Elgg-Lorea-Hydra/views/default/input/date.php

<?php
/**
 * Elgg date input
 * Displays a text field with a popup date picker.
 *
 * The elgg.ui JavaScript library initializes the jQueryUI datepicker based
 * on the CSS class .elgg-input-date. It uses the ISO 8601 standard for date
 * representation: yyyy-mm-dd.
 *
 * Unix timestamps are supported by setting the 'timestamp' parameter to true.
 * The date is still displayed to the user in a text format but is submitted as
 * a unix timestamp in seconds.
 *
 * @uses $vars['value']     The current value, if any (as a unix timestamp)
 * @uses $vars['class']     Additional CSS class
 * @uses $vars['timestamp'] Store as a Unix timestamp in seconds. Default = false
 *                          Note: you cannot use an id with the timestamp option.
 */

$vars['class'] = (array) elgg_extract('class', $vars, []);
$vars['class'][] = 'elgg-input-date';

//@todo popup_calendar deprecated in 1.8.  Remove in 2.0
$vars['class'][] = 'popup_calendar';

$defaults = array(
	'value' => '',
	'disabled' => false,
	'timestamp' => false,
	'type' => 'text'
);

$vars = array_merge($defaults, $vars);

$timestamp = $vars['timestamp'];
unset($vars['timestamp']);

if ($timestamp) {
	echo elgg_view('input/hidden', ['name' => $vars['name'], 'value' => $vars['value']]);

	$vars['class'][] = 'elgg-input-timestamp';
	$vars['id'] = $vars['name'];
	unset($vars['name']);
}

// convert timestamps to text for display
if (is_numeric($vars['value'])) {
	$vars['value'] = gmdate('Y-m-d', $vars['value']);
}

echo elgg_format_element('input', $vars);

if (elgg_is_xhr()) {
	echo elgg_format_element('script', null, 'elgg.ui.initDatePicker();');
}