wp-includes/class-wp-customize-widgets.php

   1 <?php
   2 /**
   3  * Customize Widgets Class
   4  *
   5  * Implements widget management in the Customizer.
   6  *
   7  * @package WordPress
   8  * @subpackage Customize
   9  * @since 3.9.0
  10  */
  11 final class WP_Customize_Widgets {
  12
  13         /**
  14          * WP_Customize_Manager instance.
  15          *
  16          * @since 3.9.0
  17          * @access public
  18          * @var WP_Customize_Manager
  19          */
  20         public $manager;
  21
  22         /**
  23          * All id_bases for widgets defined in core.
  24          *
  25          * @since 3.9.0
  26          * @access protected
  27          * @var array
  28          */
  29         protected $core_widget_id_bases = array(
  30                 'archives', 'calendar', 'categories', 'links', 'meta',
  31                 'nav_menu', 'pages', 'recent-comments', 'recent-posts',
  32                 'rss', 'search', 'tag_cloud', 'text',
  33         );
  34
  35         /**
  36          * @since 3.9.0
  37          * @access protected
  38          * @var
  39          */
  40         protected $_customized;
  41
  42         /**
  43          * @since 3.9.0
  44          * @access protected
  45          * @var array
  46          */
  47         protected $_prepreview_added_filters = array();
  48
  49         /**
  50          * @since 3.9.0
  51          * @access protected
  52          * @var array
  53          */
  54         protected $rendered_sidebars = array();
  55
  56         /**
  57          * @since 3.9.0
  58          * @access protected
  59          * @var array
  60          */
  61         protected $rendered_widgets = array();
  62
  63         /**
  64          * @since 3.9.0
  65          * @access protected
  66          * @var array
  67          */
  68         protected $old_sidebars_widgets = array();
  69
  70         /**
  71          * Initial loader.
  72          *
  73          * @since 3.9.0
  74          * @access public
  75          *
  76          * @param WP_Customize_Manager $manager Customize manager bootstrap instance.
  77          */
  78         public function __construct( $manager ) {
  79                 $this->manager = $manager;
  80
  81                 add_action( 'after_setup_theme',                       array( $this, 'setup_widget_addition_previews' ) );
  82                 add_action( 'wp_loaded',                               array( $this, 'override_sidebars_widgets_for_theme_switch' ) );
  83                 add_action( 'customize_controls_init',                 array( $this, 'customize_controls_init' ) );
  84                 add_action( 'customize_register',                      array( $this, 'schedule_customize_register' ), 1 );
  85                 add_action( 'customize_controls_enqueue_scripts',      array( $this, 'enqueue_scripts' ) );
  86                 add_action( 'customize_controls_print_styles',         array( $this, 'print_styles' ) );
  87                 add_action( 'customize_controls_print_scripts',        array( $this, 'print_scripts' ) );
  88                 add_action( 'customize_controls_print_footer_scripts', array( $this, 'print_footer_scripts' ) );
  89                 add_action( 'customize_controls_print_footer_scripts', array( $this, 'output_widget_control_templates' ) );
  90                 add_action( 'customize_preview_init',                  array( $this, 'customize_preview_init' ) );
  91
  92                 add_action( 'dynamic_sidebar',                         array( $this, 'tally_rendered_widgets' ) );
  93                 add_filter( 'is_active_sidebar',                       array( $this, 'tally_sidebars_via_is_active_sidebar_calls' ), 10, 2 );
  94                 add_filter( 'dynamic_sidebar_has_widgets',             array( $this, 'tally_sidebars_via_dynamic_sidebar_calls' ), 10, 2 );
  95         }
  96
  97         /**
  98          * Get an unslashed post value or return a default.
  99          *
 100          * @since 3.9.0
 101          *
 102          * @access protected
 103          *
 104          * @param string $name    Post value.
 105          * @param mixed  $default Default post value.
 106          * @return mixed Unslashed post value or default value.
 107          */
 108         protected function get_post_value( $name, $default = null ) {
 109                 if ( ! isset( $_POST[ $name ] ) ) {
 110                         return $default;
 111                 }
 112
 113                 return wp_unslash( $_POST[$name] );
 114         }
 115
 116         /**
 117          * Set up widget addition previews.
 118          *
 119          * Since the widgets get registered on 'widgets_init' before the customizer
 120          * settings are set up on 'customize_register', we have to filter the options
 121          * similarly to how the setting previewer will filter the options later.
 122          *
 123          * @since 3.9.0
 124          *
 125          * @access public
 126          */
 127         public function setup_widget_addition_previews() {
 128                 $is_customize_preview = false;
 129
 130                 if ( ! empty( $this->manager ) && ! is_admin() && 'on' === $this->get_post_value( 'wp_customize' ) ) {
 131                         $is_customize_preview = check_ajax_referer( 'preview-customize_' . $this->manager->get_stylesheet(), 'nonce', false );
 132                 }
 133
 134                 $is_ajax_widget_update = false;
 135                 if ( $this->manager->doing_ajax() && 'update-widget' === $this->get_post_value( 'action' ) ) {
 136                         $is_ajax_widget_update = check_ajax_referer( 'update-widget', 'nonce', false );
 137                 }
 138
 139                 $is_ajax_customize_save = false;
 140                 if ( $this->manager->doing_ajax() && 'customize_save' === $this->get_post_value( 'action' ) ) {
 141                         $is_ajax_customize_save = check_ajax_referer( 'save-customize_' . $this->manager->get_stylesheet(), 'nonce', false );
 142                 }
 143
 144                 $is_valid_request = ( $is_ajax_widget_update || $is_customize_preview || $is_ajax_customize_save );
 145                 if ( ! $is_valid_request ) {
 146                         return;
 147                 }
 148
 149                 // Input from customizer preview.
 150                 if ( isset( $_POST['customized'] ) ) {
 151                         $this->_customized = json_decode( $this->get_post_value( 'customized' ), true );
 152                 } else { // Input from ajax widget update request.
 153                         $this->_customized = array();
 154                         $id_base = $this->get_post_value( 'id_base' );
 155                         $widget_number = $this->get_post_value( 'widget_number', false );
 156                         $option_name = 'widget_' . $id_base;
 157                         $this->_customized[ $option_name ] = array();
 158                         if ( preg_match( '/^[0-9]+$/', $widget_number ) ) {
 159                                 $option_name .= '[' . $widget_number . ']';
 160                                 $this->_customized[ $option_name ][ $widget_number ] = array();
 161                         }
 162                 }
 163
 164                 $function = array( $this, 'prepreview_added_sidebars_widgets' );
 165
 166                 $hook = 'option_sidebars_widgets';
 167                 add_filter( $hook, $function );
 168                 $this->_prepreview_added_filters[] = compact( 'hook', 'function' );
 169
 170                 $hook = 'default_option_sidebars_widgets';
 171                 add_filter( $hook, $function );
 172                 $this->_prepreview_added_filters[] = compact( 'hook', 'function' );
 173
 174                 $function = array( $this, 'prepreview_added_widget_instance' );
 175                 foreach ( $this->_customized as $setting_id => $value ) {
 176                         if ( preg_match( '/^(widget_.+?)(?:\[(\d+)\])?$/', $setting_id, $matches ) ) {
 177                                 $option = $matches[1];
 178
 179                                 $hook = sprintf( 'option_%s', $option );
 180                                 if ( ! has_filter( $hook, $function ) ) {
 181                                         add_filter( $hook, $function );
 182                                         $this->_prepreview_added_filters[] = compact( 'hook', 'function' );
 183                                 }
 184
 185                                 $hook = sprintf( 'default_option_%s', $option );
 186                                 if ( ! has_filter( $hook, $function ) ) {
 187                                         add_filter( $hook, $function );
 188                                         $this->_prepreview_added_filters[] = compact( 'hook', 'function' );
 189                                 }
 190
 191                                 /*
 192                                  * Make sure the option is registered so that the update_option()
 193                                  * won't fail due to the filters providing a default value, which
 194                                  * causes the update_option() to get confused.
