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                 $this->manager->add_panel( 'widgets', array(
 437                         'title'       => __( 'Widgets' ),
 438                         'description' => __( 'Widgets are independent sections of content that can be placed into widgetized areas provided by your theme (commonly called sidebars).' ),
 439                         'priority'    => 110,
 440                 ) );
 441
 442                 foreach ( $sidebars_widgets as $sidebar_id => $sidebar_widget_ids ) {
 443                         if ( empty( $sidebar_widget_ids ) ) {
 444                                 $sidebar_widget_ids = array();
 445                         }
 446
 447                         $is_registered_sidebar = isset( $GLOBALS['wp_registered_sidebars'][$sidebar_id] );
 448                         $is_inactive_widgets   = ( 'wp_inactive_widgets' === $sidebar_id );
 449                         $is_active_sidebar     = ( $is_registered_sidebar && ! $is_inactive_widgets );
 450
 451                         // Add setting for managing the sidebar's widgets.
 452                         if ( $is_registered_sidebar || $is_inactive_widgets ) {
 453                                 $setting_id   = sprintf( 'sidebars_widgets[%s]', $sidebar_id );
 454                                 $setting_args = $this->get_setting_args( $setting_id );
 455
 456                                 $setting_args['sanitize_callback']    = array( $this, 'sanitize_sidebar_widgets' );
 457                                 $setting_args['sanitize_js_callback'] = array( $this, 'sanitize_sidebar_widgets_js_instance' );
 458
 459                                 $this->manager->add_setting( $setting_id, $setting_args );
 460                                 $new_setting_ids[] = $setting_id;
 461
 462                                 // Add section to contain controls.
 463                                 $section_id = sprintf( 'sidebar-widgets-%s', $sidebar_id );
 464                                 if ( $is_active_sidebar ) {
 465
 466                                         $section_args = array(
 467                                                 'title' => $GLOBALS['wp_registered_sidebars'][ $sidebar_id ]['name'],
 468                                                 'description' => $GLOBALS['wp_registered_sidebars'][ $sidebar_id ]['description'],
 469                                                 'priority' => array_search( $sidebar_id, array_keys( $wp_registered_sidebars ) ),
 470                                                 'panel' => 'widgets',
 471                                         );
 472
 473                                         /**
 474                                          * Filter Customizer widget section arguments for a given sidebar.
 475                                          *
 476                                          * @since 3.9.0
 477                                          *
 478                                          * @param array      $section_args Array of Customizer widget section arguments.
 479                                          * @param string     $section_id   Customizer section ID.
 480                                          * @param int|string $sidebar_id   Sidebar ID.
 481                                          */
 482                                         $section_args = apply_filters( 'customizer_widgets_section_args', $section_args, $section_id, $sidebar_id );
 483
 484                                         $this->manager->add_section( $section_id, $section_args );
 485
 486                                         $control = new WP_Widget_Area_Customize_Control( $this->manager, $setting_id, array(
 487                                                 'section'    => $section_id,
 488                                                 'sidebar_id' => $sidebar_id,
 489                                                 'priority'   => count( $sidebar_widget_ids ), // place 'Add Widget' and 'Reorder' buttons at end.
 490                                         ) );
 491                                         $new_setting_ids[] = $setting_id;
 492
 493                                         $this->manager->add_control( $control );
 494                                 }
 495                         }
 496
 497                         // Add a control for each active widget (located in a sidebar).
 498                         foreach ( $sidebar_widget_ids as $i => $widget_id ) {
 499
 500                                 // Skip widgets that may have gone away due to a plugin being deactivated.
 501                                 if ( ! $is_active_sidebar || ! isset( $GLOBALS['wp_registered_widgets'][$widget_id] ) ) {
 502                                         continue;
 503                                 }
 504
 505                                 $registered_widget = $GLOBALS['wp_registered_widgets'][$widget_id];
 506                                 $setting_id        = $this->get_setting_id( $widget_id );
 507                                 $id_base           = $GLOBALS['wp_registered_widget_controls'][$widget_id]['id_base'];
 508
 509                                 $control = new WP_Widget_Form_Customize_Control( $this->manager, $setting_id, array(
 510                                         'label'          => $registered_widget['name'],
 511                                         'section'        => $section_id,
 512                                         'sidebar_id'     => $sidebar_id,
 513                                         'widget_id'      => $widget_id,
 514                                         'widget_id_base' => $id_base,
 515                                         'priority'       => $i,
 516                                         'width'          => $wp_registered_widget_controls[$widget_id]['width'],
 517                                         'height'         => $wp_registered_widget_controls[$widget_id]['height'],
 518                                         'is_wide'        => $this->is_wide_widget( $widget_id ),
 519                                 ) );
 520                                 $this->manager->add_control( $control );
 521                         }
 522                 }
 523
 524                 /*
 525                  * We have to register these settings later than customize_preview_init
 526                  * so that other filters have had a chance to run.
