system.module

<?php
/**
 * @file
 * Configuration system that lets administrators modify the workings of the site.
 */

/**
 * Maximum age of temporary files in seconds.
 */
define('BACKDROP_MAXIMUM_TEMP_FILE_AGE', 21600);

/**
 * New users will be set to the default time zone at registration.
 */
define('BACKDROP_USER_TIMEZONE_DEFAULT', 0);

/**
 * New users will get an empty time zone at registration.
 */
define('BACKDROP_USER_TIMEZONE_EMPTY', 1);

/**
 * New users will select their own timezone at registration.
 */
define('BACKDROP_USER_TIMEZONE_SELECT', 2);

 /**
 * Disabled option on forms and settings
 */
define('BACKDROP_DISABLED', 0);

/**
 * Optional option on forms and settings
 */
define('BACKDROP_OPTIONAL', 1);

/**
 * Required option on forms and settings
 */
define('BACKDROP_REQUIRED', 2);

/**
 * Maximum number of values in a weight select element.
 *
 * If the number of values is over the maximum, a text field is used instead.
 */
define('BACKDROP_WEIGHT_SELECT_MAX', 100);

/**
 * Maximum length of email fields.
 */
define('EMAIL_MAX_LENGTH', 254);

/**
 * The maximum depth for token tree recursion.
 */
define('TOKEN_MAX_DEPTH', 9);

/**
 * Implements hook_theme().
 */
function system_theme() {
  $base = array(
    'file' => 'system.theme.inc',
  );

  return array_merge(backdrop_common_theme(), array(
    'system_themes_page' => array(
      'variables' => array('theme_groups' => NULL),
    ) + $base,
    'system_settings_form' => array(
      'render element' => 'form',
    ) + $base,
    'confirm_form' => array(
      'render element' => 'form',
    ) + $base,
    'system_modules_fieldset' => array(
      'render element' => 'form',
    ) + $base,
    'system_modules_incompatible' => array(
      'variables' => array('message' => NULL),
    ) + $base,
    'system_modules_uninstall' => array(
      'render element' => 'form',
    ) + $base,
    'status_report' => array(
      'render element' => 'requirements',
    ) + $base,
    'admin_page' => array(
      'variables' => array('blocks' => NULL),
    ) + $base,
    'admin_block' => array(
      'variables' => array('block' => NULL),
    ) + $base,
    'admin_block_content' => array(
      'variables' => array('content' => NULL),
    ) + $base,
    'page_components' => array(
      'variables' => array('settings' => NULL, 'child_delta' => NULL),
      'template' => 'templates/page-components',
    ) + $base,
    'system_admin_index' => array(
      'variables' => array('menu_items' => NULL),
    ) + $base,
    'system_powered_by' => array(
      'variables' => array(),
    ) + $base,
    'block__system__main' => array(
      'template' => 'templates/block--system--main',
      //'variables' => array('content' => NULL, 'layout' => NULL, 'block' => NULL, 'style' => NULL, 'settings' => array(), 'attributes' => array()),
      'base hook' => 'block',
    ) + $base,
    'tree_table' => array(
      'variables' => array(
        'header' => array(),
        'rows' => array(),
        'attributes' => array(),
        'empty' => '',
        'caption' => '',
      ),
    ) + $base,
    'token_tree' => array(
      'variables' => array(
        'text' => t('Browse available tokens.'),
        'token_types' => array(),
        'global_types' => TRUE,
        'dialog' => FALSE,
        'click_insert' => TRUE,
        'show_restricted' => FALSE,
      ),
    ) + $base,
    'token_tree_link' => array(
      'variables' => array(
        'text' => t('Browse available tokens.'),
        'token_types' => array(),
        'global_types' => TRUE,
        'dialog' => TRUE,
        'options' => array(),
        'click_insert' => TRUE,
        'show_restricted' => FALSE,
      ),
    ) + $base,
    'label_machine_name' => array(
      'variables' => array(
        'label' => NULL,
        'machine_name' => NULL,
      ),
    ) + $base,
  ));
}

/**
 * Implements hook_permission().
 */
function system_permission() {
  return array(
    'administer modules' => array(
      'title' => t('Administer modules'),
    ),
    'administer site configuration' => array(
      'title' => t('Administer site configuration'),
      'restrict access' => TRUE,
      'warning' => t('Provides access to a variety of settings/functionality that should generally be restricted to site administrators.'),
    ),
    'administer themes' => array(
      'title' => t('Administer themes'),
    ),
    'administer software updates' => array(
      'title' => t('Administer software updates'),
      'restrict access' => TRUE,
      'warning' => t('Run site updates for Backdrop projects.'),
    ),
    'access administration pages' => array(
      'title' => t('Use the administration pages'),
    ),
    'access site in maintenance mode' => array(
      'title' => t('Use the site in maintenance mode'),
    ),
    'view the administration theme' => array(
      'title' => t('View the administration theme'),
      'description' => config_get('system.core', 'admin_theme') ? '' : t('This is only used when the site is configured to use a separate administration theme on the <a href="@appearance-url">Appearance</a> page.', array('@appearance-url' => url('admin/appearance'))),
    ),
    'access site reports' => array(
      'title' => t('View site reports'),
    ),
    'flush caches' => array(
      'title' => t('Flush caches'),
      'description' => t('Provides access to manually flush caches.'),
    ),
  );
}

/**
 * Implements hook_views_api().
 */
function system_views_api() {
  return array(
    'api' => '3.0',
    'path' => backdrop_get_path('module', 'system') . '/views',
  );
}

/**
 * Implements hook_hook_info().
 */
function system_hook_info() {
  $hooks['token_info'] = array(
    'group' => 'tokens',
  );
  $hooks['token_info_alter'] = array(
    'group' => 'tokens',
  );
  $hooks['tokens'] = array(
    'group' => 'tokens',
  );
  $hooks['tokens_alter'] = array(
    'group' => 'tokens',
  );

  return $hooks;
}

/**
 * Implements hook_element_info().
 */
function system_element_info() {
  // Top level elements.
  $types['form'] = array(
    '#method' => 'post',
    '#action' => request_uri(),
    '#theme_wrappers' => array('form'),
  );
  // By default, we don't want Ajax commands being rendered in the context of an
  // HTML page, so we don't provide defaults for #theme or #theme_wrappers.
  // However, modules can set these properties (for example, to provide an HTML
  // debugging page that displays rather than executes Ajax commands).
  $types['ajax'] = array(
    '#header' => TRUE,
    '#commands' => array(),
    '#error' => NULL,
  );
  $types['head_tag'] = array(
    '#theme' => 'head_tag',
    '#pre_render' => array('backdrop_pre_render_conditional_comments'),
    '#attributes' => array(),
    '#value' => NULL,
  );
  $types['styles'] = array(
    '#items' => array(),
    '#pre_render' => array('backdrop_pre_render_styles'),
    '#group_callback' => 'backdrop_group_css',
    '#aggregate_callback' => 'backdrop_aggregate_css',
  );
  $types['scripts'] = array(
    '#items' => array(),
    '#pre_render' => array('backdrop_pre_render_scripts'),
    '#group_callback' => 'backdrop_group_js',
    '#aggregate_callback' => 'backdrop_aggregate_js',
  );

  // Input elements.
  $types['submit'] = array(
    '#input' => TRUE,
    '#name' => 'op',
    '#button_type' => 'submit',
    '#executes_submit_callback' => TRUE,
    '#limit_validation_errors' => FALSE,
    '#process' => array('ajax_process_form', 'form_process_button'),
    '#theme_wrappers' => array('button'),
  );
  $types['button'] = array(
    '#input' => TRUE,
    '#name' => 'op',
    '#button_type' => 'submit',
    '#executes_submit_callback' => FALSE,
    '#limit_validation_errors' => FALSE,
    '#process' => array('ajax_process_form', 'form_process_button'),
    '#theme_wrappers' => array('button'),
  );
  $types['image_button'] = array(
    '#input' => TRUE,
    '#button_type' => 'submit',
    '#executes_submit_callback' => TRUE,
    '#limit_validation_errors' => FALSE,
    '#process' => array('ajax_process_form', 'form_process_button'),
    '#return_value' => TRUE,
    '#has_garbage_value' => TRUE,
    '#src' => NULL,
    '#theme_wrappers' => array('image_button'),
  );
  $types['textfield'] = array(
    '#input' => TRUE,
    '#size' => 60,
    '#maxlength' => 128,
    '#autocomplete_path' => FALSE,
    '#process' => array('form_process_autocomplete', 'ajax_process_form'),
    '#theme' => 'textfield',
    '#theme_wrappers' => array('form_element'),
  );
  $types['tel'] = array(
    '#input' => TRUE,
    '#size' => 30,
    '#maxlength' => 128,
    '#autocomplete_path' => FALSE,
    '#process' => array('ajax_process_form'),
    '#theme' => 'tel',
    '#theme_wrappers' => array('form_element'),
  );
  $types['email'] = array(
    '#input' => TRUE,
    '#size' => 60,
    '#maxlength' => EMAIL_MAX_LENGTH,
    '#autocomplete_path' => FALSE,
    '#process' => array('ajax_process_form'),
    '#element_validate' => array('form_validate_email'),
    '#theme' => 'email',
    '#theme_wrappers' => array('form_element'),
  );
  $types['url'] = array(
    '#input' => TRUE,
    '#size' => 60,
    '#maxlength' => 255,
    '#autocomplete_path' => FALSE,
    '#process' => array('ajax_process_form'),
    '#element_validate' => array('form_validate_url'),
    '#theme' => 'url',
    '#theme_wrappers' => array('form_element'),
  );
  $types['color'] = array(
    '#input' => TRUE,
    '#process' => array('ajax_process_form'),
    '#element_validate' => array('form_validate_color'),
    '#theme' => 'color',
    '#theme_wrappers' => array('form_element'),
  );
  $types['number'] = array(
    '#input' => TRUE,
    '#step' => 1,
    '#process' => array('ajax_process_form'),
    '#element_validate' => array('form_validate_number'),
    '#theme' => 'number',
    '#theme_wrappers' => array('form_element'),
  );
  $types['range'] = array(
    '#input' => TRUE,
    '#size' => 30,
    '#step' => 1,
    '#min' => 0,
    '#max' => 100,
    '#maxlength' => 128,
    '#process' => array('ajax_process_form'),
    '#element_validate' => array('form_validate_number'),
    '#theme' => 'range',
    '#theme_wrappers' => array('form_element'),
  );
  $types['search'] = array(
    '#input' => TRUE,
    '#size' => 60,
    '#maxlength' => 128,
    '#autocomplete_path' => FALSE,
    '#process' => array('ajax_process_form'),
    '#theme' => 'search',
    '#theme_wrappers' => array('form_element'),
  );
  $types['machine_name'] = array(
    '#input' => TRUE,
    '#default_value' => NULL,
    '#required' => TRUE,
    '#maxlength' => 64,
    '#size' => 60,
    '#autocomplete_path' => FALSE,
    '#process' => array('form_process_machine_name', 'ajax_process_form'),
    '#element_validate' => array('form_validate_machine_name'),
    '#theme' => 'textfield',
    '#theme_wrappers' => array('form_element'),
  );
  $types['password'] = array(
    '#input' => TRUE,
    '#size' => 60,
    '#maxlength' => 128,
    '#process' => array('ajax_process_form'),
    '#theme' => 'password',
    '#theme_wrappers' => array('form_element'),
    '#password_strength' => FALSE,
    '#password_toggle' => FALSE,
    '#password_shown' => FALSE,
    '#process' => array('user_form_process_password'),
  );
  $types['password_confirm'] = array(
    '#input' => TRUE,
    '#process' => array('form_process_password_confirm', 'user_form_process_password_confirm'),
    '#theme_wrappers' => array('form_element'),
  );
  $types['textarea'] = array(
    '#input' => TRUE,
    '#cols' => 60,
    '#rows' => 5,
    '#resizable' => 'vertical',
    '#description_display' => 'before',
    '#process' => array('ajax_process_form'),
    '#theme' => 'textarea',
    '#theme_wrappers' => array('form_element'),
  );
  $types['radios'] = array(
    '#input' => TRUE,
    '#description_display' => 'before',
    '#process' => array('form_process_radios'),
    '#theme_wrappers' => array('container__radios'),
    '#pre_render' => array('form_pre_render_conditional_form_element'),
  );
  $types['radio'] = array(
    '#input' => TRUE,
    '#default_value' => NULL,
    '#process' => array('ajax_process_form'),
    '#theme' => 'radio',
    '#theme_wrappers' => array('form_element'),
    '#title_display' => 'after',
  );
  $types['checkboxes'] = array(
    '#input' => TRUE,
    '#description_display' => 'before',
    '#process' => array('form_process_checkboxes'),
    '#theme_wrappers' => array('container__checkboxes'),
    '#pre_render' => array('form_pre_render_conditional_form_element'),
  );
  $types['checkbox'] = array(
    '#input' => TRUE,
    '#return_value' => 1,
    '#theme' => 'checkbox',
    '#process' => array('form_process_checkbox', 'ajax_process_form'),
    '#theme_wrappers' => array('form_element'),
    '#title_display' => 'after',
  );
  $types['select'] = array(
    '#input' => TRUE,
    '#multiple' => FALSE,
    '#process' => array('form_process_select', 'ajax_process_form'),
    '#theme' => 'select',
    '#theme_wrappers' => array('form_element'),
  );
  $types['weight'] = array(
    '#input' => TRUE,
    '#delta' => 10,
    '#default_value' => 0,
    '#process' => array('form_process_weight', 'ajax_process_form'),
  );
  $types['date'] = array(
    '#input' => TRUE,
    '#element_validate' => array('date_validate'),
    '#process' => array('form_process_date'),
    '#theme' => 'date',
    '#theme_wrappers' => array('form_element'),
  );
  $types['html_date'] = array(
    '#input' => TRUE,
    '#element_validate' => array('html_date_validate'),
    '#theme' => 'html_date',
    '#theme_wrappers' => array('form_element'),
    '#value_callback' => 'html_date_or_time_value_callback',
  );
  $types['html_time'] = array(
    '#input' => TRUE,
    '#element_validate' => array('html_time_validate'),
    '#theme' => 'html_time',
    '#theme_wrappers' => array('form_element'),
    '#value_callback' => 'html_date_or_time_value_callback',
  );
  $types['html_datetime'] = array(
    '#input' => TRUE,
    '#element_validate' => array('html_datetime_validate'),
    '#process' => array('form_process_html_datetime'),
    '#theme' => 'html_datetime',
    '#theme_wrappers' => array('form_element'),
  );
  $types['file'] = array(
    '#input' => TRUE,
    '#size' => 60,
    '#theme' => 'file',
    '#theme_wrappers' => array('form_element'),
  );
  $types['tableselect'] = array(
    '#input' => TRUE,
    '#js_select' => TRUE,
    '#multiple' => TRUE,
    '#process' => array('form_process_tableselect'),
    '#options' => array(),
    '#empty' => '',
    '#theme' => 'tableselect',
  );

  // Form structure.
  $types['item'] = array(
    '#markup' => '',
    '#pre_render' => array('backdrop_pre_render_markup'),
    '#theme_wrappers' => array('form_element'),
  );
  $types['hidden'] = array(
    '#input' => TRUE,
    '#process' => array('ajax_process_form'),
    '#theme' => 'hidden',
  );
  $types['value'] = array(
    '#input' => TRUE,
  );
  $types['markup'] = array(
    '#markup' => '',
    '#pre_render' => array('backdrop_pre_render_markup'),
  );
  $types['help'] = array(
    '#markup' => '',
    '#pre_render' => array('backdrop_pre_render_markup'),
    '#theme' => 'help',
  );
  $types['link'] = array(
    '#pre_render' => array('backdrop_pre_render_link', 'backdrop_pre_render_markup'),
  );
  $types['fieldset'] = array(
    '#collapsible' => FALSE,
    '#collapsed' => FALSE,
    '#value' => NULL,
    '#description_display' => 'before',
    '#process' => array('form_process_fieldset', 'ajax_process_form'),
    '#pre_render' => array('form_pre_render_fieldset'),
    '#theme_wrappers' => array('fieldset'),
  );
  $types['vertical_tabs'] = array(
    '#theme_wrappers' => array('vertical_tabs'),
    '#default_tab' => '',
    '#process' => array('form_process_vertical_tabs'),
  );
  $types['dropbutton'] = array(
    '#pre_render' => array('backdrop_pre_render_dropbutton'),
    '#theme' => 'links__dropbutton',
  );
  $types['operations'] = array(
    '#pre_render' => array('backdrop_pre_render_dropbutton'),
    '#theme' => 'links__dropbutton__operations',
  );
  $types['details'] = array(
    '#summary' => NULL,
    '#details' => NULL,
    '#open' => FALSE,
    '#theme_wrappers' => array('details'),
  );
  $types['container'] = array(
    '#theme_wrappers' => array('container'),
    '#process' => array('form_process_container'),
  );
  $types['actions'] = array(
    '#theme_wrappers' => array('container'),
    '#process' => array('form_process_actions', 'form_process_container'),
    '#weight' => 100,
  );

  $types['token'] = array(
    '#input' => TRUE,
    '#theme' => 'hidden',
  );

  return $types;
}

/**
 * Implements hook_menu().
 */
function system_menu() {
  $items['system/files'] = array(
    'title' => 'File download',
    'page callback' => 'file_download',
    'page arguments' => array('private'),
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  $items['system/temporary'] = array(
    'title' => 'Temporary files',
    'page callback' => 'file_download',
    'page arguments' => array('temporary'),
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  $items['system/ajax'] = array(
    'title' => 'AJAX callback',
    'page callback' => 'ajax_form_callback',
    'delivery callback' => 'ajax_deliver',
    'access callback' => TRUE,
    'theme callback' => 'ajax_base_page_theme',
    'type' => MENU_CALLBACK,
    'file path' => 'core/includes',
    'file' => 'form.inc',
  );
  $items['system/timezone'] = array(
    'title' => 'Time zone',
    'page callback' => 'system_timezone',
    'delivery callback' => 'backdrop_json_deliver',
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
    'file' => 'system.admin.inc',
  );
  $items['system/404'] = array(
    'title' => 'Page not found',
    'page callback' => 'system_404',
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  $items['system/403'] = array(
    'title' => 'Access denied',
    'page callback' => 'system_403',
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  $items['path-autocomplete'] = array(
    'title' => 'Path autocomplete',
    'page callback' => 'path_autocomplete',
    'access callback' => 'user_access',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
  );

