<?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/>.

/**
 * @package    tool
 * @subpackage xmldb
 * @copyright  2003 onwards Eloy Lafuente (stronk7) {@link http://stronk7.com}
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

/**
 * This class will create a new default field to be edited
 *
 * @package    tool
 * @subpackage xmldb
 * @copyright  2003 onwards Eloy Lafuente (stronk7) {@link http://stronk7.com}
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
class new_field extends XMLDBAction {

    /**
     * Init method, every subclass will have its own
     */
    function init() {
        parent::init();

        // Set own custom attributes

        // Get needed strings
        $this->loadStrings(array(
            // 'key' => 'module',
        ));
    }

    /**
     * Invoke method, every class will have its own
     * returns true/false on completion, setting both
     * errormsg and output as necessary
     */
    function invoke() {
        parent::invoke();

        $result = true;

        // Set own core attributes
        $this->does_generate = ACTION_NONE;
        //$this->does_generate = ACTION_GENERATE_HTML;

        // These are always here
        global $CFG, $XMLDB;

        // Do the job, setting result as needed
        // Get the dir containing the file
        $dirpath = required_param('dir', PARAM_PATH);
        $dirpath = $CFG->dirroot . $dirpath;

        // Get the correct dirs
        if (!empty($XMLDB->dbdirs)) {
            $dbdir =& $XMLDB->dbdirs[$dirpath];
        } else {
            return false;
        }
        if (!empty($XMLDB->editeddirs)) {
            $editeddir =& $XMLDB->editeddirs[$dirpath];
            $structure =& $editeddir->xml_file->getStructure();
        }

        $tableparam = required_param('table', PARAM_CLEAN);

        $table =& $structure->getTable($tableparam);

        // If the changeme field exists, just get it and continue
        $changeme_exists = false;
        if ($fields =& $table->getFields()) {
            if ($field =& $table->getField('changeme')) {
                $changeme_exists = true;
            }
        }
        if (!$changeme_exists) { // Lets create the field
            $field = new xmldb_field('changeme');
            $table->addField($field);

            // We have one new field, so the structure has changed
            $structure->setVersion(userdate(time(), '%Y%m%d', 99, false));
            $structure->setChanged(true);
        }

        // Launch postaction if exists (leave this here!)
        if ($this->getPostAction() && $result) {
            return $this->launch($this->getPostAction());
        }

        // Return ok if arrived here
        return $result;
    }
}