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 the backup user interface class

 *

 * @package   core_backup

 * @copyright 2010 Sam Hemelryk

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

 */

/**

 * This is the backup user interface class

 *

 * The backup user interface class manages the user interface and backup for

 * Moodle.

 *

 * @package   core_backup

 * @copyright 2010 Sam Hemelryk

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

 */

abstract class base_ui {

    /**

     * The progress of this instance of the backup ui class

     * It is in the initial stage.

     */

    const PROGRESS_INTIAL = 0;

    /**

     * The progress of this instance of the backup ui class

     * It is processed.

     */

    const PROGRESS_PROCESSED = 1;

    /**

     * The progress of this instance of the backup ui class

     * It is saved.

     */

    const PROGRESS_SAVED = 2;

    /**

     * The progress of this instance of the backup ui class

     * It has been executed.

     */

    const PROGRESS_EXECUTED = 3;

    /**

     * The controller

     * @var backup_controller|restore_controller

     */

    protected $controller;

    /**

     * The current stage

     * @var base_ui_stage

     */

    protected $stage;

    /**

     * The current progress of the UI

     * @var int One of self::PROGRESS_*

     */

    protected $progress;

    /**

     * The number of changes made by dependency enforcement

     * @var int

     */

    protected $dependencychanges = 0;

    /**

     * Yay for constructors

     * @param backup_controller $controller

     * @param array $params

     */

    public function __construct($controller, array $params = null) {

        $this->controller = $controller;

        $this->progress = self::PROGRESS_INTIAL;

        $this->stage = $this->initialise_stage(null, $params);

        if ($this->controller) {

            // Process UI event before to be safe.

            $this->controller->process_ui_event();

        }

    }

    /**

     * Destorys the backup controller and the loaded stage.

     */

    public function destroy() {

        if ($this->controller) {

            $this->controller->destroy();

        }

        unset($this->stage);

    }

    /**

     * Intialises what ever stage is requested. If none are requested we check

     * params for 'stage' and default to initial

     *

     * @param int|null $stage The desired stage to intialise or null for the default

     * @param array $params

     * @return base_ui_stage

     */

    abstract protected function initialise_stage($stage = null, array $params = null);

    /**

     * This processes the current stage of the backup

     * @throws backup_ui_exception

     * @return bool

     */

    public function process() {

        if ($this->progress >= self::PROGRESS_PROCESSED) {

            throw new backup_ui_exception('backupuialreadyprocessed');

        }

        $this->progress = self::PROGRESS_PROCESSED;

        if (optional_param('previous', false, PARAM_BOOL) && $this->stage->get_stage() > $this->get_first_stage_id()) {

            $this->stage = $this->initialise_stage($this->stage->get_prev_stage(), $this->stage->get_params());

            return false;

        }

        // Process the stage.

        $processoutcome = $this->stage->process();

        if ($processoutcome !== false) {

            $this->stage = $this->initialise_stage($this->stage->get_next_stage(), $this->stage->get_params());

        }

        // Process UI event after to check changes are valid.

        $this->controller->process_ui_event();

        return $processoutcome;

    }

    /**

     * Saves the backup controller.

     *

     * Once this has been called nothing else can be changed in the controller.

     *

     * @throws base_ui_exception

     * @return bool

     */

    public function save_controller() {

        if ($this->progress >= self::PROGRESS_SAVED) {

            throw new base_ui_exception('backupuialreadysaved');

        }

        $this->progress = self::PROGRESS_SAVED;

        // First enforce dependencies.

        $this->enforce_dependencies();

        // Process UI event after to check any changes are valid.

        $this->controller->process_ui_event();

        // Save the controller.

        $this->controller->save_controller();

        return true;

    }

    /**

     * Displays the UI for the backup!

