- Patch #11623 by sun, stella, Gábor Hojtsy, Pancho: add ability to localize date formats.

6 files changed, 1187 insertions, 118 deletions

diff --git a/modules/system/system.admin.inc b/modules/system/system.admin.inc
index 190128b4a..dbc02b607 100644
--- a/modules/system/system.admin.inc
+++ b/modules/system/system.admin.inc
@@ -1592,16 +1592,13 @@ function system_rss_feeds_settings() {
 }
 
 /**
- * Form builder; Configure the site date and time settings.
+ * Form builder; Configure the site regional settings.
  *
  * @ingroup forms
  * @see system_settings_form()
  * @see system_regional_settings_submit()
  */
 function system_regional_settings() {
-  drupal_add_js(drupal_get_path('module', 'system') . '/system.js');
-  drupal_add_js(array('dateTime' => array('lookup' => url('admin/config/regional/settings/lookup'))), 'setting');
-
   include_once DRUPAL_ROOT . '/includes/locale.inc';
   $countries = country_get_list();
   // Add a 'No default country' option to the start of the list.
@@ -1610,31 +1607,6 @@ function system_regional_settings() {
   // Date settings:
   $zones = system_time_zones();
 
-  // Date settings: possible date formats
-  $date_short = array('Y-m-d H:i', 'm/d/Y - H:i', 'd/m/Y - H:i', 'Y/m/d - H:i',
-           'd.m.Y - H:i', 'm/d/Y - g:ia', 'd/m/Y - g:ia', 'Y/m/d - g:ia',
-           'M j Y - H:i', 'j M Y - H:i', 'Y M j - H:i',
-           'M j Y - g:ia', 'j M Y - g:ia', 'Y M j - g:ia');
-  $date_medium = array('D, Y-m-d H:i', 'D, m/d/Y - H:i', 'D, d/m/Y - H:i',
-          'D, Y/m/d - H:i', 'F j, Y - H:i', 'j F, Y - H:i', 'Y, F j - H:i',
-          'D, m/d/Y - g:ia', 'D, d/m/Y - g:ia', 'D, Y/m/d - g:ia',
-          'F j, Y - g:ia', 'j F Y - g:ia', 'Y, F j - g:ia', 'j. F Y - G:i');
-  $date_long = array('l, F j, Y - H:i', 'l, j F, Y - H:i', 'l, Y, F j - H:i',
-        'l, F j, Y - g:ia', 'l, j F Y - g:ia', 'l, Y, F j - g:ia', 'l, j. F Y - G:i');
-
-  // Date settings: construct choices for user
-  foreach ($date_short as $f) {
-    $date_short_choices[$f] = format_date(REQUEST_TIME, 'custom', $f);
-  }
-  foreach ($date_medium as $f) {
-    $date_medium_choices[$f] = format_date(REQUEST_TIME, 'custom', $f);
-  }
-  foreach ($date_long as $f) {
-    $date_long_choices[$f] = format_date(REQUEST_TIME, 'custom', $f);
-  }
-
-  $date_long_choices['custom'] = $date_medium_choices['custom'] = $date_short_choices['custom'] = t('Custom format');
-
   $form['locale'] = array(
     '#type' => 'fieldset',
     '#title' => t('Locale'),
@@ -1699,97 +1671,214 @@ function system_regional_settings() {
     '#description' => t('Only applied if users may set their own time zone.')
   );
 
-  $form['date_formats'] = array(
-    '#type' => 'fieldset',
-    '#title' => t('Date formats'),
-  );
+  return system_settings_form($form, FALSE);
+}
 
-  $date_format_short = variable_get('date_format_short', $date_short[1]);
-  $form['date_formats']['date_format_short'] = array(
-    '#prefix' => '<div class="date-container"><div class="select-container">',
-    '#suffix' => '</div>',
-    '#type' => 'select',
-    '#title' => t('Short date format'),
-    '#attributes' => array('class' => array('date-format')),
-    '#default_value' => (isset($date_short_choices[$date_format_short]) ? $date_format_short : 'custom'),
-    '#options' => $date_short_choices,
-  );
+/**
+ * Form builder; Configure the site date and time settings.
+ *
+ * @ingroup forms
+ * @see system_settings_form()
+ */
+function system_date_time_settings() {
+  // Get list of all available date types.
+  drupal_static_reset('system_get_date_types');
+  $format_types = system_get_date_types();
+
+  // Get list of all available date formats.
+  $all_formats = array();
+  drupal_static_reset('system_get_date_formats');
+  $date_formats = system_get_date_formats(); // Call this to rebuild the list, and to have default list.
+  foreach ($date_formats as $type => $format_info) {
+    $all_formats = array_merge($all_formats, $format_info);
+  }
+  $custom_formats = system_get_date_formats('custom');
+  if (!empty($format_types)) {
+    foreach ($format_types as $type => $type_info) {
+      // If a system type, only show the available formats for that type and
+      // custom ones.
+      if ($type_info['locked'] == 1) {
+        $formats = system_get_date_formats($type);
+        if (empty($formats)) {
+          $formats = $all_formats;
+        }
+        elseif (!empty($custom_formats)) {
+          $formats = array_merge($formats, $custom_formats);
+        }
+      }
+      // If a user configured type, show all available date formats.
+      else {
+        $formats = $all_formats;
+      }
 
-  $default_short_custom = variable_get('date_format_short_custom', (isset($date_short_choices[$date_format_short]) ? $date_format_short : ''));
-  $form['date_formats']['date_format_short_custom'] = array(
-    '#prefix' => '<div class="custom-container">',
-    '#suffix' => '</div></div>',
-    '#type' => 'textfield',
-    '#title' => t('Custom short date format'),
-    '#attributes' => array('class' => array('custom-format')),
-    '#default_value' => $default_short_custom,
-    '#description' => t('A user-defined short date format. See the <a href="@url">PHP manual</a> for available options. This format is currently set to display as <span>%date</span>.', array('@url' => 'http://php.net/manual/function.date.php', '%date' => format_date(REQUEST_TIME, 'custom', $default_short_custom))),
-  );
+      $choices = array();
+      foreach ($formats as $f => $format) {
+        $choices[$f] = format_date(REQUEST_TIME, 'custom', $f);
+      }
+      $default = variable_get('date_format_' . $type, array_shift(array_keys($formats)));
+
+      // Get date type info for this date type.
+      $type_info = system_get_date_types($type);
+      $form['formats']['#theme'] = 'system_date_time_settings';
+
+      // Show date format select list.
+      $form['formats']['format']['date_format_' . $type] = array(
+        '#type' => 'select',
+        '#title' => check_plain($type_info['title']),
+        '#attributes' => array('class' => array('date-format')),
+        '#default_value' => (isset($choices[$default]) ? $default : 'custom'),
+        '#options' => $choices,
+      );
 