  $items['admin'] = array(
    'title' => 'Administration',
    'access arguments' => array('access administration pages'),
    'page callback' => 'system_admin_menu_block_page',
    'weight' => 9,
    'menu_name' => 'management',
    'file' => 'system.admin.inc',
  );
  $items['admin/tasks'] = array(
    'title' => 'Tasks',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -20,
  );
  $items['admin/index'] = array(
    'title' => 'Index',
    'page callback' => 'system_admin_index',
    'access arguments' => array('access administration pages'),
    'type' => MENU_LOCAL_TASK,
    'weight' => -18,
    'file' => 'system.admin.inc',
  );

  // Menu items that are basically just menu blocks.
  $items['admin/structure'] = array(
    'title' => 'Structure',
    'icon' => 'stack-fill',
    'description' => 'Administer blocks, content types, menus, etc.',
    'weight' => -2,
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array('access administration pages'),
    'file' => 'system.admin.inc',
  );
  // Appearance.
  $items['admin/appearance'] = array(
    'title' => 'Appearance',
    'icon' => 'palette-fill',
    'description' => 'Select and configure themes.',
    'page callback' => 'system_themes_page',
    'access arguments' => array('administer themes'),
    'weight' => -4,
    'file' => 'system.admin.inc',
  );
  $items['admin/appearance/list'] = array(
    'title' => 'List themes',
    'description' => 'Select and configure themes.',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -1,
    'file' => 'system.admin.inc',
  );
  $items['admin/appearance/enable'] = array(
    'title' => 'Enable theme',
    'page callback' => 'system_theme_enable',
    'access arguments' => array('administer themes'),
    'type' => MENU_CALLBACK,
    'file' => 'system.admin.inc',
  );
  $items['admin/appearance/disable'] = array(
    'title' => 'Disable theme',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('system_theme_disable_confirm'),
    'access arguments' => array('administer themes'),
    'type' => MENU_CALLBACK,
    'file' => 'system.admin.inc',
  );
  $items['admin/appearance/default'] = array(
    'title' => 'Set default theme',
    'page callback' => 'system_theme_default',
    'access arguments' => array('administer themes'),
    'type' => MENU_CALLBACK,
    'file' => 'system.admin.inc',
  );

  foreach (list_themes() as $key => $theme) {
    // Only provide pages for themes with settings.
    if (theme_has_settings($key)) {
      $items['admin/appearance/settings/' . $theme->name] = array(
        'title' => $theme->info['name'] . ' settings',
        'page callback' => 'backdrop_get_form',
        'page arguments' => array('system_theme_settings', $theme->name),
        'access callback' => '_system_themes_access',
        'access arguments' => array($key),
        'file' => 'system.admin.inc',
        'weight' => 20,
      );
    }
  }

  // Modules.
  $items['admin/modules'] = array(
    'title' => 'Functionality',
    'icon' => 'puzzle-piece-fill',
    'description' => 'Install or uninstall modules.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('system_modules'),
    'access arguments' => array('administer modules'),
    'file' => 'system.admin.inc',
    'weight' => -3,
  );
  $items['admin/modules/list'] = array(
    'title' => 'List modules',
    'type' => MENU_DEFAULT_LOCAL_TASK,
  );
  $items['admin/modules/list/confirm'] = array(
    'title' => 'List modules',
    'access arguments' => array('administer modules'),
    'type' => MENU_VISIBLE_IN_BREADCRUMB,
  );
  $items['admin/modules/uninstall'] = array(
    'title' => 'Uninstall modules',
    'page arguments' => array('system_modules_uninstall'),
    'access arguments' => array('administer modules'),
    'type' => MENU_LOCAL_TASK,
    'file' => 'system.admin.inc',
    'weight' => 20,
  );
  $items['admin/modules/uninstall/confirm'] = array(
    'title' => 'Uninstall modules',
    'access arguments' => array('administer modules'),
    'type' => MENU_VISIBLE_IN_BREADCRUMB,
    'file' => 'system.admin.inc',
  );

  // Configuration.
  $items['admin/config'] = array(
    'title' => 'Configuration',
    'icon' => 'gear-fill',
    'description' => 'Administer settings.',
    'page callback' => 'system_admin_config_page',
    'access arguments' => array('access administration pages'),
    'file' => 'system.admin.inc',
  );
  $items['admin/config/administration'] = array(
    'title' => 'Administration',
    'icon' => 'gear',
    'description' => 'Administration tools.',
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array('access administration pages'),
    'file' => 'system.admin.inc',
  );
  // Media settings.
  $items['admin/config/media'] = array(
    'title' => 'Media',
    'icon' => 'image',
    'description' => 'Media tools.',
    'weight' => -10,
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array('access administration pages'),
    'file' => 'system.admin.inc',
  );
  $items['admin/config/media/file-system'] = array(
    'title' => 'File system',
    'description' => 'Tell Backdrop where to store uploaded files and how they are accessed.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('system_file_system_settings'),
    'access arguments' => array('administer site configuration'),
    'weight' => -10,
    'file' => 'system.admin.inc',
  );
  $items['admin/config/media/file-system/transliteration'] = array(
    'title' => 'Transliteration',
    'description' => 'Convert existing file names to US-ASCII.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('system_transliteration_retroactive'),
    'access arguments' => array('administer site configuration'),
    'file' => 'system.admin.inc',
    'type' => MENU_VISIBLE_IN_BREADCRUMB,
  );
  $items['admin/config/media/image-toolkit'] = array(
    'title' => 'Image toolkit',
    'description' => 'Choose which image toolkit to use if you have installed optional toolkits.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('system_image_toolkit_settings'),
    'access arguments' => array('administer site configuration'),
    'weight' => 20,
    'file' => 'system.admin.inc',
  );

  // Service settings.
  $items['admin/config/services'] = array(
    'title' => 'Web services',
    'icon' => 'rss',
    'description' => 'Tools related to web services.',
    'weight' => 0,
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array('access administration pages'),
    'file' => 'system.admin.inc',
  );
  $items['admin/config/services/rss-publishing'] = array(
    'title' => 'RSS publishing',
    'description' => 'Configure the site description, the number of items per feed and whether feeds should be titles/teasers/full-text.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('system_rss_feeds_settings'),
    'access arguments' => array('administer site configuration'),
    'file' => 'system.admin.inc',
  );

  // Development settings.
  $items['admin/config/development'] = array(
    'title' => 'Development',
    'icon' => 'wrench',
    'description' => 'Development tools.',
    'weight' => -10,
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array('access administration pages'),
    'file' => 'system.admin.inc',
  );
  $items['admin/config/development/maintenance'] = array(
    'title' => 'Maintenance mode',
    'description' => 'Take the site offline for maintenance or bring it back online.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('system_site_maintenance_mode'),
    'access arguments' => array('administer site configuration'),
    'file' => 'system.admin.inc',
    'weight' => -10,
  );
  $items['admin/config/development/performance'] = array(
    'title' => 'Performance',
    'description' => 'Enable or disable page caching for anonymous users and set CSS and JS bandwidth optimization options.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('system_performance_settings'),
    'access arguments' => array('administer site configuration'),
    'file' => 'system.admin.inc',
    'weight' => -20,
  );
  $items['admin/config/development/logging'] = array(
    'title' => 'Logging and errors',
    'description' => "Settings for logging and alerts modules. Various modules can route Backdrop's system events to different destinations, such as syslog, database, email, etc.",
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('system_logging_settings'),
    'access arguments' => array('administer site configuration'),
    'file' => 'system.admin.inc',
    'weight' => -15,
  );
  $items['admin/config/development/jquery'] = array(
    'title' => 'jQuery',
    'description' => 'Configure settings related to the jQuery version.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('system_jquery_settings'),
    'access arguments' => array('administer site configuration'),
    'file' => 'system.admin.inc',
    'weight' => -10,
  );
  $items['admin/config/development/utf8mb4-upgrade'] = array(
    'title' => 'Database 4 byte UTF-8 upgrade',
    'description' => 'Upgrades the database to support 4 byte UTF-8 characters such as emoji and mathematical symbols.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('system_utf8mb4_convert_form'),
    'access arguments' => array('administer site configuration'),
    'file' => 'system.admin.inc',
    'type' => MENU_VISIBLE_IN_BREADCRUMB,
  );

  // Regional and date settings.
  $items['admin/config/regional'] = array(
    'title' => 'Regional and language',
    'icon' => 'globe',
    'description' => 'Regional settings, localization and translation.',
    'weight' => -5,
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array('access administration pages'),
    'file' => 'system.admin.inc',
  );
  $items['admin/config/regional/settings'] = array(
    'title' => 'Regional settings',
    'description' => "Settings for the site's default time zone and country.",
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('system_regional_settings'),
    'access arguments' => array('administer site configuration'),
    'weight' => -20,
    'file' => 'system.admin.inc',
  );
  $items['admin/config/regional/date-time'] = array(
    'title' => 'Date and time formats',
    'description' => 'Configure the display of date and time strings.',
    'page callback' => 'system_date_time_formats',
    'access arguments' => array('administer site configuration'),
    'weight' => -9,
    'file' => 'system.admin.inc',
  );
  $items['admin/config/regional/date-time/formats/add'] = array(
    'title' => 'Add date format',
    'description' => 'Allow users to add additional date formats.',
    'type' => MENU_LOCAL_ACTION,
    'page callback' => 'backdrop_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/%system_date_format'] = array(
    'title' => 'Edit date format',
    'page callback' => 'backdrop_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/%system_date_format/edit'] = array(
    'title' => 'Edit',
    'description' => 'Allow users to edit a configured date format.',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
  );
  $items['admin/config/regional/date-time/formats/%system_date_format/delete'] = array(
    'title' => 'Delete date format',
    'description' => 'Allow users to delete a configured date format.',
    'page callback' => 'backdrop_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',
    'page callback' => 'system_date_time_lookup',
    'access arguments' => array('administer site configuration'),
    'type' => MENU_CALLBACK,
    'file' => 'system.admin.inc',
  );

  // Search settings.
  $items['admin/config/search'] = array(
    'title' => 'Search',
    'icon' => 'magnifying-glass',
    'description' => 'Local site search settings.',
    'weight' => -10,
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array('access administration pages'),
    'file' => 'system.admin.inc',
  );

  // System settings.
  $items['admin/config/system'] = array(
    'title' => 'System',
    'icon' => 'hard-drives',
    'description' => 'General system related configuration.',
    'weight' => -20,
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array('access administration pages'),
    'file' => 'system.admin.inc',
  );
  $items['admin/config/system/site-information'] = array(
    'title' => 'Site information',
    'description' => 'Change site name, logo, favicon, slogan, email address, default home page, and number of posts per page, error pages.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('system_site_information_settings'),
    'access arguments' => array('administer site configuration'),
    'file' => 'system.admin.inc',
    'weight' => -20,
  );
  $items['admin/config/system/cron'] = array(
    'title' => 'Cron',
    'description' => 'Manage automatic site maintenance tasks.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('system_cron_settings'),
    'access arguments' => array('administer site configuration'),
    'file' => 'system.admin.inc',
    'weight' => 20,
  );

  // URL handling.
  $items['admin/config/urls'] = array(
    'title' => 'URL handling',
    'icon' => 'link',
    'description' => 'Settings related to URLs including URL aliases and URL redirects.',
    'weight' => -20,
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array('access administration pages'),
    'file' => 'system.admin.inc',
  );
  $items['admin/config/urls/settings'] = array(
    'title' => 'URL settings',
    'description' => 'General URL-related configuration for your site.',
    'page callback' => 'backdrop_get_form',
    'page arguments' => array('system_urls_settings'),
    'access arguments' => array('administer site configuration'),
    'file' => 'system.admin.inc',
  );
  $items['admin/config/urls/settings/check'] = array(
    'title' => 'Clean URL check',
    'page callback' => 'backdrop_json_output',
    'page arguments' => array(array('status' => TRUE)),
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
    'file' => 'system.admin.inc',
  );

  // @deprecated: Remove backwards-compatibility redirect in 2.0.
  $items['admin/config/search/urls'] = array(
    'page callback' => 'system_redirect_deprecated_page',
    'page arguments' => array('admin/config/urls/settings'),
    'access arguments' => array('administer site configuration'),
    'type' => MENU_CALLBACK,
  );
  // @deprecated: Remove backwards-compatibility redirect in 2.0.
  $items['admin/config/search/clean-urls'] = array(
    'page callback' => 'system_redirect_deprecated_page',
    'page arguments' => array('admin/config/urls/settings'),
    'access arguments' => array('administer site configuration'),
    'type' => MENU_CALLBACK,
  );
  // @deprecated: Remove backwards-compatibility redirect in 2.0.
  $items['admin/config/search/urls/check'] = array(
    'page callback' => 'system_redirect_deprecated_page',
    'page arguments' => array('admin/config/urls/settings/check'),
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );

  // Additional categories
  $items['admin/config/content'] = array(
    'title' => 'Content authoring',
    'icon' => 'note-pencil',
    'description' => 'Settings related to formatting and authoring content.',
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array('access administration pages'),
    'file' => 'system.admin.inc',
  );
  $items['admin/config/metadata'] = array(
    'title' => 'Metadata',
    'icon' => 'code',
    'description' => 'Settings related to meta tags, and other data commonly used by search engines.',
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array('access administration pages'),
    'file' => 'system.admin.inc',
  );
  $items['admin/config/user-interface'] = array(
    'title' => 'User interface',
    'icon' => 'app-window',
    'description' => 'Tools that enhance the user interface.',
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array('access administration pages'),
    'file' => 'system.admin.inc',
  );
  $items['admin/config/workflow'] = array(
    'title' => 'Workflow',
    'icon' => 'path',
    'description' => 'Settings related to editorial workflow.',
    'weight' => 5,
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array('access administration pages'),
    'file' => 'system.admin.inc',
  );

  // Reports.
  $items['admin/reports'] = array(
    'title' => 'Reports',
    'icon' => 'info-fill',
    'description' => 'View reports, updates, and errors.',
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array('access site reports'),
    'weight' => 5,
    'file' => 'system.admin.inc',
  );
  $items['admin/reports/status'] = array(
    'title' => 'Status report',
    'description' => "Get a status report about your site's operation and any detected problems.",
    'page callback' => 'system_status',
    'access arguments' => array('access site reports'),
    'weight' => -60,
    'file' => 'system.admin.inc',
  );
  $items['admin/reports/debug'] = array(
    'title' => 'Debug information',
    'description' => 'Get information about the site that can help with support requests and debugging.',
    'page callback' => 'system_debug_info',
    'access arguments' => array('access site reports'),
    'weight' => -50,
    'file' => 'system.admin.inc',
  );
  $items['admin/reports/status/run-cron'] = array(
    'title' => 'Run cron',
    'page callback' => 'system_run_cron',
    'access arguments' => array('administer site configuration'),
    'type' => MENU_CALLBACK,
    'file' => 'system.admin.inc',
  );
  $items['admin/reports/status/php'] = array(
    'title' => 'PHP',
    'page callback' => 'system_php',
    'access arguments' => array('administer site configuration'),
    'type' => MENU_CALLBACK,
    'file' => 'system.admin.inc',
  );

  // Default page for batch operations.
  $items['batch'] = array(
    'page callback' => 'system_batch_page',
    'access callback' => TRUE,
    'theme callback' => '_system_batch_theme',
    'type' => MENU_CALLBACK,
    'file' => 'system.admin.inc',
  );

  // AJAX endpoint for the assembled token tree.
  $items['token/tree'] = array(
    'page callback' => 'system_token_output',
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
    'file' => 'system.pages.inc',
    'theme callback' => 'ajax_base_page_theme',
  );

  // AJAX endpoint for retrieving a token.
  $items['token-browser/token/%'] = array(
    'page callback' => 'system_token_browser',
    'page arguments' => array(2),
    'delivery callback' => 'system_token_browser_output',
    'access callback' => 'system_token_browser_access',
    'file' => 'system.pages.inc',
    'type' => MENU_CALLBACK,
  );

  // Machine names transliteration.
  $items['system/transliterate/%'] = array(
    'page callback' => 'system_transliterate_ajax',
    'page arguments' => array(2),
    'access callback' => 'system_transliterate_ajax_access',
    'type' => MENU_CALLBACK,
    'file' => 'system.admin.inc',
  );

  return $items;
}

/**
 * Theme callback for the default batch page.
 */
function _system_batch_theme() {
  // Retrieve the current state of the batch.
  $batch = &batch_get();
  if (!$batch && isset($_REQUEST['id'])) {
    require_once BACKDROP_ROOT . '/core/includes/batch.inc';
    $batch = batch_load($_REQUEST['id']);
  }
  // Use the same theme as the page that started the batch.
  if (!empty($batch['theme'])) {
    return $batch['theme'];
  }
}

/**
 * Implements hook_page_delivery_callback_alter().
 *
 * Enables the ability to display arbitrary pages as dialogs based on the
 * HTTP request header.
 */
function system_page_delivery_callback_alter(&$delivery_callback, $page_output) {
  // For all ajax.js initiated requests, deliver as JSON.
  if (backdrop_is_ajax()) {
    $delivery_callback = 'ajax_deliver';
  }
  // For links with the data-dialog attribute, deliver as dialog JSON.
  elseif (backdrop_is_dialog()) {
    $delivery_callback = 'ajax_deliver_dialog';
  }
  // If the page response is a set of AJAX commands, deliver as JSON.
  elseif (isset($page_output['#type']) && $page_output['#type'] === 'ajax') {
    $delivery_callback = 'ajax_deliver';
  }
}

/**
 * Implements hook_library_info().
 */
function system_library_info() {
  $system_module_path = backdrop_get_path('module', 'system');

  // Backdrop's Ajax framework.
  $libraries['backdrop.ajax'] = array(
    'title' => 'Backdrop AJAX',
    'version' => BACKDROP_VERSION,
    'js' => array(
      'core/misc/ajax.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'backdrop.progress'),
    ),
  );

  // Backdrop's batch API.
  $libraries['backdrop.batch'] = array(
    'title' => 'Backdrop batch API',
    'version' => BACKDROP_VERSION,
    'js' => array(
      'core/misc/batch.js' => array('group' => JS_DEFAULT, 'cache' => FALSE),
    ),
    'dependencies' => array(
      array('system', 'backdrop.progress'),
    ),
  );

  // Backdrop's progress indicator.
  $libraries['backdrop.progress'] = array(
    'title' => 'Backdrop progress indicator',
    'version' => BACKDROP_VERSION,
    'js' => array(
      'core/misc/progress.js' => array('group' => JS_DEFAULT),
    ),
  );

  // Backdrop's form library.
  $libraries['backdrop.form'] = array(
    'title' => 'Backdrop form library',
    'version' => BACKDROP_VERSION,
    'js' => array(
      'core/misc/form.js' => array('group' => JS_LIBRARY, 'weight' => 1),
    ),
  );