 527                  */
 528                 if ( did_action( 'customize_preview_init' ) ) {
 529                         foreach ( $new_setting_ids as $new_setting_id ) {
 530                                 $this->manager->get_setting( $new_setting_id )->preview();
 531                         }
 532                 }
 533                 $this->remove_prepreview_filters();
 534         }
 535
 536         /**
 537          * Covert a widget_id into its corresponding customizer setting ID (option name).
 538          *
 539          * @since 3.9.0
 540          * @access public
 541          *
 542          * @param string $widget_id Widget ID.
 543          * @return string Maybe-parsed widget ID.
 544          */
 545         public function get_setting_id( $widget_id ) {
 546                 $parsed_widget_id = $this->parse_widget_id( $widget_id );
 547                 $setting_id       = sprintf( 'widget_%s', $parsed_widget_id['id_base'] );
 548
 549                 if ( ! is_null( $parsed_widget_id['number'] ) ) {
 550                         $setting_id .= sprintf( '[%d]', $parsed_widget_id['number'] );
 551                 }
 552                 return $setting_id;
 553         }
 554
 555         /**
 556          * Determine whether the widget is considered "wide".
 557          *
 558          * Core widgets which may have controls wider than 250, but can
 559          * still be shown in the narrow customizer panel. The RSS and Text
 560          * widgets in Core, for example, have widths of 400 and yet they
 561          * still render fine in the customizer panel. This method will
 562          * return all Core widgets as being not wide, but this can be
 563          * overridden with the is_wide_widget_in_customizer filter.
 564          *
 565          * @since 3.9.0
 566          * @access public
 567          *
 568          * @param string $widget_id Widget ID.
 569          * @return bool Whether or not the widget is a "wide" widget.
 570          */
 571         public function is_wide_widget( $widget_id ) {
 572                 global $wp_registered_widget_controls;
 573
 574                 $parsed_widget_id = $this->parse_widget_id( $widget_id );
 575                 $width            = $wp_registered_widget_controls[$widget_id]['width'];
 576                 $is_core          = in_array( $parsed_widget_id['id_base'], $this->core_widget_id_bases );
 577                 $is_wide          = ( $width > 250 && ! $is_core );
 578
 579                 /**
 580                  * Filter whether the given widget is considered "wide".
 581                  *
 582                  * @since 3.9.0
 583                  *
 584                  * @param bool   $is_wide   Whether the widget is wide, Default false.
 585                  * @param string $widget_id Widget ID.
 586                  */
 587                 return apply_filters( 'is_wide_widget_in_customizer', $is_wide, $widget_id );
 588         }
 589
 590         /**
 591          * Covert a widget ID into its id_base and number components.
 592          *
 593          * @since 3.9.0
 594          * @access public
 595          *
 596          * @param string $widget_id Widget ID.
 597          * @return array Array containing a widget's id_base and number components.
 598          */
 599         public function parse_widget_id( $widget_id ) {
 600                 $parsed = array(
 601                         'number' => null,
 602                         'id_base' => null,
 603                 );
 604
 605                 if ( preg_match( '/^(.+)-(\d+)$/', $widget_id, $matches ) ) {
 606                         $parsed['id_base'] = $matches[1];
 607                         $parsed['number']  = intval( $matches[2] );
 608                 } else {
 609                         // likely an old single widget
 610                         $parsed['id_base'] = $widget_id;
 611                 }
 612                 return $parsed;
 613         }
 614
 615         /**
 616          * Convert a widget setting ID (option path) to its id_base and number components.
 617          *
 618          * @since 3.9.0
 619          * @access public
 620          *
 621          * @param string $setting_id Widget setting ID.