-  $date_format_medium = variable_get('date_format_medium', $date_medium[1]);
-  $form['date_formats']['date_format_medium'] = array(
-    '#prefix' => '<div class="date-container"><div class="select-container">',
-    '#suffix' => '</div>',
-    '#type' => 'select',
-    '#title' => t('Medium date format'),
-    '#attributes' => array('class' => array('date-format')),
-    '#default_value' => (isset($date_medium_choices[$date_format_medium]) ? $date_format_medium : 'custom'),
-    '#options' => $date_medium_choices,
+      // If this isn't a system provided type, allow the user to remove it from
+      // the system.
+      if ($type_info['locked'] == 0) {
+        $form['formats']['delete']['date_format_' . $type . '_delete'] = array(
+          '#markup' => l(t('delete'), 'admin/config/regional/date-time/types/' . $type . '/delete'),
+        );
+      }
+    }
+  }
+
+  // Display a message if no date types configured.
+  $form['#empty_text'] = t('No date types available. <a href="@link">Add date type</a>.', array('@link' => url('admin/config/regional/date-time/types/add')));
+
+  return system_settings_form($form, FALSE);
+}
+
+/**
+ * Theme function for date settings form.
+ *
+ * @ingroup themeable
+ */
+function theme_system_date_time_settings($variables) {
+  $form = $variables['form'];
+  $header = array(
+    t('Date type'),
+    t('Format'),
+    t('Operations'),
   );
 
-  $default_medium_custom = variable_get('date_format_medium_custom', (isset($date_medium_choices[$date_format_medium]) ? $date_format_medium : ''));
-  $form['date_formats']['date_format_medium_custom'] = array(
-    '#prefix' => '<div class="custom-container">',
-    '#suffix' => '</div></div>',
+  foreach (element_children($form['format']) as $key) {
+    $delete_key = $key . '_delete';
+    $row = array();
+    $row[] = $form['format'][$key]['#title'];
+    unset($form['format'][$key]['#title']);
+    $row[] = array('data' => drupal_render($form['format'][$key]));
+    $row[] = array('data' => drupal_render($form['delete'][$delete_key]));
+    $rows[] = $row;
+  }
+
+  $output = theme('table', array('header' => $header, 'rows' => $rows, 'attributes' => array('id' => 'system-date-types')));
+  $output .= drupal_render_children($form);
+
+  return $output;
+}
+
+
+/**
+ * Add new date type.
+ *
+ * @ingroup forms
+ * @ingroup system_add_date_format_type_form_validate()
+ * @ingroup system_add_date_format_type_form_submit()
+ */
+function system_add_date_format_type_form($form, &$form_state) {
+  $form['date_type'] = array(
+    '#title' => t('Date type'),
     '#type' => 'textfield',
-    '#title' => t('Custom medium date format'),
-    '#attributes' => array('class' => array('custom-format')),
-    '#default_value' => $default_medium_custom,
-    '#description' => t('A user-defined medium date format. See the <a href="@url">PHP manual</a> for available options. This format is currently set to display as <span>%date</span>.', array('@url' => 'http://php.net/manual/function.date.php', '%date' => format_date(REQUEST_TIME, 'custom', $default_medium_custom))),
+    '#required' => TRUE,
+    '#field_suffix' => ' <small id="edit-date-type-suffix">&nbsp</small>',
+  );
+  $js_settings = array(
+    'type' => 'setting',
+    'data' => array(
+      'machineReadableValue' => array(
+        'date-type' => array(
+          'text' => t('Machine name'),
+          'target' => 'machine-name',
+          'searchPattern' => '[^a-z0-9]+',
+          'replaceToken' => '_',
+        ),
+      ),
+    ),
+  );
+  $form['machine_name'] = array(
+    '#title' => t('Machine readable name'),
+    '#description' => t('The unique machine readable name for this date type, can only contain lowercase letters, numbers and underscores.'),
+    '#type' => 'textfield',
+    '#required' => TRUE,
+    '#attached' => array(
+      'js' => array(drupal_get_path('module', 'system') . '/system.js', $js_settings),
+    ),
   );
 
-  $date_format_long = variable_get('date_format_long', $date_long[0]);
-  $form['date_formats']['date_format_long'] = array(
-    '#prefix' => '<div class="date-container"><div class="select-container">',
-    '#suffix' => '</div>',
+  // Get list of all available date formats.
+  $formats = array();
+  drupal_static_reset('system_get_date_formats');
+  $date_formats = system_get_date_formats(); // Call this to rebuild the list, and to have default list.
+  foreach ($date_formats as $type => $format_info) {
+    $formats = array_merge($formats, $format_info);
+  }
+  $custom_formats = system_get_date_formats('custom');
+  if (!empty($custom_formats)) {
+    $formats = array_merge($formats, $custom_formats);
+  }
+  $choices = array();
+  foreach ($formats as $f => $format) {
+    $choices[$f] = format_date(REQUEST_TIME, 'custom', $f);
+  }
+  // Show date format select list.
+  $form['date_format'] = array(
     '#type' => 'select',
-    '#title' => t('Long date format'),
+    '#title' => t('Date format'),
     '#attributes' => array('class' => array('date-format')),
-    '#default_value' => (isset($date_long_choices[$date_format_long]) ? $date_format_long : 'custom'),
-    '#options' => $date_long_choices,
+    '#options' => $choices,
+    '#required' => TRUE,
   );
 
-  $default_long_custom = variable_get('date_format_long_custom', (isset($date_long_choices[$date_format_long]) ? $date_format_long : ''));
-  $form['date_formats']['date_format_long_custom'] = array(
-    '#prefix' => '<div class="custom-container">',
-    '#suffix' => '</div></div>',
-    '#type' => 'textfield',
-    '#title' => t('Custom long date format'),
-    '#attributes' => array('class' => array('custom-format')),
-    '#default_value' => $default_long_custom,
-    '#description' => t('A user-defined long date format. See the <a href="@url">PHP manual</a> for available options. This format is currently set to display as <span>%date</span>.', array('@url' => 'http://php.net/manual/function.date.php', '%date' => format_date(REQUEST_TIME, 'custom', $default_long_custom))),
+  $form['submit'] = array(
+    '#type' => 'submit',
+    '#value' => t('Add date type'),
   );
 
-  $form = system_settings_form($form, FALSE);
-  // We will call system_settings_form_submit() manually, so remove it for now.
-  unset($form['#submit']);
+  $form['#validate'][] = 'system_add_date_format_type_form_validate';
+  $form['#submit'][] = 'system_add_date_format_type_form_submit';
+
   return $form;
 }
 
 /**
- * Process system_regional_settings form submissions.
+ * Validate system_add_date_format_type form submissions.
  */
-function system_regional_settings_submit($form, &$form_state) {
-  if ($form_state['values']['date_format_short'] == 'custom') {
-    $form_state['values']['date_format_short'] = $form_state['values']['date_format_short_custom'];
-  }
-  if ($form_state['values']['date_format_medium'] == 'custom') {
-    $form_state['values']['date_format_medium'] = $form_state['values']['date_format_medium_custom'];
-  }
-  if ($form_state['values']['date_format_long'] == 'custom') {
-    $form_state['values']['date_format_long'] = $form_state['values']['date_format_long_custom'];
+function system_add_date_format_type_form_validate($form, &$form_state) {
+  if (!empty($form_state['values']['machine_name']) && !empty($form_state['values']['date_type'])) {
+    if (!preg_match("/^[a-zA-Z0-9_]+$/", trim($form_state['values']['machine_name']))) {
+      form_set_error('machine_name', t('The date type must contain only alphanumeric characters and underscores.'));
+    }
+    $types = system_get_date_types();
+    if (in_array(trim($form_state['values']['machine_name']), array_keys($types))) {
+      form_set_error('machine_name', t('This date type already exists. Please enter a unique type.'));
+    }
   }
-  return system_settings_form_submit($form, $form_state);
+}
+
+/**
+ * Process system_add_date_format_type form submissions.
+ */
+function system_add_date_format_type_form_submit($form, &$form_state) {
+  $machine_name = trim($form_state['values']['machine_name']);
+
+  $format_type = array();
+  $format_type['title'] = trim($form_state['values']['date_type']);
+  $format_type['type'] = $machine_name;
+  $format_type['locked'] = 0;
+  $format_type['is_new'] = 1;
+  system_date_format_type_save($format_type);
+  variable_set('date_format_' . $machine_name, $form_state['values']['date_format']);
+
+  drupal_set_message(t('New date type added successfully.'));
+  $form_state['redirect'] = 'admin/config/regional/date-time';
 }
 