 195                                  */
 196                                 add_option( $option, array() );
 197                         }
 198                 }
 199         }
 200
 201         /**
 202          * Ensure that newly-added widgets will appear in the widgets_sidebars.
 203          *
 204          * This is necessary because the customizer's setting preview filters
 205          * are added after the widgets_init action, which is too late for the
 206          * widgets to be set up properly.
 207          *
 208          * @since 3.9.0
 209          * @access public
 210          *
 211          * @param array $sidebars_widgets Associative array of sidebars and their widgets.
 212          * @return array Filtered array of sidebars and their widgets.
 213          */
 214         public function prepreview_added_sidebars_widgets( $sidebars_widgets ) {
 215                 foreach ( $this->_customized as $setting_id => $value ) {
 216                         if ( preg_match( '/^sidebars_widgets\[(.+?)\]$/', $setting_id, $matches ) ) {
 217                                 $sidebar_id = $matches[1];
 218                                 $sidebars_widgets[ $sidebar_id ] = $value;
 219                         }
 220                 }
 221                 return $sidebars_widgets;
 222         }
 223
 224         /**
 225          * Ensure newly-added widgets have empty instances so they
 226          * will be recognized.
 227          *
 228          * This is necessary because the customizer's setting preview
 229          * filters are added after the widgets_init action, which is
 230          * too late for the widgets to be set up properly.
 231          *
 232          * @since 3.9.0
 233          * @access public
 234          *
 235          * @param array|bool|mixed $value Widget instance(s), false if open was empty.
 236          * @return array|mixed Widget instance(s) with additions.
 237          */
 238         public function prepreview_added_widget_instance( $value = false ) {
 239                 if ( ! preg_match( '/^(?:default_)?option_(widget_(.+))/', current_filter(), $matches ) ) {
 240                         return $value;
 241                 }
 242                 $id_base = $matches[2];
 243
 244                 foreach ( $this->_customized as $setting_id => $setting ) {
 245                         $parsed_setting_id = $this->parse_widget_setting_id( $setting_id );
 246                         if ( is_wp_error( $parsed_setting_id ) || $id_base !== $parsed_setting_id['id_base'] ) {
 247                                 continue;
 248                         }
 249                         $widget_number = $parsed_setting_id['number'];
 250
 251                         if ( is_null( $widget_number ) ) {
 252                                 // Single widget.
 253                                 if ( false === $value ) {
 254                                         $value = array();
 255                                 }
 256                         } else {
 257                                 // Multi widget.
 258                                 if ( empty( $value ) ) {
 259                                         $value = array( '_multiwidget' => 1 );
 260                                 }
 261                                 if ( ! isset( $value[ $widget_number ] ) ) {
 262                                         $value[ $widget_number ] = array();
 263                                 }
 264                         }
 265                 }
 266
 267                 return $value;
 268         }
 269
 270         /**
 271          * Remove pre-preview filters.
 272          *
 273          * Removes filters added in setup_widget_addition_previews()
 274          * to ensure widgets are populating the options during
 275          * 'widgets_init'.
 276          *
 277          * @since 3.9.0
 278          * @access public
 279          */
 280         public function remove_prepreview_filters() {
 281                 foreach ( $this->_prepreview_added_filters as $prepreview_added_filter ) {
 282                         remove_filter( $prepreview_added_filter['hook'], $prepreview_added_filter['function'] );
 283                 }
 284                 $this->_prepreview_added_filters = array();
 285         }
 286
 287         /**
 288          * Override sidebars_widgets for theme switch.
 289          *
 290          * When switching a theme via the customizer, supply any previously-configured
 291          * sidebars_widgets from the target theme as the initial sidebars_widgets
 292          * setting. Also store the old theme's existing settings so that they can
 293          * be passed along for storing in the sidebars_widgets theme_mod when the
 294          * theme gets switched.
 295          *
 296          * @since 3.9.0
 297          * @access public
 298          */
 299         public function override_sidebars_widgets_for_theme_switch() {
 300                 global $sidebars_widgets;
 301
 302                 if ( $this->manager->doing_ajax() || $this->manager->is_theme_active() ) {
 303                         return;
 304                 }
 305
 306                 $this->old_sidebars_widgets = wp_get_sidebars_widgets();
 307                 add_filter( 'customize_value_old_sidebars_widgets_data', array( $this, 'filter_customize_value_old_sidebars_widgets_data' ) );
 308
 309                 // retrieve_widgets() looks at the global $sidebars_widgets
 310                 $sidebars_widgets = $this->old_sidebars_widgets;
 311                 $sidebars_widgets = retrieve_widgets( 'customize' );
 312                 add_filter( 'option_sidebars_widgets', array( $this, 'filter_option_sidebars_widgets_for_theme_switch' ), 1 );
 313         }
 314
 315         /**
 316          * Filter old_sidebars_widgets_data customizer setting.
 317          *
 318          * When switching themes, filter the Customizer setting
 319          * old_sidebars_widgets_data to supply initial $sidebars_widgets before they
 320          * were overridden by retrieve_widgets(). The value for
 321          * old_sidebars_widgets_data gets set in the old theme's sidebars_widgets
 322          * theme_mod.
 323          *
 324          * @see WP_Customize_Widgets::handle_theme_switch()
 325          * @since 3.9.0
 326          * @access public
 327          *
 328          * @param array $sidebars_widgets
 329          */
 330         public function filter_customize_value_old_sidebars_widgets_data( $old_sidebars_widgets ) {
 331                 return $this->old_sidebars_widgets;
 332         }
 333
 334         /**
 335          * Filter sidebars_widgets option for theme switch.
 336          *
 337          * When switching themes, the retrieve_widgets() function is run when the
 338          * Customizer initializes, and then the new sidebars_widgets here get
 339          * supplied as the default value for the sidebars_widgets option.
 340          *
 341          * @see WP_Customize_Widgets::handle_theme_switch()
 342          * @since 3.9.0
 343          * @access public
 344          *
 345          * @param array $sidebars_widgets
 346          */
 347         public function filter_option_sidebars_widgets_for_theme_switch( $sidebars_widgets ) {
 348                 $sidebars_widgets = $GLOBALS['sidebars_widgets'];
 349                 $sidebars_widgets['array_version'] = 3;
 350                 return $sidebars_widgets;
 351         }
 352
 353         /**
 354          * Make sure all widgets get loaded into the Customizer.
 355          *
 356          * Note: these actions are also fired in wp_ajax_update_widget().
 357          *
 358          * @since 3.9.0
 359          * @access public
 360          */
 361         public function customize_controls_init() {
 362                 /** This action is documented in wp-admin/includes/ajax-actions.php */
 363                 do_action( 'load-widgets.php' );
 364
 365                 /** This action is documented in wp-admin/includes/ajax-actions.php */
 366                 do_action( 'widgets.php' );
 367
 368                 /** This action is documented in wp-admin/widgets.php */
 369                 do_action( 'sidebar_admin_setup' );
 370         }
 371
 372         /**
 373          * Ensure widgets are available for all types of previews.
 374          *
 375          * When in preview, hook to 'customize_register' for settings
 376          * after WordPress is loaded so that all filters have been
 377          * initialized (e.g. Widget Visibility).
