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/>.

/**

 * This file contains components used by the restore UI

 *

 * @package   core_backup

 * @copyright 2010 Sam Hemelryk

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

 */

/**

 * A base class that can be used to build a specific search upon

 *

 * @package   core_backup

 * @copyright 2010 Sam Hemelryk

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

 */

abstract class restore_search_base implements renderable {

    /**

     * The default values for this components params

     */

    const DEFAULT_SEARCH = '';

    /**

     * The param used to convey the current search string

     * @var string

     */

    static $VAR_SEARCH = 'search';

    /**

     * The current search string

     * @var string|null

     */

    private $search = null;

    /**

     * The URL for this page including required params to return to it

     * @var moodle_url

     */

    private $url = null;

    /**

     * The results of the search

     * @var array|null

     */

    private $results = null;

    /**

     * The total number of results available

     * @var int

     */

    private $totalcount = null;

    /**

     * Array of capabilities required for each item in the search

     * @var array

     */

    private $requiredcapabilities = array();

    /**

     * Max number of courses to return in a search.

     * @var int

     */

    private $maxresults = null;

    /**

     * Indicates if we have more than maxresults found.

     * @var boolean

     */

    private $hasmoreresults = false;

    /**

     * Constructor

     * @param array $config Config options

     */

    public function __construct(array $config = array()) {

        $this->search = optional_param($this->get_varsearch(), self::DEFAULT_SEARCH, PARAM_NOTAGS);

        $this->search = trim($this->search);

        $this->maxresults = get_config('backup', 'import_general_maxresults');

        foreach ($config as $name => $value) {

            $method = 'set_'.$name;

            if (method_exists($this, $method)) {

                $this->$method($value);

            }

        }

    }

    /**

     * The URL for this search

     * @global moodle_page $PAGE

     * @return moodle_url The URL for this page

     */

    final public function get_url() {

        global $PAGE;

        $params = array(

            $this->get_varsearch()    => $this->get_search()

        );

        return ($this->url !== null) ? new moodle_url($this->url, $params) : new moodle_url($PAGE->url, $params);

    }

    /**

     * The current search string

     * @return string

     */

    final public function get_search() {

        return ($this->search !== null) ? $this->search : self::DEFAULT_SEARCH;

    }

    /**

     * The total number of results

     * @return int

     */

    final public function get_count() {

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

            $this->search();

        }

        return $this->totalcount;

    }

    /**

     * Returns an array of results from the search

     * @return array

     */

    final public function get_results() {

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

            $this->search();

        }

        return $this->results;

    }

    /**

     * Sets the page URL

     * @param moodle_url $url

     */

    final public function set_url(moodle_url $url) {

        $this->url = $url;

    }

    /**

     * Invalidates the results collected so far

     */

    final public function invalidate_results() {

        $this->results = null;

        $this->totalcount = null;

    }

    /**

     * Adds a required capability which all results will be checked against

     * @param string $capability

     * @param int|null $user

     */

    final public function require_capability($capability, $user = null) {

        if (!is_int($user)) {

            $user = null;

        }

        $this->requiredcapabilities[] = array(

            'capability' => $capability,

            'user' => $user

        );

    }

    /**

     * Executes the search

     *

     * @global moodle_database $DB

     * @return int The number of results

     */

    final public function search() {

        global $DB;

        if (!is_null($this->results)) {

            return $this->results;

        }

        $this->results = array();

        $this->totalcount = 0;

        $contextlevel = $this->get_itemcontextlevel();

        list($sql, $params) = $this->get_searchsql();

        // Get total number, to avoid some incorrect iterations.

        $countsql = preg_replace('/ORDER BY.*/', '', $sql);

        $totalcourses = $DB->count_records_sql("SELECT COUNT(*) FROM ($countsql) sel", $params);

        if ($totalcourses > 0) {

            // User to be checked is always the same (usually null, get it from first element).

            $firstcap = reset($this->requiredcapabilities);

            $userid = isset($firstcap['user']) ? $firstcap['user'] : null;

            // Extract caps to check, this saves us a bunch of iterations.

            $requiredcaps = array();

            foreach ($this->requiredcapabilities as $cap) {

                $requiredcaps[] = $cap['capability'];

            }

            // Iterate while we have records and haven't reached $this->maxresults.

            $resultset = $DB->get_recordset_sql($sql, $params);

            foreach ($resultset as $result) {

                context_helper::preload_from_record($result);

                $classname = context_helper::get_class_for_level($contextlevel);

                $context = $classname::instance($result->id);

                if (count($requiredcaps) > 0) {

                    if (!has_all_capabilities($requiredcaps, $context, $userid)) {

                        continue;

                    }

                }

                // Check if we are over the limit.

                if ($this->totalcount + 1 > $this->maxresults) {

                    $this->hasmoreresults = true;

                    break;

                }

                // If not, then continue.

                $this->totalcount++;

                $this->results[$result->id] = $result;

            }

            $resultset->close();

        }

        return $this->totalcount;

    }

    /**

     * Returns true if there are more search results.