  // Backdrop's dialog component.
  $libraries['backdrop.dialog'] = array(
    'title' => 'Backdrop dialog',
    'version' => BACKDROP_VERSION,
    'js' => array(
      'core/misc/dialog.js' => array('group' => JS_LIBRARY),
    ),
    'css' => array(
      'core/misc/dialog.theme.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'jquery'),
      array('system', 'ui.dialog'),
    ),
  );

  // Backdrop's integration between AJAX and dialogs.
  $libraries['backdrop.dialog.ajax'] = array(
    'title' => 'Backdrop dialog AJAX integration',
    'version' => BACKDROP_VERSION,
    'js' => array(
      'core/misc/dialog.ajax.js' => array('group' => JS_LIBRARY, 'weight' => 3),
    ),
    'dependencies' => array(
      array('system', 'jquery'),
      array('system', 'backdrop.ajax'),
      array('system', 'backdrop.dialog'),
    ),
  );

  // Backdrop's icon API library.
  $libraries['backdrop.icons'] = array(
    'title' => 'Backdrop icons',
    'version' => BACKDROP_VERSION,
    'js' => array(
      'core/misc/icons.js' => array('group' => JS_LIBRARY, 'weight' => -18),
    ),
  );

  // Backdrop's states library.
  $libraries['backdrop.states'] = array(
    'title' => 'Backdrop states',
    'version' => BACKDROP_VERSION,
    'js' => array(
      'core/misc/states.js' => array('group' => JS_LIBRARY, 'weight' => 1),
    ),
  );

  // Backdrop's responsive table API.
  $libraries['backdrop.tableresponsive'] = array(
    'title' => 'Backdrop responsive table API',
    'version' => BACKDROP_VERSION,
    'js' => array(
      'core/misc/tableresponsive.js' => array('group' => JS_LIBRARY),
    ),
    'dependencies' => array(
      array('system', 'jquery.once'),
    ),
  );

  // Backdrop's collapsible fieldset.
  $libraries['backdrop.collapse'] = array(
    'title' => 'Backdrop collapsible fieldset',
    'version' => BACKDROP_VERSION,
    'js' => array(
      'core/misc/collapse.js' => array('group' => JS_DEFAULT),
    ),
    'dependencies' => array(
      // collapse.js relies on backdropGetSummary in form.js
      array('system', 'backdrop.form'),
    ),
  );

  // Backdrop's autocomplete widget.
  $libraries['backdrop.autocomplete'] = array(
    'title' => 'Backdrop autocomplete',
    'version' => BACKDROP_VERSION,
    'js' => array(
      'core/misc/autocomplete.js' => array('group' => JS_DEFAULT),
    ),
  );

  // Autosubmit for forms.
  $libraries['backdrop.autosubmit'] = array(
    'title' => 'Backdrop autosubmit',
    'version' => BACKDROP_VERSION,
    'js' => array(
      'core/misc/autosubmit.js' => array('group' => JS_DEFAULT),
    ),
  );

  $libraries['backdrop.modules'] = array(
    'title' => 'Modules Filter',
    'version' => BACKDROP_VERSION,
    'js' => array(
      $system_module_path . '/js/modules.js' => array('group' => JS_DEFAULT),
    ),
  );

  $libraries['backdrop.menus'] = array(
    'title' => 'Backdrop menu styles',
    'version' => BACKDROP_VERSION,
    'js' => array(
      $system_module_path . '/js/menus.js' => array('group' => JS_DEFAULT),
    ),
    // CSS is added conditionally below.
  );

  // Announce.
  $libraries['backdrop.announce'] = array(
    'title' => 'Announce',
    'version' => BACKDROP_VERSION,
    'js' => array(
      'core/misc/announce.js' => array('group' => JS_DEFAULT),
    ),
  );

  $libraries['backdrop.menu-toggle'] = array(
    'title' => 'Backdrop menu toggle',
    'version' => BACKDROP_VERSION,
    // CSS is added conditionally below.
  );

  // Add conditional CSS to above libraries.
  $menu_config = config('menu.settings');
  if ($menu_config->get('menu_breakpoint') == 'custom') {
    $libraries['backdrop.menus']['css'] = array(
      $system_module_path . '/css/menu-dropdown.theme.breakpoint.css' => array('group' => CSS_DEFAULT),
      $system_module_path . '/css/menu-dropdown.theme.breakpoint-queries.css' => array(
        'group' => CSS_DEFAULT,
        'media' => 'all and (min-width: ' . $menu_config->get('menu_breakpoint_custom') . ')',
      ),
    );
    $libraries['backdrop.menu-toggle']['css'] = array(
      $system_module_path . '/css/menu-toggle.theme.breakpoint.css' => array('group' => CSS_DEFAULT),
      $system_module_path . '/css/menu-toggle.theme.breakpoint-queries.css' => array(
        'group' => CSS_DEFAULT,
        'media' => 'all and (min-width: ' . $menu_config->get('menu_breakpoint_custom') . ')',
      ),
    );
  }
  else {
    $libraries['backdrop.menus']['css'][$system_module_path . '/css/menu-dropdown.theme.css'] = array('group' => CSS_DEFAULT);
    $libraries['backdrop.menu-toggle']['css'][$system_module_path . '/css/menu-toggle.theme.css'] = array('group' => CSS_DEFAULT);
  }

  // Dismiss buttons.
  $libraries['backdrop.dismiss'] = array(
    'title' => 'Dismiss buttons',
    'version' => BACKDROP_VERSION,
    'js' => array(
      'core/misc/dismiss.js' => array('group' => JS_DEFAULT),
    ),
  );

  // jQuery.
  $libraries['jquery'] = array(
    'title' => 'jQuery',
    'website' => 'http://jquery.com',
    'version' => '3.7.1',
    'js' => array(
      'core/misc/jquery.js' => array('group' => JS_LIBRARY, 'weight' => -20),
    ),
  );

  // jQuery Once.
  $libraries['jquery.once'] = array(
    'title' => 'jQuery Once (Backdrop fork)',
    'version' => '1.2.6',
    'js' => array(
      'core/misc/jquery.once.js' => array('group' => JS_LIBRARY, 'weight' => -19),
    ),
  );

  // jQuery Form Plugin.
  $libraries['jquery.form'] = array(
    'title' => 'jQuery Form Plugin',
    'website' => 'https://github.com/jquery-form/form',
    'version' => '4.3.0',
    'js' => array(
      'core/misc/jquery.form.js' => array(),
    ),
  );

  // jQuery TimeEntry
  $libraries['jquery.timeentry'] = array(
    'title' => 'jQuery Time Entry Plugin',
    'website' => 'http://keith-wood.name/timeEntry.html',
    'version' => '1.5.2',
    'js' => array(
      'core/misc/jquery.timeentry.js' => array(),
    ),
  );

  // Dropbutton.
  $libraries['backdrop.dropbutton'] = array(
    'title' => 'Dropbutton',
    'version' => BACKDROP_VERSION,
    'js' => array(
      'core/misc/dropbutton.js' => array(),
    ),
    'css' => array(
      'core/misc/dropbutton.css' => array(),
      'core/misc/dropbutton.theme.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'jquery.once'),
    ),
  );

  // Vertical Tabs.
  $libraries['backdrop.vertical-tabs'] = array(
    'title' => 'Vertical Tabs',
    'version' => BACKDROP_VERSION,
    'js' => array(
      'core/misc/vertical-tabs.js' => array(),
    ),
    'css' => array(
      'core/misc/vertical-tabs.css' => array(),
    ),
    'dependencies' => array(
      // Vertical tabs relies on backdropGetSummary in form.js
      array('system', 'backdrop.form'),
    ),
  );

  // Jump menu.
  $libraries['jump-menu'] = array(
    'title' => 'Jump Menu',
    'version' => BACKDROP_VERSION,
    'js' => array(
      $system_module_path . '/js/system.jump-menu.js' => array('group' => JS_DEFAULT),
    ),
  );

  // Farbtastic.
  $libraries['farbtastic'] = array(
    'title' => 'Farbtastic',
    'website' => 'http://code.google.com/p/farbtastic/',
    'version' => '1.2',
    'js' => array(
      'core/misc/farbtastic/farbtastic.js' => array(),
    ),
    'css' => array(
      'core/misc/farbtastic/farbtastic.css' => array(),
    ),
  );

  // SmartMenus.
  $libraries['smartmenus'] = array(
    'title' => 'SmartMenus',
    'website' => 'http://www.smartmenus.org',
    'version' => '1.0.0',
    'css' => array(
      'core/misc/smartmenus/css/sm-core-css.css' => array(
        'group' => CSS_THEME,
        'media' => 'screen',
      ),
    ),
    'js' => array(
      'core/misc/smartmenus/jquery.smartmenus.js' => array(
        'group' => JS_LIBRARY,
      ),
      'core/misc/smartmenus/addons/keyboard/jquery.smartmenus.keyboard.js' => array(
        'group' => JS_LIBRARY,
      ),
    ),
  );

  // OpenSans.
  $libraries['opensans'] = array(
    'title' => 'OpenSans',
    'website' => 'https://fonts.google.com/specimen/Open+Sans',
    'version' => '1.0',
    'css' => array(
      'core/misc/opensans/opensans.css' => array(
        'group' => CSS_THEME,
        'media' => 'screen',
      ),
    ),
  );

  // Cookie.
  $libraries['jquery.cookie'] = array(
    'title' => 'Cookie',
    'website' => 'http://plugins.jquery.com/project/cookie',
    'version' => '1.0',
    'js' => array(
      'core/misc/jquery.cookie.js' => array(),
    ),
  );

  // jQuery UI.
  $libraries['ui'] = array(
    'title' => 'jQuery UI: Core',
    'website' => 'http://jqueryui.com',
    'version' => '1.14.0',
    'js' => array(
      'core/misc/jquery-ui-compat.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -11,
      ),
      'core/misc/ui/jquery.ui.data.min.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -11,
      ),
      'core/misc/ui/jquery.ui.disable-selection.min.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -11,
      ),
      'core/misc/ui/jquery.ui.labels.min.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -11,
      ),
      'core/misc/ui/jquery.ui.scroll-parent.min.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -11,
      ),
      'core/misc/ui/jquery.ui.tabbable.min.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -11,
      ),
      'core/misc/ui/jquery.ui.unique-id.min.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -11,
      ),
      'core/misc/ui/jquery.ui.version.min.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -11,
      ),
      'core/misc/ui/jquery.ui.jquery-patch.min.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -11,
      ),
      'core/misc/ui/jquery.ui.focusable.min.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -11,
      ),
      'core/misc/ui/jquery.ui.form-reset-mixin.min.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -11,
      ),
      'core/misc/ui/jquery.ui.keycode.min.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -11,
      ),
      'core/misc/ui/jquery.ui.plugin.min.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -11,
      ),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.core.css' => array(),
      'core/misc/ui/jquery.ui.theme.css' => array(),
    ),
  );
  $libraries['ui.accordion'] = array(
    'title' => 'jQuery UI: Accordion',
    'website' => 'http://jqueryui.com/accordion/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.accordion.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.accordion.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
    ),
  );
  $libraries['ui.autocomplete'] = array(
    'title' => 'jQuery UI: Autocomplete',
    'website' => 'http://jqueryui.com/autocomplete/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.autocomplete.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.autocomplete.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
      array('system', 'ui.position'),
      array('system', 'ui.menu'),
    ),
  );
  $libraries['ui.button'] = array(
    'title' => 'jQuery UI: Button',
    'website' => 'http://jqueryui.com/button/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.button.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.button.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
    ),
  );
  $libraries['ui.checkboxradio'] = array(
    'title' => 'jQuery UI: Checkbox Radio',
    'website' => 'http://jqueryui.com/checkboxradio/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.checkboxradio.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.checkboxradio.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
    ),
  );
  $libraries['ui.controlgroup'] = array(
    'title' => 'jQuery UI: Control Group',
    'website' => 'http://jqueryui.com/controlgroup/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.controlgroup.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.controlgroup.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
    ),
  );
  $libraries['ui.datepicker'] = array(
    'title' => 'jQuery UI: Date Picker',
    'website' => 'http://jqueryui.com/datepicker/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.datepicker.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.datepicker.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui'),
    ),
  );
  $libraries['ui.dialog'] = array(
    'title' => 'jQuery UI: Dialog',
    'website' => 'http://jqueryui.com/dialog/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.dialog.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.dialog.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
      array('system', 'ui.button'),
      array('system', 'ui.draggable'),
      array('system', 'ui.mouse'),
      array('system', 'ui.position'),
      array('system', 'ui.resizable'),
    ),
  );
  $libraries['ui.draggable'] = array(
    'title' => 'jQuery UI: Draggable',
    'website' => 'http://jqueryui.com/draggable/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.draggable.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.draggable.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
      array('system', 'ui.mouse'),
      array('system', 'ui.touch-punch'),
    ),
  );
  $libraries['ui.droppable'] = array(
    'title' => 'jQuery UI: Droppable',
    'website' => 'http://jqueryui.com/droppable/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.droppable.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
      array('system', 'ui.mouse'),
      array('system', 'ui.draggable'),
    ),
  );
  $libraries['ui.menu'] = array(
    'title' => 'jQuery UI: Menu',
    'website' => 'http://jqueryui.com/menu/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.menu.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.menu.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
      array('system', 'ui.position'),
    ),
  );
  $libraries['ui.mouse'] = array(
    'title' => 'jQuery UI: Mouse',
    'website' => 'http://jqueryui.com/mouse/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.mouse.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
    ),
  );
  $libraries['ui.position'] = array(
    'title' => 'jQuery UI: Position',
    'website' => 'http://jqueryui.com/position/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.position.min.js' => array(),
    ),
  );
  $libraries['ui.progressbar'] = array(
    'title' => 'jQuery UI: Progress Bar',
    'website' => 'http://jqueryui.com/progressbar/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.progressbar.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.progressbar.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
    ),
  );
  $libraries['ui.resizable'] = array(
    'title' => 'jQuery UI: Resizable',
    'website' => 'http://jqueryui.com/resizable/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.resizable.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.resizable.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
      array('system', 'ui.mouse'),
    ),
  );
  $libraries['ui.selectable'] = array(
    'title' => 'jQuery UI: Selectable',
    'website' => 'http://jqueryui.com/selectable/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.selectable.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.selectable.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
      array('system', 'ui.mouse'),
    ),
  );

  $libraries['ui.selectmenu'] = array(
    'title' => 'jQuery UI: Select Menu',
    'website' => 'http://jqueryui.com/selectmenu/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.selectmenu.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.selectmenu.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
      array('system', 'ui.position'),
      array('system', 'ui.menu'),
    ),
  );
  $libraries['ui.slider'] = array(
    'title' => 'jQuery UI: Slider',
    'website' => 'http://jqueryui.com/slider/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.slider.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.slider.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
      array('system', 'ui.mouse'),
    ),
  );
  $libraries['ui.sortable'] = array(
    'title' => 'jQuery UI: Sortable',
    'website' => 'http://jqueryui.com/sortable/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.sortable.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.sortable.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.draggable'),
      array('system', 'ui.droppable'),
    ),
  );
  $libraries['ui.spinner'] = array(
    'title' => 'jQuery UI: Spinner',
    'website' => 'http://jqueryui.com/spinner/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.spinner.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.spinner.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
      array('system', 'ui.button'),
    ),
  );
  $libraries['ui.tabs'] = array(
    'title' => 'jQuery UI: Tabs',
    'website' => 'http://jqueryui.com/tabs/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.tabs.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.tabs.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
    ),
  );
  $libraries['ui.tooltip'] = array(
    'title' => 'jQuery UI: Tooltip',
    'website' => 'http://jqueryui.com/tooltip/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.tooltip.min.js' => array(),
    ),
    'css' => array(
      'core/misc/ui/jquery.ui.tooltip.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
      array('system', 'ui.position'),
    ),
  );
  $libraries['ui.widget'] = array(
    'title' => 'jQuery UI: Widget',
    'website' => 'http://jqueryui.com/widget/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.widget.min.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -10,
      ),
    ),
    'dependencies' => array(
      array('system', 'ui'),
    ),
  );

  // The jQuery Color library was separate from jQuery UI: Effects in version
  // 1.13.0 of jQuery UI. The version used here should be locked to the version
  // shipped with jQuery UI.
  $libraries['jquery.color'] = array(
    'title' => 'jQuery Color',
    'website' => 'https://github.com/jquery/jquery-color',
    'version' => '2.2.0',
    'js' => array(
      'core/misc/jquery.color.js'  => array(
        'group' => JS_LIBRARY,
        'weight' => -9,
      ),
    ),
  );

  $libraries['effects'] = array(
    'title' => 'jQuery UI: Effects',
    'website' => 'http://jqueryui.com/effect/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.effect.min.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -9,
      ),
    ),
    'dependencies' => array(
      array('system', 'jquery.color'),
    ),
  );
  $libraries['effects.blind'] = array(
    'title' => 'jQuery UI: Effects Blind',
    'website' => 'http://jqueryui.com/effect/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.effect-blind.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'effects'),
    ),
  );
  $libraries['effects.bounce'] = array(
    'title' => 'jQuery UI: Effects Bounce',
    'website' => 'http://jqueryui.com/effect/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.effect-bounce.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'effects'),
    ),
  );
  $libraries['effects.clip'] = array(
    'title' => 'jQuery UI: Effects Clip',
    'website' => 'http://jqueryui.com/effect/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.effect-clip.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'effects'),
    ),
  );
  $libraries['effects.drop'] = array(
    'title' => 'jQuery UI: Effects Drop',
    'website' => 'http://jqueryui.com/effect/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.effect-drop.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'effects'),
    ),
  );
  $libraries['effects.explode'] = array(
    'title' => 'jQuery UI: Effects Explode',
    'website' => 'http://jqueryui.com/effect/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.effect-explode.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'effects'),
    ),
  );
  $libraries['effects.fade'] = array(
    'title' => 'jQuery UI: Effects Fade',
    'website' => 'http://jqueryui.com/effect/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.effect-fade.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'effects'),
    ),
  );
  $libraries['effects.fold'] = array(
    'title' => 'jQuery UI: Effects Fold',
    'website' => 'http://jqueryui.com/effect/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.effect-fold.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'effects'),
    ),
  );
  $libraries['effects.highlight'] = array(
    'title' => 'jQuery UI: Effects Highlight',
    'website' => 'http://jqueryui.com/effect/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.effect-highlight.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'effects'),
    ),
  );
  $libraries['effects.puff'] = array(
    'title' => 'jQuery UI: Effects Puff',
    'website' => 'http://jqueryui.com/effect/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.effect-puff.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'effects'),
    ),
  );
  $libraries['effects.pulsate'] = array(
    'title' => 'jQuery UI: Effects Pulsate',
    'website' => 'http://jqueryui.com/effect/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.effect-pulsate.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'effects'),
    ),
  );
  $libraries['effects.scale'] = array(
    'title' => 'jQuery UI: Effects Scale',
    'website' => 'http://jqueryui.com/effect/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.effect-scale.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'effects'),
    ),
  );
  $libraries['effects.shake'] = array(
    'title' => 'jQuery UI: Effects Shake',
    'website' => 'http://jqueryui.com/effect/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.effect-shake.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'effects'),
    ),
  );
  $libraries['effects.scale'] = array(
    'title' => 'jQuery UI: Effects Scale',
    'website' => 'http://jqueryui.com/effect/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.effect-scale.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'effects'),
    ),
  );
  $libraries['effects.slide'] = array(
    'title' => 'jQuery UI: Effects Slide',
    'website' => 'http://jqueryui.com/effect/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.effect-slide.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'effects'),
    ),
  );
  $libraries['effects.transfer'] = array(
    'title' => 'jQuery UI: Effects Transfer',
    'website' => 'http://jqueryui.com/effect/',
    'version' => $libraries['ui']['version'],
    'js' => array(
      'core/misc/ui/jquery.ui.effect-transfer.min.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'effects'),
    ),
  );