 /**
@@ -1931,7 +2020,7 @@ function system_php() {
 function system_batch_page() {
   require_once DRUPAL_ROOT . '/includes/batch.inc';
   $output = _batch_page();
-  
+
   // Use the same theme that the page that started the batch.
   $batch = &batch_get();
   $GLOBALS['custom_theme'] = $batch['theme'];
@@ -2341,6 +2430,185 @@ function theme_system_themes_form($variables) {
 }
 
 /**
+ * Menu callback; present a form for deleting a date format.
+ */
+function system_date_delete_format_form($form, &$form_state, $dfid) {
+  $form['dfid'] = array(
+    '#type' => 'value',
+    '#value' => $dfid,
+  );
+  $format = system_get_date_format($dfid);
+
+  $output = confirm_form($form,
+    t('Are you sure you want to remove the format %format?', array('%format' => format_date(REQUEST_TIME, 'custom', $format->format))),
+    'admin/config/regional/date-time/formats',
+    t('This action cannot be undone.'),
+    t('Remove'), t('Cancel'),
+    'confirm'
+  );
+
+  return $output;
+}
+
+/**
+ * Delete a configured date format.
+ */
+function system_date_delete_format_form_submit($form, &$form_state) {
+  if ($form_state['values']['confirm']) {
+    $format = system_get_date_format($form_state['values']['dfid']);
+    system_date_format_delete($form_state['values']['dfid']);
+    drupal_set_message(t('Removed date format %format.', array('%format' => format_date(REQUEST_TIME, 'custom', $format->format))));
+    $form_state['redirect'] = 'admin/config/regional/date-time/formats';
+  }
+}
+
+/**
+ * Menu callback; present a form for deleting a date type.
+ */
+function system_delete_date_format_type_form($form, &$form_state, $format_type) {
+  $form['format_type'] = array(
+    '#type' => 'value',
+    '#value' => $format_type,
+  );
+  $type_info = system_get_date_types($format_type);
+
+  $output = confirm_form($form,
+    t('Are you sure you want to remove the date type %type?', array('%type' => $type_info['title'])),
+    'admin/config/regional/date-time',
+    t('This action cannot be undone.'),
+    t('Remove'), t('Cancel'),
+    'confirm'
+  );
+
+  return $output;
+}
+
+/**
+ * Delete a configured date type.
+ */
+function system_delete_date_format_type_form_submit($form, &$form_state) {
+  if ($form_state['values']['confirm']) {
+    $type_info = system_get_date_types($form_state['values']['format_type']);
+    system_date_format_type_delete($form_state['values']['format_type']);
+    drupal_set_message(t('Removed date type %type.', array('%type' => $type_info['title'])));
+    $form_state['redirect'] = 'admin/config/regional/date-time';
+  }
+}
+
+
+/**
+ * Displays the date format strings overview page.
+ */
+function system_date_time_formats() {
+  $header = array(t('Format'), array('data' => t('Operations'), 'colspan' => '2'));
+  $rows = array();
+
+  drupal_static_reset('system_get_date_formats');
+  $formats = system_get_date_formats('custom');
+  if (!empty($formats)) {
+    foreach ($formats as $format) {
+      $row = array();
+      $row[] = array('data' => format_date(REQUEST_TIME, 'custom', $format['format']));
+      $row[] = array('data' => l(t('edit'), 'admin/config/regional/date-time/formats/' . $format['dfid'] . '/edit'));
+      $row[] = array('data' => l(t('delete'), 'admin/config/regional/date-time/formats/' . $format['dfid'] . '/delete'));
+      $rows[] = $row;
+    }
+  }
+
+  if (empty($rows)) {
+    $rows[] = array(array('data' => t('No custom date formats available. <a href="@link">Add date format</a>.', array('@link' => url('admin/config/regional/date-time/formats/add'))), 'colspan' => '5', 'class' => array('message')));
+  }
+
+  $build['date_formats_table'] = array(
+    '#theme' => 'table',
+    '#header' => $header,
+    '#rows' => $rows,
+  );
+
+  return $build;
+}
+
+/**
+ * Allow users to add additional date formats.
+ */
+function system_configure_date_formats_form($form, &$form_state, $dfid = 0) {
+  $js_settings = array(
+    'type' => 'setting',
+    'data' => array(
+      'dateTime' => array(
+        'date-format' => array(
+          'text' => t('Displayed as'),
+          'lookup' => url('admin/config/regional/date-time/formats/lookup'),
+        ),
+      ),
+    ),
+  );
+
+  if ($dfid) {
+    $form['dfid'] = array(
+      '#type' => 'value',
+      '#value' => $dfid,
+    );
+    $format = system_get_date_format($dfid);
+  }
+
+  $now = ($dfid ? t('Displayed as %date', array('%date' => format_date(REQUEST_TIME, 'custom', $format->format))) : '');
+
+  $form['date_format'] = array(
+    '#type' => 'textfield',
+    '#title' => t('Format string'),
+    '#description' => t('A user-defined date format. See the <a href="@url">PHP manual</a> for available options.', array('@url' => 'http://php.net/manual/function.date.php')),
+    '#default_value' => ($dfid ? $format->format : ''),
+    '#field_suffix' => ' <small id="edit-date-format-suffix">' . $now . '</small>',
+    '#attached' => array(
+      'js' => array(drupal_get_path('module', 'system') . '/system.js', $js_settings),
+    ),
+  );
+
+  $form['update'] = array(
+    '#type' => 'submit',
+    '#value' => ($dfid ? t('Save format') : t('Add format')),
+  );
+
+  $form['#validate'][] = 'system_add_date_formats_form_validate';
+  $form['#submit'][] = 'system_add_date_formats_form_submit';
+
+  return $form;
+}
+
+/**
+ * Validate new date format string submission.
+ */
+function system_add_date_formats_form_validate($form, &$form_state) {
+  $formats = system_get_date_formats('custom');
+  $format = trim($form_state['values']['date_format']);
+  if (!empty($formats) && in_array($format, array_keys($formats)) && (!isset($form_state['values']['dfid']) || $form_state['values']['dfid'] != $formats[$format]['dfid'])) {
+    form_set_error('date_format', t('This format already exists. Please enter a unique format string.'));
+  }
+}
+
+/**
+ * Process new date format string submission.
+ */
+function system_add_date_formats_form_submit($form, &$form_state) {
+  $format = array();
+  $format['format'] = trim($form_state['values']['date_format']);
+  $format['type'] = 'custom';
+  $format['locked'] = 0;
+  if (!empty($form_state['values']['dfid'])) {
+    system_date_format_save($format, $form_state['values']['dfid']);
+    drupal_set_message(t('Custom date format updated.'));
+  }
+  else {
+    $format['is_new'] = 1;
+    system_date_format_save($format);
+    drupal_set_message(t('Custom date format added.'));
+  }
+
+  $form_state['redirect'] = 'admin/config/regional/date-time/formats';
+}
+
+/**
  * Menu callback; Displays an overview of available and configured actions.
  */
 function system_actions_manage() {
diff --git a/modules/system/system.api.php b/modules/system/system.api.php
index 1c5094704..09812c9bb 100644
--- a/modules/system/system.api.php
+++ b/modules/system/system.api.php
@@ -2377,5 +2377,109 @@ function hook_action_info_alter(&$actions) {
 }
 
