cs_date_formatter.module

<?php
/**
 * @file
 * Client Side Date Formatter main code.
 */

/**
 * Implements hook_field_formatter_info().
 */
function cs_date_formatter_field_formatter_info() {
  $formats = array(
    'cs_date_format' => array(
      'label' => t('Client side formatted'),
      'field types' => array(
        // These ship with the Date module.
        'date',
        'datestamp',
        'datetime',
      ),
      // @see https://reference.codeproject.com/Book/javascript/reference/global_objects/datetimeformat
      'settings' => array(
        'date_format' => 'simple',
        'weekday' => 'hidden',
        'year' => 'numeric',
        'month' => 'short',
        'day' => '2-digit',
        'hour' => '2-digit',
        'minute' => '2-digit',
        'second' => 'hidden',
        'timezonename' => 'short',
      ),
    ),
  );
  return $formats;
}

/**
 * Implements hook_field_formatter_settings_form().
 */
function cs_date_formatter_field_formatter_settings_form($field, $instance, $view_mode, $form, &$form_state) {
  $display = $instance['display'][$view_mode];
  $settings = $display['settings'];
  $element = array();

  $element['date_format'] = array(
    '#title' => t('Format'),
    '#type' => 'radios',
    '#default_value' => isset($settings['date_format']) ? $settings['date_format'] : 'simple',
    '#options' => array(
      'simple' => t('Simple'),
      'extended' => t('Extended'),
    ),
  );

  // Consider we're on a views admin form, which uses different attributes than
  // the regular field UI admin form.
  $args = arg();
  if (isset($args[2]) && $args[2] == 'views') {
    $name_attribute = 'options[settings][date_format]';
  }
  else {
    $name_attribute = 'fields[' . $field['field_name'] . '][settings_edit_form][settings][date_format]';
  }
  $states = array(
    'invisible' => array(
      ':input[name="' . $name_attribute . '"]' => array('value' => 'simple'),
    ),
    'disabled' => array(
      ':input[name="' . $name_attribute . '"]' => array('value' => 'simple'),
    ),
  );
  $element_commons = array(
    '#states' => $states,
    '#wrapper_attributes' => array(
      'class' => array('cs-date-formatter-row'),
    ),
  );

  $options = array(
    'hidden' => t('Hidden'),
  );
  $options_n2d = array(
    'numeric' => t('Numeric'),
    '2-digit' => t('Two digits'),
  );
  $options_nsl = array(
    'narrow' => t('Narrow'),
    'short' => t('Short'),
    'long' => t('Long'),
  );
  $options_sl = array_slice($options_nsl, 1);
  $options_num_types = array_merge($options, $options_n2d);

  $element['weekday'] = array(
    '#type' => 'select',
    '#title' => t('Weekday display'),
    '#options' => array_merge($options, $options_nsl),
    '#default_value' => $settings['weekday'],
  ) + $element_commons;
  $element['year'] = array(
    '#type' => 'select',
    '#title' => t('Year display'),
    '#options' => $options_num_types,
    '#default_value' => $settings['year'],
  ) + $element_commons;
  $element['month'] = array(
    '#type' => 'select',
    '#title' => t('Month display'),
    '#options' => array_merge($options, $options_n2d, $options_nsl),
    '#default_value' => $settings['month'],
  ) + $element_commons;
  $element['day'] = array(
    '#type' => 'select',
    '#title' => t('Day display'),
    '#options' => $options_num_types,
    '#default_value' => $settings['day'],
  ) + $element_commons;
  $element['hour'] = array(
    '#type' => 'select',
    '#title' => t('Hour display'),
    '#options' => $options_num_types,
    '#default_value' => $settings['hour'],
  ) + $element_commons;
  $element['minute'] = array(
    '#type' => 'select',
    '#title' => t('Minute display'),
    '#options' => $options_num_types,
    '#default_value' => $settings['minute'],
  ) + $element_commons;
  $element['second'] = array(
    '#type' => 'select',
    '#title' => t('Seconds display'),
    '#options' => $options_num_types,
    '#default_value' => $settings['second'],
  ) + $element_commons;
  $element['timezonename'] = array(
    '#type' => 'select',
    '#title' => t('Timezone name display'),
    '#options' => array_merge($options, $options_sl),
    '#default_value' => $settings['timezonename'],
  ) + $element_commons;