  // Touch Punch for jQuery UI touch support.
  $libraries['ui.touch-punch'] = array(
    'title' => 'jQuery UI Touch Punch',
    'website' => 'https://github.com/RWAP/jquery-ui-touch-punch/',
    'version' => '1.1.5',
    'js' => array(
      'core/misc/jquery.ui.touch-punch.js' => array(),
    ),
    'dependencies' => array(
      array('system', 'ui.widget'),
      array('system', 'ui.mouse'),
    ),
  );

  // Tokens.
  $libraries['token'] = array(
    'title' => 'Token behaviors',
    'version' => '1.0',
    'js' => array(
      $system_module_path . '/js/token.js' => array(),
    ),
    'css' => array(
      $system_module_path . '/css/token.css' => array(),
    ),
    'dependencies' => array(
      array('system', 'jquery.treetable'),
      array('system', 'backdrop.ajax'),
    ),
    'icons' => array(
      'caret-down',
    ),
  );

  // jQuery treeTable plugin.
  $libraries['jquery.treetable'] = array(
    'title' => 'jQuery treetable',
    'website' => 'http://plugins.jquery.com/project/treetable',
    'version' => '3.2.0',
    'js' => array(
      $system_module_path . '/js/jquery.treetable.js' => array(),
    ),
    'css' => array(
      $system_module_path . '/css/jquery.treetable.css' => array(),
      $system_module_path . '/css/jquery.treetable.theme.default.css' => array(),
    ),
  );

  return $libraries;
}

/**
 * Implements hook_library_info_alter().
 */
function system_library_info_alter(&$libraries, $module) {
  // Immediately return if not modifying the system libraries.
  if ($module !== 'system') {
    return;
  }
  $config = config('system.core');

  // Don't replace anything if default jQuery should be used.
  if ($config->get('jquery_version') == 'legacy') {
    $libraries['jquery']['version'] = '1.12.4';
    $libraries['jquery']['js'] = array(
      'core/misc/jquery.1.12.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -20,
      ),
      // These include security fixes, so assign a weight that makes them load
      // as soon after jquery.js is loaded as possible.
      'core/misc/jquery-extend-3.4.0.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -19,
      ),
      'core/misc/jquery-html-prefilter-3.5.0.js' => array(
        'group' => JS_LIBRARY,
        'weight' => -19,
      ),
    );
  }

}

/**
 * Implements hook_stream_wrappers().
 */
function system_stream_wrappers() {
  $wrappers = array(
    'public' => array(
      'name' => t('Public files'),
      'class' => 'BackdropPublicStreamWrapper',
      'description' => t('Public local files served by the webserver'),
      'type' => STREAM_WRAPPERS_LOCAL_NORMAL,
    ),
    'temporary' => array(
      'name' => t('Temporary files'),
      'class' => 'BackdropTemporaryStreamWrapper',
      'description' => t('Temporary local files for upload and previews'),
      'type' => STREAM_WRAPPERS_LOCAL_HIDDEN,
    ),
  );

  // Only register the private file stream wrapper if a file path has been set.
  if (config_get('system.core', 'file_private_path')) {
    $wrappers['private'] = array(
      'name' => t('Private files'),
      'class' => 'BackdropPrivateStreamWrapper',
      'description' => t('Private local files served by Backdrop'),
      'type' => STREAM_WRAPPERS_LOCAL_NORMAL,
    );
  }

  return $wrappers;
}

/**
 * Menu item access callback - only admin or enabled themes can be accessed.
 */
function _system_themes_access($theme) {
  return user_access('administer themes') && backdrop_theme_access($theme);
}

/**
 * @defgroup authorize Authorized operations
 * @{
 * Functions to run operations with elevated privileges via authorize.php.
 *
 * Because of the Update manager functionality included in Backdrop core, there
 * is a mechanism for running operations with elevated file system privileges,
 * the top-level authorize.php script. This script runs at a reduced Backdrop
 * bootstrap level so that it is not reliant on the entire site being
 * functional. The operations use a FileTransfer class to manipulate code
 * installed on the system as the user that owns the files, not the user that
 * the httpd is running as.
 *
 * The first setup is to define a callback function that should be authorized
 * to run with the elevated privileges. This callback should take a
 * FileTransfer as its first argument, although you can define an array of
 * other arguments it should be invoked with. The callback should be placed in
 * a separate .inc file that will be included by authorize.php.
 *
 * To run the operation, certain data must be saved into the SESSION, and then
 * the flow of control should be redirected to the authorize.php script. There
 * are two ways to do this, either to call system_authorized_run() directly,
 * or to call system_authorized_init() and then redirect to authorize.php,
 * using the URL from system_authorized_get_url(). Redirecting yourself is
 * necessary when your authorized operation is being triggered by a form
 * submit handler, since calling backdrop_goto() in a submit handler is a bad
 * idea, and you should instead set $form_state['redirect'].
 *
 * Once the SESSION is setup for the operation and the user is redirected to
 * authorize.php, they will be prompted for their connection credentials (core
 * provides FTP and SSH by default, although other connection classes can be
 * added via contributed modules). With valid credentials, authorize.php will
 * instantiate the appropriate FileTransfer object, and then invoke the
 * desired operation passing in that object. The authorize.php script can act
 * as a Batch API processing page, if the operation requires a batch.
 *
 * @see authorize.php
 * @see FileTransfer
 * @see hook_filetransfer_info()
 */

/**
 * Setup a given callback to run via authorize.php with elevated privileges.
 *
 * To use authorize.php, certain variables must be stashed into $_SESSION. This
 * function sets up all the necessary $_SESSION variables. The calling function
 * should then redirect to authorize.php, using the full path returned by
 * system_authorized_get_url(). That initiates the workflow that will eventually
 * lead to the callback being invoked. The callback will be invoked at a low
 * bootstrap level, without all modules being invoked, so it needs to be careful
 * not to assume any code exists. Example (system_authorized_run()):
 * @code
 *   system_authorized_init($callback, $file, $arguments, $page_title);
 *   backdrop_goto(system_authorized_get_url());
 * @endcode
 * Example (update_manager_install_form_submit()):
 * @code
 *  system_authorized_init('installer_authorize_run_install',
 *    backdrop_get_path('module', 'installer') . '/installer.authorize.inc',
 *    $arguments, t('Installer'));
 *  $form_state['redirect'] = system_authorized_get_url();
 * @endcode
 *
 * @param $callback
 *   The name of the function to invoke once the user authorizes the operation.
 * @param $file
 *   The full path to the file where the callback function is implemented.
 * @param $arguments
 *   Optional array of arguments to pass into the callback when it is invoked.
 *   Note that the first argument to the callback is always the FileTransfer
 *   object created by authorize.php when the user authorizes the operation.
 * @param $page_title
 *   Optional string to use as the page title once redirected to authorize.php.
 * @return
 *   Nothing, this function just initializes variables in the user's session.
 */
function system_authorized_init($callback, $file, $arguments = array(), $page_title = NULL) {
  // First, figure out what file transfer backends the site supports, and put
  // all of those in the SESSION so that authorize.php has access to all of
  // them via the class autoloader, even without a full bootstrap.
  $_SESSION['authorize_filetransfer_info'] = backdrop_get_filetransfer_info();

  // Now, define the callback to invoke.
  $_SESSION['authorize_operation'] = array(
    'callback' => $callback,
    'file' => $file,
    'arguments' => $arguments,
  );

  if (isset($page_title)) {
    $_SESSION['authorize_operation']['page_title'] = $page_title;
  }
}

/**
 * Return the URL for the authorize.php script.
 *
 * @param array $options
 *   Optional array of options to pass to url().
 * @return
 *   The full URL to authorize.php, using HTTPS if available.
 *
 * @see system_authorized_init()
 */
function system_authorized_get_url(array $options = array()) {
  global $base_url;
  // Force HTTPS if available, regardless of what the caller specifies.
  $options['https'] = TRUE;
  // We prefix with $base_url so we get a full path even if clean URLs are
  // disabled.
  return url($base_url . '/core/authorize.php', $options);
}

/**
 * Returns the URL for the authorize.php script when it is processing a batch.
 */
function system_authorized_batch_processing_url() {
  return system_authorized_get_url(array('query' => array('batch' => '1')));
}

/**
 * Setup and invoke an operation using authorize.php.
 *
 * @see system_authorized_init()
 */
function system_authorized_run($callback, $file, $arguments = array(), $page_title = NULL) {
  system_authorized_init($callback, $file, $arguments, $page_title);
  backdrop_goto(system_authorized_get_url());
}

/**
 * Use authorize.php to run batch_process().
 *
 * @see batch_process()
 */
function system_authorized_batch_process($redirect_callback = 'backdrop_goto') {
  $finish_url = system_authorized_get_url();
  $process_url = system_authorized_batch_processing_url();
  batch_process($finish_url, $process_url, $redirect_callback);
}

/**
 * @} End of "defgroup authorize".
 */

/**
 * Implements hook_updater_info().
 */
function system_updater_info() {
  return array(
    'core' => array(
      'class' => 'CoreUpdater',
      'name' => t('Update Backdrop core'),
      'weight' => 0,
    ),
    'module' => array(
      'class' => 'ModuleUpdater',
      'name' => t('Update modules'),
      'weight' => 0,
    ),
    'theme' => array(
      'class' => 'ThemeUpdater',
      'name' => t('Update themes'),
      'weight' => 0,
    ),
    'layout' => array(
      'class' => 'LayoutUpdater',
      'name' => t('Update layouts'),
      'weight' => 0,
    ),
  );
}

/**
 * Implements hook_filetransfer_info().
 */
function system_filetransfer_info() {
  $backends = array();

  // This is the default, will be available on most systems.
  if (function_exists('ftp_connect')) {
    $backends['ftp'] = array(
      'title' => t('FTP'),
      'class' => 'FileTransferFTP',
      'file' => 'ftp.inc',
      'file path' => 'core/includes/filetransfer',
      'weight' => 0,
    );
  }

  // SSH2 lib connection is only available if the proper PHP extension is
  // installed.
  if (function_exists('ssh2_connect')) {
    $backends['ssh'] = array(
      'title' => t('SSH'),
      'class' => 'FileTransferSSH',
      'file' => 'ssh.inc',
      'file path' => 'core/includes/filetransfer',
      'weight' => 20,
    );
  }
  return $backends;
}

/**
 * Implements hook_file_presave().
 */
function system_file_presave(File $file) {
  // If an uploaded file had its name altered in system_init() and if
  // the human-readable display name is not being transliterated, restore the
  // original version as the human-readable name before saving. (The
  // transliterated version will still be used in the file URI, which is the
  // only place where it matters.)
  $config = config('system.core');
  if (!empty($_FILES['files']['name']) && $config->get('file_transliterate_uploads') && !$config->get('file_transliterate_uploads_display_name')) {
    $key = array_search($file->filename, $_FILES['files']['name']);
    if ($key !== FALSE && isset($_FILES['files']['orig_name'][$key])) {
      $file->filename = $_FILES['files']['orig_name'][$key];
    }
  }
}

/**
 * Implements hook_init().
 */
function system_init() {
  $path = backdrop_get_path('module', 'system');
  // Add the CSS for this module. These aren't in system.info, because they
  // need to be in the CSS_SYSTEM group rather than the CSS_DEFAULT group.
  backdrop_add_css('core/misc/normalize.css', array('group' => CSS_SYSTEM, 'every_page' => TRUE, 'weight' => -1000));
  backdrop_add_css($path . '/css/system.css', array('group' => CSS_SYSTEM, 'every_page' => TRUE));
  if (path_is_admin(current_path())) {
    backdrop_add_css($path . '/css/system.admin.css', array('group' => CSS_SYSTEM));
  }
  backdrop_add_css($path . '/css/system.theme.css', array('group' => CSS_SYSTEM, 'every_page' => TRUE));
  backdrop_add_css($path . '/css/messages.theme.css', array('group' => CSS_SYSTEM, 'every_page' => TRUE));

  // Ignore replica database servers for this request.
  //
  // In Backdrop's distributed database structure, new data is written to the
  // primary and then propagated to the replica servers. This means there is a
  // lag between when data is written to the primary and when it is available on
  // the replica. At these times, we will want to avoid using a replica server
  // temporarily. For example, if a user posts a new node then we want to
  // disable the replica server for that user temporarily to allow the replica
  // server to catch up. That way, that user will see their changes immediately
  // while for other users we still get the benefits of having a replica server,
  // just with slightly stale data. Code that wants to disable the replica
  // server should use the db_ignore_replica() function to set
  // $_SESSION['ignore_replica_server'] to the timestamp after which the replica
  // can be re-enabled.

  // @todo remove this backwards-compatible session variable wrapper in 2.0.
  // cspell:disable
  if (isset($_SESSION['ignore_slave_server'])) {
    $_SESSION['ignore_replica_server'] = $_SESSION['ignore_slave_server'];
    unset($_SESSION['ignore_slave_server']);
    // cspell:enable
  }

  if (isset($_SESSION['ignore_replica_server'])) {
    if ($_SESSION['ignore_replica_server'] >= REQUEST_TIME) {
      Database::ignoreTarget('default', 'replica');
    }
    else {
      unset($_SESSION['ignore_replica_server']);
    }
  }

  // Add CSS/JS files from module .info files.
  system_add_module_assets();

  // Sanitizes file names during upload.
  if (!empty($_FILES['files']) && config_get('system.core', 'file_transliterate_uploads')) {
    // Figure out language, which is available in $_POST['langcode'] for node
    // forms.
    $langcode = NULL;
    if (!empty($_POST['langcode'])) {
      $languages = language_list();
      if (isset($languages[$_POST['langcode']])) {
        $langcode = $_POST['langcode'];
      }
    }
    foreach ($_FILES['files']['name'] as $field => $filename) {
      include_once BACKDROP_ROOT . '/core/includes/transliteration.inc';
      // Keep a copy of the unaltered file name.
      $_FILES['files']['orig_name'][$field] = $filename;
      $_FILES['files']['name'][$field] = transliteration_clean_filename($filename, $langcode);
    }
  }

}

/**
 * Adds CSS and JavaScript files declared in module .info files.
 */
function system_add_module_assets() {
  foreach (system_get_info('module') as $module => $info) {
    if (!empty($info['stylesheets'])) {
      foreach ($info['stylesheets'] as $media => $stylesheets) {
        foreach ($stylesheets as $stylesheet) {
          backdrop_add_css($stylesheet, array('every_page' => TRUE, 'media' => $media));
        }
      }
    }
    if (!empty($info['scripts'])) {
      foreach ($info['scripts'] as $script) {
        backdrop_add_js($script, array('every_page' => TRUE));
      }
    }
  }
}

/**
 * Implements hook_custom_theme().
 */
function system_custom_theme() {
  if (user_access('view the administration theme') && path_is_admin(current_path())) {
    return config_get('system.core', 'admin_theme');
  }
}

/**
 * Implements hook_form_FORM_ID_alter().
 */
function system_form_user_profile_form_alter(&$form, &$form_state) {
  if (config_get('system.date', 'user_configurable_timezones')) {
    system_user_timezone($form, $form_state);
  }
}

/**
 * Implements hook_form_FORM_ID_alter().
 */
function system_form_user_register_form_alter(&$form, &$form_state) {
  $config = config('system.date');
  if ($config->get('user_configurable_timezones') && $config->get('user_default_timezone') == BACKDROP_USER_TIMEZONE_SELECT) {
    system_user_timezone($form, $form_state);
  }
}

/**
 * Implements hook_user_presave().
 */
function system_user_presave($account) {
  $config = config('system.date');
  if ($config->get('user_configurable_timezones') && empty($account->timezone) && !$config->get('user_default_timezone')) {
    $account->timezone = $config->get('default_timezone');
  }
}

/**
 * Implements hook_user_login().
 */
function system_user_login(&$edit, $account) {
  $config = config('system.date');
  // If the user has a NULL time zone, notify them to set a time zone.
  if (!$account->timezone && $config->get('user_configurable_timezones') && $config->get('user_empty_timezone_message')) {
    backdrop_set_message(t('Configure your <a href="@user-edit">account time zone setting</a>.', array('@user-edit' => url("user/$account->uid/edit", array('query' => backdrop_get_destination(), 'fragment' => 'edit-timezone')))));
  }
}

/**
 * Add the time zone field to the user edit and register forms.
 */
function system_user_timezone(&$form, &$form_state) {
  global $user;

  $account = $form['#user'];
  $form['region_language']['timezone'] = array(
    '#type' => 'select',
    '#title' => t('Time zone'),
    '#default_value' => isset($account->timezone) ? $account->timezone : ($account->uid == $user->uid ? config_get('system.date', 'default_timezone') : ''),
    '#options' => system_time_zones($account->uid != $user->uid),
    '#description' => t("This account's preferred time zone for date and time display throughout the site."),
  );
  if (!isset($account->timezone) && $account->uid == $user->uid && empty($form_state['input']['timezone'])) {
    $form['region_language']['timezone']['#attributes'] = array('class' => array('timezone-detect'));
    backdrop_add_js('core/misc/timezone.js');
  }
}