 /**
+ * Defines additional date types.
+ *
+ * Next to the 'long', 'medium' and 'short' date types defined in core, any
+ * module can define additional types that can be used when displaying dates. A
+ * date type is a key which can be passed to format_date() to return a date in
+ * the configured display format.
+ *
+ * To avoid namespace collisions with date types defined by other modules, it is
+ * recommended that each date type starts with the module name. A date type
+ * can consist of letters, numbers and underscores.
+ *
+ * @see hook_date_formats()
+ * @see format_date()
+ *
+ * @return
+ *   A list of date types in 'key' => 'label' format.
+ */
+function hook_date_format_types() {
+  return array(
+    'long' => t('Long'),
+    'medium' => t('Medium'),
+    'short' => t('Short'),
+  );
+}
+
+/**
+ * Defines additional date formats.
+ *
+ * Next to the 'long', 'medium' and 'short' date types defined in core, any
+ * module can define additional types that can be used when displaying dates. A
+ * date type is a key which can be passed to format_date() to return a date in
+ * the configured displayed format. A date format is a string defining the date
+ * and time elements to use. For example, a date type could be 
+ * 'mymodule_extra_long', while a date format is like 'Y-m-d'.
+ *
+ * New date types must first be declared using hook_date_format_types(). It is
+ * then possible to define one or more date formats for each.
+ *
+ * A module may also extend the list date formats defined for a date type
+ * provided by another module.
+ *
+ * There may be more than one format for the same locale. For example d/m/Y and
+ * Y/m/d work equally well in some locales. It may also be necessary to define
+ * multiple versions of the same date format, for example, one using AM, one
+ * with PM and one without the time at all.
+ *
+ * However at the same time you may wish to define some additional date formats
+ * that aren't specific to any one locale, for example, "Y m". For these cases
+ * the locales field should be omitted.
+ *
+ * @see hook_date_format_types()
+ *
+ * @return
+ *   A list of date formats. Each date format is a keyed array
+ *   consisting of three elements:
+ *   - 'type': the date type is a key used to identify which date format to
+ *     display. It consists of letters, numbers and underscores, e.g. 'long',
+ *     'short', 'mymodule_extra_long'. It must first be declared in
+ *     hook_date_format_types() unless extending a type provided by another
+ *     module.
+ *   - 'format': a string defining the date and time elements to use. It 
+ *     can contain any of the formatting options described at
+ *     http://php.net/manual/en/function.date.php
+ *   - 'locales': (optional) an array of 2 and 5 character language codes, for
+ *     example, 'en', 'en-us'. The language codes are used to determine which
+ *     date format to display for the user's current language. If more than one
+ *     date format is suggested for the same date type and locale, then the
+ *     first one will be used unless overridden via
+ *     admin/config/regional/date-time/locale. If your date format is not
+ *     language specific, leave this field empty.
+ */
+function hook_date_formats() {
+  return array(
+    array(
+      'type' => 'mymodule_extra_long',
+      'format' => 'l jS F Y H:i:s e',
+      'locales' => array('en-ie'),
+    ),
+    array(
+      'type' => 'mymodule_extra_long',
+      'format' => 'l jS F Y h:i:sa',
+      'locales' => array('en', 'en-us'),
+    ),
+    array(
+      'type' => 'short',
+      'format' => 'F Y',
+      'locales' => array(),
+    ),
+  );
+}
+
+/**
+ * Alters date types and formats declared by another module.
+ *
+ * Called by _system_date_format_types_build() to allow modules to alter the
+ * return values from implementations of hook_date_formats().
+ */
+function hook_date_formats_alter(&$formats) {
+  foreach ($formats as $id => $format) {
+    $formats[$id]['locales'][] = 'en-ca';
+  }
+}
+
+/**
  * @} End of "addtogroup hooks".
  */
diff --git a/modules/system/system.install b/modules/system/system.install
index 08ecacd5e..6564e0235 100644
--- a/modules/system/system.install
+++ b/modules/system/system.install
@@ -741,6 +741,92 @@ function system_schema() {
   $schema['cache_registry'] = $schema['cache'];
   $schema['cache_registry']['description'] = 'Cache table for the code registry system to remember what code files need to be loaded on any given page.';
 
+  $schema['date_format_type'] = array(
+    'description' => 'Stores configured date format types.',
+    'fields' => array(
+      'type' => array(
+        'description' => 'The date format type, e.g. medium.',
+        'type' => 'varchar',
+        'length' => 64,
+        'not null' => TRUE,
+      ),
+      'title' => array(
+        'description' => 'The human readable name of the format type.',
+        'type' => 'varchar',
+        'length' => 255,
+        'not null' => TRUE,
+      ),
+      'locked' => array(
+        'description' => 'Whether or not this is a system provided format.',
+        'type' => 'int',
+        'size' => 'tiny',
+        'default' => 0,
+        'not null' => TRUE,
+      ),
+    ),
+    'primary key' => array('type'),
+  );
+
+  // This table's name is plural as some versions of MySQL can't create a 
+  // table named 'date_format'.
+  $schema['date_formats'] = array(
+    'description' => 'Stores configured date formats.',
+    'fields' => array(
+      'dfid' => array(
+        'description' => 'The date format identifier.',
+        'type' => 'serial',
+        'not null' => TRUE,
+        'unsigned' => TRUE,
+      ),
+      'format' => array(
+        'description' => 'The date format string.',
+        'type' => 'varchar',
+        'length' => 100,
+        'not null' => TRUE,
+      ),
+      'type' => array(
+        'description' => 'The date format type, e.g. medium.',
+        'type' => 'varchar',
+        'length' => 64,
+        'not null' => TRUE,
+      ),
+      'locked' => array(
+        'description' => 'Whether or not this format can be modified.',
+        'type' => 'int',
+        'size' => 'tiny',
+        'default' => 0,
+        'not null' => TRUE,
+      ),
+    ),
+    'primary key' => array('dfid'),
+    'unique keys' => array('formats' => array('format', 'type')),
+  );
+
+  $schema['date_format_locale'] = array(
+    'description' => 'Stores configured date formats for each locale.',
+    'fields' => array(
+      'format' => array(
+        'description' => 'The date format string.',
+        'type' => 'varchar',
+        'length' => 100,
+        'not null' => TRUE,
+      ),
+      'type' => array(
+        'description' => 'The date format type, e.g. medium.',
+        'type' => 'varchar',
+        'length' => 64,
+        'not null' => TRUE,
+      ),
+      'language' => array(
+        'description' => 'A {languages}.language for this format to be used with.',
+        'type' => 'varchar',
+        'length' => 12,
+        'not null' => TRUE,
+      ),
+    ),
+    'primary key' => array('type', 'language'),
+  );
+
   $schema['file'] = array(
     'description' => 'Stores information for uploaded files.',
     'fields' => array(
@@ -2547,6 +2633,99 @@ function system_update_7039() {
 }
 
