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/>.

namespace tool_brickfield\local\tool;

use tool_brickfield\accessibility;

use tool_brickfield\manager;

/**

 * Class filter.

 *

 * @package tool_brickfield

 * @copyright  2020 onward: Brickfield Education Labs, www.brickfield.ie

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

 */

class filter {

    /** @var int Possible course id being filtered. */

    public $courseid;

    /** @var int Possible category id being filtered. */

    public $categoryid;

    /** @var string The tab (page) being accessed. */

    public $tab;

    /** @var int The page number if multiple pages. */

    public $page;

    /** @var int Number of items per page for multiple pages. */

    public $perpage;

    /** @var array Array of filtered course ids if more than one. */

    public $courseids;

    /** @var string The url of the page being accessed. */

    public $url;

    /** @var string The output target. */

    public $target;

    /** @var string Any error message if present. */

    protected $errormessage;

    /**

     * filter constructor.

     * @param int $courseid

     * @param int $categoryid

     * @param string $tab

     * @param int $page

     * @param int $perpage

     * @param string $url

     * @param string $target

     */

    public function __construct(int $courseid = 0, int $categoryid = 0, string $tab = '',

                                int $page = 0, int $perpage = 0, string $url = '', string $target = '') {

        $this->courseid = $courseid;

        $this->categoryid = $categoryid;

        $this->tab = $tab;

        $this->page = $page;

        $this->perpage = $perpage;

        $this->url = $url;

        $this->target = $target;

    }

    /**

     * Get any course and category sql fragment and parameters and return as an array for this filter. Return false if course

     * filters are invalid.

     * @param string $alias Optional field alias to prefix on the where condition.

     * @param bool $onlycondition Set to true if this is the only condition to be used in the SQL statement.

     * @return array|bool

     * @throws \coding_exception

     * @throws \dml_exception

     */

    public function get_course_sql(string $alias = '', bool $onlycondition = false) {

        global $DB;

        $params = [];

        if ($alias != '') {

            $alias .= '.';

        }

        if (!$onlycondition) {

            $sql = ' AND (';

        } else {

            $sql = '(';

        }

        if ($this->courseid != 0) {

            $sql .= $alias . 'courseid = ?)';

            $params[] = $this->courseid;

        } else if (($this->categoryid != 0) || !empty($this->courseids)) {

            if ($this->validate_filters()) {

                list($coursesql, $params) = $DB->get_in_or_equal($this->courseids);

                $sql .= $alias . 'courseid '.$coursesql . ')';

            } else {

                $sql = '';

            }

        } else {

            $sql = '';

        }

        return [$sql, $params];

    }

    /**

     * Validate the filters. Set an errormessage if invalid. No filters is also valid - in that case using entire system.

     * @return bool

     * @throws \coding_exception

     * @throws \dml_exception

     */

    public function validate_filters(): bool {

        if (!empty($this->courseid)) {

            return true;

        } else if (!empty($this->categoryid) && empty($this->courseids)) {

            $this->courseids = accessibility::get_category_courseids($this->categoryid);

            if ($this->courseids === null) {

                $this->errormessage = get_string('invalidcategoryid', manager::PLUGINNAME);

                return false;

            } else if (count($this->courseids) == 0) {

                $this->errormessage = get_string('emptycategory', manager::PLUGINNAME, $this->categoryid);

                return false;

            }

        }

        return true;

    }

    /**

     * Return true if filter has course filter data, and the data is valid. Note that the site uses courseid 1.

     * @return bool

     * @throws \coding_exception

     * @throws \dml_exception

     */

    public function has_course_filters(): bool {

        if ((!empty($this->courseid) && ($this->courseid > 1)) || !empty($this->categoryid) || !empty($this->courseids)) {

            return $this->validate_filters();

        }

        return false;

    }

    /**

     * Check whether the user has appropriate permissions on the supplied context. Determine the capability to check by the filters

     * that are set.

     * @param \context|null $context The context being viewed (e.g. system, course category, course).

     * @param string $capability An optional capability to check.

     * @return bool

     * @throws \coding_exception

     * @throws \dml_exception

     */

    public function can_access(\context $context = null, string $capability = ''): bool {

        if ($capability == '') {

            if ($this->has_course_filters()) {

                $capability = accessibility::get_capability_name('viewcoursetools');

            } else {

                $capability = accessibility::get_capability_name('viewsystemtools');

            }

        }

        return $this->has_capability_in_context($capability, $context);

    }

    /**

     * Check the specified capability against the filter's context, or the specified context with the filter's information.

     * @param string $capability

     * @param null $context

     * @return bool

     * @throws \coding_exception

     * @throws \dml_exception

     */

    public function has_capability_in_context(string $capability, \context $context = null): bool {

        $coursefiltersvalid = $this->has_course_filters();

        if ($context === null) {

            // If the filter is using a list of courses ($this->>courseids), use the system context.

            if ($coursefiltersvalid && !empty($this->courseid)) {

                if (!empty($this->categoryid)) {

                    $context = \context_coursecat::instance($this->categoryid);

                } else {

                    $context = \context_course::instance($this->courseid);

                }

            } else {

                $context = \context_system::instance();

            }

        }

        return has_capability($capability, $context);

    }

    /**

     * Return the error message data.

     * @return mixed

     */

    public function get_errormessage() {

        return $this->errormessage;

    }

}