/**
 * Implements hook_block_info().
 */
function system_block_info() {
  $blocks['main'] = array(
    'info' => t('Main page content'),
    'description' => t('The default content for this page. <strong>This block may be required for this page to work properly.</strong>'),
    'required contexts' => array(
      'overrides_path' => 'overrides_path',
    ),
    'render first' => TRUE,
  );
  $blocks['header'] = array(
    'info' => t('Header block'),
    'description' => t('Contains elements typical of a site header including the site logo, name, slogan, and optionally a navigational menu.'),
  );
  $blocks['breadcrumb'] = array(
    'info' => t('Breadcrumb'),
    'description' => t('A trail of links from the homepage to the current page.'),
    'render last' => TRUE,
  );
  $blocks['powered-by'] = array(
    'info' => t('Powered by Backdrop'),
    'description' => t('Displays a link to <a href="https://backdropcms.org">the Backdrop CMS website</a>.'),
    'weight' => '10',
  );
  $blocks['page_components'] = array(
    'info' => t('Page components'),
    'description' => t('Displays the page title, local task tabs, local actions links, and messages.'),
    'class' => 'PageComponents',
    'render last' => TRUE,
  );
  // System-defined menu blocks. Load customizations from Menu module.
  $all_menus = function_exists('menu_get_menus') ? menu_get_menus() : array();
  foreach (menu_list_system_menus() as $menu_name => $title) {
    $custom_title = isset($all_menus[$menu_name]) ? $all_menus[$menu_name] : $title;
    $blocks[$menu_name] = array(
      // Names from menu_list_system_menus() need to be translated through t().
      'info' => check_plain(t($custom_title)),
      'description' => t('A list of links for the menu: %title.', array('%title' => t($custom_title))),
    );
  }
  return $blocks;
}

/**
 * Implements hook_block_view().
 *
 * Generate a block with a promotional link to BackdropCMS.org and
 * all system menu blocks.
 */
function system_block_view($delta = '', $settings = array()) {
  $block = array();
  switch ($delta) {
    case 'main':
      $router_item = menu_get_item();
      if ($router_item['include_file']) {
        require_once BACKDROP_ROOT . '/' . $router_item['include_file'];
      }
      $block['subject'] = NULL;
      $block['content'] = call_user_func_array($router_item['page_callback'], $router_item['page_arguments']);
      return $block;
    case 'header':
      $block['subject'] = NULL;
      $block['content'] = system_header_block($settings);
      return $block;
    case 'breadcrumb':
      $block['subject'] = NULL;
      $block['content'] = system_breadcrumb_block($settings);
      return $block;
    case 'powered-by':
      $block['subject'] = NULL;
      $block['content'] = theme('system_powered_by');
      return $block;
    default:
      // All system menu blocks.
      $system_menus = menu_list_system_menus();
      if (isset($system_menus[$delta])) {
        module_load_include('inc', 'system', 'system.menu');
        $settings += system_menu_block_defaults($delta);
        $data = system_menu_block_build($settings);
        $block['subject'] = $data['subject'];
        $block['content'] = $data['content'];
        return $block;
      }
      break;
  }
}

/**
 * Implements hook_block_configure().
 */
function system_block_configure($delta, $settings) {
  if ($delta === 'header') {
    return system_header_block_form($settings);
  }
  elseif ($delta === 'breadcrumb') {
    $form['current'] = array(
      '#type' => 'checkbox',
      '#title' => t('Display the current page title as the last breadcrumb'),
      '#default_value' => !empty($settings['current']),
    );
    return $form;
  }
  // System-defined menu blocks.
  foreach (menu_list_system_menus() as $menu_name => $title) {
    if ($delta === $menu_name) {
      module_load_include('inc', 'system', 'system.menu');
      return _system_block_configure($delta, $settings);
    }
  }
}

/**
 * Implements hook_block_save().
 */
function system_block_save($delta, &$edit = array()) {
  if ($delta === 'header') {
    // Clean up all the components so Layout module can save them correctly.
    if (is_array($edit['components']) && !empty($edit['components'])) {
      foreach ($edit['components'] as $key => $value) {
        $edit[$key] = $value;
      }
      unset($edit['components']);
    }
  }
}

/**
 * Implements hook_preprocess_block().
 */
function system_preprocess_block(&$variables) {
  if ($variables['block']->module == 'system') {

    switch ($variables['block']->delta) {
      case 'powered-by':
        $variables['attributes']['role'] = 'complementary';
        break;

      case 'main':
        $variables['classes'] = array_values(array_diff($variables['classes'], array('block', 'block-system-main')));
        break;

      // System menu blocks should get the same class as menu module blocks.
      default:
        if (in_array($variables['block']->delta, array_keys(menu_list_system_menus()))) {
          $variables['attributes']['role'] = 'navigation';
          $variables['classes'][] = 'block-menu';
        }
    }
  }
}

/**
 * Provide a single block on the administration overview page.
 *
 * @param $item
 *   The menu item to be displayed.
 */
function system_admin_menu_block($item) {
  $cache = &backdrop_static(__FUNCTION__, array());
  // If we are calling this function for a menu item that corresponds to a
  // local task (for example, admin/tasks), then we want to retrieve the
  // parent item's child links, not this item's (since this item won't have
  // any).
  if ($item['tab_root'] != $item['path']) {
    $item = menu_get_item($item['tab_root_href']);
  }

  if (!isset($item['mlid'])) {
    $item += db_query("SELECT mlid, menu_name FROM {menu_links} ml WHERE ml.router_path = :path AND module = 'system'", array(':path' => $item['path']))->fetchAssoc();
  }

  if (isset($cache[$item['mlid']])) {
    return $cache[$item['mlid']];
  }

  $content = array();
  $query = db_select('menu_links', 'ml', array('fetch' => PDO::FETCH_ASSOC));
  $query->join('menu_router', 'm', 'm.path = ml.router_path');
  $query
    ->fields('ml')
    // Weight should be taken from {menu_links}, not {menu_router}.
    ->fields('m', array_diff(backdrop_schema_fields_sql('menu_router'), array('weight')))
    ->condition('ml.plid', $item['mlid'])
    ->condition('ml.menu_name', $item['menu_name'])
    ->condition('ml.hidden', 0);

  foreach ($query->execute() as $link) {
    _menu_link_translate($link);
    if ($link['access']) {
      // The link description, either derived from 'description' in
      // hook_menu() or customized via menu module is used as title attribute.
      if (!empty($link['localized_options']['attributes']['title'])) {
        $link['description'] = $link['localized_options']['attributes']['title'];
        unset($link['localized_options']['attributes']['title']);
      }
      // Prepare for sorting as in function _menu_tree_check_access().
      // The weight is offset so it is always positive, with a uniform 5-digits.
      $key = (50000 + $link['weight']) . ' ' . backdrop_strtolower($link['title']) . ' ' . $link['mlid'];
      $content[$key] = $link;
    }
  }
  ksort($content);
  $cache[$item['mlid']] = $content;
  return $content;
}

/**
 * Checks the existence of the directory specified in $form_element.
 *
 * This function is called from the system_settings form to check all core
 * file directories (file_public_path, file_private_path, file_temporary_path).
 *
 * @param $form_element
 *   The form element containing the name of the directory to check.
 */
function system_check_directory($form_element) {
  $directory = $form_element['#value'];
  if (strlen($directory) == 0) {
    return $form_element;
  }

  if (!is_dir($directory) && !backdrop_mkdir($directory, NULL, TRUE)) {
    // If the directory does not exists and cannot be created.
    form_set_error($form_element['#parents'][0], t('The directory %directory does not exist and could not be created.', array('%directory' => $directory)));
    watchdog('file system', 'The directory %directory does not exist and could not be created.', array('%directory' => $directory), WATCHDOG_ERROR);
  }

  if (is_dir($directory) && !is_writable($directory) && !backdrop_chmod($directory)) {
    // If the directory is not writable and cannot be made so.
    form_set_error($form_element['#parents'][0], t('The directory %directory exists but is not writable and could not be made writable.', array('%directory' => $directory)));
    watchdog('file system', 'The directory %directory exists but is not writable and could not be made writable.', array('%directory' => $directory), WATCHDOG_ERROR);
  }
  elseif (is_dir($directory) && backdrop_is_apache()) {
    if ($form_element['#name'] == 'file_public_path') {
      // Create public .htaccess file.
      file_save_htaccess($directory, FALSE);
    }
    else {
      // Create private .htaccess file.
      file_save_htaccess($directory);
    }
  }

  return $form_element;
}

/**
 * Retrieves the current status of an array of files in the system table.
 *
 * @param $files
 *   An array of files to check.
 * @param $type
 *   The type of the files ('module', 'theme', 'layout').
 */
function system_get_files_database(&$files, $type) {
  // Extract current files from database.
  $result = db_query("SELECT filename, name, type, status, schema_version, weight FROM {system} WHERE type = :type", array(':type' => $type));
  foreach ($result as $file) {
    if (isset($files[$file->name]) && is_object($files[$file->name])) {
      $file->uri = $file->filename;
      foreach ($file as $key => $value) {
        if (!isset($files[$file->name]->$key)) {
          $files[$file->name]->$key = $value;
        }
      }
    }
  }
}

/**
 * Updates the records in the system table based on the files array.
 *
 * @param $files
 *   An array of files.
 * @param $type
 *   The type of the files.
 */
function system_update_files_database(&$files, $type) {
  $result = db_query("SELECT * FROM {system} WHERE type = :type", array(':type' => $type));

  // Add all files that need to be deleted to a DatabaseCondition.
  $delete = db_or();
  foreach ($result as $file) {
    if (isset($files[$file->name]) && is_object($files[$file->name])) {
      // Keep the old filename from the database in case the file has moved.
      $old_filename = $file->filename;

      $updated_fields = array();

      // Handle info specially, compare the serialized value.
      $serialized_info = serialize($files[$file->name]->info);
      if ($serialized_info != $file->info) {
        $updated_fields['info'] = $serialized_info;
      }
      unset($file->info);

      // Scan remaining fields to find only the updated values.
      foreach ($file as $key => $value) {
        if (isset($files[$file->name]->$key) && $files[$file->name]->$key != $value) {
          $updated_fields[$key] = $files[$file->name]->$key;
        }
      }

      // Update the record.
      if (count($updated_fields)) {
        db_update('system')
          ->fields($updated_fields)
          ->condition('filename', $old_filename)
          ->execute();
      }

      // Indicate that the file exists already.
      $files[$file->name]->exists = TRUE;
    }
    else {
      // File is not found in file system, so delete record from the system table.
      $delete->condition('filename', $file->filename);
    }
  }

  if (count($delete) > 0) {
    // Delete all missing files from the system table, but only if the plugin
    // has never been installed.
    db_delete('system')
      ->condition($delete)
      ->condition('schema_version', -1)
      ->execute();
  }

  // All remaining files are not in the system table, so we need to add them.
  $query = db_insert('system')->fields(array('filename', 'name', 'type', 'owner', 'info'));
  foreach ($files as &$file) {
    if (isset($file->exists)) {
      unset($file->exists);
    }
    else {
      $query->values(array(
        'filename' => $file->uri,
        'name' => $file->name,
        'type' => $type,
        'owner' => isset($file->owner) ? $file->owner : '',
        'info' => serialize($file->info),
      ));
      $file->type = $type;
      $file->status = 0;
      $file->schema_version = -1;
    }
  }
  $query->execute();

  // If any module or theme was moved to a new location, we need to reset the
  // system_list() cache or we will continue to load the old copy, look for
  // schema updates in the wrong place, etc.
  // We avoid system_list_reset() since this resets the static storage in
  // system_rebuild_module_data(), which itself calls this function.
  backdrop_static_reset('system_list');
  backdrop_static_reset('list_themes');
  cache('bootstrap')->deleteMultiple(array('bootstrap_modules', 'system_list'));
}

/**
 * Returns an array of information about enabled modules or themes.
 *
 * This function returns the information from the {system} table corresponding
 * to the cached contents of the .info file for each active module or theme.
 *
 * @param $type
 *   Either 'module' or 'theme'.
 * @param $name
 *   (optional) The name of a module or theme whose information shall be
 *   returned. If omitted, all records for the provided $type will be returned.
 *   If $name does not exist in the provided $type or is not enabled, an empty
 *   array will be returned.
 *
 * @return
 *   An associative array of module or theme information keyed by name, or only
 *   information for $name, if given. If no records are available, an empty
 *   array is returned.
 *
 * @see system_rebuild_module_data()
 * @see system_rebuild_theme_data()
 */
function system_get_info($type, $name = NULL) {
  $info = array();
  if ($type == 'module') {
    $type = 'module_enabled';
  }
  $list = system_list($type);
  foreach ($list as $short_name => $item) {
    if (!empty($item->status)) {
      $info[$short_name] = $item->info;
    }
  }
  if (isset($name)) {
    return isset($info[$name]) ? $info[$name] : array();
  }
  return $info;
}

/**
 * Helper function to scan and collect module .info data.
 *
 * @return
 *   An associative array of module information.
 */
function _system_rebuild_module_data() {
  // Find module files, recording multiples if they exist.
  $files = backdrop_system_listing('/^' . BACKDROP_PHP_FUNCTION_PATTERN . '\.module$/', 'modules', 'uri', 0);
  $modules = array();
  foreach ($files as $file) {
    if (!isset($modules[$file->name])) {
      $modules[$file->name] = $file;
    }
    // Modules found later in the search take precedence, but record all found.
    $modules[$file->name]->uri = $file->uri;
    $modules[$file->name]->all_uris[] = $file->uri;
  }

  // Include the installation profile in modules that are loaded.
  $profile = backdrop_get_profile();
  $profile_uri = 'profiles/' . $profile . '/' . $profile . '.profile';
  if (file_exists(BACKDROP_ROOT . '/core/profiles/' . $profile . '/' . $profile . '.profile')) {
    $profile_uri = 'core/' . $profile_uri;
  }
  $modules[$profile] = new stdClass();
  $modules[$profile]->name = $profile;
  $modules[$profile]->uri = $profile_uri;
  $modules[$profile]->filename = $profile . '.profile';

  // Installation profile hooks are always executed last.
  $modules[$profile]->weight = 1000;

  // Set defaults for module info.
  $defaults = array(
    'dependencies' => array(),
    'description' => '',
    'package' => 'Other',
    'version' => NULL,
    'php' => BACKDROP_MINIMUM_PHP,
    'files' => array(),
    'bootstrap' => 0,
  );

  // Read info files for each module.
  foreach ($modules as $key => $module) {
    // The module system uses the key 'filename' instead of 'uri' so copy the
    // value so it will be used by the modules system.
    $modules[$key]->filename = $module->uri;

    // Look for the info file.
    $module->info = backdrop_parse_info_file(dirname($module->uri) . '/' . $module->name . '.info');

    // Skip modules that don't provide info.
    if (empty($module->info)) {
      unset($modules[$key]);
      continue;
    }

    // Add the info file modification time, so it becomes available for
    // contributed modules to use for ordering module lists.
    $module->info['mtime'] = filemtime(dirname($module->uri) . '/' . $module->name . '.info');

    // Merge in defaults and save.
    $modules[$key]->info = $module->info + $defaults;

    // The "name" key is required, but to avoid a fatal error in the menu system
    // we set a reasonable default if it is not provided.
    $modules[$key]->info += array('name' => $key);

    // Prefix stylesheets and scripts with module path.
    $path = dirname($module->uri);
    if (isset($module->info['stylesheets'])) {
      $module->info['stylesheets'] = _system_info_add_path($module->info['stylesheets'], $path);
    }
    if (isset($module->info['scripts'])) {
      $module->info['scripts'] = _system_info_add_path($module->info['scripts'], $path);
    }

    // Installation profiles are hidden by default, unless explicitly specified
    // otherwise in the .info file.
    if ($key == $profile && !isset($modules[$key]->info['hidden'])) {
      $modules[$key]->info['hidden'] = TRUE;
    }

    // Apply best guess version information if this is a Git checkout.
    if (empty($modules[$key]->info['version'])) {
      $module_base_path = BACKDROP_ROOT . '/' . preg_replace('!(.*modules/[^/]+).*!', '$1', $module->uri);
      $git_version = FALSE;
      if (file_exists($module_base_path . '/.git/HEAD')) {
        // Branches names are directly in the HEAD file.
        $git_head_contents = trim(file_get_contents($module_base_path . '/.git/HEAD'));
        if (strpos($git_head_contents, 'ref') === 0) {
          $git_version = trim(preg_replace('!^.*refs/heads/(.*)$!', '$1', $git_head_contents));
        }
        // Tags are named by sha1 hash, loop through each tag file to match it.
        elseif (is_dir($module_base_path . '/.git/refs/tags')) {
          $tag_files = file_scan_directory($module_base_path . '/.git/refs/tags', '/.*/', array('key' => 'filename', 'recurse' => FALSE));
          $tag_files = array_reverse($tag_files, TRUE);
          foreach ($tag_files as $tag_name => $tag_file) {
            if (trim(file_get_contents($tag_file->uri)) == $git_head_contents) {
              $git_version = $tag_name;
              break;
            }
          }
        }
        if ($git_version) {
          $git_version = preg_replace('/^' . preg_quote(BACKDROP_CORE_COMPATIBILITY, '/') . '-/', '', $git_version);
          $modules[$key]->info['version'] = $git_version . '-dev';
        }
      }
    }

    // Invoke hook_system_info_alter() to give installed modules a chance to
    // modify the data in the .info files if necessary.
    $type = 'module';
    backdrop_alter('system_info', $modules[$key]->info, $modules[$key], $type);
  }

  if (isset($modules[$profile])) {
    // The installation profile is required, if it's a valid module.
    $modules[$profile]->info['required'] = TRUE;
    // Add a default distribution name if the profile did not provide one. This
    // matches the default value used in install_profile_info().
    if (!isset($modules[$profile]->info['distribution_name'])) {
      $modules[$profile]->info['distribution_name'] = 'Backdrop CMS';
    }
  }

  return $modules;
}

/**
 * Rebuild, save, and return data about all currently available modules.
 *
 * @return
 *   Array of all available modules and their data.
 */
function system_rebuild_module_data() {
  $modules_cache = &backdrop_static(__FUNCTION__);
  // Only rebuild once per request. $modules and $modules_cache cannot be
  // combined into one variable, because the $modules_cache variable is reset by
  // reference from system_list_reset() during the rebuild.
  if (!isset($modules_cache)) {
    $modules = _system_rebuild_module_data();
    ksort($modules);
    system_get_files_database($modules, 'module');
    system_update_files_database($modules, 'module');
    $modules = _module_build_dependencies($modules);
    $modules_cache = $modules;
  }
  return $modules_cache;
}