 /**
+ * Create new date format tables.
+ */
+function system_update_7040() {
+  $schema['date_format_type'] = array(
+    'description' => 'Stores configured date format types.',
+    'fields' => array(
+      'type' => array(
+        'description' => 'The date format type, e.g. medium.',
+        'type' => 'varchar',
+        'length' => 64,
+        'not null' => TRUE,
+      ),
+      'title' => array(
+        'description' => 'The human readable name of the format type.',
+        'type' => 'varchar',
+        'length' => 255,
+        'not null' => TRUE,
+      ),
+      'locked' => array(
+        'description' => 'Whether or not this is a system provided format.',
+        'type' => 'int',
+        'size' => 'tiny',
+        'default' => 0,
+        'not null' => TRUE,
+      ),
+    ),
+    'primary key' => array('type'),
+  );
+
+  $schema['date_formats'] = array(
+    'description' => 'Stores configured date formats.',
+    'fields' => array(
+      'dfid' => array(
+        'description' => 'The date format identifier.',
+        'type' => 'serial',
+        'not null' => TRUE,
+        'unsigned' => TRUE,
+      ),
+      'format' => array(
+        'description' => 'The date format string.',
+        'type' => 'varchar',
+        'length' => 100,
+        'not null' => TRUE,
+      ),
+      'type' => array(
+        'description' => 'The date format type, e.g. medium.',
+        'type' => 'varchar',
+        'length' => 64,
+        'not null' => TRUE,
+      ),
+      'locked' => array(
+        'description' => 'Whether or not this format can be modified.',
+        'type' => 'int',
+        'size' => 'tiny',
+        'default' => 0,
+        'not null' => TRUE,
+      ),
+    ),
+    'primary key' => array('dfid'),
+    'unique keys' => array('formats' => array('format', 'type')),
+  );
+
+  $schema['date_format_locale'] = array(
+    'description' => 'Stores configured date formats for each locale.',
+    'fields' => array(
+      'format' => array(
+        'description' => 'The date format string.',
+        'type' => 'varchar',
+        'length' => 100,
+        'not null' => TRUE,
+      ),
+      'type' => array(
+        'description' => 'The date format type, e.g. medium.',
+        'type' => 'varchar',
+        'length' => 64,
+        'not null' => TRUE,
+      ),
+      'language' => array(
+        'description' => 'A {languages}.language for this format to be used with.',
+        'type' => 'varchar',
+        'length' => 12,
+        'not null' => TRUE,
+      ),
+    ),
+    'primary key' => array('type', 'language'),
+  );
+
+  db_create_table('date_format_type', $schema['date_format_type']);
+  db_create_table('date_formats', $schema['date_formats']);
+  db_create_table('date_format_locale', $schema['date_format_locale']);
+}
+
+/**
  * @} End of "defgroup updates-6.x-to-7.x"
  * The next series of updates should start at 8000.
  */
diff --git a/modules/system/system.js b/modules/system/system.js
index 7df037283..83a0c81db 100644
--- a/modules/system/system.js
+++ b/modules/system/system.js
@@ -97,22 +97,20 @@ Drupal.behaviors.copyFieldValue = {
  */
 Drupal.behaviors.dateTime = {
   attach: function (context, settings) {
-    // Show/hide custom format depending on the select's value.
-    $('select.date-format', context).once('date-time').change(function () {
-      $(this).parents('div.date-container').children('div.custom-container')[$(this).val() == 'custom' ? 'show' : 'hide']();
-    });
+    for (var value in settings.dateTime) {
+      var settings = settings.dateTime[value];
+      var source = '#edit-' + value;
+      var suffix = source + '-suffix';
 
-    // Attach keyup handler to custom format inputs.
-    $('input.custom-format', context).once('date-time').keyup(function () {
-      var input = $(this);
-      var url = settings.dateTime.lookup + (settings.dateTime.lookup.match(/\?q=/) ? '&format=' : '?format=') + encodeURIComponent(input.val());
-      $.getJSON(url, function (data) {
-        $('div.description span', input.parent()).html(data);
+      // Attach keyup handler to custom format inputs.
+      $('input' + source, context).once('date-time').keyup(function () {
+        var input = $(this);
+        var url = settings.lookup + (settings.lookup.match(/\?q=/) ? '&format=' : '?format=') + encodeURIComponent(input.val());
+        $.getJSON(url, function (data) {
+          $(suffix).empty().append(' ' + settings.text + ': <em>' + data + '</em>');
+        });
       });
-    });
-
-    // Trigger the event handler to show the form input if necessary.
-    $('select.date-format', context).trigger('change');
+    }
   }
 };
 
diff --git a/modules/system/system.module b/modules/system/system.module
index 996894419..b6c25134b 100644
--- a/modules/system/system.module
+++ b/modules/system/system.module
@@ -101,7 +101,7 @@ function system_help($path, $arg) {
       $output .= '<li>' . t('support for enabling and disabling <a href="@themes">themes</a>, which determine the design and presentation of your site. Drupal comes packaged with several core themes and additional contributed themes are available at the <a href="@drupal-themes">Drupal.org theme page</a>.', array('@themes' => url('admin/appearance'), '@drupal-themes' => 'http://drupal.org/project/themes')) . '</li>';
       $output .= '<li>' . t('a robust <a href="@cache-settings">caching system</a> that allows the efficient re-use of previously-constructed web pages and web page components. Drupal stores the pages requested by anonymous users in a compressed format; depending on your site configuration and the amount of your web traffic tied to anonymous visitors, Drupal\'s caching system may significantly increase the speed of your site.', array('@cache-settings' => url('admin/config/development/performance'))) . '</li>';
       $output .= '<li>' . t('a set of routine administrative operations that rely on a correctly-configured <a href="@cron">cron maintenance task</a> to run automatically. A number of other modules, including the feed aggregator, and search also rely on <a href="@cron">cron maintenance tasks</a>. For more information, see the online handbook entry for <a href="@handbook">configuring cron jobs</a>.', array('@cron' => url('admin/reports/status'), '@handbook' => 'http://drupal.org/cron')) . '</li>';
-      $output .= '<li>' . t('basic configuration options for your site, including <a href="@regional-settings">date and time settings</a>, <a href="@file-system">file system settings</a>, <a href="@clean-url">clean URL support</a>, <a href="@site-info">site name and other information</a>, and a <a href="@maintenance-mode">maintenance mode</a> for taking your site temporarily offline.', array('@regional-settings' => url('admin/config/regional/settings'), '@file-system' => url('admin/config/media/file-system'), '@clean-url' => url('admin/config/search/clean-urls'), '@site-info' => url('admin/config/system/site-information'), '@maintenance-mode' => url('admin/config/development/maintenance'))) . '</li></ul>';
+      $output .= '<li>' . t('basic configuration options for your site, including <a href="@date-time-settings">date and time settings</a>, <a href="@file-system">file system settings</a>, <a href="@clean-url">clean URL support</a>, <a href="@site-info">site name and other information</a>, and a <a href="@maintenance-mode">maintenance mode</a> for taking your site temporarily offline.', array('@date-time-settings' => url('admin/config/regional/date-time'), '@file-system' => url('admin/config/media/file-system'), '@clean-url' => url('admin/config/search/clean-urls'), '@site-info' => url('admin/config/system/site-information'), '@maintenance-mode' => url('admin/config/development/maintenance'))) . '</li></ul>';
       $output .= '<p>' . t('For more information, see the online handbook entry for <a href="@system">System module</a>.', array('@system' => 'http://drupal.org/handbook/modules/system/')) . '</p>';
       return $output;
     case 'admin/by-module':
@@ -204,6 +204,10 @@ function system_theme() {
     'system_run_cron_image' => array(
       'arguments' => array('image_path' => NULL),
     ),
+    'system_date_time_settings' => array(
+      'arguments' => array('form' => NULL),
+      'file' => 'system.admin.inc',
+    ),
   ));
 }
 
