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/>.

/**

 * Condition main class.

 *

 * @package availability_group

 * @copyright 2014 The Open University

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

 */

namespace availability_group;

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

/**

 * Condition main class.

 *

 * @package availability_group

 * @copyright 2014 The Open University

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

 */

class condition extends \core_availability\condition {

    /** @var array Array from group id => name */

    protected static $groupnames = array();

    /** @var int ID of group that this condition requires, or 0 = any group */

    protected $groupid;

    /**

     * Constructor.

     *

     * @param \stdClass $structure Data structure from JSON decode

     * @throws \coding_exception If invalid data structure.

     */

    public function __construct($structure) {

        // Get group id.

        if (!property_exists($structure, 'id')) {

            $this->groupid = 0;

        } else if (is_int($structure->id)) {

            $this->groupid = $structure->id;

        } else {

            throw new \coding_exception('Invalid ->id for group condition');

        }

    }

    public function save() {

        $result = (object)array('type' => 'group');

        if ($this->groupid) {

            $result->id = $this->groupid;

        }

        return $result;

    }

    public function is_available($not, \core_availability\info $info, $grabthelot, $userid) {

        $course = $info->get_course();

        $context = \context_course::instance($course->id);

        $allow = true;

        if (!has_capability('moodle/site:accessallgroups', $context, $userid)) {

            // Get all groups the user belongs to.

            $groups = $info->get_groups(0, $userid);

            if ($this->groupid) {

                $allow = in_array($this->groupid, $groups);

            } else {

                // No specific group. Allow if they belong to any group at all.

                $allow = $groups ? true : false;

            }

            // The NOT condition applies before accessallgroups (i.e. if you

            // set something to be available to those NOT in group X,

            // people with accessallgroups can still access it even if

            // they are in group X).

            if ($not) {

                $allow = !$allow;

            }

        }

        return $allow;

    }

    public function get_description($full, $not, \core_availability\info $info) {

        global $DB;

        if ($this->groupid) {

            // Need to get the name for the group. Unfortunately this requires

            // a database query. To save queries, get all groups for course at

            // once in a static cache.

            $course = $info->get_course();

            if (!array_key_exists($this->groupid, self::$groupnames)) {

                $coursegroups = $DB->get_records(

                        'groups', array('courseid' => $course->id), '', 'id, name');

                foreach ($coursegroups as $rec) {

                    self::$groupnames[$rec->id] = $rec->name;

                }

            }

            // If it still doesn't exist, it must have been misplaced.

            if (!array_key_exists($this->groupid, self::$groupnames)) {

                $name = get_string('missing', 'availability_group');

            } else {

                // Not safe to call format_string here; use the special function to call it later.

                $name = self::description_format_string(self::$groupnames[$this->groupid]);

            }

        } else {

            return get_string($not ? 'requires_notanygroup' : 'requires_anygroup',

                    'availability_group');

        }

        return get_string($not ? 'requires_notgroup' : 'requires_group',

                'availability_group', $name);

    }

    protected function get_debug_string() {

        return $this->groupid ? '#' . $this->groupid : 'any';

    }

    /**

     * Include this condition only if we are including groups in restore, or

     * if it's a generic 'same activity' one.

     *

     * @param int $restoreid The restore Id.

     * @param int $courseid The ID of the course.

     * @param base_logger $logger The logger being used.

     * @param string $name Name of item being restored.

     * @param base_task $task The task being performed.

     *

     * @return Integer groupid

     */

    public function include_after_restore($restoreid, $courseid, \base_logger $logger,

            $name, \base_task $task) {

        return !$this->groupid || $task->get_setting_value('groups');

    }

    public function update_after_restore($restoreid, $courseid, \base_logger $logger, $name) {

        global $DB;

        if (!$this->groupid) {

            return false;

        }

        $rec = \restore_dbops::get_backup_ids_record($restoreid, 'group', $this->groupid);

        if (!$rec || !$rec->newitemid) {

            // If we are on the same course (e.g. duplicate) then we can just

            // use the existing one.

            if ($DB->record_exists('groups',

                    array('id' => $this->groupid, 'courseid' => $courseid))) {

                return false;

            }

            // Otherwise it's a warning.