/**
 * Refresh bootstrap column in the system table.
 *
 * This is called internally by module_enable/disable() to flag modules that
 * implement hooks used during bootstrap, such as hook_boot(). These modules
 * are loaded earlier to invoke the hooks.
 */
function _system_update_bootstrap_status() {
  $bootstrap_modules = array();
  foreach (bootstrap_hooks() as $hook) {
    foreach (module_implements($hook) as $module) {
      $bootstrap_modules[] = $module;
    }
  }
  $query = db_update('system')->fields(array('bootstrap' => 0));
  if ($bootstrap_modules) {
    db_update('system')
      ->fields(array('bootstrap' => 1))
      ->condition('name', $bootstrap_modules, 'IN')
      ->execute();
    $query->condition('name', $bootstrap_modules, 'NOT IN');
  }
  $query->execute();
  // Reset the cached list of bootstrap modules.
  system_list_reset();
}

/**
 * Helper function to scan and collect theme .info data and their engines.
 *
 * @return
 *   An associative array of themes information.
 */
function _system_rebuild_theme_data() {
  // Find themes
  $themes = backdrop_system_listing('/^' . BACKDROP_PHP_FUNCTION_PATTERN . '\.info$/', 'themes');
  // Allow modules to add further themes.
  if ($module_themes = module_invoke_all('system_theme_info')) {
    foreach ($module_themes as $name => $uri) {
      // @see file_scan_directory()
      $themes[$name] = (object) array(
        'uri' => $uri,
        'filename' => pathinfo($uri, PATHINFO_FILENAME),
        'name' => $name,
      );
    }
  }

  // Find theme engines
  $engines = backdrop_system_listing('/^' . BACKDROP_PHP_FUNCTION_PATTERN . '\.engine$/', 'themes/engines');

  // Set defaults for theme info.
  $defaults = array(
    'engine' => 'phptemplate',
    'description' => '',
    'screenshot' => 'screenshot.png',
    'php' => BACKDROP_MINIMUM_PHP,
    'stylesheets' => array(),
    'scripts' => array(),
  );

  $sub_themes = array();
  // Read info files for each theme
  foreach ($themes as $key => $theme) {
    $themes[$key]->filename = $theme->uri;
    $themes[$key]->info = backdrop_parse_info_file($theme->uri) + $defaults;

    // Skip modules or layouts that have been placed in the wrong directory.
    if (isset($themes[$key]->info['type']) && $themes[$key]->info['type'] != 'theme') {
      unset($themes[$key]);
      continue;
    }

    // The "name" key is required, but to avoid a fatal error in the menu system
    // we set a reasonable default if it is not provided.
    $themes[$key]->info += array('name' => $key);

    // Add the info file modification time, so it becomes available for
    // contributed modules to use for ordering theme lists.
    $themes[$key]->info['mtime'] = filemtime($theme->uri);

    // Invoke hook_system_info_alter() to give installed modules a chance to
    // modify the data in the .info files if necessary.
    $type = 'theme';
    backdrop_alter('system_info', $themes[$key]->info, $themes[$key], $type);

    if (!empty($themes[$key]->info['base theme'])) {
      $sub_themes[] = $key;
    }
    if ($themes[$key]->info['engine'] == 'theme') {
      $filename = dirname($themes[$key]->uri) . '/' . $themes[$key]->name . '.theme';
      if (file_exists($filename)) {
        $themes[$key]->owner = $filename;
        $themes[$key]->prefix = $key;
      }
    }
    else {
      $engine = $themes[$key]->info['engine'];
      if (isset($engines[$engine])) {
        $themes[$key]->owner = $engines[$engine]->uri;
        $themes[$key]->prefix = $engines[$engine]->name;
        $themes[$key]->template = TRUE;
      }
    }

    // Prefix stylesheets and scripts with module path.
    $path = dirname($theme->uri);
    $theme->info['stylesheets'] = _system_info_add_path($theme->info['stylesheets'], $path);
    $theme->info['scripts'] = _system_info_add_path($theme->info['scripts'], $path);

    // Give the screenshot proper path information.
    if (!empty($themes[$key]->info['screenshot'])) {
      $themes[$key]->info['screenshot'] = $path . '/' . $themes[$key]->info['screenshot'];
    }
  }

  // Now that we've established all our base themes, go back and fill in data
  // for subthemes.
  foreach ($sub_themes as $key) {
    $themes[$key]->base_themes = backdrop_find_base_themes($themes, $key);
    // Don't proceed if there was a problem with the root base theme.
    if (!current($themes[$key]->base_themes)) {
      continue;
    }
    $base_key = key($themes[$key]->base_themes);
    foreach (array_keys($themes[$key]->base_themes) as $base_theme) {
      $themes[$base_theme]->sub_themes[$key] = $themes[$key]->info['name'];
    }
    // Copy the 'owner' and 'engine' over if the top level theme uses a theme
    // engine.
    if (isset($themes[$base_key]->owner)) {
      if (isset($themes[$base_key]->info['engine'])) {
        $themes[$key]->info['engine'] = $themes[$base_key]->info['engine'];
        $themes[$key]->owner = $themes[$base_key]->owner;
        $themes[$key]->prefix = $themes[$base_key]->prefix;
      }
      else {
        $themes[$key]->prefix = $key;
      }
    }
  }

  return $themes;
}

/**
 * Rebuild, save, and return data about all currently available themes.
 *
 * @return
 *   Array of all available themes and their data.
 */
function system_rebuild_theme_data() {
  $themes = _system_rebuild_theme_data();
  ksort($themes);
  system_get_files_database($themes, 'theme');
  system_update_files_database($themes, 'theme');
  return $themes;
}

/**
 * Implements hook_themes_disabled().
 *
 * Remove the theme settings from config when the theme is disabled.
 */
function system_themes_disabled($theme_list) {
  foreach ($theme_list as $theme_name) {
    if (theme_has_settings($theme_name)) {
      $config = config($theme_name . '.settings');
      if (!$config->isNew()) {
        $config->delete();
      }
    }
  }
}

/**
 * Prefixes all values in an .info file array with a given path.
 *
 * This helper function is mainly used to prefix all array values of an .info
 * file property with a single given path (to the module or theme); e.g., to
 * prefix all values of the 'stylesheets' or 'scripts' properties with the file
 * path to the defining module/theme.
 *
 * @param $info
 *   A nested array of data of an .info file to be processed.
 * @param $path
 *   A file path to prepend to each value in $info.
 *
 * @return
 *   The $info array with prefixed values.
 *
 * @see _system_rebuild_module_data()
 * @see _system_rebuild_theme_data()
 */
function _system_info_add_path($info, $path) {
  foreach ($info as $key => $value) {
    // Recurse into nested values until we reach the deepest level.
    if (is_array($value)) {
      $info[$key] = _system_info_add_path($info[$key], $path);
    }
    // Unset the original value's key and set the new value with prefix, using
    // the original value as key, so original values can still be looked up.
    else {
      unset($info[$key]);
      $info[$value] = $path . '/' . $value;
    }
  }
  return $info;
}

/**
 * Settings form for the header block.
 */
function system_header_block_form($settings) {
  $settings += array(
    'menu' => 'user-menu',
    'logo' => TRUE,
    'site_name' => TRUE,
    'site_slogan' => TRUE,
  );

  $form['menu'] = array(
    '#title' => t('Menu'),
    '#type' => 'select',
    '#options' => menu_get_menus(),
    '#empty_option' => '- ' . t('None') . ' -',
    '#default_value' => $settings['menu'],
  );
  $form['components'] = array(
    '#type' => 'fieldset',
    '#title' => t('Site information'),
    '#description' => t('Show or hide various components of your site header. To change the values of these components, visit the !site_info page.',
      array('!site_info' => l(t('Site information'), 'admin/config/system/site-information'))),
  );
  $form['components']['logo'] = array(
    '#type' => 'checkbox',
    '#title' => t('Logo'),
    '#default_value' => $settings['logo'],
  );
  $form['components']['site_name'] = array(
    '#type' => 'checkbox',
    '#title' => t('Site name'),
    '#default_value' => $settings['site_name'],
  );
  $form['components']['site_slogan'] = array(
    '#type' => 'checkbox',
    '#title' => t('Site slogan'),
    '#default_value' => $settings['site_slogan'],
  );

  return $form;
}

/**
 * Output the content for the header block.
 *
 * @see system_block_view()
 */
function system_header_block($settings) {
  $settings += array(
    'menu' => 'user-menu',
    'logo' => TRUE,
    'site_name' => TRUE,
    'site_slogan' => TRUE,
  );

  $menu = $settings['menu'] ? menu_navigation_links($settings['menu']) : NULL;
  $site_config = config('system.core');
  $variables['logo']        = $settings['logo'] ? backdrop_get_logo() : NULL;
  $variables['logo_attributes'] = $settings['logo'] ? array_diff_key(backdrop_get_logo_info(), array('path' => '')) : array();
  $variables['site_name']   = $settings['site_name'] ? check_plain($site_config->getTranslated('site_name')) : '';
  $variables['site_slogan'] = $settings['site_slogan'] ? filter_xss_admin($site_config->getTranslated('site_slogan')) : '';
  $variables['menu']        = $menu ? theme('links__header_menu', array('links' => $menu)) : NULL;

  return theme('header', $variables);
}

/**
 * Output the content for the breadcrumb block.
 *
 * @see system_block_view()
 */
function system_breadcrumb_block($settings = array()) {
  $crumbs = backdrop_get_breadcrumb();
  if (isset($settings['current']) && $settings['current'] == TRUE) {
    $crumbs[] = '<span aria-current="page">' . backdrop_get_title() . '</span>';
  }

  return theme('breadcrumb', array('breadcrumb' => $crumbs));
}

/**
 * Helper function to sort requirements.
 */
function _system_sort_requirements($a, $b) {
  if (!isset($a['weight'])) {
    if (!isset($b['weight'])) {
      return strcasecmp($a['title'], $b['title']);
    }
    return -$b['weight'];
  }
  return isset($b['weight']) ? $a['weight'] - $b['weight'] : $a['weight'];
}

/**
 * Generates a form array for a confirmation form.
 *
 * This function returns a complete form array for confirming an action. The
 * form contains a confirm button as well as a cancellation link that allows a
 * user to abort the action.
 *
 * If the submit handler for a form that implements confirm_form() is invoked,
 * the user successfully confirmed the action. You should never directly
 * inspect $_POST to see if an action was confirmed.
 *
 * Note - if the parameters $question, $description, $yes, or $no could contain
 * any user input (such as node titles or taxonomy terms), it is the
 * responsibility of the code calling confirm_form() to sanitize them first with
 * a function like check_plain() or filter_xss().
 *
 * @param $form
 *   Additional elements to add to the form. These can be regular form elements,
 *   #value elements, etc., and their values will be available to the submit
 *   handler.
 * @param $question
 *   The question to ask the user (e.g. "Are you sure you want to delete the
 *   block <em>foo</em>?"). The page title will be set to this value.
 * @param $path
 *   The page to go to if the user cancels the action. This can be either:
 *   - A string containing a Backdrop path.
 *   - An associative array with a 'path' key. Additional array values are
 *     passed as the $options parameter to l().
 *   If the 'destination' query parameter is set in the URL when viewing a
 *   confirmation form, that value will be used instead of $path.
 * @param $description
 *   Additional text to display. Defaults to t('This action cannot be undone.').
 * @param $yes
 *   A caption for the button that confirms the action (e.g. "Delete",
 *   "Replace", ...). Defaults to t('Confirm').
 * @param $no
 *   A caption for the link which cancels the action (e.g. "Cancel"). Defaults
 *   to t('Cancel').
 * @param $name
 *   The internal name used to refer to the confirmation item.
 *
 * @return
 *   The form array.
 */
function confirm_form($form, $question, $path, $description = NULL, $yes = NULL, $no = NULL, $name = 'confirm') {
  $description = isset($description) ? $description : t('This action cannot be undone.');

  // Prepare cancel link.
  if (isset($_GET['destination'])) {
    $options = backdrop_parse_url($_GET['destination']);
  }
  elseif (is_array($path)) {
    $options = $path;
  }
  else {
    $options = array('path' => $path);
  }

  backdrop_set_title($question, PASS_THROUGH);

  $form['#attributes']['class'][] = 'confirmation';
  $form['description'] = array('#markup' => $description);
  $form[$name] = array('#type' => 'hidden', '#value' => 1);

  $form['actions'] = array('#type' => 'actions');
  $form['actions']['submit'] = array(
    '#type' => 'submit',
    '#value' => $yes ? $yes : t('Confirm'),
    '#attributes' => array('class' => array('button-danger')),
  );
  $form['actions']['cancel'] = array(
    '#type' => 'link',
    '#title' => $no ? $no : t('Cancel'),
    '#href' => $options['path'],
    '#options' => $options,
  );
  // By default, render the form using theme_confirm_form().
  if (!isset($form['#theme'])) {
    $form['#theme'] = 'confirm_form';
  }
  return $form;
}

/**
 * Generate a jump menu form.
 *
 * A jump menu is a select box and an optional 'go' button which can be removed
 * if JavaScript is in use. Each item is keyed to the href that the button
 * should go to. With JavaScript, the page is immediately redirected. Without
 * javascript, the form is submitted and a backdrop_goto() is given.
 *
 * This can either be used with backdrop_get_form() or directly added to a
 * form. The button provides its own submit handler so by default, other
 * submit handlers will not be called.
 *
 * Do not use #tree = TRUE in jump menu forms or it will be unable to find the
 * proper value.
 *
 * @code
 * $output = backdrop_get_form('system_jump_menu', $targets, $options);
 * @endcode
 *
 * @param $select
 *   An array suitable for use as the #options. The keys will be the direct
 *   URLs that will be jumped to, so you absolutely must encode these using
 *   url() in order for them to work reliably.
 *
 * @param $options
 *   $options may be an array with the following options:
 *   - 'title': The text to display for the #title attribute.
 *   - 'description': The text to display for the #description attribute.
 *   - 'default_value': The text to display for the #default_value attribute.
 *   - 'hide': If TRUE the go button will be set to hide via javascript and
 *     will submit on change.
 *   - 'button': The text to display on the button.
 *   - 'image': If set, an image button will be used instead, and the image
 *     set to this.
 *   - 'inline': If set to TRUE (default) the display will be forced inline.
 */
function system_jump_menu($form, &$form_state, $select, $options = array()) {
  $options += array(
    'button' => t('Go'),
    'choose' => t('- Choose -'),
    'inline' => TRUE,
    'hide' => TRUE,
  );

  $form['#attached']['library'][] = array('system', 'jump-menu');

  if (!empty($options['choose'])) {
    $select = array('' => $options['choose']) + $select;
  }

  $form['jump'] = array(
    '#type' => 'select',
    '#options' => $select,
    '#attributes' => array(
      'class' => array('jump-menu-select'),
    ),
  );

  if (!empty($options['title'])) {
    $form['jump']['#title'] = $options['title'];
  }

  if (!empty($options['description'])) {
    $form['jump']['#description'] = $options['description'];
  }

  if (!empty($options['default_value'])) {
    $form['jump']['#default_value'] = $options['default_value'];
  }

  if (isset($options['image'])) {
    $form['go'] = array(
      '#type' => 'image_button',
      '#src' => $options['image'],
      '#submit' => array('system_jump_menu_submit'),
      '#attributes' => array(
        'class' => array('jump-menu-button'),
      ),
    );
  }
  else {
    $form['go'] = array(
      '#type' => 'submit',
      '#value' => $options['button'],
      '#submit' => array('system_jump_menu_submit'),
      '#attributes' => array(
        'class' => array('jump-menu-button'),
      ),
    );
  }

  if ($options['inline']) {
    $form['jump']['#prefix'] = '<div class="container-inline">';
    $form['go']['#suffix'] = '</div>';
  }

  if ($options['hide']) {
    $form['jump']['#attributes']['class'][] = 'jump-menu-change';
    $form['go']['#attributes']['class'][] = 'jump-menu-hide';
  }

  return $form;
}

/**
 * Submit handler for the jump menu.
 *
 * This is normally only invoked upon submit without javascript enabled.
 */
function system_jump_menu_submit($form, &$form_state) {
  if ($form_state['values']['jump'] === '') {
    // We have nothing to do when the user has not selected any value.
    return;
  }

  // If the path we are redirecting to contains the string :: then treat the
  // the string after the double colon as the path to redirect to.
  // This allows duplicate paths to be used in jump menus for multiple options.
  $redirect_array = explode("::", $form_state['values']['jump']);

  if(isset($redirect_array[1]) && !empty($redirect_array[1])){
    $redirect = $redirect_array[1];
  }
  else {
    $redirect = $form_state['values']['jump'];
  }

  // If the path we are redirecting to starts with the base path (for example,
  // "/some_path/node/1"), we need to strip the base path off before passing it
  // to $form_state['redirect'].
  $base_path = base_path();
  if (strpos($redirect, $base_path) === 0) {
    $redirect = substr($redirect, strlen($base_path));
  }

  // Parse the URL so that query strings and fragments are preserved in the
  // redirect.
  $redirect = backdrop_parse_url($redirect);
  $redirect['path'] = urldecode($redirect['path']);
  $form_state['redirect'] = array($redirect['path'], $redirect);
}

/**
 * Generate a list of tasks offered by a specified module.
 *
 * @param $module
 *   Module name.
 * @param $info
 *   The module's information, as provided by system_get_info().
 *
 * @return
 *   An array of task links.
 */
function system_get_module_admin_tasks($module, $info) {
  $links = &backdrop_static(__FUNCTION__);

  if (!isset($links)) {
    $links = array();
    $query = db_select('menu_links', 'ml', array('fetch' => PDO::FETCH_ASSOC));
    $query->join('menu_router', 'm', 'm.path = ml.router_path');
    $query
      ->fields('ml')
      // Weight should be taken from {menu_links}, not {menu_router}.
      ->fields('m', array_diff(backdrop_schema_fields_sql('menu_router'), array('weight')))
      ->condition('ml.link_path', 'admin/%', 'LIKE')
      ->condition('ml.hidden', 0, '>=')
      ->condition('ml.module', 'system')
      ->condition('m.number_parts', 1, '>')
      ->condition('m.page_callback', 'system_admin_menu_block_page', '<>');
    foreach ($query->execute() as $link) {
      _menu_link_translate($link);
      if ($link['access']) {
        $links[$link['router_path']] = $link;
      }
    }
  }

  $admin_tasks = array();
  $titles = array();
  if ($menu = module_invoke($module, 'menu')) {
    foreach ($menu as $path => $item) {
      if (isset($links[$path])) {
        $task = $links[$path];
        // The link description, either derived from 'description' in
        // hook_menu() or customized via menu module is used as title attribute.
        if (!empty($task['localized_options']['attributes']['title'])) {
          $task['description'] = $task['localized_options']['attributes']['title'];
          unset($task['localized_options']['attributes']['title']);
        }