     * @return bool

     */

    final public function has_more_results() {

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

            $this->search();

        }

        return $this->hasmoreresults;

    }

    /**

     * Returns an array containing the SQL for the search and the params

     * @return array

     */

    abstract protected function get_searchsql();

    /**

     * Gets the context level associated with this components items

     * @return CONTEXT_*

     */

    abstract protected function get_itemcontextlevel();

    /**

     * Formats the results

     */

    abstract protected function format_results();

    /**

     * Gets the string used to transfer the search string for this compontents requests

     * @return string

     */

    abstract public function get_varsearch();

}

/**

 * A course search component

 *

 * @package   core_backup

 * @copyright 2010 Sam Hemelryk

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

 */

class restore_course_search extends restore_search_base {

    /**

     * @var string

     */

    static $VAR_SEARCH = 'search';

    /**

     * The current course id.

     * @var int

     */

    protected $currentcourseid = null;

    /**

     * Determines if the current course is included in the results.

     * @var bool

     */

    protected $includecurrentcourse;

    /**

     * Constructor

     * @param array $config

     * @param int $currentcouseid The current course id so it can be ignored

     */

    public function __construct(array $config = array(), $currentcouseid = null) {

        parent::__construct($config);

        $this->setup_restrictions();

        $this->currentcourseid = $currentcouseid;

        $this->includecurrentcourse = false;

    }

    /**

     * Sets up any access restrictions for the courses to be displayed in the search.

     *

     * This will typically call $this->require_capability().

     */

    protected function setup_restrictions() {

        $this->require_capability('moodle/restore:restorecourse');

    }

    /**

     * Get the search SQL.

     * @global moodle_database $DB

     * @return array

     */

    protected function get_searchsql() {

        global $DB;

        $ctxselect = ', ' . context_helper::get_preload_record_columns_sql('ctx');

        $ctxjoin = "LEFT JOIN {context} ctx ON (ctx.instanceid = c.id AND ctx.contextlevel = :contextlevel)";

        $params = array(

            'contextlevel' => CONTEXT_COURSE,

            'fullnamesearch' => '%'.$this->get_search().'%',

            'shortnamesearch' => '%'.$this->get_search().'%'

        );

        $select     = " SELECT c.id, c.fullname, c.shortname, c.visible, c.sortorder ";

        $from       = " FROM {course} c ";

        $where      = " WHERE (".$DB->sql_like('c.fullname', ':fullnamesearch', false)." OR ".

            $DB->sql_like('c.shortname', ':shortnamesearch', false).")";

        $orderby    = " ORDER BY c.sortorder";

        if ($this->currentcourseid !== null && !$this->includecurrentcourse) {

            $where .= " AND c.id <> :currentcourseid";

            $params['currentcourseid'] = $this->currentcourseid;

        }

        return array($select.$ctxselect.$from.$ctxjoin.$where.$orderby, $params);

    }

    /**

     * Gets the context level for the search result items.

     * @return CONTEXT_|int

     */

    protected function get_itemcontextlevel() {

        return CONTEXT_COURSE;

    }

    /**

     * Formats results.

     */

    protected function format_results() {}

    /**

     * Returns the name the search variable should use

     * @return string

     */

    public function get_varsearch() {

        return self::$VAR_SEARCH;

    }

    /**

     * Returns true if the current course should be included in the results.

     */

    public function set_include_currentcourse() {

        $this->includecurrentcourse = true;

    }

    /**

     * Get the current course id

     *

     * @return int

     */

    public function get_current_course_id(): int {

        return $this->currentcourseid;

    }

}

/**

 * A category search component

 *

 * @package   core_backup

 * @copyright 2010 Sam Hemelryk

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

 */

class restore_category_search extends restore_search_base  {

    /**

     * The search variable to use.

     * @var string

     */

    static $VAR_SEARCH = 'catsearch';

    /**

     * Constructor

     * @param array $config

     */

    public function __construct(array $config = array()) {

        parent::__construct($config);

        $this->require_capability('moodle/course:create');

    }

    /**

     * Returns the search SQL.

     * @global moodle_database $DB

     * @return array

     */

    protected function get_searchsql() {

        global $DB;

        $ctxselect = ', ' . context_helper::get_preload_record_columns_sql('ctx');

        $ctxjoin = "LEFT JOIN {context} ctx ON (ctx.instanceid = c.id AND ctx.contextlevel = :contextlevel)";

        $params = array(

            'contextlevel' => CONTEXT_COURSECAT,

            'namesearch' => '%'.$this->get_search().'%',

        );

        $select     = " SELECT c.id, c.name, c.visible, c.sortorder, c.description, c.descriptionformat ";

        $from       = " FROM {course_categories} c ";

        $where      = " WHERE ".$DB->sql_like('c.name', ':namesearch', false);

        $orderby    = " ORDER BY c.sortorder";

        return array($select.$ctxselect.$from.$ctxjoin.$where.$orderby, $params);

    }

    /**

     * Returns the context level of the search results.

     * @return CONTEXT_COURSECAT

     */

    protected function get_itemcontextlevel() {

        return CONTEXT_COURSECAT;

    }

    /**

     * Formats the results.

     */

    protected function format_results() {}

    /**

     * Returns the name to use for the search variable.

     * @return string

     */

    public function get_varsearch() {

        return self::$VAR_SEARCH;

    }

}