close();

    }

    /**

     * Returns sql necessary for purging of stale context instances.

     *

     * @return string cleanup SQL

     */

    protected static function get_cleanup_sql() {

        $sql = "

                  SELECT c.*

                    FROM {context} c

         LEFT OUTER JOIN {course_categories} cc ON c.instanceid = cc.id

                   WHERE cc.id IS NULL AND c.contextlevel = ".self::LEVEL."

               ";

        return $sql;

    }

    /**

     * Rebuild context paths and depths at course category context level.

     *

     * @param bool $force

     */

    protected static function build_paths($force) {

        global $DB;

        if ($force || $DB->record_exists_select('context', "contextlevel = ".self::LEVEL." AND (depth = 0 OR path IS NULL)")) {

            if ($force) {

                $ctxemptyclause = $emptyclause = '';

            } else {

                $ctxemptyclause = "AND (ctx.path IS NULL OR ctx.depth = 0)";

                $emptyclause = "AND ({context}.path IS NULL OR {context}.depth = 0)";

            }

            $base = '/'.SYSCONTEXTID;

            // Normal top level categories.

            $sql = "UPDATE {context}

                       SET depth=2,

                           path=".$DB->sql_concat("'$base/'", 'id')."

                     WHERE contextlevel=".self::LEVEL."

                           AND EXISTS (SELECT 'x'

                                         FROM {course_categories} cc

                                        WHERE cc.id = {context}.instanceid AND cc.depth=1)

                           $emptyclause";

            $DB->execute($sql);

            // Deeper categories - one query per depthlevel.

            $maxdepth = $DB->get_field_sql("SELECT MAX(depth) FROM {course_categories}");

            for ($n = 2; $n <= $maxdepth; $n++) {

                $sql = "INSERT INTO {context_temp} (id, path, depth, locked)

                        SELECT ctx.id, ".$DB->sql_concat('pctx.path', "'/'", 'ctx.id').", pctx.depth+1, ctx.locked

                          FROM {context} ctx

                          JOIN {course_categories} cc ON (cc.id = ctx.instanceid AND ctx.contextlevel = ".self::LEVEL."

                               AND cc.depth = $n)

                          JOIN {context} pctx ON (pctx.instanceid = cc.parent AND pctx.contextlevel = ".self::LEVEL.")

                         WHERE pctx.path IS NOT NULL AND pctx.depth > 0

                               $ctxemptyclause";

                $trans = $DB->start_delegated_transaction();

                $DB->delete_records('context_temp');

                $DB->execute($sql);

                context::merge_context_temp_table();

                $DB->delete_records('context_temp');

                $trans->allow_commit();

            }

        }

    }

}