 378          *
 379          * @since 3.9.0
 380          * @access public
 381          */
 382         public function schedule_customize_register() {
 383                 if ( is_admin() ) { // @todo for some reason, $wp_customize->is_preview() is true here?
 384                         $this->customize_register();
 385                 } else {
 386                         add_action( 'wp', array( $this, 'customize_register' ) );
 387                 }
 388         }
 389
 390         /**
 391          * Register customizer settings and controls for all sidebars and widgets.
 392          *
 393          * @since 3.9.0
 394          * @access public
 395          */
 396         public function customize_register() {
 397                 global $wp_registered_widgets, $wp_registered_widget_controls, $wp_registered_sidebars;
 398
 399                 $sidebars_widgets = array_merge(
 400                         array( 'wp_inactive_widgets' => array() ),
 401                         array_fill_keys( array_keys( $GLOBALS['wp_registered_sidebars'] ), array() ),
 402                         wp_get_sidebars_widgets()
 403                 );
 404
 405                 $new_setting_ids = array();
 406
 407                 /*
 408                  * Register a setting for all widgets, including those which are active,
 409                  * inactive, and orphaned since a widget may get suppressed from a sidebar
 410                  * via a plugin (like Widget Visibility).
 411                  */
 412                 foreach ( array_keys( $wp_registered_widgets ) as $widget_id ) {
 413                         $setting_id   = $this->get_setting_id( $widget_id );
 414                         $setting_args = $this->get_setting_args( $setting_id );
 415
 416                         $setting_args['sanitize_callback']    = array( $this, 'sanitize_widget_instance' );
 417                         $setting_args['sanitize_js_callback'] = array( $this, 'sanitize_widget_js_instance' );
 418
 419                         $this->manager->add_setting( $setting_id, $setting_args );
 420
 421                         $new_setting_ids[] = $setting_id;
 422                 }
 423
 424                 /*
 425                  * Add a setting which will be supplied for the theme's sidebars_widgets
 426                  * theme_mod when the the theme is switched.
 427                  */
 428                 if ( ! $this->manager->is_theme_active() ) {
 429                         $setting_id = 'old_sidebars_widgets_data';
 430                         $setting_args = $this->get_setting_args( $setting_id, array(
 431                                 'type' => 'global_variable',
 432                         ) );
 433                         $this->manager->add_setting( $setting_id, $setting_args );
 434                 }
 435
 436                 foreach ( $sidebars_widgets as $sidebar_id => $sidebar_widget_ids ) {
 437                         if ( empty( $sidebar_widget_ids ) ) {
 438                                 $sidebar_widget_ids = array();
 439                         }
 440
 441                         $is_registered_sidebar = isset( $GLOBALS['wp_registered_sidebars'][$sidebar_id] );
 442                         $is_inactive_widgets   = ( 'wp_inactive_widgets' === $sidebar_id );
 443                         $is_active_sidebar     = ( $is_registered_sidebar && ! $is_inactive_widgets );
 444
 445                         // Add setting for managing the sidebar's widgets.
 446                         if ( $is_registered_sidebar || $is_inactive_widgets ) {
 447                                 $setting_id   = sprintf( 'sidebars_widgets[%s]', $sidebar_id );
 448                                 $setting_args = $this->get_setting_args( $setting_id );
 449
 450                                 $setting_args['sanitize_callback']    = array( $this, 'sanitize_sidebar_widgets' );
 451                                 $setting_args['sanitize_js_callback'] = array( $this, 'sanitize_sidebar_widgets_js_instance' );
 452
 453                                 $this->manager->add_setting( $setting_id, $setting_args );
 454                                 $new_setting_ids[] = $setting_id;
 455
 456                                 // Add section to contain controls.
 457                                 $section_id = sprintf( 'sidebar-widgets-%s', $sidebar_id );
 458                                 if ( $is_active_sidebar ) {
 459
 460                                         $section_args = array(
 461                                                 /* translators: %s: sidebar name */
 462                                                 'title' => sprintf( __( 'Widgets: %s' ), $GLOBALS['wp_registered_sidebars'][$sidebar_id]['name'] ),
 463                                                 'description' => $GLOBALS['wp_registered_sidebars'][$sidebar_id]['description'],
 464                                                 'priority' => 1000 + array_search( $sidebar_id, array_keys( $wp_registered_sidebars ) ),
 465                                         );
 466
 467                                         /**
 468                                          * Filter Customizer widget section arguments for a given sidebar.
 469                                          *
 470                                          * @since 3.9.0
 471                                          *
 472                                          * @param array      $section_args Array of Customizer widget section arguments.
 473                                          * @param string     $section_id   Customizer section ID.
 474                                          * @param int|string $sidebar_id   Sidebar ID.
 475                                          */
 476                                         $section_args = apply_filters( 'customizer_widgets_section_args', $section_args, $section_id, $sidebar_id );
 477
 478                                         $this->manager->add_section( $section_id, $section_args );
 479
 480                                         $control = new WP_Widget_Area_Customize_Control( $this->manager, $setting_id, array(
 481                                                 'section'    => $section_id,
 482                                                 'sidebar_id' => $sidebar_id,
 483                                                 'priority'   => count( $sidebar_widget_ids ), // place 'Add Widget' and 'Reorder' buttons at end.
 484                                         ) );
 485                                         $new_setting_ids[] = $setting_id;
 486
 487                                         $this->manager->add_control( $control );
 488                                 }
 489                         }
 490
 491                         // Add a control for each active widget (located in a sidebar).
 492                         foreach ( $sidebar_widget_ids as $i => $widget_id ) {
 493
 494                                 // Skip widgets that may have gone away due to a plugin being deactivated.
 495                                 if ( ! $is_active_sidebar || ! isset( $GLOBALS['wp_registered_widgets'][$widget_id] ) ) {
 496                                         continue;
 497                                 }
 498
 499                                 $registered_widget = $GLOBALS['wp_registered_widgets'][$widget_id];
 500                                 $setting_id        = $this->get_setting_id( $widget_id );
 501                                 $id_base           = $GLOBALS['wp_registered_widget_controls'][$widget_id]['id_base'];
 502
 503                                 $control = new WP_Widget_Form_Customize_Control( $this->manager, $setting_id, array(
 504                                         'label'          => $registered_widget['name'],
 505                                         'section'        => $section_id,
 506                                         'sidebar_id'     => $sidebar_id,
 507                                         'widget_id'      => $widget_id,
 508                                         'widget_id_base' => $id_base,
 509                                         'priority'       => $i,
 510                                         'width'          => $wp_registered_widget_controls[$widget_id]['width'],
 511                                         'height'         => $wp_registered_widget_controls[$widget_id]['height'],
 512                                         'is_wide'        => $this->is_wide_widget( $widget_id ),
 513                                 ) );
 514                                 $this->manager->add_control( $control );
 515                         }
 516                 }
 517
 518                 /*
 519                  * We have to register these settings later than customize_preview_init
 520                  * so that other filters have had a chance to run.
 521                  */
 522                 if ( did_action( 'customize_preview_init' ) ) {
 523                         foreach ( $new_setting_ids as $new_setting_id ) {
 524                                 $this->manager->get_setting( $new_setting_id )->preview();
 525                         }
 526                 }
 527                 $this->remove_prepreview_filters();
 528         }
 529
 530         /**
 531          * Covert a widget_id into its corresponding customizer setting ID (option name).
 532          *
 533          * @since 3.9.0
 534          * @access public
 535          *
 536          * @param string $widget_id Widget ID.
