<?php

/**
 * @file
 * Plugin to provide access control based on user permission strings.
 */

/**
 * Plugins are described by creating a $plugin array which will be used
 * by the system that includes this file.
 */
$plugin = array(
  'title' => t("User: permission"),
  'description' => t('Control access by permission string.'),
  'callback' => 'ctools_perm_ctools_access_check',
  'default' => array('perm' => 'access content'),
  'settings form' => 'ctools_perm_ctools_access_settings',
  'summary' => 'ctools_perm_ctools_access_summary',
  'required context' => new ctools_context_required(t('User'), 'user'),
);

/**
 * Settings form for the 'by perm' access plugin
 */
function ctools_perm_ctools_access_settings($form, &$form_state, $conf) {
  $perms = array();
  // Get list of permissions
  foreach (module_list(FALSE, FALSE, TRUE) as $module) {
    // By keeping them keyed by module we can use optgroups with the
    // 'select' type.
    if ($permissions = module_invoke($module, 'permission')) {
      foreach ($permissions as $id => $permission) {
        $perms[$module][$id] = $permission['title'];
      }
    }
  }

  $form['settings']['perm'] = array(
    '#type' => 'select',
    '#options' => $perms,
    '#title' => t('Permission'),
    '#default_value' => $conf['perm'],
    '#description' => t('Only users with the selected permission flag will be able to access this.'),
  );

  return $form;
}

/**
 * Check for access.
 */
function ctools_perm_ctools_access_check($conf, $context) {
  // As far as I know there should always be a context at this point, but this
  // is safe.
  if (empty($context) || empty($context->data)) {
    return FALSE;
  }

  return user_access($conf['perm'], $context->data);
}

/**
 * Provide a summary description based upon the checked roles.
 */
function ctools_perm_ctools_access_summary($conf, $context) {
  if (!isset($conf['perm'])) {
    return t('Error, unset permission');
  }

  $permissions = module_invoke_all('permission');
  return t('@identifier has "@perm"', array('@identifier' => $context->identifier, '@perm' => $permissions[$conf['perm']]['title']));
}