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/>.

/**

 * Content manager class

 *

 * @package    core_contentbank

 * @copyright  2020 Amaia Anabitarte <amaia@moodle.com>

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

 */

namespace core_contentbank;

use core_text;

use stored_file;

use stdClass;

use coding_exception;

use context;

use moodle_url;

use core\event\contentbank_content_updated;

/**

 * Content manager class

 *

 * @package    core_contentbank

 * @copyright  2020 Amaia Anabitarte <amaia@moodle.com>

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

 */

abstract class content {

    /**

     * @var int Visibility value. Public content is visible to all users with access to the content bank of the

     * appropriate context.

     */

    public const VISIBILITY_PUBLIC = 1;

    /**

     * @var int Visibility value. Unlisted content is only visible to the author and to users with

     * moodle/contentbank:viewunlistedcontent capability.

     */

    public const VISIBILITY_UNLISTED = 2;

    /** @var stdClass $content The content of the current instance. **/

    protected $content  = null;

    /**

     * Content bank constructor

     *

     * @param stdClass $record A contentbank_content record.

     * @throws coding_exception If content type is not right.

     */

    public function __construct(stdClass $record) {

        // Content type should exist and be linked to plugin classname.

        $classname = $record->contenttype.'\\content';

        if (get_class($this) != $classname) {

            throw new coding_exception(get_string('contenttypenotfound', 'error', $record->contenttype));

        }

        $typeclass = $record->contenttype.'\\contenttype';

        if (!class_exists($typeclass)) {

            throw new coding_exception(get_string('contenttypenotfound', 'error', $record->contenttype));

        }

        // A record with the id must exist in 'contentbank_content' table.

        // To improve performance, we are only checking the id is set, but no querying the database.

        if (!isset($record->id)) {

            throw new coding_exception(get_string('invalidcontentid', 'error'));

        }

        $this->content = $record;

    }

    /**

     * Returns $this->content.

     *

     * @return stdClass  $this->content.

     */

    public function get_content(): stdClass {

        return $this->content;

    }

    /**

     * Returns $this->content->contenttype.

     *

     * @return string  $this->content->contenttype.

     */

    public function get_content_type(): string {

        return $this->content->contenttype;

    }

    /**

     * Return the contenttype instance of this content.

     *

     * @return contenttype The content type instance

     */

    public function get_content_type_instance(): contenttype {

        $context = context::instance_by_id($this->content->contextid);

        $contenttypeclass = "\\{$this->content->contenttype}\\contenttype";

        return new $contenttypeclass($context);

    }

    /**

     * Returns $this->content->timemodified.

     *

     * @return int  $this->content->timemodified.

     */

    public function get_timemodified(): int {

        return $this->content->timemodified;

    }

    /**

     * Updates content_bank table with information in $this->content.

     *

     * @return boolean  True if the content has been succesfully updated. False otherwise.

     * @throws \coding_exception if not loaded.

     */

    public function update_content(): bool {

        global $USER, $DB;

        // A record with the id must exist in 'contentbank_content' table.

        // To improve performance, we are only checking the id is set, but no querying the database.

        if (!isset($this->content->id)) {

            throw new coding_exception(get_string('invalidcontentid', 'error'));

        }

        $this->content->usermodified = $USER->id;

        $this->content->timemodified = time();

        $result = $DB->update_record('contentbank_content', $this->content);

        if ($result) {

            // Trigger an event for updating this content.

            $event = contentbank_content_updated::create_from_record($this->content);

            $event->trigger();

        }

        return $result;

    }

    /**

     * Set a new name to the content.

     *

     * @param string $name  The name of the content.

     * @return bool  True if the content has been succesfully updated. False otherwise.

     * @throws \coding_exception if not loaded.

     */

    public function set_name(string $name): bool {

        $name = trim($name);

        if ($name === '') {

            return false;

        }

        // Clean name.

        $name = clean_param($name, PARAM_TEXT);

        if (core_text::strlen($name) > 255) {

            $name = core_text::substr($name, 0, 255);

        }

        $oldname = $this->content->name;

        $this->content->name = $name;

        $updated = $this->update_content();

        if (!$updated) {

            $this->content->name = $oldname;

        }

        return $updated;

    }

    /**

     * Returns the name of the content.

     *

     * @return string   The name of the content.

     */

    public function get_name(): string {

        return $this->content->name;

    }

    /**

     * Set a new contextid to the content.

     *

     * @param int $contextid  The new contextid of the content.

     * @return bool  True if the content has been succesfully updated. False otherwise.

     */

    public function set_contextid(int $contextid): bool {

        if ($this->content->contextid == $contextid) {

            return true;

        }

        $oldcontextid = $this->content->contextid;

        $this->content->contextid = $contextid;

        $updated = $this->update_content();

        if ($updated) {

            // Move files to new context

            $fs = get_file_storage();

            $fs->move_area_files_to_new_context($oldcontextid, $contextid, 'contentbank', 'public', $this->content->id);

        } else {

            $this->content->contextid = $oldcontextid;

        }

        return $updated;

    }

    /**

     * Returns the contextid of the content.