  $element['#attached']['css'] = array(
    backdrop_get_path('module', 'cs_date_formatter') . '/css/cs-date-formatter-admin.css',
  );

  return $element;
}

/**
 * Implements hook_field_formatter_settings_summary().
 */
function cs_date_formatter_field_formatter_settings_summary($field, $instance, $view_mode) {
  $display = $instance['display'][$view_mode];
  $settings = $display['settings'];
  $summary = '<p>' . t('Let the browser render the date (requires Javascript)') . '</p>';

  if ($settings['date_format'] == 'extended') {
    $list = array();
    foreach ($settings as $key => $value) {
      if ($value != 'hidden') {
        $list[] = $key . ': ' . $value;
      }
    }
    $summary .= theme('item_list', array('items' => $list));
  }
  else {
    $summary .= theme('item_list', array('items' => array('date_format: simple')));
  }
  return $summary;
}

/**
 * Implements hook_field_display_alter().
 *
 * Hand over the view_mode to cs_date_formatter_field_formatter_view().
 */
function cs_date_formatter_field_display_alter(&$display, $context) {
  if ($display['type'] == 'cs_date_format') {
    $display['view_mode'] = $context['view_mode'];
  }
}

/**
 * Implements hook_field_formatter_view().
 */
function cs_date_formatter_field_formatter_view($entity_type, $entity, $field, $instance, $langcode, $items, $display) {
  $element = array();

  if ($display['type'] == 'cs_date_format') {
    $settings = $display['settings'];
    $view_mode = '';
    if (isset($display['view_mode'])) {
      $view_mode = $display['view_mode'];
    }
    elseif (isset($display['views_view'])) {
      $view_mode = $display['views_view']->name;
    }
    foreach ($items as $delta => $item) {
      $element[$delta] = array(
        '#theme' => 'cs_date_formatter_default',
        '#element' => $item,
        '#field' => $instance,
        '#view_mode' => $view_mode,
      );

      // Attach our Javascript and settings.
      $element[$delta]['#attached']['js'][] = array(
        'data' => backdrop_get_path('module', 'cs_date_formatter') . '/js/cs-date-formatter.js',
        'type' => 'file',
      );
      $js_settings = array();
      if ($settings['date_format'] == 'extended') {
        $js_settings['date_format'] = 'extended';
        $js_settings['extended'] = array_filter($settings, function($value) {
          return ($value != 'hidden' && $value != 'extended');
        });
        if (isset($js_settings['extended']['timezonename'])) {
          // Switch to camel case.
          $js_settings['extended']['timeZoneName'] = $js_settings['extended']['timezonename'];
          unset($js_settings['extended']['timezonename']);
        }
      }
      else {
        $js_settings['date_format'] = 'simple';
        $js_settings['extended'] = array();
      }
      $setting_name = $field['field_name'] . '-' . $view_mode;
      $element[$delta]['#attached']['js'][] = array(
        'data' => array(
          'csDateFormatter' => array($setting_name => $js_settings),
        ),
        'type' => 'setting',
      );
    }
  }

  return $element;
}

/**
 * Implements hook_theme().
 */
function cs_date_formatter_theme($existing, $type, $theme, $path) {
  return array(
    'cs_date_formatter_default' => array(
      'variables' => array(
        'element' => NULL,
        'field' => NULL,
        'view_mode' => NULL,
      ),
    ),
  );
}

/**
 * Custom theme function.
 */
function theme_cs_date_formatter_default($variables) {
  $values = _cs_date_formatter_get_timestamp($variables['element']);
  $tags = array();

  $setting_name = $variables['field']['field_name'];
  if (!empty($variables['view_mode'])) {
    $setting_name .= '-' . $variables['view_mode'];
  }
  foreach ($values as $key => $value) {
    // Javascript will parse the date_string.
    $date_string = format_date($value, 'html_datetime');
    $attributes = array(
      'datetime' => $date_string,
      'class' => array('cs-date-format'),
      'data-cs-setting-name' => $setting_name,
    );
    $tags[] = '<time ' . backdrop_attributes($attributes) . '>' . $date_string . '</time>';
  }
  $markup = implode(' - ', $tags);

  return $markup;
}

/**
 * Custom helper function to convert different date formats to timestamp.
 *
 * @param array $element
 *   Associative array of date field values.
 *
 * @return array
 *   Array with start and possibly end as timestamps.
 */
function _cs_date_formatter_get_timestamp($element) {
  $values = array();
  switch ($element['date_type']) {
    case 'datestamp':
      $values['start'] = $element['value'];
      if (isset($element['value2'])) {
        $values['end'] = $element['value2'];
      }
      break;

    default:
      $date = new BackdropDateTime($element['value'], $element['timezone_db']);
      $values['start'] = $date->format('U');
      if (isset($element['value2'])) {
        $date_end = new BackdropDateTime($element['value2'], $element['timezone_db']);
        $values['end'] = $date->format('U');
      }
      break;

  }
  return $values;
}