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/>.

/**

 * Forum vault class.

 *

 * @package    mod_forum

 * @copyright  2019 Ryan Wyllie <ryan@moodle.com>

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

 */

namespace mod_forum\local\vaults;

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

use mod_forum\local\entities\forum as forum_entity;

use mod_forum\local\vaults\preprocessors\extract_context as extract_context_preprocessor;

use mod_forum\local\vaults\preprocessors\extract_record as extract_record_preprocessor;

use core\dml\table as dml_table;

use context_helper;

/**

 * Forum vault class.

 *

 * This should be the only place that accessed the database.

 *

 * This uses the repository pattern. See:

 * https://designpatternsphp.readthedocs.io/en/latest/More/Repository/README.html

 *

 * @copyright  2019 Ryan Wyllie <ryan@moodle.com>

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

 */

class forum extends db_table_vault {

    /** The table for this vault */

    private const TABLE = 'forum';

    /**

     * Get the table alias.

     *

     * @return string

     */

    protected function get_table_alias(): string {

        return 'f';

    }

    /**

     * Build the SQL to be used in get_records_sql.

     *

     * @param string|null $wheresql Where conditions for the SQL

     * @param string|null $sortsql Order by conditions for the SQL

     * @param int|null $userid The user ID

     * @return string

     */

    protected function generate_get_records_sql(string $wheresql = null, string $sortsql = null, ?int $userid = null): string {

        $db = $this->get_db();

        $alias = $this->get_table_alias();

        $thistable = new dml_table(self::TABLE, $alias, $alias);

        $cmtable = new dml_table('course_modules', 'cm', 'cm_');

        $coursetable = new dml_table('course', 'c', 'c_');

        $fields = implode(', ', [

            $thistable->get_field_select(),

            context_helper::get_preload_record_columns_sql('ctx'),

            $cmtable->get_field_select(),

            $coursetable->get_field_select(),

        ]);

        $tables = $thistable->get_from_sql();

        $tables .= " JOIN {modules} m ON m.name = 'forum'";

        $tables .= " JOIN " . $cmtable->get_from_sql() . " ON cm.module = m.id AND cm.instance = {$alias}.id";

        $tables .= ' JOIN {context} ctx ON ctx.contextlevel = ' . CONTEXT_MODULE .  ' AND ctx.instanceid = cm.id';

        $tables .= " JOIN " . $coursetable->get_from_sql() . " ON c.id = {$alias}.course";

        $selectsql = 'SELECT ' . $fields . ' FROM ' . $tables;

        $selectsql .= $wheresql ? ' WHERE ' . $wheresql : '';

        $selectsql .= $sortsql ? ' ORDER BY ' . $sortsql : '';

        return $selectsql;

    }

    /**

     * Get a list of preprocessors to execute on the DB results before being converted

     * into entities.

     *

     * @return array

     */

    protected function get_preprocessors(): array {

        return array_merge(

            parent::get_preprocessors(),

            [

                'forum' => new extract_record_preprocessor(self::TABLE, $this->get_table_alias()),

                'course_module' => new extract_record_preprocessor('course_modules', 'cm_'),

                'course' => new extract_record_preprocessor('course', 'c_'),

                'context' => new extract_context_preprocessor(),

            ]

        );

    }

    /**

     * Convert the DB records into forum entities.

     *

     * @param array $results The DB records

     * @return forum_entity[]

     */

    protected function from_db_records(array $results): array {

        $entityfactory = $this->get_entity_factory();

        return array_map(function(array $result) use ($entityfactory) {

            [

                'forum' => $forumrecord,

                'course_module' => $coursemodule,

                'course' => $course,

                'context' => $context,

            ] = $result;

            return $entityfactory->get_forum_from_stdclass($forumrecord, $context, $coursemodule, $course);

        }, $results);

    }

    /**

     * Get the forum for the given course module id.

     *

     * @param int $id The course module id

     * @return forum_entity|null

     */

    public function get_from_course_module_id(int $id): ?forum_entity {

        $records = $this->get_from_course_module_ids([$id]);

        return count($records) ? array_shift($records) : null;

    }

    /**

     * Get the forums for the given course module ids

     *

     * @param int[] $ids The course module ids

     * @return forum_entity[]

     */

    public function get_from_course_module_ids(array $ids): array {

        $alias = $this->get_table_alias();

        list($insql, $params) = $this->get_db()->get_in_or_equal($ids);

        $wheresql = 'cm.id ' . $insql;

        $sql = $this->generate_get_records_sql($wheresql);

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

        return $this->transform_db_records_to_entities($records);

    }

    /**

     * Get the forum entity for the given post id.

     *

     * @param int $id The course module id

     * @return forum_entity|null

     */

    public function get_from_post_id(int $id): ?forum_entity {

        $alias = $this->get_table_alias();

        $thistable = new dml_table(self::TABLE, $alias, $alias);

        $coursemoduletable = new dml_table('course_modules', 'cm', 'cm_');

        $coursetable = new dml_table('course', 'c', 'c_');

        $tablefields = $thistable->get_field_select();

        $coursemodulefields = $coursemoduletable->get_field_select();

        $coursefields = $coursetable->get_field_select();

        $fields = implode(', ', [

            $tablefields,

            context_helper::get_preload_record_columns_sql('ctx'),

            $coursemodulefields,

            $coursefields,

        ]);

        $tables = "{forum_posts} p";

        $tables .= " JOIN {forum_discussions} d ON d.id = p.discussion";

        $tables .= ' JOIN {' . self::TABLE . "} {$alias} ON {$alias}.id = d.forum";

        $tables .= " JOIN {modules} m ON m.name = 'forum'";

        $tables .= " JOIN {course_modules} cm ON cm.module = m.id AND cm.instance = {$alias}.id";

        $tables .= ' JOIN {context} ctx ON ctx.contextlevel = ' . CONTEXT_MODULE .  ' AND ctx.instanceid = cm.id';

        $tables .= " JOIN {course} c ON c.id = {$alias}.course";

        $sql = "SELECT {$fields} FROM {$tables} WHERE p.id = :postid";

        $records = $this->get_db()->get_records_sql($sql, [

            'postid' => $id,

        ]);

        $records = $this->transform_db_records_to_entities($records);

        return count($records) ? array_shift($records) : null;

    }

}