<?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/>.

/**
 * Theme Boost Union - Form element for color picker
 *
 * @package    theme_boost_union
 * @copyright  2023 bdecent GmbH <https://bdecent.de>
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

namespace theme_boost_union\formelement;

use MoodleQuickForm_text;
use renderer_base;

defined('MOODLE_INTERNAL') || die();

require_once('HTML/QuickForm/input.php');
require_once($CFG->dirroot . '/lib/form/templatable_form_element.php');
require_once($CFG->dirroot . '/lib/form/text.php');

/**
 * Form element for color picker
 *
 * @package   theme_boost_union
 * @copyright 2023 bdecent GmbH <https://bdecent.de>
 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
class colorpicker extends MoodleQuickForm_text implements \core\output\templatable {
    use \templatable_form_element {
        export_for_template as export_for_template_base;
    }

    /**
     * Constructor.
     *
     * @param string $elementname (optional) Name of the text field.
     * @param string $elementlabel (optional) Text field label.
     * @param string $attributes (optional) Either a typical HTML attribute string or an associative array.
     */
    public function __construct($elementname = null, $elementlabel = null, $attributes = null) {
        parent::__construct($elementname, $elementlabel, $attributes);
        $this->setType('text');

        // Add a CSS class for styling the color picker.
        $class = $this->getAttribute('class');
        if (empty($class)) {
            $class = '';
        }
        $this->updateAttributes(['class' => $class . ' theme_boost_union-form-colour-picker ']);
    }

    /**
     * Export for template.
     *
     * @param renderer_base $output
     * @return array|stdClass
     */
    public function export_for_template(renderer_base $output) {
        global $PAGE;

        // Compose template context for the mform element.
        $context = $this->export_for_template_base($output);

        // Build loading icon.
        $icon = new \core\output\pix_icon('i/loading', get_string('loading', 'admin'), 'moodle', ['class' => 'loadingicon']);
        $icondata = $icon->export_for_template($output);
        $iconoutput = $output->render_from_template('core/pix_icon', $icondata);

        // Get ID of the element.
        $id = $this->getAttribute('id');

        // Add JS to append the color picker div before the element and initiate the color picker utility method.
        $PAGE->requires->js_amd_inline("
            var element = document.getElementById('$id');
            var pickerDiv = document.createElement('div');
            pickerDiv.classList.add('admin_colourpicker', 'clearfix');
            pickerDiv.innerHTML = '$iconoutput'; // Add loading icon.
            element.parentNode.prepend(pickerDiv);
            element.parentNode.style.flexDirection = 'column'; // Helps to align the config text when
                                                               // theme_boost_union is not the active theme.

            // Init color picker utility.
            M.util.init_colour_picker(Y, '$id');
        ");

        return $context;
    }
}