@@ -781,6 +785,8 @@ function system_menu() {
     'access arguments' => array('administer site configuration'),
     'file' => 'system.admin.inc',
   );
+
+  // Regional and date settings.
   $items['admin/config/regional'] = array(
     'title' => 'Regional and language',
     'description' => 'Regional settings, localization and translation.',
@@ -792,20 +798,96 @@ function system_menu() {
   );
   $items['admin/config/regional/settings'] = array(
     'title' => 'Regional settings',
-    'description' => "Settings for how Drupal displays date and time, as well as the system's default time zone.",
+    'description' => "Settings for the site's default time zone and country.",
     'page callback' => 'drupal_get_form',
     'page arguments' => array('system_regional_settings'),
     'access arguments' => array('administer site configuration'),
     'weight' => -10,
     'file' => 'system.admin.inc',
   );
-  $items['admin/config/regional/settings/lookup'] = array(
+  $items['admin/config/regional/date-time'] = array(
+    'title' => 'Date and time',
+    'description' => 'Configure display formats for date and time.',
+    'page callback' => 'drupal_get_form',
+    'page arguments' => array('system_date_time_settings'),
+    'access arguments' => array('administer site configuration'),
+    'weight' => -9,
+    'file' => 'system.admin.inc',
+  );
+  $items['admin/config/regional/date-time/types'] = array(
+    'title' => 'Types',
+    'description' => 'Configure display formats for date and time.',
+    'page callback' => 'drupal_get_form',
+    'page arguments' => array('system_date_time_settings'),
+    'access arguments' => array('administer site configuration'),
+    'type' => MENU_DEFAULT_LOCAL_TASK,
+    'weight' => -10,
+    'file' => 'system.admin.inc',
+  );
+  $items['admin/config/regional/date-time/types/add'] = array(
+    'title' => 'Add date type',
+    'description' => 'Add new date type.',
+    'page callback' => 'drupal_get_form',
+    'page arguments' => array('system_add_date_format_type_form'),
+    'access arguments' => array('administer site configuration'),
+    'type' => MENU_LOCAL_ACTION,
+    'weight' => -10,
+    'file' => 'system.admin.inc',
+  );
+  $items['admin/config/regional/date-time/types/%/delete'] = array(
+    'title' => 'Delete date type',
+    'description' => 'Allow users to delete a configured date type.',
+    'type' => MENU_CALLBACK,
+    'page callback' => 'drupal_get_form',
+    'page arguments' => array('system_delete_date_format_type_form', 5),
+    'access arguments' => array('administer site configuration'),
+    'file' => 'system.admin.inc',
+  );
+  $items['admin/config/regional/date-time/formats'] = array(
+    'title' => 'Formats',
+    'description' => 'Configure display format strings for date and time.',
+    'page callback' => 'system_date_time_formats',
+    'access arguments' => array('administer site configuration'),
+    'type' => MENU_LOCAL_TASK,
+    'weight' => -9,
+    'file' => 'system.admin.inc',
+  );
+  $items['admin/config/regional/date-time/formats/add'] = array(
+    'title' => 'Add format',
+    'description' => 'Allow users to add additional date formats.',
+    'type' => MENU_LOCAL_ACTION,
+    'page callback' => 'drupal_get_form',
+    'page arguments' => array('system_configure_date_formats_form'),
+    'access arguments' => array('administer site configuration'),
+    'weight' => -10,
+    'file' => 'system.admin.inc',
+  );
+  $items['admin/config/regional/date-time/formats/%/edit'] = array(
+    'title' => 'Edit date format',
+    'description' => 'Allow users to edit a configured date format.',
+    'type' => MENU_CALLBACK,
+    'page callback' => 'drupal_get_form',
+    'page arguments' => array('system_configure_date_formats_form', 5),
+    'access arguments' => array('administer site configuration'),
+    'file' => 'system.admin.inc',
+  );
+  $items['admin/config/regional/date-time/formats/%/delete'] = array(
+    'title' => 'Delete date format',
+    'description' => 'Allow users to delete a configured date format.',
+    'type' => MENU_CALLBACK,
+    'page callback' => 'drupal_get_form',
+    'page arguments' => array('system_date_delete_format_form', 5),
+    'access arguments' => array('administer site configuration'),
+    'file' => 'system.admin.inc',
+  );
+  $items['admin/config/regional/date-time/formats/lookup'] = array(
     'title' => 'Date and time lookup',
     'type' => MENU_CALLBACK,
     'page callback' => 'system_date_time_lookup',
     'access arguments' => array('administer site configuration'),
     'file' => 'system.admin.inc',
   );
+
   $items['admin/config/search'] = array(
     'title' => 'Search and metadata',
     'description' => 'Local site search, metadata and SEO.',
@@ -2454,6 +2536,14 @@ function system_cron() {
 }
 
 /**
+ * Implements hook_flush_caches().
+ */
+function system_flush_caches() {
+  // Rebuild list of date formats.
+  system_date_formats_rebuild();
+}
+
+/**
  * Implement hook_action_info().
  */
 function system_action_info() {
@@ -2921,3 +3011,353 @@ function theme_system_run_cron_image($variables) {
   return '<noscript><div id="system-cron-image">' . theme('image', array('path' => $variables['image_path'], 'getsize' => FALSE)) . '</div></noscript>';
 }
 