 537          * @return string Maybe-parsed widget ID.
 538          */
 539         public function get_setting_id( $widget_id ) {
 540                 $parsed_widget_id = $this->parse_widget_id( $widget_id );
 541                 $setting_id       = sprintf( 'widget_%s', $parsed_widget_id['id_base'] );
 542
 543                 if ( ! is_null( $parsed_widget_id['number'] ) ) {
 544                         $setting_id .= sprintf( '[%d]', $parsed_widget_id['number'] );
 545                 }
 546                 return $setting_id;
 547         }
 548
 549         /**
 550          * Determine whether the widget is considered "wide".
 551          *
 552          * Core widgets which may have controls wider than 250, but can
 553          * still be shown in the narrow customizer panel. The RSS and Text
 554          * widgets in Core, for example, have widths of 400 and yet they
 555          * still render fine in the customizer panel. This method will
 556          * return all Core widgets as being not wide, but this can be
 557          * overridden with the is_wide_widget_in_customizer filter.
 558          *
 559          * @since 3.9.0
 560          * @access public
 561          *
 562          * @param string $widget_id Widget ID.
 563          * @return bool Whether or not the widget is a "wide" widget.
 564          */
 565         public function is_wide_widget( $widget_id ) {
 566                 global $wp_registered_widget_controls;
 567
 568                 $parsed_widget_id = $this->parse_widget_id( $widget_id );
 569                 $width            = $wp_registered_widget_controls[$widget_id]['width'];
 570                 $is_core          = in_array( $parsed_widget_id['id_base'], $this->core_widget_id_bases );
 571                 $is_wide          = ( $width > 250 && ! $is_core );
 572
 573                 /**
 574                  * Filter whether the given widget is considered "wide".
 575                  *
 576                  * @since 3.9.0
 577                  *
 578                  * @param bool   $is_wide   Whether the widget is wide, Default false.
 579                  * @param string $widget_id Widget ID.
 580                  */
 581                 return apply_filters( 'is_wide_widget_in_customizer', $is_wide, $widget_id );
 582         }
 583
 584         /**
 585          * Covert a widget ID into its id_base and number components.
 586          *
 587          * @since 3.9.0
 588          * @access public
 589          *
 590          * @param string $widget_id Widget ID.
 591          * @return array Array containing a widget's id_base and number components.
 592          */
 593         public function parse_widget_id( $widget_id ) {
 594                 $parsed = array(
 595                         'number' => null,
 596                         'id_base' => null,
 597                 );
 598
 599                 if ( preg_match( '/^(.+)-(\d+)$/', $widget_id, $matches ) ) {
 600                         $parsed['id_base'] = $matches[1];
 601                         $parsed['number']  = intval( $matches[2] );
 602                 } else {
 603                         // likely an old single widget
 604                         $parsed['id_base'] = $widget_id;
 605                 }
 606                 return $parsed;
 607         }
 608
 609         /**
 610          * Convert a widget setting ID (option path) to its id_base and number components.
 611          *
 612          * @since 3.9.0
 613          * @access public
 614          *
 615          * @param string $setting_id Widget setting ID.
 616          * @return WP_Error|array Array containing a widget's id_base and number components,
 617          *                        or a WP_Error object.
 618          */
 619         public function parse_widget_setting_id( $setting_id ) {
 620                 if ( ! preg_match( '/^(widget_(.+?))(?:\[(\d+)\])?$/', $setting_id, $matches ) ) {
 621                         return new WP_Error( 'widget_setting_invalid_id' );
 622                 }
 623
 624                 $id_base = $matches[2];
 625                 $number  = isset( $matches[3] ) ? intval( $matches[3] ) : null;
 626
 627                 return compact( 'id_base', 'number' );
 628         }
 629
 630         /**
 631          * Call admin_print_styles-widgets.php and admin_print_styles hooks to
 632          * allow custom styles from plugins.
 633          *
 634          * @since 3.9.0
 635          * @access public
 636          */
 637         public function print_styles() {
 638                 /** This action is documented in wp-admin/admin-header.php */
 639                 do_action( 'admin_print_styles-widgets.php' );
 640
 641                 /** This action is documented in wp-admin/admin-header.php */
 642                 do_action( 'admin_print_styles' );
 643         }
 644
 645         /**
 646          * Call admin_print_scripts-widgets.php and admin_print_scripts hooks to
 647          * allow custom scripts from plugins.
 648          *
 649          * @since 3.9.0
 650          * @access public
 651          */
 652         public function print_scripts() {
 653                 /** This action is documented in wp-admin/admin-header.php */
 654                 do_action( 'admin_print_scripts-widgets.php' );
 655
 656                 /** This action is documented in wp-admin/admin-header.php */
 657                 do_action( 'admin_print_scripts' );
 658         }
 659
 660         /**
 661          * Enqueue scripts and styles for customizer panel and export data to JavaScript.
 662          *
 663          * @since 3.9.0
 664          * @access public
 665          */
 666         public function enqueue_scripts() {
 667                 wp_enqueue_style( 'customize-widgets' );
 668                 wp_enqueue_script( 'customize-widgets' );
 669
 670                 /** This action is documented in wp-admin/admin-header.php */
 671                 do_action( 'admin_enqueue_scripts', 'widgets.php' );
 672
 673                 /*
 674                  * Export available widgets with control_tpl removed from model
 675                  * since plugins need templates to be in the DOM.
 676                  */
 677                 $available_widgets = array();
 678
 679                 foreach ( $this->get_available_widgets() as $available_widget ) {
 680                         unset( $available_widget['control_tpl'] );
 681                         $available_widgets[] = $available_widget;
 682                 }
 683
 684                 $widget_reorder_nav_tpl = sprintf(
 685                         '<div class="widget-reorder-nav"><span class="move-widget" tabindex="0">%1$s</span><span class="move-widget-down" tabindex="0">%2$s</span><span class="move-widget-up" tabindex="0">%3$s</span></div>',
 686                         __( 'Move to another area&hellip;' ),
 687                         __( 'Move down' ),
 688                         __( 'Move up' )
 689                 );
 690
 691                 $move_widget_area_tpl = str_replace(
 692                         array( '{description}', '{btn}' ),
 693                         array(
 694                                 __( 'Select an area to move this widget into:' ),
 695                                 _x( 'Move', 'Move widget' ),
 696                         ),
 697                         '<div class="move-widget-area">
 698                                 <p class="description">{description}</p>
 699                                 <ul class="widget-area-select">
 700                                         <% _.each( sidebars, function ( sidebar ){ %>
 701                                                 <li class="" data-id="<%- sidebar.id %>" title="<%- sidebar.description %>" tabindex="0"><%- sidebar.name %></li>
 702                                         <% }); %>
 703                                 </ul>
 704                                 <div class="move-widget-actions">
 705                                         <button class="move-widget-btn button-secondary" type="button">{btn}</button>
 706                                 </div>
 707                         </div>'
 708                 );
 709
 710                 global $wp_scripts;
 711
 712                 $settings = array(
 713                         'nonce'                => wp_create_nonce( 'update-widget' ),
 714                         'registeredSidebars'   => array_values( $GLOBALS['wp_registered_sidebars'] ),
 715                         'registeredWidgets'    => $GLOBALS['wp_registered_widgets'],
 716                         'availableWidgets'     => $available_widgets, // @todo Merge this with registered_widgets
 717                         'l10n' => array(
 718                                 'saveBtnLabel'     => __( 'Apply' ),
 719                                 'saveBtnTooltip'   => __( 'Save and preview changes before publishing them.' ),
 720                                 'removeBtnLabel'   => __( 'Remove' ),
 721                                 'removeBtnTooltip' => __( 'Trash widget by moving it to the inactive widgets sidebar.' ),
 722                                 'error'            => __( 'An error has occurred. Please reload the page and try again.' ),
 723                         ),
 724                         'tpl' => array(
 725                                 'widgetReorderNav' => $widget_reorder_nav_tpl,
 726                                 'moveWidgetArea'   => $move_widget_area_tpl,
 727                         ),
 728                 );
 729
 730                 foreach ( $settings['registeredWidgets'] as &$registered_widget ) {
 731                         unset( $registered_widget['callback'] ); // may not be JSON-serializeable
 732                 }
 733
 734                 $wp_scripts->add_data(
 735                         'customize-widgets',
 736                         'data',
 737                         sprintf( 'var _wpCustomizeWidgetsSettings = %s;', json_encode( $settings ) )
 738                 );
 739         }
 740
 741         /**
 742          * Render the widget form control templates into the DOM.