     *

     * @throws base_ui_exception

     * @param core_backup_renderer $renderer

     * @return string HTML code to echo

     */

    public function display(core_backup_renderer $renderer) {

        if ($this->progress < self::PROGRESS_SAVED) {

            throw new base_ui_exception('backupsavebeforedisplay');

        }

        return $this->stage->display($renderer);

    }

    /**

     * Gets all backup tasks from the controller

     * @return array Array of backup_task

     */

    public function get_tasks() {

        $plan = $this->controller->get_plan();

        $tasks = $plan->get_tasks();

        return $tasks;

    }

    /**

     * Gets the stage we are on

     * @return int

     */

    public function get_stage() {

        return $this->stage->get_stage();

    }

    /**

     * Gets the name of the stage we are on

     * @return string

     */

    public function get_stage_name() {

        return $this->stage->get_name();

    }

    /**

     * Gets the backup id from the controller

     * @return string

     */

    abstract public function get_uniqueid();

    /**

     * Executes the backup plan

     * @return bool

     */

    abstract public function execute();

    /**

     * Enforces dependencies on all settings. Call before save

     * @return bool True if dependencies were enforced and changes were made

     */

    protected function enforce_dependencies() {

        // Get the plan.

        $plan = $this->controller->get_plan();

        // Get the tasks as a var so we can iterate by reference.

        $tasks = $plan->get_tasks();

        $changes = 0;

        foreach ($tasks as &$task) {

            // Store as a var so we can iterate by reference.

            $settings = $task->get_settings();

            foreach ($settings as &$setting) {

                // Get all dependencies for iteration by reference.

                $dependencies = $setting->get_dependencies();

                foreach ($dependencies as &$dependency) {

                    // Enforce each dependency.

                    if ($dependency->enforce()) {

                        $changes++;

                    }

                }

            }

        }

        // Store the number of settings that changed through enforcement.

        $this->dependencychanges = $changes;

        return ($changes > 0);

    }

    /**

     * Returns true if enforce_dependencies changed any settings

     * @return bool

     */

    public function enforce_changed_dependencies() {

        return ($this->dependencychanges > 0);

    }

    /**

     * Loads the backup controller if we are tracking one

     * @throws coding_exception

     * @param string|bool $uniqueid

     * @return backup_controller|false

     */

    public static function load_controller($uniqueid = false) {

        throw new coding_exception('load_controller() method needs to be overridden in each subclass of base_ui');

    }

    /**

     * Cancels the current backup/restore and redirects the user back to the relevant place

     */

    public function cancel_process() {

        global $PAGE;

        // Determine the appropriate URL to redirect the user to.

        if ($PAGE->context->contextlevel == CONTEXT_MODULE && $PAGE->cm !== null) {

            $relevanturl = new moodle_url('/mod/'.$PAGE->cm->modname.'/view.php', array('id' => $PAGE->cm->id));

        } else {

            $relevanturl = new moodle_url('/course/view.php', array('id' => $PAGE->course->id));

        }

        redirect($relevanturl);

    }

    /**

     * Gets an array of progress bar items that can be displayed through the backup renderer.

     * @return array Array of items for the progress bar

     */

    abstract public function get_progress_bar();

    /**

     * Gets the format for the backup

     * @return int

     */

    public function get_format() {

        return $this->controller->get_format();

    }

    /**

     * Gets the type of the backup

     * @return int

     */

    public function get_type() {

        return $this->controller->get_type();

    }

    /**

     * Returns the controller object.

     * @return backup_controller|restore_controller

     */

    public function get_controller() {

        return $this->controller;

    }

    /**

     * Gets the ID used in creating the controller. Relates to course/section/cm

     * @return int

     */

    public function get_controller_id() {

        return $this->controller->get_id();

    }

    /**

     * Gets the requested setting

     * @param string $name

     * @param bool $default

     * @return base_setting

     */

    public function get_setting($name, $default = false) {

        try {

            return $this->controller->get_plan()->get_setting($name);

        } catch (Exception $e) {

            debugging('Failed to find the setting: '.$name, DEBUG_DEVELOPER);

            return $default;

        }

    }

    /**

     * Gets the value for the requested setting

     *

     * @param string $name

     * @param bool $default

     * @return mixed

     */

    public function get_setting_value($name, $default = false) {

        try {

            return $this->controller->get_plan()->get_setting($name)->get_value();

        } catch (Exception $e) {

            debugging('Failed to find the setting: '.$name, DEBUG_DEVELOPER);

            return $default;

        }

    }

    /**

     * Returns the name of this stage.

     * @return mixed

     */

    abstract public function get_name();

    /**

     * Returns the first stage ID.

     * @return mixed

     */

    abstract public function get_first_stage_id();

}

/**

 * Backup user interface exception. Modelled off the backup_exception class

 *

 * @package   core_backup

 * @copyright 2010 Sam Hemelryk

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

 */

class base_ui_exception extends backup_exception {}