<?php


/**
 * Implements hook_menu_link_alter().
 *
 * In order to have our menu_item_visibility_translated_menu_link_alter()
 * function called by _menu_link_translate(), we have to manually set this
 * menu link as 'altered'. Unfortunately this alters all menu links and we need
 * to figure out a better solution in order to not globally alter all links.
 */
function menu_item_visibility_menu_link_alter(&$item) {
  $item['options']['alter'] = TRUE;

  // Because menu_link_save() may skip calling hook_menu_link_update(), we need
  // to force it to be invoked. See http://drupal.org/node/1013856.
  if (!empty($item['mlid'])) {
    _menu_item_visibility_menu_link_update($item);
  }
}

/**
 * Implements hook_translated_menu_link_alter().
 */
function menu_item_visibility_translated_menu_link_alter(&$item, $map) {
  global $user;

  if (!empty($item['access'])) {
    // Menu administrators can see all links.
    if (strpos(current_path(), 'admin/structure/menu/manage/' . $item['menu_name']) === 0 && user_access('administer menu')) {
      return;
    }

    // @todo Convert this into a proper hook so modules can extend visibility.
    $item['visibility'] = menu_item_visibility_load($item['mlid']);
    if (!empty($item['visibility']['roles']) && !array_intersect($item['visibility']['roles'], array_keys($user->roles))) {
      $item['access'] = FALSE;
    }
  }
}

/**
 * Load all visibility data for a menu link.
 */
function menu_item_visibility_load($mlid) {
  $visibility = array();
  if (!empty($mlid)) {
    $visibility['roles'] = db_query("SELECT rid FROM {menu_links_visibility_role} WHERE mlid = :mlid", array(':mlid' => $mlid))->fetchCol();
    module_invoke_all('menu_item_visibility_load', $visibility, $mlid);
  }
  return $visibility;
}

/**
 * Implements hook_menu_link_insert()
 */
function menu_item_visibility_menu_link_insert($link) {
  if (!empty($link['roles']) && $roles = array_filter($link['roles'])) {
    $query = db_insert('menu_links_visibility_role');
    $query->fields(array('mlid', 'rid'));
    foreach ($roles as $rid) {
      $query->values(array('mlid' => $link['mlid'], 'rid' => $rid));
    }
    $query->execute();
  }
}

/**
 * Implements hook_menu_link_update()
 *
 * Disabled as a hook until http://drupal.org/node/1013856 is fixed.
 */
function _menu_item_visibility_menu_link_update($link) {
  db_delete('menu_links_visibility_role')
    ->condition('mlid', $link['mlid'])
    ->execute();

  menu_item_visibility_menu_link_insert($link);
}

/**
 * Implements hook_menu_link_delete()
 */
function menu_item_visibility_menu_link_delete($link) {
  db_delete('menu_links_visibility_role')
    ->condition('mlid', $link['mlid'])
    ->execute();
}

/**
 * Implements hook_user_role_delete()
 */
function menu_item_visibility_user_role_delete($role) {
  db_delete('menu_links_visibility_role')
    ->condition('rid', $role->rid)
    ->execute();
}

/**
 * Implements hook_form_FORM_ID_alter().
 */
function menu_item_visibility_form_menu_edit_item_alter(&$form, &$form_state) {
  // Visibility settings.
  $form['visibility_title'] = array(
    '#type' => 'item',
    '#title' => t('Visibility settings'),
  );
  $form['visibility'] = array(
    '#type' => 'vertical_tabs',
    '#attached' => array(
      'js' => array(
        'vertical-tabs' => drupal_get_path('module', 'menu_item_visibility') . '/menu_item_visibility.js',
      ),
    ),
  );

  $visibility = menu_item_visibility_load($form['mlid']['#value']);

  // Per-role visibility.
  $form['visibility']['role'] = array(
    '#type' => 'fieldset',
    '#title' => t('Roles'),
    '#collapsible' => TRUE,
    '#collapsed' => TRUE,
    '#group' => 'visibility',
    '#weight' => 10,
  );
  $form['visibility']['role']['roles'] = array(
    '#type' => 'checkboxes',
    '#title' => t('Show menu link for specific roles'),
    '#default_value' => isset($visibility['roles']) ? $visibility['roles'] : array(),
    '#options' => array_map('check_plain', user_roles()),
    '#description' => t('Show this menu link only for the selected role(s). If you select no roles, the menu link will be visible to all users.'),
  );
}