 743          *
 744          * @since 3.9.0
 745          * @access public
 746          */
 747         public function output_widget_control_templates() {
 748                 ?>
 749                 <div id="widgets-left"><!-- compatibility with JS which looks for widget templates here -->
 750                 <div id="available-widgets">
 751                         <div id="available-widgets-filter">
 752                                 <label class="screen-reader-text" for="widgets-search"><?php _e( 'Search Widgets' ); ?></label>
 753                                 <input type="search" id="widgets-search" placeholder="<?php esc_attr_e( 'Search widgets&hellip;' ) ?>" />
 754                         </div>
 755                         <?php foreach ( $this->get_available_widgets() as $available_widget ): ?>
 756                                 <div id="widget-tpl-<?php echo esc_attr( $available_widget['id'] ) ?>" data-widget-id="<?php echo esc_attr( $available_widget['id'] ) ?>" class="widget-tpl <?php echo esc_attr( $available_widget['id'] ) ?>" tabindex="0">
 757                                         <?php echo $available_widget['control_tpl']; ?>
 758                                 </div>
 759                         <?php endforeach; ?>
 760                 </div><!-- #available-widgets -->
 761                 </div><!-- #widgets-left -->
 762                 <?php
 763         }
 764
 765         /**
 766          * Call admin_print_footer_scripts and admin_print_scripts hooks to
 767          * allow custom scripts from plugins.
 768          *
 769          * @since 3.9.0
 770          * @access public
 771          */
 772         public function print_footer_scripts() {
 773                 /** This action is documented in wp-admin/admin-footer.php */
 774                 do_action( 'admin_print_footer_scripts' );
 775
 776                 /** This action is documented in wp-admin/admin-footer.php */
 777                 do_action( 'admin_footer-widgets.php' );
 778         }
 779
 780         /**
 781          * Get common arguments to supply when constructing a Customizer setting.
 782          *
 783          * @since 3.9.0
 784          * @access public
 785          *
 786          * @param string $id        Widget setting ID.
 787          * @param array  $overrides Array of setting overrides.
 788          * @return array Possibly modified setting arguments.
 789          */
 790         public function get_setting_args( $id, $overrides = array() ) {
 791                 $args = array(
 792                         'type'       => 'option',
 793                         'capability' => 'edit_theme_options',
 794                         'transport'  => 'refresh',
 795                         'default'    => array(),
 796                 );
 797                 $args = array_merge( $args, $overrides );
 798
 799                 /**
 800                  * Filter the common arguments supplied when constructing a Customizer setting.
 801                  *
 802                  * @since 3.9.0
 803                  *
 804                  * @see WP_Customize_Setting
 805                  *
 806                  * @param array  $args Array of Customizer setting arguments.
 807                  * @param string $id   Widget setting ID.
 808                  */
 809                 return apply_filters( 'widget_customizer_setting_args', $args, $id );
 810         }
 811
 812         /**
 813          * Make sure that sidebar widget arrays only ever contain widget IDS.
 814          *
 815          * Used as the 'sanitize_callback' for each $sidebars_widgets setting.
 816          *
 817          * @since 3.9.0
 818          * @access public
 819          *
 820          * @param array $widget_ids Array of widget IDs.
 821          * @return array Array of sanitized widget IDs.
 822          */
 823         public function sanitize_sidebar_widgets( $widget_ids ) {
 824                 global $wp_registered_widgets;
 825
 826                 $widget_ids           = array_map( 'strval', (array) $widget_ids );
 827                 $sanitized_widget_ids = array();
 828
 829                 foreach ( $widget_ids as $widget_id ) {
 830                         if ( array_key_exists( $widget_id, $wp_registered_widgets ) ) {
 831                                 $sanitized_widget_ids[] = $widget_id;
 832                         }
 833                 }
 834                 return $sanitized_widget_ids;
 835         }
 836
 837         /**
 838          * Build up an index of all available widgets for use in Backbone models.
 839          *
 840          * @since 3.9.0
 841          * @access public
 842          *
 843          * @see wp_list_widgets()
 844          *
 845          * @return array List of available widgets.
 846          */
 847         public function get_available_widgets() {
 848                 static $available_widgets = array();
 849                 if ( ! empty( $available_widgets ) ) {
 850                         return $available_widgets;
 851                 }
 852
 853                 global $wp_registered_widgets, $wp_registered_widget_controls;
 854                 require_once ABSPATH . '/wp-admin/includes/widgets.php'; // for next_widget_id_number()
 855
 856                 $sort = $wp_registered_widgets;
 857                 usort( $sort, array( $this, '_sort_name_callback' ) );
 858                 $done = array();
 859
 860                 foreach ( $sort as $widget ) {
 861                         if ( in_array( $widget['callback'], $done, true ) ) { // We already showed this multi-widget
 862                                 continue;
 863                         }
 864
 865                         $sidebar = is_active_widget( $widget['callback'], $widget['id'], false, false );
 866                         $done[]  = $widget['callback'];
 867
 868                         if ( ! isset( $widget['params'][0] ) ) {
 869                                 $widget['params'][0] = array();
 870                         }
 871
 872                         $available_widget = $widget;
 873                         unset( $available_widget['callback'] ); // not serializable to JSON
 874
 875                         $args = array(
 876                                 'widget_id'   => $widget['id'],
 877                                 'widget_name' => $widget['name'],
 878                                 '_display'    => 'template',
 879                         );
 880
 881                         $is_disabled     = false;
 882                         $is_multi_widget = ( isset( $wp_registered_widget_controls[$widget['id']]['id_base'] ) && isset( $widget['params'][0]['number'] ) );
 883                         if ( $is_multi_widget ) {
 884                                 $id_base            = $wp_registered_widget_controls[$widget['id']]['id_base'];
 885                                 $args['_temp_id']   = "$id_base-__i__";
 886                                 $args['_multi_num'] = next_widget_id_number( $id_base );
 887                                 $args['_add']       = 'multi';
 888                         } else {
 889                                 $args['_add'] = 'single';
 890
 891                                 if ( $sidebar && 'wp_inactive_widgets' !== $sidebar ) {
 892                                         $is_disabled = true;
 893                                 }
 894                                 $id_base = $widget['id'];
 895                         }
 896
 897                         $list_widget_controls_args = wp_list_widget_controls_dynamic_sidebar( array( 0 => $args, 1 => $widget['params'][0] ) );
 898                         $control_tpl = $this->get_widget_control( $list_widget_controls_args );
 899
 900                         // The properties here are mapped to the Backbone Widget model.