+/**
+ * Get the list of available date types and attributes.
+ *
+ * @param $type
+ *   The date type, e.g. 'short', 'medium', 'long', 'custom'. If empty, then
+ *   all attributes for that type will be returned.
+ * @return
+ *   Array of date types.
+ */
+function system_get_date_types($type = NULL) {
+  $date_format_types = &drupal_static(__FUNCTION__);
+
+  if (!isset($date_format_types)) {
+    $date_format_types = _system_date_format_types_build();
+  }
+
+  return $type ? (isset($date_format_types[$type]) ? $date_format_types[$type] : FALSE) : $date_format_types;
+}
+
+/**
+ * Implements hook_date_format_types().
+ */
+function system_date_format_types() {
+  return array(
+    'long' => t('Long'),
+    'medium' => t('Medium'),
+    'short' => t('Short'),
+  );
+}
+
+/**
+ * Implements hook_date_formats().
+ *
+ * @return
+ *   An array of date formats with attributes 'type' (short, medium or long),
+ *   'format' (the format string) and 'locales'. The 'locales' attribute is an
+ *   array of locales, which can include both 2 character language codes like
+ *   'en', 'fr', but also 5 character language codes like 'en-gb' and 'en-us'.
+ */
+function system_date_formats() {
+  include_once DRUPAL_ROOT . '/includes/date.inc';
+  return system_default_date_formats();
+}
+
+/**
+ * Get the list of date formats for a particular format length.
+ *
+ * @param $type
+ *   The date type: 'short', 'medium', 'long', 'custom'. If empty, then all
+ *   available types will be returned.
+ * @return
+ *   Array of date formats.
+ */
+function system_get_date_formats($type = NULL) {
+  $date_formats = &drupal_static(__FUNCTION__);
+
+  if (!isset($date_formats)) {
+    $date_formats = _system_date_formats_build();
+  }
+
+  return $type ? (isset($date_formats[$type]) ? $date_formats[$type] : FALSE) : $date_formats;
+}
+
+/**
+ * Get the format details for a particular id.
+ *
+ * @param $dfid
+ *   Identifier of a date format string.
+ * @return
+ *   Array of date format details.
+ */
+function system_get_date_format($dfid) {
+  return db_query('SELECT df.dfid, df.format, df.type, df.locked FROM {date_formats} df WHERE df.dfid = :dfid', array(':dfid' => $dfid))->fetch();
+}
+
+/**
+ * Resets the database cache of date formats and saves all new formats.
+ */
+function system_date_formats_rebuild() {
+  drupal_static_reset('system_get_date_formats');
+  $date_formats = system_get_date_formats(NULL);
+
+  foreach ($date_formats as $format_type => $formats) {
+    foreach ($formats as $format => $info) {
+      system_date_format_save($info);
+    }
+  }
+
+  // Rebuild configured date formats locale list.
+  drupal_static_reset('system_date_format_locale');
+  system_date_format_locale();
+
+  _system_date_formats_build();
+}
+
+/**
+ * Get the appropriate date format for a type and locale.
+ *
+ * @param $langcode
+ *   Language code for the current locale. This can be a 2 character language
+ *   code like 'en', 'fr', or a longer 5 character code like 'en-gb'.
+ * @param $type
+ *   Date type: short, medium, long, custom.
+ * @return
+ *   The format string, or NULL if no matching format found.
+ */
+function system_date_format_locale($langcode = NULL, $type = NULL) {
+  $formats = &drupal_static(__FUNCTION__);
+
+  if (empty($formats)) {
+    $formats = array();
+    $result = db_query("SELECT format, type, language FROM {date_format_locale}");
+    foreach ($result as $record) {
+      if (!isset($formats[$record->language])) {
+        $formats[$record->language] = array();
+      }
+      $formats[$record->language][$record->type] = $record->format;
+    }
+  }
+
+  if ($type && $langcode && !empty($formats[$langcode][$type])) {
+    return $formats[$langcode][$type];
+  }
+  elseif ($langcode && !empty($formats[$langcode])) {
+    return $formats[$langcode];
+  }
+
+  return FALSE;
+}
+
+/**
+ * Builds and returns the list of available date types.
+ *
+ * @return
+ *   Array of date types.
+ */
+function _system_date_format_types_build() {
+  $types = array();
+
+  // Get list of modules which implement hook_date_format_types().
+  $modules = module_implements('date_format_types');
+
+  foreach ($modules as $module) {
+    $module_types = module_invoke($module, 'date_format_types');
+    foreach ($module_types as $module_type => $type_title) {
+      $type = array();
+      $type['module'] = $module;
+      $type['type'] = $module_type;
+      $type['title'] = $type_title;
+      $type['locked'] = 1;
+      $type['is_new'] = TRUE; // Will be over-ridden later if in the db.
+      $types[$module_type] = $type;
+    }
+  }
+
+  // Get custom formats added to the database by the end user.
+  $result = db_query('SELECT dft.type, dft.title, dft.locked FROM {date_format_type} dft ORDER BY dft.title');
+  foreach ($result as $record) {
+    if (!in_array($record->type, $types)) {
+      $type = array();
+      $type['is_new'] = FALSE;
+      $type['module'] = '';
+      $type['type'] = $record->type;
+      $type['title'] = $record->title;
+      $type['locked'] = $record->locked;
+      $types[$record->type] = $type;
+    }
+    else {
+      $type = array();
+      $type['is_new'] = FALSE;  // Over-riding previous setting.
+      $types[$record->type] = array_merge($types[$record->type], $type);
+    }
+  }
+
+  // Allow other modules to modify these date types.
+  drupal_alter('date_format_types', $types);
+
+  return $types;
+}
+
+/**
+ * Builds and returns the list of available date formats.
+ *
+ * @return
+ *   Array of date formats.
+ */
+function _system_date_formats_build() {
+  $date_formats = array();
+
+  // First handle hook_date_format_types().
+  $types = _system_date_format_types_build();
+  foreach ($types as $type => $info) {
+    system_date_format_type_save($info);
+  }
+
+  // Get formats supplied by various contrib modules.
+  $module_formats = module_invoke_all('date_formats');
+
+  foreach ($module_formats as $module_format) {
+    $module_format['locked'] = 1; // System types are locked.
+    // If no date type is specified, assign 'custom'.
+    if (!isset($module_format['type'])) {
+      $module_format['type'] = 'custom';
+    }
+    if (!in_array($module_format['type'], array_keys($types))) {
+      continue;
+    }
+    if (!isset($date_formats[$module_format['type']])) {
+      $date_formats[$module_format['type']] = array();
+    }
+
+    // If another module already set this format, merge in the new settings.
+    if (isset($date_formats[$module_format['type']][$module_format['format']])) {
+      $date_formats[$module_format['type']][$module_format['format']] = array_merge_recursive($date_formats[$module_format['type']][$module_format['format']], $format);
+    }
+    else {
+      // This setting will be overridden later if it already exists in the db.
+      $module_format['is_new'] = TRUE;
+      $date_formats[$module_format['type']][$module_format['format']] = $module_format;
+    }
+  }
+
+  // Get custom formats added to the database by the end user.
+  $result = db_query('SELECT df.dfid, df.format, df.type, df.locked, dfl.language FROM {date_formats} df LEFT JOIN {date_format_type} dft ON df.type = dft.type LEFT JOIN {date_format_locale} dfl ON df.format = dfl.format AND df.type = dfl.type ORDER BY df.type, df.format');
+  foreach ($result as $record) {
+    // If this date type isn't set, initialise the array.
+    if (!isset($date_formats[$record->type])) {
+      $date_formats[$record->type] = array();
+    }
+    $format = (array) $record;
+    $format['is_new'] = FALSE; // It's in the db, so override this setting.
+    // If this format not already present, add it to the array.
+    if (!isset($date_formats[$record->type][$record->format])) {
+      $format['module'] = '';
+      $format['locales'] = array($record->language);
+      $date_formats[$record->type][$record->format] = $format;
+    }
+    // Format already present, so merge in settings.
+    else {
+      if (!empty($record->language)) {
+        $format['locales'] = array_merge($date_formats[$record->type][$record->format]['locales'], array($record->language));
+      }
+      $date_formats[$record->type][$record->format] = array_merge($date_formats[$record->type][$record->format], $format);
+    }
+  }
+
+  // Allow other modules to modify these formats.
+  drupal_alter('date_formats', $date_formats);
+
+  return $date_formats;
+}
+
+/**
+ * Save a date type to the database.
+ *
+ * @param $date_format_type
+ *   An array of attributes for a date type.
+ */
+function system_date_format_type_save($date_format_type) {
+  $type = array();
+  $type['type'] = $date_format_type['type'];
+  $type['title'] = $date_format_type['title'];
+  $type['locked'] = $date_format_type['locked'];
+
+  // Update date_format table.
+  if (!empty($date_format_type['is_new'])) {
+    drupal_write_record('date_format_type', $type);
+  }
+  else {
+    drupal_write_record('date_format_type', $type, 'type');
+  }
+}
+
+/**
+ * Delete a date type from the database.
+ *
+ * @param $date_format_type
+ *   The date type name.
+ */
+function system_date_format_type_delete($date_format_type) {
+  db_delete('date_formats')
+    ->condition('type', $date_format_type)
+    ->execute();
+  db_delete('date_format_type')
+    ->condition('type', $date_format_type)
+    ->execute();
+  db_delete('date_format_locale')
+    ->condition('type', $date_format_type)
+    ->execute();
+}
+
+/**
+ * Save a date format to the database.
+ *
+ * @param $date_format
+ *   An array of attributes for a date format.
+ * @param $dfid
+ *   If set, replace an existing date format with a new string using this
+ *   identifier.
+ */
+function system_date_format_save($date_format, $dfid = 0) {
+  $format = array();
+  $format['dfid'] = $dfid;
+  $format['type'] = $date_format['type'];
+  $format['format'] = $date_format['format'];
+  $format['locked'] = $date_format['locked'];
+
+  // Update date_format table.
+  if (!empty($date_format['is_new'])) {
+    drupal_write_record('date_formats', $format);
+  }
+  else {
+    $keys = ($dfid ? array('dfid') : array('format', 'type'));
+    drupal_write_record('date_formats', $format, $keys);
+  }
+
+  $languages = language_list('enabled');
+  $languages = $languages[1];
+
+  $locale_format = array();
+  $locale_format['type'] = $date_format['type'];
+  $locale_format['format'] = $date_format['format'];
+
+  // Check if the suggested language codes are configured and enabled.
+  if (!empty($date_format['locales'])) {
+    foreach ($date_format['locales'] as $langcode) {
+      // Only proceed if language is enabled.
+      if (in_array($langcode, $languages)) {
+        $is_existing = (bool) db_query_range('SELECT 1 FROM {date_format_locale} WHERE type = :type AND language = :language', 0, 1, array(':type' => $date_format['type'], ':language' => $langcode))->fetchField();
+        if (!$is_existing) {
+          $locale_format['language'] = $langcode;
+          drupal_write_record('date_format_locale', $locale_format);
+        }
+      }
+    }
+  }
+}
+
+/**
+ * Delete a date format from the database.
+ *
+ * @param $date_format_id
+ *   The date format string identifier.
+ */
+function system_date_format_delete($dfid) {
+  db_delete('date_formats')
+    ->condition('dfid', $dfid)
+    ->execute();
+}
+
diff --git a/modules/system/system.test b/modules/system/system.test
index 78bece99a..226adff0f 100644
--- a/modules/system/system.test
+++ b/modules/system/system.test
@@ -718,6 +718,15 @@ class DateTimeFunctionalTest extends DrupalWebTestCase {
     );
   }
 