        // Check the admin tasks for duplicate names. If one is found,
        // append the parent menu item's title to differentiate.
        $duplicate_path = array_search($task['title'], $titles);
        if ($duplicate_path !== FALSE) {
          if ($parent = menu_link_load($task['plid'])) {
            // Append the parent item's title to this task's title.
            $task['title'] = t('@original_title (@parent_title)', array('@original_title' => $task['title'], '@parent_title' => $parent['title']));
          }
          if ($parent = menu_link_load($admin_tasks[$duplicate_path]['plid'])) {
            // Append the parent item's title to the duplicated task's title.
            // We use $links[$duplicate_path] in case there are triplicates.
            $admin_tasks[$duplicate_path]['title'] = t('@original_title (@parent_title)', array('@original_title' => $links[$duplicate_path]['title'], '@parent_title' => $parent['title']));
          }
        }
        else {
          $titles[$path] = $task['title'];
        }

        $admin_tasks[$path] = $task;
      }
    }
  }

  // Append link for permissions.
  if (module_hook($module, 'permission')) {
    $item = menu_get_item('admin/config/people/permissions');
    if (!empty($item['access'])) {
      $item['link_path'] = $item['href'];
      $item['title'] = t('Configure @module permissions', array('@module' => $info['name']));
      unset($item['description']);
      $item['localized_options']['fragment'] = 'module-' . $module;
      $admin_tasks["admin/config/people/permissions#module-$module"] = $item;
    }
  }

  return $admin_tasks;
}

/**
 * Implements hook_cron().
 *
 * Remove older rows from flood and batch table. Remove old temporary files.
 */
function system_cron() {
  // Cleanup the flood.
  db_delete('flood')
    ->condition('expiration', REQUEST_TIME, '<')
    ->execute();

  // Cleanup expired tempstore entries.
  db_delete('tempstore')
    ->condition('expire', REQUEST_TIME, '<')
    ->execute();

  // Remove temporary files that are older than BACKDROP_MAXIMUM_TEMP_FILE_AGE.
  // Use separate placeholders for the status to avoid a bug in some versions
  // of PHP. See http://drupal.org/node/352956.
  $result = db_query('SELECT fid FROM {file_managed} WHERE status <> :permanent AND timestamp < :timestamp', array(
    ':permanent' => FILE_STATUS_PERMANENT,
    ':timestamp' => REQUEST_TIME - BACKDROP_MAXIMUM_TEMP_FILE_AGE
  ));
  foreach ($result as $row) {
    if ($file = file_load($row->fid)) {
      $references = file_usage_list($file);
      if (empty($references)) {
        $file->delete();
      }
      else {
        watchdog('file system', 'Did not delete temporary file "%path" during garbage collection because it is in use by the following modules: %modules.', array('%path' => $file->uri, '%modules' => implode(', ', array_keys($references))), WATCHDOG_INFO);
      }
    }
  }

  // Delete expired cache entries.
  // Avoid invoking hook_flush_cashes() on every cron run because some modules
  // use this hook to perform expensive rebuilding operations (which are only
  // designed to happen on full cache clears), rather than just returning a
  // list of cache tables to be cleared.
  $cache_object = cache_get('system_cache_tables');
  if (empty($cache_object)) {
    $core = array('cache', 'path', 'filter', 'page', 'menu');
    $cache_bins = array_merge(module_invoke_all('flush_caches'), $core);
    cache_set('system_cache_tables', $cache_bins);
  }
  else {
    $cache_bins = $cache_object->data;
  }
  foreach ($cache_bins as $bin) {
    cache($bin)->garbageCollection();
  }

  // Cleanup the batch table and the queue for failed batches.
  db_delete('batch')
    ->condition('timestamp', REQUEST_TIME - 864000, '<')
    ->execute();
  db_delete('queue')
    ->condition('created', REQUEST_TIME - 864000, '<')
    ->condition('name', 'backdrop_batch:%', 'LIKE')
    ->execute();

  // Reset expired items in the default queue implementation table. If that's
  // not used, this will be a no-op.
  db_update('queue')
    ->fields(array(
      'expire' => 0,
    ))
    ->condition('expire', 0, '<>')
    ->condition('expire', REQUEST_TIME, '<')
    ->execute();
}

/**
 * Implements hook_flush_caches().
 */
function system_flush_caches() {
  // Reset the menu static caches.
  menu_reset_static_cache();
}

/**
 * Implements hook_mail().
 */
function system_mail($key, &$message, $params) {
  $context = $params['context'];

  $subject = token_replace($context['subject'], $context);
  $body = token_replace($context['message'], $context);

  $message['subject'] .= str_replace(array("\r", "\n"), '', $subject);
  $message['body'][] = $body;
}

/**
 * Generate an array of time zones and their local time&date.
 *
 * @param $blank
 *   If evaluates true, prepend an empty time zone option to the array.
 */
function system_time_zones($blank = NULL) {
  $zone_list = timezone_identifiers_list();
  $zones = $blank ? array('' => t('- None selected -')) : array();
  foreach ($zone_list as $zone) {
    // Because many time zones exist in PHP only for backward compatibility
    // reasons and should not be used, the list is filtered by a regular
    // expression.
    if (preg_match('!^((Africa|America|Antarctica|Arctic|Asia|Atlantic|Australia|Europe|Indian|Pacific)/|UTC$)!', $zone)) {
      $zones[$zone] = t('@zone: @date', array('@zone' => t(str_replace('_', ' ', $zone)), '@date' => format_date(REQUEST_TIME, 'custom', config_get('system.date', 'formats.long.pattern.php') . ' O', $zone)));
    }
  }
  // Sort the translated time zones alphabetically.
  asort($zones);
  return $zones;
}

/**
 * Checks whether the server is capable of issuing HTTP requests.
 *
 * The function sets the backdrop_http_request_fail system variable to TRUE if
 * backdrop_http_request() does not work and then the system status report page
 * will contain an error.
 *
 * Note that this check was never 100% reliable. On some web servers, it would
 * return FALSE even if external requests were allowed. Use of this function
 * has been deprecated and it will be removed in Backdrop 2.0.
 *
 * @return
 *  TRUE if this installation can issue HTTP requests.
 *
 * @deprecated since 1.3.1
 */
function system_check_http_request() {
   watchdog_deprecated_function('system', __FUNCTION__);
  // Try to get the content of the home page via backdrop_http_request().
  $result = backdrop_http_request(url('', array('absolute' => TRUE)), array('max_redirects' => 0, 'timeout' => 10));
  // We only care that we get a http response - this means that Backdrop
  // can make a http request.
  $works = isset($result->code) && ($result->code >= 100) && ($result->code < 600);
  return $works;
}

/**
 * Menu callback; Retrieve a JSON object containing a suggested time zone name.
 */
function system_timezone($abbreviation = '', $offset = -1, $is_daylight_saving_time = NULL) {
  // An abbreviation of "0" passed in the callback arguments should be
  // interpreted as the empty string.
  $abbreviation = $abbreviation ? $abbreviation : '';
  $timezone = timezone_name_from_abbr($abbreviation, intval($offset), $is_daylight_saving_time);
  return array('timezone' => $timezone);
}

/**
 * Implements hook_image_toolkits().
 */
function system_image_toolkits() {
  include_once BACKDROP_ROOT . '/' . backdrop_get_path('module', 'system') . '/image.gd.inc';
  return array(
    'gd' => array(
      'title' => t('GD2 image manipulation toolkit'),
      'available' => function_exists('image_gd_check_settings') && image_gd_check_settings(),
    ),
  );
}

/**
 * Attempts to get a file using backdrop_http_request and to store it locally.
 *
 * @param string $url
 *   The URL of the file to grab.
 * @param string $destination
 *   Stream wrapper URI specifying where the file should be placed. If a
 *   directory path is provided, the file is saved into that directory under
 *   its original name. If the path contains a filename as well, that one will
 *   be used instead.
 *   If this value is omitted, the site's default files scheme will be used,
 *   usually "public://".
 * @param bool $managed
 *   If this is set to TRUE, the file API hooks will be invoked and the file is
 *   registered in the database.
 * @param int $replace
 *   Replace behavior when the destination file already exists:
 *   - FILE_EXISTS_REPLACE: Replace the existing file.
 *   - FILE_EXISTS_RENAME: Append _{incrementing number} until the filename is
 *     unique.
 *   - FILE_EXISTS_ERROR: Do nothing and return FALSE.
 *
 * @return mixed
 *   One of these possibilities:
 *   - If it succeeds and $managed is FALSE, the location where the file was
 *     saved.
 *   - If it succeeds and $managed is TRUE, a FileInterface object which
 *     describes the file.
 *   - If it fails, FALSE.
 */
function system_retrieve_file($url, $destination = NULL, $managed = FALSE, $replace = FILE_EXISTS_RENAME) {
  $parsed_url = parse_url($url);
  if (!isset($destination)) {
    $path = file_build_uri(backdrop_basename($parsed_url['path']));
  }
  else {
    if (is_dir(backdrop_realpath($destination))) {
      // Prevent URIs with triple slashes when glueing parts together.
      $path = str_replace('///', '//', "$destination/") . backdrop_basename($parsed_url['path']);
    }
    else {
      $path = $destination;
    }
  }
  $result = backdrop_http_request($url);
  if ($result->code != 200) {
    backdrop_set_message(t('HTTP error @errorcode occurred when trying to fetch @remote.', array('@errorcode' => $result->code, '@remote' => $url)), 'error');
    return FALSE;
  }
  $local = $managed ? file_save_data($result->data, $path, $replace) : file_unmanaged_save_data($result->data, $path, $replace);
  if (!$local) {
    backdrop_set_message(t('@remote could not be saved to @path.', array('@remote' => $url, '@path' => $path)), 'error');
  }

  return $local;
}

/**
 * Run the automated cron if enabled.
 */
function system_run_automated_cron() {
  // If the site is not fully installed, suppress the automated cron run.
  // Otherwise it could be triggered prematurely by Ajax requests during
  // installation.
  if (($threshold = config('system.core')->get('cron_safe_threshold')) > 0 && state_get('install_task') == 'done') {
    $cron_last = state_get('cron_last', NULL);
    if (!isset($cron_last) || (REQUEST_TIME - $cron_last > $threshold)) {
      backdrop_cron_run();
    }
  }
}

/**
 * Gets the list of defined date formats and attributes.
 *
 * @param $date_format_name
 *   (optional) The date type name.
 *
 * @return
 *   An associative array of date formats. The top-level keys are the
 *   machine-readable names of the date formats. The values are associative
 *   arrays with the following keys:
 *   - name: The string human readable name of the date format.
 *   - pattern: The pattern string as usable by the PHP date() function.
 *
 *   If $date_format_name was defined, only the date formats associated with the
 *   given machine name are returned, in an associative array keyed by format
 *   string.
 */
function system_get_date_formats($date_format_name = NULL) {
  $date_formats = &backdrop_static(__FUNCTION__, array());
  if (empty($date_formats)) {
    $date_formats = config_get('system.date', 'formats');
    if (is_array($date_formats)) {
      foreach ($date_formats as $name => $format) {
        $date_formats[$name]['name'] = $name;
      }
    }
  }

  // Return either the specific format or all formats.
  if (empty($date_format_name)) {
    return $date_formats;
  }
  else {
    return isset($date_formats[$date_format_name]) ? $date_formats[$date_format_name] : FALSE;
  }
}

/**
 * Menu loader function for a date format.
 *
 * @param string $date_format_name
 *   The date type name.
 * @param bool $include_hidden
 *   Include hidden, non-configurable date formats, such as those used by HTML5
 *   date/time elements.
 *
 * @return mixed
 *   The date format array if it exists and is not hidden, FALSE otherwise.
 */
function system_date_format_load($date_format_name, $include_hidden = TRUE) {
  if (($format = system_get_date_formats($date_format_name)) && ($include_hidden || empty($format['hidden']))) {
    return $format;
  }
  return FALSE;
}

/**
 * Saves a date format to the database.
 *
 * @param array $date_format
 *   A date format array containing the following keys:
 *   - name: The machine name of this date format.
 *   - label: The human-readable label for this date format.
 *   - pattern: The pattern string as usable by the PHP date() function.
 *   - langcode: Optional. If multiple languages are available, this specifies
 *     which language the default format is in.
 *   - module: If provided by a module, the name of the providing module. This
 *     will prevent the format from being deleted in the UI.
 *   - hidden: Optional. A boolean indicating whether or not this format should
 *     be configurable from the user interface.
 *
 * @see http://php.net/date
 */
function system_date_format_save($date_format) {
  $format = array(
    'label' => $date_format['label'],
    'pattern' => $date_format['pattern'],
  );
  // Trim empty strings from locale settings.
  if (isset($date_format['locales'])) {
    $date_format['locales'] = array_filter(array_filter($date_format['locales'], 'trim'));
  }
  // Don't save empty defaults.
  foreach (array('module', 'hidden', 'locales') as $key) {
    if (!empty($date_format[$key])) {
      $format[$key] = $date_format[$key];
    }
  }
  config_set('system.date', 'formats.' . $date_format['name'], $format);
  backdrop_static_reset('system_get_date_formats');
}

/**
 * Deletes a date format from the database.
 *
 * @param $date_format_name
 *   The date format ID.
 */
function system_date_format_delete($date_format_name) {
  // Do not allow deletion of module-provided formats.
  $format = system_get_date_formats($date_format_name);
  if (isset($format['module'])) {
    return FALSE;
  }

  $format_id = 'formats.' . $date_format_name;
  config('system.date')->clear($format_id)->save();
  backdrop_static_reset('system_get_date_formats');
}

/**
 * Implements hook_archiver_info().
 */
function system_archiver_info() {
  $archivers['tar'] = array(
    'class' => 'ArchiverTar',
    'extensions' => array('tar', 'tgz', 'tar.gz', 'tar.bz2'),
  );
  if (class_exists('ZipArchive')) {
    $archivers['zip'] = array(
      'class' => 'ArchiverZip',
      'extensions' => array('zip'),
    );
  }
  return $archivers;
}

/**
 * Implements hook_autoload_info().
 */
function system_autoload_info() {
  return array(
    'ArchiverTar' => 'system.archiver.inc',
    'ArchiverZip' => 'system.archiver.inc',
    'DefaultMailSystem' => 'system.mail.inc',
    'TestingMailSystem' => 'system.mail.inc',
    'BackdropQueue' => 'system.queue.inc',
    'BackdropQueueInterface' => 'system.queue.inc',
    'BackdropReliableQueueInterface' => 'system.queue.inc',
    'SystemQueue' => 'system.queue.inc',
    'MemoryQueue' => 'system.queue.inc',
    'Archive_Tar' => 'system.tar.inc',
    'CoreUpdater' => 'system.updater.inc',
    'ModuleUpdater' => 'system.updater.inc',
    'ThemeUpdater' => 'system.updater.inc',
    'LayoutUpdater' => 'system.updater.inc',

    // Blocks.
    'PageComponents' => 'block.page_components.inc',

    // Views handlers.
    'views_handler_filter_system_type' => 'views/views_handler_filter_system_type.inc',
    'views_handler_field_system_info' => 'views/views_handler_field_system_info.inc',
  );
}

/**
 * Implements hook_config_info().
 */
function system_config_info() {
  $prefixes['system.core'] = array(
    'label' => t('System core settings'),
    'group' => t('Configuration'),
  );
  $prefixes['system.authorize'] = array(
    'label' => t('System authorize'),
    'group' => t('Configuration'),
  );
  $prefixes['system.date'] = array(
    'label' => t('System date'),
    'group' => t('Configuration'),
  );
  $prefixes['system.mail'] = array(
    'label' => t('Mail systems'),
    'group' => t('Configuration'),
  );

  // Register config files for all active themes.
  $themes = list_themes();
  foreach ($themes as $theme_name => $theme) {
    // If the theme registers settings, it needs a config file.
    if (theme_has_settings($theme_name) && $theme->status == 1) {
      $prefixes[$theme_name . '.settings'] = array(
        'label' => t('!theme settings', array('!theme' => $theme->info['name'])),
        'group' => t('Configuration'),
      );
    }
  }

  return $prefixes;
}

/**
 * Implements hook_system_info_alter().
 *
 * @deprecated since 1.1
 *   This function should not be necessary in Backdrop 2.0, where modules
 *   built-into core no longer need to be prevented from enabling.
 */
function system_system_info_alter(&$info, $file, $type) {
  if (in_array($file->name, backdrop_merged_modules())) {
    // Set a special flag indicating this module is now in core.
    $info['merged_into_core'] = TRUE;
    // Remove Backdrop core version as a fallback, ensuring it won't be enabled.
    $info['backdrop'] = NULL;
  }
}

/**
 * Menu callback; Returns the standard "Page not found" error page.
 */
function system_404() {
  return '<p>' . t('The requested page "@path" could not be found.', array('@path' => request_uri())) . '</p>';
}

/**
 * Menu callback; Returns the standard "Page not found" error page.
 */
function system_403() {
  return '<p>' . t('You are not authorized to access this page.') . '</p>';
}

/**
 * Menu callback; Autocomplete callback for paths.
 *
 * @param string $string
 *   The string to find matches for.
 */
function path_autocomplete($string = '') {
  $matches = array();
  $match_count = 0;
  $range = 10;

  if ($string) {
    // Get node matches.
    $results = db_select('node')
      ->fields('node', array('nid', 'type', 'title', 'status'))
      ->condition('node.title', '%' . db_like($string) . '%', 'LIKE')
      ->condition('node.status', 1)
      ->addTag('node_access')
      ->orderBy('node.nid', 'DESC')
      ->range(0, $range)
      ->execute();
    foreach ($results as $result) {
      $path = backdrop_get_path_alias('node/' . $result->nid);
      $match = '<span class="autocomplete-suggestion">' . check_plain($result->title) . '</span>';
      $match_description = t('Content: %type', array('%type' => node_type_get_name($result->type)));
      $matches[$path] = $match . ' <span class="autocomplete-description">(' . $match_description . ')</span>';
      $match_count++;
    }

    // Get file matches.
    if (user_access('manage files') && $match_count < $range) {
      $results = db_select('file_managed')
        ->fields('file_managed', array('fid', 'filename', 'uri', 'filemime', 'status', 'type'))
        ->condition('filename', '%' . db_like($string) . '%', 'LIKE')
        ->condition('status', 1)
        ->condition('filemime', 'image%', 'NOT LIKE')
        ->orderBy('fid', 'DESC')
        ->range(0, $range - $match_count)
        ->execute();
      foreach ($results as $result) {
        // If possible, try to make a local path for better portability.
        $absolute_path = parse_url($GLOBALS['base_url'], PHP_URL_PATH) . '/';
        $url = file_create_url($result->uri);
        $path = str_replace($GLOBALS['base_url'] . '/', $absolute_path, $url);
        $match = '<span class="autocomplete-suggestion">' . check_plain($result->filename) . '</span>';
        $match_description = t('File: %type', array('%type' => file_type_get_name($result->type)));
        $matches[$path] = $match . ' <span class="autocomplete-description">(' . $match_description . ')</span>';
        $match_count++;
      }
    }