 901                         $available_widget = array_merge( $available_widget, array(
 902                                 'temp_id'      => isset( $args['_temp_id'] ) ? $args['_temp_id'] : null,
 903                                 'is_multi'     => $is_multi_widget,
 904                                 'control_tpl'  => $control_tpl,
 905                                 'multi_number' => ( $args['_add'] === 'multi' ) ? $args['_multi_num'] : false,
 906                                 'is_disabled'  => $is_disabled,
 907                                 'id_base'      => $id_base,
 908                                 'transport'    => 'refresh',
 909                                 'width'        => $wp_registered_widget_controls[$widget['id']]['width'],
 910                                 'height'       => $wp_registered_widget_controls[$widget['id']]['height'],
 911                                 'is_wide'      => $this->is_wide_widget( $widget['id'] ),
 912                         ) );
 913
 914                         $available_widgets[] = $available_widget;
 915                 }
 916
 917                 return $available_widgets;
 918         }
 919
 920         /**
 921          * Naturally order available widgets by name.
 922          *
 923          * @since 3.9.0
 924          * @static
 925          * @access protected
 926          *
 927          * @param array $widget_a The first widget to compare.
 928          * @param array $widget_b The second widget to compare.
 929          * @return int Reorder position for the current widget comparison.
 930          */
 931         protected function _sort_name_callback( $widget_a, $widget_b ) {
 932                 return strnatcasecmp( $widget_a['name'], $widget_b['name'] );
 933         }
 934
 935         /**
 936          * Get the widget control markup.
 937          *
 938          * @since 3.9.0
 939          * @access public
 940          *
 941          * @param array $args Widget control arguments.
 942          * @return string Widget control form HTML markup.
 943          */
 944         public function get_widget_control( $args ) {
 945                 ob_start();
 946
 947                 call_user_func_array( 'wp_widget_control', $args );
 948                 $replacements = array(
 949                         '<form action="" method="post">' => '<div class="form">',
 950                         '</form>' => '</div><!-- .form -->',
 951                 );
 952
 953                 $control_tpl = ob_get_clean();
 954
 955                 $control_tpl = str_replace( array_keys( $replacements ), array_values( $replacements ), $control_tpl );
 956
 957                 return $control_tpl;
 958         }
 959
 960         /**
 961          * Add hooks for the customizer preview.
 962          *
 963          * @since 3.9.0
 964          * @access public
 965          */
 966         public function customize_preview_init() {
 967                 add_filter( 'sidebars_widgets',   array( $this, 'preview_sidebars_widgets' ), 1 );
 968                 add_action( 'wp_enqueue_scripts', array( $this, 'customize_preview_enqueue' ) );
 969                 add_action( 'wp_print_styles',    array( $this, 'print_preview_css' ), 1 );
 970                 add_action( 'wp_footer',          array( $this, 'export_preview_data' ), 20 );
 971         }
 972
 973         /**
 974          * When previewing, make sure the proper previewing widgets are used.
 975          *
 976          * Because wp_get_sidebars_widgets() gets called early at init
 977          * (via wp_convert_widget_settings()) and can set global variable
 978          * $_wp_sidebars_widgets to the value of get_option( 'sidebars_widgets' )
 979          * before the customizer preview filter is added, we have to reset
 980          * it after the filter has been added.
 981          *
 982          * @since 3.9.0
 983          * @access public
 984          *
 985          * @param array $sidebars_widgets List of widgets for the current sidebar.
 986          */
 987         public function preview_sidebars_widgets( $sidebars_widgets ) {
 988                 $sidebars_widgets = get_option( 'sidebars_widgets' );
 989
 990                 unset( $sidebars_widgets['array_version'] );
 991                 return $sidebars_widgets;
 992         }
 993
 994         /**
 995          * Enqueue scripts for the Customizer preview.
 996          *
 997          * @since 3.9.0
 998          * @access public
 999          */
1000         public function customize_preview_enqueue() {
1001                 wp_enqueue_script( 'customize-preview-widgets' );
1002         }
1003
1004         /**
1005          * Insert default style for highlighted widget at early point so theme
1006          * stylesheet can override.
1007          *
1008          * @since 3.9.0
1009          * @access public
1010          *
1011          * @action wp_print_styles
1012          */
1013         public function print_preview_css() {
1014                 ?>
1015                 <style>
1016                 .widget-customizer-highlighted-widget {
1017                         outline: none;
1018                         -webkit-box-shadow: 0 0 2px rgba(30,140,190,0.8);
1019                         box-shadow: 0 0 2px rgba(30,140,190,0.8);
1020                         position: relative;
1021                         z-index: 1;
1022                 }
1023                 </style>
1024                 <?php
1025         }
1026
1027         /**
1028          * At the very end of the page, at the very end of the wp_footer,
1029          * communicate the sidebars that appeared on the page.
1030          *
1031          * @since 3.9.0
1032          * @access public
1033          */
1034         public function export_preview_data() {
1035
1036                 // Prepare customizer settings to pass to Javascript.
1037                 $settings = array(
1038                         'renderedSidebars'   => array_fill_keys( array_unique( $this->rendered_sidebars ), true ),
1039                         'renderedWidgets'    => array_fill_keys( array_keys( $this->rendered_widgets ), true ),
1040                         'registeredSidebars' => array_values( $GLOBALS['wp_registered_sidebars'] ),
1041                         'registeredWidgets'  => $GLOBALS['wp_registered_widgets'],
1042                         'l10n'               => array(
1043                                 'widgetTooltip' => __( 'Shift-click to edit this widget.' ),
1044                         ),
1045                 );
1046                 foreach ( $settings['registeredWidgets'] as &$registered_widget ) {
1047                         unset( $registered_widget['callback'] ); // may not be JSON-serializeable
1048                 }
1049
1050                 ?>
1051                 <script type="text/javascript">
1052                         var _wpWidgetCustomizerPreviewSettings = <?php echo json_encode( $settings ); ?>;
1053                 </script>
1054                 <?php
1055         }
1056
1057         /**
1058          * Keep track of the widgets that were rendered.
1059          *
1060          * @since 3.9.0
1061          * @access public
1062          *
1063          * @param array $widget Rendered widget to tally.
1064          */
1065         public function tally_rendered_widgets( $widget ) {
1066                 $this->rendered_widgets[$widget['id']] = true;
1067         }
1068
1069         /**
1070          * Tally the sidebars rendered via is_active_sidebar().
1071          *
1072          * Keep track of the times that is_active_sidebar() is called
1073          * in the template, and assume that this means that the sidebar
1074          * would be rendered on the template if there were widgets
1075          * populating it.
1076          *
1077          * @since 3.9.0
1078          * @access public
1079          *
1080          * @param bool    $is_active  Whether the sidebar is active.
1081          * @pasram string $sidebar_id Sidebar ID.
1082          */
1083         public function tally_sidebars_via_is_active_sidebar_calls( $is_active, $sidebar_id ) {
1084                 if ( isset( $GLOBALS['wp_registered_sidebars'][$sidebar_id] ) ) {
1085                         $this->rendered_sidebars[] = $sidebar_id;
1086                 }
1087                 /*
1088                  * We may need to force this to true, and also force-true the value
1089                  * for 'dynamic_sidebar_has_widgets' if we want to ensure that there
1090                  * is an area to drop widgets into, if the sidebar is empty.
1091                  */
1092                 return $is_active;
1093         }
1094
1095         /**
1096          * Tally the sidebars rendered via dynamic_sidebar().
1097          *
1098          * Keep track of the times that dynamic_sidebar() is called in the template,
1099          * and assume this means the sidebar would be rendered on the template if
1100          * there were widgets populating it.