            $this->groupid = -1;

            $logger->process('Restored item (' . $name .

                    ') has availability condition on group that was not restored',

                    \backup::LOG_WARNING);

        } else {

            $this->groupid = (int)$rec->newitemid;

        }

        return true;

    }

    public function update_dependency_id($table, $oldid, $newid) {

        if ($table === 'groups' && (int)$this->groupid === (int)$oldid) {

            $this->groupid = $newid;

            return true;

        } else {

            return false;

        }

    }

    /**

     * Wipes the static cache used to store grouping names.

     */

    public static function wipe_static_cache() {

        self::$groupnames = array();

    }

    public function is_applied_to_user_lists() {

        // Group conditions are assumed to be 'permanent', so they affect the

        // display of user lists for activities.

        return true;

    }

    public function filter_user_list(array $users, $not, \core_availability\info $info,

            \core_availability\capability_checker $checker) {

        global $CFG, $DB;

        // If the array is empty already, just return it.

        if (!$users) {

            return $users;

        }

        require_once($CFG->libdir . '/grouplib.php');

        $course = $info->get_course();

        // List users for this course who match the condition.

        if ($this->groupid) {

            $groupusers = groups_get_members($this->groupid, 'u.id', 'u.id ASC');

        } else {

            $groupusers = $DB->get_records_sql("

                    SELECT DISTINCT gm.userid

                      FROM {groups} g

                      JOIN {groups_members} gm ON gm.groupid = g.id

                     WHERE g.courseid = ?", array($course->id));

        }

        // List users who have access all groups.

        $aagusers = $checker->get_users_by_capability('moodle/site:accessallgroups');

        // Filter the user list.

        $result = array();

        foreach ($users as $id => $user) {

            // Always include users with access all groups.

            if (array_key_exists($id, $aagusers)) {

                $result[$id] = $user;

                continue;

            }

            // Other users are included or not based on group membership.

            $allow = array_key_exists($id, $groupusers);

            if ($not) {

                $allow = !$allow;

            }

            if ($allow) {

                $result[$id] = $user;

            }

        }

        return $result;

    }

    /**

     * Returns a JSON object which corresponds to a condition of this type.

     *

     * Intended for unit testing, as normally the JSON values are constructed

     * by JavaScript code.

     *

     * @param int $groupid Required group id (0 = any group)

     * @return stdClass Object representing condition

     */

    public static function get_json($groupid = 0) {

        $result = (object)array('type' => 'group');

        // Id is only included if set.

        if ($groupid) {

            $result->id = (int)$groupid;

        }

        return $result;

    }

    public function get_user_list_sql($not, \core_availability\info $info, $onlyactive) {

        global $DB;

        // Get enrolled users with access all groups. These always are allowed.

        list($aagsql, $aagparams) = get_enrolled_sql(

                $info->get_context(), 'moodle/site:accessallgroups', 0, $onlyactive);

        // Get all enrolled users.

        list ($enrolsql, $enrolparams) =

                get_enrolled_sql($info->get_context(), '', 0, $onlyactive);

        // Condition for specified or any group.

        $matchparams = array();

        if ($this->groupid) {

            $matchsql = "SELECT 1

                           FROM {groups_members} gm

                          WHERE gm.userid = userids.id

                                AND gm.groupid = " .

                    self::unique_sql_parameter($matchparams, $this->groupid);

        } else {

            $matchsql = "SELECT 1

                           FROM {groups_members} gm

                           JOIN {groups} g ON g.id = gm.groupid

                          WHERE gm.userid = userids.id

                                AND g.courseid = " .

                    self::unique_sql_parameter($matchparams, $info->get_course()->id);

        }

        // Overall query combines all this.

        $condition = $not ? 'NOT' : '';

        $sql = "SELECT userids.id

                  FROM ($enrolsql) userids

                 WHERE (userids.id IN ($aagsql)) OR $condition EXISTS ($matchsql)";

        return array($sql, array_merge($enrolparams, $aagparams, $matchparams));

    }

}