+  function setUp() {
+    parent::setUp();
+
+    // Create admin user and log in admin user.
+    $this->admin_user = $this->drupalCreateUser(array('administer site configuration'));
+    $this->drupalLogin($this->admin_user);
+  }
+
+
   /**
    * Test time zones and DST handling.
    */
@@ -748,6 +757,77 @@ class DateTimeFunctionalTest extends DrupalWebTestCase {
     $this->drupalGet("node/$node2->nid");
     $this->assertText('2007-08-01 00:00:00 -0700', t('Date should be three hours ahead, with GMT offset of -7 hours.'));
   }
+
+  /**
+   * Test date type configuration.
+   */
+  function testDateTypeConfiguration() {
+    // Confirm system date types appear.
+    $this->drupalGet('admin/config/regional/date-time');
+    $this->assertText(t('Medium'), 'System date types appear in date type list.');
+    $this->assertNoRaw('href="/admin/config/regional/date-time/types/medium/delete"', 'No delete link appear for system date types.');
+
+    // Add custom date type.
+    $this->clickLink(t('Add date type'));
+    $date_type = $this->randomName(8);
+    $machine_name = 'machine_' . $date_type;
+    $date_format = 'd.m.Y - H:i';
+    $edit = array(
+      'date_type' => $date_type,
+      'machine_name' => $machine_name,
+      'date_format' => $date_format,
+    );
+    $this->drupalPost('admin/config/regional/date-time/types/add', $edit, t('Add date type'));
+    $this->assertEqual($this->getUrl(), url('admin/config/regional/date-time', array('absolute' => TRUE)), t('Correct page redirection.'));
+    $this->assertText(t('New date type added successfully.'), 'Date type added confirmation message appears.');
+    $this->assertText($date_type, 'Custom date type appears in the date type list.');
+    $this->assertText(t('delete'), 'Delete link for custom date type appears.');
+
+    // Delete custom date type.
+    $this->clickLink(t('delete'));
+    $this->drupalPost('admin/config/regional/date-time/types/' . $machine_name . '/delete', array(), t('Remove'));
+    $this->assertEqual($this->getUrl(), url('admin/config/regional/date-time', array('absolute' => TRUE)), t('Correct page redirection.'));
+    $this->assertText(t('Removed date type ' . $date_type), 'Custom date type removed.');
+  }
+
+  /**
+   * Test date format configuration.
+   */
+  function testDateFormatConfiguration() {
+    // Confirm 'no custom date formats available' message appears.
+    $this->drupalGet('admin/config/regional/date-time/formats');
+    $this->assertText(t('No custom date formats available.'), 'No custom date formats message appears.');
+
+    // Add custom date format.
+    $this->clickLink(t('Add format'));
+    $edit = array(
+      'date_format' => 'Y',
+    );
+    $this->drupalPost('admin/config/regional/date-time/formats/add', $edit, t('Add format'));
+    $this->assertEqual($this->getUrl(), url('admin/config/regional/date-time/formats', array('absolute' => TRUE)), t('Correct page redirection.'));
+    $this->assertNoText(t('No custom date formats available.'), 'No custom date formats message does not appear.');
+    $this->assertText(t('Custom date format added.'), 'Custom date format added.');
+
+    // Ensure custom date format appears in date type configuration options.
+    $this->drupalGet('admin/config/regional/date-time');
+    $this->assertRaw('<option value="Y">', 'Custom date format appears in options.');
+
+    // Edit custom date format.
+    $this->drupalGet('admin/config/regional/date-time/formats');
+    $this->clickLink(t('edit'));
+    $edit = array(
+      'date_format' => 'Y m',
+    );
+    $this->drupalPost($this->getUrl(), $edit, t('Save format'));
+    $this->assertEqual($this->getUrl(), url('admin/config/regional/date-time/formats', array('absolute' => TRUE)), t('Correct page redirection.'));
+    $this->assertText(t('Custom date format updated.'), 'Custom date format successfully updated.');
+
+    // Delete custom date format.
+    $this->clickLink(t('delete'));
+    $this->drupalPost($this->getUrl(), array(), t('Remove'));
+    $this->assertEqual($this->getUrl(), url('admin/config/regional/date-time/formats', array('absolute' => TRUE)), t('Correct page redirection.'));
+    $this->assertText(t('Removed date format'), 'Custom date format removed successfully.');
+  }
 }
 
 class PageTitleFiltering extends DrupalWebTestCase {