1101          *
1102          * @since 3.9.0
1103          * @access public
1104          *
1105          * @param bool   $has_widgets Whether the current sidebar has widgets.
1106          * @param string $sidebar_id  Sidebar ID.
1107          */
1108         public function tally_sidebars_via_dynamic_sidebar_calls( $has_widgets, $sidebar_id ) {
1109                 if ( isset( $GLOBALS['wp_registered_sidebars'][$sidebar_id] ) ) {
1110                         $this->rendered_sidebars[] = $sidebar_id;
1111                 }
1112
1113                 /*
1114                  * We may need to force this to true, and also force-true the value
1115                  * for 'is_active_sidebar' if we want to ensure there is an area to
1116                  * drop widgets into, if the sidebar is empty.
1117                  */
1118                 return $has_widgets;
1119         }
1120
1121         /**
1122          * Get a widget instance's hash key.
1123          *
1124          * Serialize an instance and hash it with the AUTH_KEY; when a JS value is
1125          * posted back to save, this instance hash key is used to ensure that the
1126          * serialized_instance was not tampered with, but that it had originated
1127          * from WordPress and so is sanitized.
1128          *
1129          * @since 3.9.0
1130          * @access protected
1131          *
1132          * @param array $instance Widget instance.
1133          * @return string Widget instance's hash key.
1134          */
1135         protected function get_instance_hash_key( $instance ) {
1136                 $hash = md5( AUTH_KEY . serialize( $instance ) );
1137                 return $hash;
1138         }
1139
1140         /**
1141          * Sanitize a widget instance.
1142          *
1143          * Unserialize the JS-instance for storing in the options. It's important
1144          * that this filter only get applied to an instance once.
1145          *
1146          * @since 3.9.0
1147          * @access public
1148          *
1149          * @param array $value Widget instance to sanitize.
1150          * @return array Sanitized widget instance.
1151          */
1152         public function sanitize_widget_instance( $value ) {
1153                 if ( $value === array() ) {
1154                         return $value;
1155                 }
1156
1157                 if ( empty( $value['is_widget_customizer_js_value'] )
1158                         || empty( $value['instance_hash_key'] )
1159                         || empty( $value['encoded_serialized_instance'] ) )
1160                 {
1161                         return null;
1162                 }
1163
1164                 $decoded = base64_decode( $value['encoded_serialized_instance'], true );
1165
1166                 if ( false === $decoded ) {
1167                         return null;
1168                 }
1169                 $instance = unserialize( $decoded );
1170
1171                 if ( false === $instance ) {
1172                         return null;
1173                 }
1174                 if ( $this->get_instance_hash_key( $instance ) !== $value['instance_hash_key'] ) {
1175                         return null;
1176                 }
1177                 return $instance;
1178         }
1179
1180         /**
1181          * Convert widget instance into JSON-representable format.
1182          *
1183          * @since 3.9.0
1184          * @access public
1185          *
1186          * @param array $value Widget instance to convert to JSON.
1187          * @return array JSON-converted widget instance.
1188          */
1189         public function sanitize_widget_js_instance( $value ) {
1190                 if ( empty( $value['is_widget_customizer_js_value'] ) ) {
1191                         $serialized = serialize( $value );
1192
1193                         $value = array(
1194                                 'encoded_serialized_instance'   => base64_encode( $serialized ),
1195                                 'title'                         => empty( $value['title'] ) ? '' : $value['title'],
1196                                 'is_widget_customizer_js_value' => true,
1197                                 'instance_hash_key'             => $this->get_instance_hash_key( $value ),
1198                         );
1199                 }
1200                 return $value;
1201         }
1202
1203         /**
1204          * Strip out widget IDs for widgets which are no longer registered.
1205          *
1206          * One example where this might happen is when a plugin orphans a widget
1207          * in a sidebar upon deactivation.
1208          *
1209          * @since 3.9.0
1210          * @access public
1211          *
1212          * @param array $widget_ids List of widget IDs.
1213          * @return array Parsed list of widget IDs.
1214          */
1215         public function sanitize_sidebar_widgets_js_instance( $widget_ids ) {
1216                 global $wp_registered_widgets;
1217                 $widget_ids = array_values( array_intersect( $widget_ids, array_keys( $wp_registered_widgets ) ) );
1218                 return $widget_ids;
1219         }
1220
1221         /**
1222          * Find and invoke the widget update and control callbacks.
1223          *
1224          * Requires that $_POST be populated with the instance data.
1225          *
1226          * @since 3.9.0
1227          * @access public
1228          *
1229          * @param  string $widget_id Widget ID.
1230          * @return WP_Error|array Array containing the updated widget information.
1231          *                        A WP_Error object, otherwise.
1232          */
1233         public function call_widget_update( $widget_id ) {
1234                 global $wp_registered_widget_updates, $wp_registered_widget_controls;
1235
1236                 $this->start_capturing_option_updates();
1237                 $parsed_id   = $this->parse_widget_id( $widget_id );
1238                 $option_name = 'widget_' . $parsed_id['id_base'];
1239
1240                 /*
1241                  * If a previously-sanitized instance is provided, populate the input vars
1242                  * with its values so that the widget update callback will read this instance
1243                  */
1244                 $added_input_vars = array();
1245                 if ( ! empty( $_POST['sanitized_widget_setting'] ) ) {
1246                         $sanitized_widget_setting = json_decode( $this->get_post_value( 'sanitized_widget_setting' ), true );
1247                         if ( false === $sanitized_widget_setting ) {
1248                                 $this->stop_capturing_option_updates();
1249                                 return new WP_Error( 'widget_setting_malformed' );
1250                         }
1251
1252                         $instance = $this->sanitize_widget_instance( $sanitized_widget_setting );
1253                         if ( is_null( $instance ) ) {
1254                                 $this->stop_capturing_option_updates();
1255                                 return new WP_Error( 'widget_setting_unsanitized' );
1256                         }
1257
1258                         if ( ! is_null( $parsed_id['number'] ) ) {
1259                                 $value = array();
1260                                 $value[$parsed_id['number']] = $instance;
1261                                 $key = 'widget-' . $parsed_id['id_base'];
1262                                 $_REQUEST[$key] = $_POST[$key] = wp_slash( $value );
1263                                 $added_input_vars[] = $key;
1264                         } else {
1265                                 foreach ( $instance as $key => $value ) {
1266                                         $_REQUEST[$key] = $_POST[$key] = wp_slash( $value );
1267                                         $added_input_vars[] = $key;
1268                                 }
1269                         }
1270                 }
1271
1272                 // Invoke the widget update callback.
1273                 foreach ( (array) $wp_registered_widget_updates as $name => $control ) {
1274                         if ( $name === $parsed_id['id_base'] && is_callable( $control['callback'] ) ) {
1275                                 ob_start();
1276                                 call_user_func_array( $control['callback'], $control['params'] );
1277                                 ob_end_clean();
1278                                 break;
1279                         }
1280                 }
1281
1282                 // Clean up any input vars that were manually added
1283                 foreach ( $added_input_vars as $key ) {
1284                         unset( $_POST[$key] );
1285                         unset( $_REQUEST[$key] );
1286                 }
1287
1288                 // Make sure the expected option was updated.
1289                 if ( 0 !== $this->count_captured_options() ) {
1290                         if ( $this->count_captured_options() > 1 ) {
1291                                 $this->stop_capturing_option_updates();
1292                                 return new WP_Error( 'widget_setting_too_many_options' );
1293                         }
1294
1295                         $updated_option_name = key( $this->get_captured_options() );
1296                         if ( $updated_option_name !== $option_name ) {
1297                                 $this->stop_capturing_option_updates();
1298                                 return new WP_Error( 'widget_setting_unexpected_option' );
1299                         }
1300                 }
1301
1302                 // Obtain the widget control with the updated instance in place.