     *

     * @return int   The id of the content context.

     */

    public function get_contextid(): string {

        return $this->content->contextid;

    }

    /**

     * Returns the content ID.

     *

     * @return int   The content ID.

     */

    public function get_id(): int {

        return $this->content->id;

    }

    /**

     * Change the content instanceid value.

     *

     * @param int $instanceid    New instanceid for this content

     * @return boolean           True if the instanceid has been succesfully updated. False otherwise.

     */

    public function set_instanceid(int $instanceid): bool {

        $this->content->instanceid = $instanceid;

        return $this->update_content();

    }

    /**

     * Returns the $instanceid of this content.

     *

     * @return int   contentbank instanceid

     */

    public function get_instanceid(): int {

        return $this->content->instanceid;

    }

    /**

     * Change the content config values.

     *

     * @param string $configdata    New config information for this content

     * @return boolean              True if the configdata has been succesfully updated. False otherwise.

     */

    public function set_configdata(string $configdata): bool {

        $this->content->configdata = $configdata;

        return $this->update_content();

    }

    /**

     * Return the content config values.

     *

     * @return mixed   Config information for this content (json decoded)

     */

    public function get_configdata() {

        return $this->content->configdata;

    }

    /**

     * Sets a new content visibility and saves it to database.

     *

     * @param int $visibility Must be self::PUBLIC or self::UNLISTED

     * @return bool

     * @throws coding_exception

     */

    public function set_visibility(int $visibility): bool {

        if (!in_array($visibility, [self::VISIBILITY_PUBLIC, self::VISIBILITY_UNLISTED])) {

            return false;

        }

        $this->content->visibility = $visibility;

        return $this->update_content();

    }

    /**

     * Return true if the content may be shown to other users in the content bank.

     *

     * @return boolean

     */

    public function get_visibility(): int {

        return $this->content->visibility;

    }

    /**

     * Import a file as a valid content.

     *

     * By default, all content has a public file area to interact with the content bank

     * repository. This method should be overridden by contentypes which does not simply

     * upload to the public file area.

     *

     * If any, the method will return the final stored_file. This way it can be invoked

     * as parent::import_file in case any plugin want to store the file in the public area

     * and also parse it.

     *

     * @param stored_file $file File to store in the content file area.

     * @return stored_file|null the stored content file or null if the file is discarted.

     */

    public function import_file(stored_file $file): ?stored_file {

        $originalfile = $this->get_file();

        if ($originalfile) {

            $originalfile->replace_file_with($file);

            return $originalfile;

        } else {

            $fs = get_file_storage();

            $filerecord = [

                'contextid' => $this->get_contextid(),

                'component' => 'contentbank',

                'filearea' => 'public',

                'itemid' => $this->get_id(),

                'filepath' => '/',

                'filename' => $file->get_filename(),

                'timecreated' => time(),

            ];

            return $fs->create_file_from_storedfile($filerecord, $file);

        }

    }

    /**

     * Returns the $file related to this content.

     *

     * @return stored_file  File stored in content bank area related to the given itemid.

     * @throws \coding_exception if not loaded.

     */

    public function get_file(): ?stored_file {

        $itemid = $this->get_id();

        $fs = get_file_storage();

        $files = $fs->get_area_files(

            $this->content->contextid,

            'contentbank',

            'public',

            $itemid,

            'itemid, filepath, filename',

            false

        );

        if (!empty($files)) {

            $file = reset($files);

            return $file;

        }

        return null;

    }

    /**

     * Returns the places where the file associated to this content is used or an empty array if the content has no file.

     *

     * @return array of stored_file where current file content is used or empty array if it hasn't any file.

     * @since 3.11

     */

    public function get_uses(): ?array {

        $references = [];

        $file = $this->get_file();

        if ($file != null) {

            $fs = get_file_storage();

            $references = $fs->get_references_by_storedfile($file);

        }

        return $references;

    }

    /**

     * Returns the file url related to this content.

     *

     * @return string       URL of the file stored in content bank area related to the given itemid.

     * @throws \coding_exception if not loaded.

     */

    public function get_file_url(): string {

        if (!$file = $this->get_file()) {

            return '';

        }

        $fileurl = moodle_url::make_pluginfile_url(

            $this->content->contextid,

            'contentbank',

            'public',

            $file->get_itemid(),

            $file->get_filepath(),

            $file->get_filename()

        );

        return $fileurl;

    }

    /**

     * Returns user has access permission for the content itself (based on what plugin needs).

     *

     * @return bool     True if content could be accessed. False otherwise.

     */

    public function is_view_allowed(): bool {

        // Plugins can overwrite this method in case they want to check something related to content properties.

        global $USER;

        $context = \context::instance_by_id($this->get_contextid());

        return $USER->id == $this->content->usercreated ||

            $this->get_visibility() == self::VISIBILITY_PUBLIC ||

            has_capability('moodle/contentbank:viewunlistedcontent', $context);

    }

}