    // Get user matches.
    if (user_access('access user profiles') && $match_count < $range) {
      $results = db_select('users')
        ->fields('users', array('uid', 'name'))
        ->condition('name', '%' . db_like($string) . '%', 'LIKE')
        ->range(0, $range - $match_count)
        ->orderBy('uid', 'DESC')
        ->execute();
      // We need to load the User object to use user_format_name().
      $uids = array();
      foreach ($results as $result) {
        $uids[] = $result->uid;
      }
      if (!empty($uids)) {
        $users = user_load_multiple($uids);
        foreach ($users as $user) {
          $path = backdrop_get_path_alias('user/' . $user->uid);
          $match = '<span class="autocomplete-suggestion">' . check_plain(user_format_name($user)) . '</span>';
          $match_description = t('User account');
          $matches[$path] = $match . ' <span class="autocomplete-description">(' . $match_description . ')</span>';
          $match_count++;
        }
      }
    }

    // Get taxonomy term matches.
    if (module_exists('taxonomy') && $match_count < $range) {
      $results = db_select('taxonomy_term_data')
        ->fields('taxonomy_term_data', array('tid', 'vocabulary', 'name'))
        ->condition('taxonomy_term_data.name', '%' . db_like($string) . '%', 'LIKE')
        ->addTag('taxonomy_term_access')
        ->range(0, $range - $match_count)
        ->orderBy('taxonomy_term_data.tid', 'DESC')
        ->execute();
      foreach ($results as $result) {
        $path = backdrop_get_path_alias('taxonomy/term/' . $result->tid);
        $match = '<span class="autocomplete-suggestion">' . check_plain($result->name) . '</span>';
        $match_description = t('Taxonomy term: %vocabulary', array('%vocabulary' => taxonomy_vocabulary_load($result->vocabulary)->name));
        $matches[$path] = $match . ' <span class="autocomplete-description">(' . $match_description . ')</span>';
        $match_count++;
      }
    }

    // Get Views page matches.
    if ($match_count < $range) {
      $views = views_get_enabled_views();
      foreach ($views as $view) {
        foreach ($view->display as $display_id => $display) {
          if ($view->access($display_id) && $display->display_plugin == 'page' && !empty($display->display_options['path'])) {
            $path = backdrop_get_path_alias($display->display_options['path']);
            if (!path_is_admin($path)) {
              $view_title = '';
              $found_match = FALSE;
              // Display title.
              if (!empty($display->display_options['title']) && stripos($display->display_options['title'], $string) !== FALSE) {
                $found_match = TRUE;
                $view_title = $display->display_options['title'];
              }
              // Default title.
              elseif (!empty($view->display['default']->display_options['title']) && stripos($view->display['default']->display_options['title'], $string) !== FALSE) {
                $found_match = TRUE;
                $view_title = $view->display['default']->display_options['title'];
              }
              // View name.
              elseif (stripos($view->human_name, $string) !== FALSE) {
                $found_match = TRUE;
                $view_title = $view->human_name;
              }
              if ($found_match) {
                $match = '<span class="autocomplete-suggestion">' . check_plain($view_title) . '</span>';
                $match_description = t('View: %human - %display', array('%human' => $view->human_name, '%display' => $display->display_title));
                $matches[$path] = $match . ' <span class="autocomplete-description">(' . $match_description . ')</span>';
                $match_count++;
              }
            }
          }
          if ($match_count == $range) {
            break 2;
          }
        }
      }
    }

    // Get layout path matches.
    if ($match_count < $range) {
      $menu_items = layout_get_all_configs('menu_item');
      foreach ($menu_items as $menu_item) {
        if ($match_count < $range) {
          $layout_title = '';
          $found_match = FALSE;
          if (!empty($menu_item['menu']['title']) && stripos($menu_item['menu']['title'], $string) !== FALSE) {
            $found_match = TRUE;
            $layout_title = $menu_item['menu']['title'];
          }
          elseif (stripos($menu_item['name'], $string) !== FALSE) {
            $found_match = TRUE;
            $layout_title = $menu_item['name'];
          }
          if ($found_match) {
            $match = '<span class="autocomplete-suggestion">' . check_plain($layout_title) . '</span>';
            $match_description = t('Layout: %display', array('%display' => $menu_item['name']));
            $matches[$menu_item['path']] = $match . ' <span class="autocomplete-description">(' . $match_description . ')</span>';
            $match_count++;
          }
        }
      }
    }

    // Get menu item matches.
    if ($match_count < $range) {
      $results = db_select('menu_links')
        ->fields('menu_links', array('link_title', 'link_path'))
        ->condition('link_title', '%' . db_like($string) . '%', 'LIKE')
        ->condition('link_path', '%' . db_like('%') . '%', 'NOT LIKE')
        ->range(0, $range)
        ->execute();
      foreach ($results as $result) {
        $path = backdrop_get_path_alias($result->link_path);
        if (!isset($matches[$path]) && !path_is_admin($path)) {
          $match = '<span class="autocomplete-suggestion">' . check_plain($result->link_title) . '</span>';
          $match_description = t('Menu item: %path', array('%path' => $path));
          $matches[$path] = $match . ' <span class="autocomplete-description">(' . $match_description . ')</span>';
          $match_count++;
        }
      }
    }
  }

  // Allow modules to alter the matches.
  backdrop_alter('path_autocomplete', $matches, $string);
  backdrop_json_output($matches);
}

/**
 * Menu callback; Redirects a deprecated menu location to a new path.
 *
 * This wrapper around backdrop_goto_deprecated() should be used as the menu
 * callback in hook_menu() when redirecting from an old path to a new one.
 *
 * @param string $path
 *   The path to which the user should be redirected. Because this is intended
 *   to be used as a page callback, the old path is pulled from the current
 *   menu location (the $_GET['q'] variable).
 * @param array $argument_map
 *   If the old path and new path have differing argument orders, this can be
 *   used to map an argument from one position to another. An old path of
 *   "my-module/%key-one/edit/%" could be redirected to
 *   "my-module/configure/%key-one/%" by setting a map such as:
 *    @code
 *    array(
 *      1 => 2
 *      3 => 3
 *    );
 *    @endcode
 *
 *    Note that this map is zero-indexed.
 *
 * @see arg()
 *
 * @since 1.19.0 Function added.
 */
function system_redirect_deprecated_page($path, $argument_map = array()) {
  // The argument map is passed in as old => new. But we need to get the old
  // keys based on the new position in $path. So flip to make retrieving easy.
  $argument_map = array_flip($argument_map);

  // Perform any substitutions in the passed-in path with the current path.
  $parts = explode('/', $path);
  foreach ($parts as $index => $path_part) {
    if (backdrop_substr($path_part, 0, 1) === '%') {
      if (!empty($argument_map)) {
        $parts[$index] = arg($argument_map[$index]);
      }
      else {
        $parts[$index] = arg($index);
      }
    }
  }
  $path = implode('/', $parts);

  backdrop_goto_deprecated($path);
}

/**
 * Implements hook_admin_paths().
 */
function system_admin_paths() {
  $paths = array(
    'admin' => TRUE,
    'admin/*' => TRUE,
    'batch' => TRUE,
    // This page should not be treated as administrative since it outputs its
    // own content (outside of any administration theme).
    'admin/reports/status/php' => FALSE,
  );
  return $paths;
}

/**
 * Implements hook_file_download().
 */
function system_file_download($uri) {
  // If $uri is a path or belongs to a scheme that has . and .. segments removed
  // in file_uri_normalize_dot_segments(), then do not allow such segments now.
  $scheme = file_uri_scheme($uri);
  if (file_stream_wrapper_valid_scheme($scheme)) {
    $target = file_uri_target($uri);
    if ($target !== FALSE) {
      $skip_schemes = config_get('system.core', 'file_not_normalized_schemes');
      if (!in_array($scheme, $skip_schemes)) {
        // If $uri represents a local path, then replace DIRECTORY_SEPARATOR
        // with '/'.
        if (DIRECTORY_SEPARATOR !== '/') {
          $class = file_stream_wrapper_get_class($scheme);
          if (is_subclass_of($class, BackdropLocalStreamWrapper::class)) {
            $uri = str_replace(DIRECTORY_SEPARATOR, '/', $uri);
          }
        }
        $parts = explode('/', $uri);
        foreach ($parts as $part) {
          if ($part === '.' || $part === '..') {
            // Deny path traversal.
            return -1;
          }
        }
      }
    }
  }

  $core_schemes = array('public', 'private', 'temporary');
  $additional_public_schemes = array_diff((array) config_get('system.core', 'file_additional_public_schemes'), $core_schemes);
  if ($additional_public_schemes) {
    $scheme = file_uri_scheme($uri);
    if (in_array($scheme, $additional_public_schemes, TRUE)) {
      return array(
        // Returning any header grants access, and setting the 'Cache-Control'
        // header is appropriate for public files.
        'Cache-Control' => 'public',
      );
    }
  }
}

/**
 * Sets up a form to save information automatically.
 *
 * This function adds a submit handler and a submit button to a form array. The
 * submit function saves all the data in the form.
 *
 * If $form['#config'] is present in the form, the values will be saved to the
 * named settings file (e.g., my_module.settings). If sub-elements or groups of
 * sub-elements have their own '#config' keys, then values of those elements and
 * their children will be saved to that settings file.
 *
 * For example, consider the form:
 *
 * @code
 * $primary_config = config('my_module.settings');
 * $secondary_config = config('my_module.second');
 * $tertiary_config = config('my_module.third');
 * $form = array(
 *   '#config' => 'my_module.settings',
 *   'first_setting' => array(
 *     '#type' => 'textfield',
 *     '#title' => t('First Setting'),
 *     '#default_value' => $primary_config->get('first_setting'),
 *   ),
 *   'second_setting' => array( ... ),
 *
 *   'bonus_fieldset' => array(
 *     '#type' => 'fieldset',
 *     '#title' => t('Secondary Settings'),
 *     '#config' => 'my_module.second',
 *
 *     'bonus_one' => array( ... ),
 *     'bonus_two' => array( ... ),
 *
 *     'bonus_three' => array(
 *       '#type' => 'textfield',
 *       '#default_value' => $tertiary_config->get('bonus_three'),
 *       '#config' => 'my_module.third',
 *     ),
 *   ),
 * );
 * @endcode
 *
 * The top-level '#config' is "my_module.settings". The values of
 * 'first_setting' and 'second_setting' will both be saved to
 * "my_module.settings".
 *
 * The 'bonus_fieldset' has its own '#config' setting, "my_module.second", which
 * overrides the top-level '#config' setting, so 'bonus_one' and 'bonus_two'
 * will be saved to "my_module.second".
 *
 * The 'bonus_three' has its own '#config' setting, "my_module.third", which
 * overrides the one from the fieldset. The value of 'bonus_three' will be
 * saved to the "my_module.third".
 *
 * Modules that implement hook_form_alter() can use the '#config' settings to
 * save their data to their own settings file by setting the '#config' parameter
 * in their elements or fieldsets.
 *
 * If no top-level $form['#config'] value is present, then the values will be
 * saved to variables using variable_set() from the Drupal compatibility layer.
 * This behavior is deprecated and will be remove in Backdrop 2.0.
 *
 * If you need to manipulate the data in a custom manner, you can either put
 * your own submission handler in the form array before calling this function,
 * or just use your own submission handler instead of calling this function.
 *
 * @param $form
 *   An associative array containing the structure of the form.
 *
 * @return
 *   The form structure.
 *
 * @see system_settings_form_submit()
 * @see _system_sort_form_values_by_config()
 *
 * @since 1.6.0 Restored and made compatible with configuration management.
 */
function system_settings_form($form) {
  $form['actions']['#type'] = 'actions';
  $form['actions']['submit'] = array('#type' => 'submit', '#value' => t('Save configuration'));

  if (empty($form['#config']) && !settings_get('backdrop_drupal_compatibility')) {
    backdrop_set_message(t('Drupal compatibility layer is disabled and this form has not been updated to use Backdrop configuration management. Changes will not be saved.'), 'warning');
  }

  if (!empty($_POST) && form_get_errors()) {
    backdrop_set_message(t('The settings have not been saved because of the errors.'), 'error');
  }
  $form['#submit'][] = 'system_settings_form_submit';
  if (!isset($form['#theme'])) {
    $form['#theme'] = 'system_settings_form';
  }
  return $form;
}

/**
 * Form submission handler for system_settings_form().
 *
 * If you want node type configure style handling of your checkboxes,
 * add an array_filter value to your form.
 *
 * @since 1.6.0 Restored and made compatible with configuration management.
 */
function system_settings_form_submit($form, &$form_state) {
  form_state_values_clean($form_state);

  if (!empty($form['#config'])) {
    $configs = _system_sort_form_values_by_config($form, $form_state, $form['#config']);
    foreach ($configs as $bucket => $data) {
      config_set_multiple($bucket, $data);
    }
  }
  else {
    watchdog('form', 'Backdrop 2.0 and later will require forms using system_settings_form() to set $form[\'#config\'].', array(), WATCHDOG_DEPRECATED);
    if (!settings_get('backdrop_drupal_compatibility')) {
      backdrop_set_message(t('Settings not saved: Drupal compatibility layer is disabled and this form has not been updated to use Backdrop configuration management.'), 'error');
      return;
    }

    foreach ($form_state['values'] as $key => $value) {
      if (is_array($value) && isset($form_state['values']['array_filter'])) {
        $value = array_keys(array_filter($value));
      }
      variable_set($key, $value);
    }
  }

  backdrop_set_message(t('The configuration options have been saved.'));
}

/**
 * Sorts the $form_state['values'] array into CMI buckets by $form['#config'].
 *
 * This function recursively searches the form to assign values from
 * $form_state['values'] into specific CMI buckets.  The top of $form must
 * contain a $form['#config'] entry with the name of the default CMI bucket
 * to use.  If an element contains its own $form['#config'] entry, that CMI
 * bucket name will be used for that element and any child elements in the
 * form.
 *
 * @param $form
 *   An associative array containing the structure of a portion of the form.
 * @param &$form_state
 *   A keyed array containing the current state of the form.
 * @param $inherited_bucket
 *   The name of the bucket to use if $form['#config'] is not set.
 * @param $configs
 *   A keyed array that will contain the form values sorted by CMI bucket when
 *   the function returns.  Defaults to an empty array.
 * @return
 *    Returns an array where the keys are the names of the CMI buckets (e.g.,
 *    system.settings) and the values are key => value arrays of the settings
 *    for each bucket.
 */
function _system_sort_form_values_by_config($form, &$form_state, $inherited_bucket, $configs = array()) {
  foreach (element_children($form) as $key) {
    $form_fragment = $form[$key];

    // Specific elements or groups of elements can specify a bucket.
    $bucket = empty($form_fragment['#config']) ? $inherited_bucket : $form_fragment['#config'];
    // Save this element, if the value is present.
    if (array_key_exists($key, $form_state['values'])) {
      $configs[$bucket][$key] = $form_state['values'][$key];
    }
    // Descend into subgroups.
    if (is_array($form_fragment) && count(element_children($form_fragment))) {
      $configs = _system_sort_form_values_by_config($form_fragment, $form_state, $bucket, $configs);
    }
  }
  return $configs;
}

/**
 * Implements hook_admin_bar_cache_info().
 */
function system_admin_bar_cache_info() {
  $caches = array(
    'assets' => t('CSS and JavaScript'),
    'cache' => t('Page and else'),
    'layout' => t('Layout'),
    'menu' => t('Menu'),
    'theme' => t('Theme registry'),
    'token' => t('Token registry'),
  );
  foreach ($caches as $name => $cache) {
    $caches[$name] = array(
      'title' => $cache,
      'callback' => '_admin_bar_flush_cache',
    );
  }
  return $caches;
}

/**
 * Check if theme_debug is enabled, and throw a warning if so.
 */
function system_theme_debug_enabled_warning() {
  $theme_debug_enabled = config_get('system.core', 'theme_debug');
  if ($theme_debug_enabled) {
    backdrop_set_message(t('Theme debugging is enabled. See the <a href="!url">Status report</a> page for more info.', array('!url' => url('admin/reports/status'))), 'warning', FALSE);
  }
}

/**
 * Wrapper around transliteration_get() that handles common clean up on strings.
 *
 * @param string $string
 *   The string to be transliterated.
 * @param array $options
 *   An array of options for further cleanup. This array includes:
 *   - langcode: The language code of the source string.
 *   - replace: The character with which to replace unknown characters in the
 *     string. Defaults to '_'.
 *   - replace_pattern: A pattern for replacing unknown characters with the
 *     "replace" value.
 *   - maxlength: The maximum allowed length of the returned string.
 *
 * @return string
 *   The transliterated and cleaned up string.
 */

function system_transliterate_machine_name($string, $options = array()) {
  include_once BACKDROP_ROOT . '/core/includes/transliteration.inc';
  $defaults = array(
    'langcode' => $GLOBALS['language']->langcode,
    'replace' => '_',
    'replace_pattern' => NULL,
    'maxlength' => NULL,
  );
  $options = array_intersect_key($options, $defaults) + $defaults;

  // Build the default replacement pattern on the given "replace" property.
  if (!isset($options['replace_pattern'])) {
    $options['replace_pattern'] = '[^0-9A-Za-z' . $options['replace'] . ']+';
  }

  $replace = $options['replace'];
  $string = transliteration_get($string, $replace, $options['langcode']);

  // Remove remaining unsafe characters.
  if ($options['replace_pattern']) {
    $string = preg_replace('/' . $options['replace_pattern'] . '/', $options['replace'], $string);
  }
  // Replace whitespace.
  $string = str_replace(' ', $replace, $string);
  // Remove leading and trailing whitespace/unknown characters.
  $string = trim($string, $replace);
  // Collapse multiple consecutive replacement characters.
  $replace_regex = strlen($replace) ? "([$replace])[$replace]+|" : '';
  $string = preg_replace("/{$replace_regex}(_)_+|(\\.)\\.+|(-)-+/", '$1$2$3$4$5', $string);

  // Set maxlength.
  if ($options['maxlength']) {
    $string = substr($string, 0, $options['maxlength']);
  }

  return $string;
}