1303                 ob_start();
1304
1305                 $form = $wp_registered_widget_controls[$widget_id];
1306                 if ( $form ) {
1307                         call_user_func_array( $form['callback'], $form['params'] );
1308                 }
1309
1310                 $form = ob_get_clean();
1311
1312                 // Obtain the widget instance.
1313                 $option = get_option( $option_name );
1314
1315                 if ( null !== $parsed_id['number'] ) {
1316                         $instance = $option[$parsed_id['number']];
1317                 } else {
1318                         $instance = $option;
1319                 }
1320
1321                 $this->stop_capturing_option_updates();
1322
1323                 return compact( 'instance', 'form' );
1324         }
1325
1326         /**
1327          * Update widget settings asynchronously.
1328          *
1329          * Allows the Customizer to update a widget using its form, but return the new
1330          * instance info via Ajax instead of saving it to the options table.
1331          *
1332          * Most code here copied from wp_ajax_save_widget()
1333          *
1334          * @since 3.9.0
1335          * @access public
1336          *
1337          * @see wp_ajax_save_widget()
1338          *
1339          */
1340         public function wp_ajax_update_widget() {
1341
1342                 if ( ! is_user_logged_in() ) {
1343                         wp_die( 0 );
1344                 }
1345
1346                 check_ajax_referer( 'update-widget', 'nonce' );
1347
1348                 if ( ! current_user_can( 'edit_theme_options' ) ) {
1349                         wp_die( -1 );
1350                 }
1351
1352                 if ( ! isset( $_POST['widget-id'] ) ) {
1353                         wp_send_json_error();
1354                 }
1355
1356                 /** This action is documented in wp-admin/includes/ajax-actions.php */
1357                 do_action( 'load-widgets.php' );
1358
1359                 /** This action is documented in wp-admin/includes/ajax-actions.php */
1360                 do_action( 'widgets.php' );
1361
1362                 /** This action is documented in wp-admin/widgets.php */
1363                 do_action( 'sidebar_admin_setup' );
1364
1365                 $widget_id = $this->get_post_value( 'widget-id' );
1366                 $parsed_id = $this->parse_widget_id( $widget_id );
1367                 $id_base   = $parsed_id['id_base'];
1368
1369                 if ( isset( $_POST['widget-' . $id_base] ) && is_array( $_POST['widget-' . $id_base] ) && preg_match( '/__i__|%i%/', key( $_POST['widget-' . $id_base] ) ) ) {
1370                         wp_send_json_error();
1371                 }
1372
1373                 $updated_widget = $this->call_widget_update( $widget_id ); // => {instance,form}
1374                 if ( is_wp_error( $updated_widget ) ) {
1375                         wp_send_json_error();
1376                 }
1377
1378                 $form = $updated_widget['form'];
1379                 $instance = $this->sanitize_widget_js_instance( $updated_widget['instance'] );
1380
1381                 wp_send_json_success( compact( 'form', 'instance' ) );
1382         }
1383
1384         /***************************************************************************
1385          * Option Update Capturing
1386          ***************************************************************************/
1387
1388         /**
1389          * List of captured widget option updates.
1390          *
1391          * @since 3.9.0
1392          * @access protected
1393          * @var array $_captured_options Values updated while option capture is happening.
1394          */
1395         protected $_captured_options = array();
1396
1397         /**
1398          * Whether option capture is currently happening.
1399          *
1400          * @since 3.9.0
1401          * @access protected
1402          * @var bool $_is_current Whether option capture is currently happening or not.
1403          */
1404         protected $_is_capturing_option_updates = false;
1405
1406         /**
1407          * Determine whether the captured option update should be ignored.
1408          *
1409          * @since 3.9.0
1410          * @access protected
1411          *
1412          * @param string $option_name Option name.
1413          * @return boolean Whether the option capture is ignored.
1414          */
1415         protected function is_option_capture_ignored( $option_name ) {
1416                 return ( 0 === strpos( $option_name, '_transient_' ) );
1417         }
1418
1419         /**
1420          * Retrieve captured widget option updates.
1421          *
1422          * @since 3.9.0
1423          * @access protected
1424          *
1425          * @return array Array of captured options.
1426          */
1427         protected function get_captured_options() {
1428                 return $this->_captured_options;
1429         }
1430
1431         /**
1432          * Get the number of captured widget option updates.
1433          *
1434          * @since 3.9.0
1435          * @access protected
1436          *
1437          * @return int Number of updated options.
1438          */
1439         protected function count_captured_options() {
1440                 return count( $this->_captured_options );
1441         }
1442
1443         /**
1444          * Start keeping track of changes to widget options, caching new values.
1445          *
1446          * @since 3.9.0
1447          * @access protected
1448          */
1449         protected function start_capturing_option_updates() {
1450                 if ( $this->_is_capturing_option_updates ) {
1451                         return;
1452                 }
1453
1454                 $this->_is_capturing_option_updates = true;
1455
1456                 add_filter( 'pre_update_option', array( $this, 'capture_filter_pre_update_option' ), 10, 3 );
1457         }
1458
1459         /**
1460          * Pre-filter captured option values before updating.
1461          *
1462          * @since 3.9.0
1463          * @access public
1464          *
1465          * @param mixed $new_value
1466          * @param string $option_name
1467          * @param mixed $old_value
1468          * @return mixed
1469          */
1470         public function capture_filter_pre_update_option( $new_value, $option_name, $old_value ) {
1471                 if ( $this->is_option_capture_ignored( $option_name ) ) {
1472                         return;
1473                 }
1474
1475                 if ( ! isset( $this->_captured_options[$option_name] ) ) {
1476                         add_filter( "pre_option_{$option_name}", array( $this, 'capture_filter_pre_get_option' ) );
1477                 }
1478
1479                 $this->_captured_options[$option_name] = $new_value;
1480
1481                 return $old_value;
1482         }
1483
1484         /**
1485          * Pre-filter captured option values before retrieving.
1486          *
1487          * @since 3.9.0
1488          * @access public
1489          *
1490          * @param mixed $value Option
1491          * @return mixed
1492          */
1493         public function capture_filter_pre_get_option( $value ) {
1494                 $option_name = preg_replace( '/^pre_option_/', '', current_filter() );
1495
1496                 if ( isset( $this->_captured_options[$option_name] ) ) {
1497                         $value = $this->_captured_options[$option_name];
1498
1499                         /** This filter is documented in wp-includes/option.php */
1500                         $value = apply_filters( 'option_' . $option_name, $value );
1501                 }
1502
1503                 return $value;
1504         }
1505
1506         /**
1507          * Undo any changes to the options since options capture began.
1508          *
1509          * @since 3.9.0
1510          * @access protected
1511          */
1512         protected function stop_capturing_option_updates() {
1513                 if ( ! $this->_is_capturing_option_updates ) {
1514                         return;
1515                 }
1516
1517                 remove_filter( 'pre_update_option', array( $this, 'capture_filter_pre_update_option' ), 10, 3 );
1518
1519                 foreach ( array_keys( $this->_captured_options ) as $option_name ) {
1520                         remove_filter( "pre_option_{$option_name}", array( $this, 'capture_filter_pre_get_option' ) );
1521                 }
1522
1523                 $this->_captured_options = array();
1524                 $this->_is_capturing_option_updates = false;
1525         }
1526 }