 622          * @return WP_Error|array Array containing a widget's id_base and number components,
 623          *                        or a WP_Error object.
 624          */
 625         public function parse_widget_setting_id( $setting_id ) {
 626                 if ( ! preg_match( '/^(widget_(.+?))(?:\[(\d+)\])?$/', $setting_id, $matches ) ) {
 627                         return new WP_Error( 'widget_setting_invalid_id' );
 628                 }
 629
 630                 $id_base = $matches[2];
 631                 $number  = isset( $matches[3] ) ? intval( $matches[3] ) : null;
 632
 633                 return compact( 'id_base', 'number' );
 634         }
 635
 636         /**
 637          * Call admin_print_styles-widgets.php and admin_print_styles hooks to
 638          * allow custom styles from plugins.
 639          *
 640          * @since 3.9.0
 641          * @access public
 642          */
 643         public function print_styles() {
 644                 /** This action is documented in wp-admin/admin-header.php */
 645                 do_action( 'admin_print_styles-widgets.php' );
 646
 647                 /** This action is documented in wp-admin/admin-header.php */
 648                 do_action( 'admin_print_styles' );
 649         }
 650
 651         /**
 652          * Call admin_print_scripts-widgets.php and admin_print_scripts hooks to
 653          * allow custom scripts from plugins.
 654          *
 655          * @since 3.9.0
 656          * @access public
 657          */
 658         public function print_scripts() {
 659                 /** This action is documented in wp-admin/admin-header.php */
 660                 do_action( 'admin_print_scripts-widgets.php' );
 661
 662                 /** This action is documented in wp-admin/admin-header.php */
 663                 do_action( 'admin_print_scripts' );
 664         }
 665
 666         /**
 667          * Enqueue scripts and styles for customizer panel and export data to JavaScript.
 668          *
 669          * @since 3.9.0
 670          * @access public
 671          */
 672         public function enqueue_scripts() {
 673                 wp_enqueue_style( 'customize-widgets' );
 674                 wp_enqueue_script( 'customize-widgets' );
 675
 676                 /** This action is documented in wp-admin/admin-header.php */
 677                 do_action( 'admin_enqueue_scripts', 'widgets.php' );
 678
 679                 /*
 680                  * Export available widgets with control_tpl removed from model
 681                  * since plugins need templates to be in the DOM.
 682                  */
 683                 $available_widgets = array();
 684
 685                 foreach ( $this->get_available_widgets() as $available_widget ) {
 686                         unset( $available_widget['control_tpl'] );
 687                         $available_widgets[] = $available_widget;
 688                 }
 689
 690                 $widget_reorder_nav_tpl = sprintf(
 691                         '<div class="widget-reorder-nav"><span class="move-widget" tabindex="0">%1$s</span><span class="move-widget-down" tabindex="0">%2$s</span><span class="move-widget-up" tabindex="0">%3$s</span></div>',
 692                         __( 'Move to another area&hellip;' ),
 693                         __( 'Move down' ),
 694                         __( 'Move up' )
 695                 );
 696
 697                 $move_widget_area_tpl = str_replace(
 698                         array( '{description}', '{btn}' ),
 699                         array(
 700                                 __( 'Select an area to move this widget into:' ),
 701                                 _x( 'Move', 'Move widget' ),
 702                         ),
 703                         '<div class="move-widget-area">
 704                                 <p class="description">{description}</p>
 705                                 <ul class="widget-area-select">
 706                                         <% _.each( sidebars, function ( sidebar ){ %>
 707                                                 <li class="" data-id="<%- sidebar.id %>" title="<%- sidebar.description %>" tabindex="0"><%- sidebar.name %></li>
 708                                         <% }); %>
 709                                 </ul>
 710                                 <div class="move-widget-actions">
 711                                         <button class="move-widget-btn button-secondary" type="button">{btn}</button>
 712                                 </div>
 713                         </div>'
 714                 );
 715
 716                 global $wp_scripts;
 717
 718                 $settings = array(
 719                         'nonce'                => wp_create_nonce( 'update-widget' ),
 720                         'registeredSidebars'   => array_values( $GLOBALS['wp_registered_sidebars'] ),
 721                         'registeredWidgets'    => $GLOBALS['wp_registered_widgets'],
 722                         'availableWidgets'     => $available_widgets, // @todo Merge this with registered_widgets
 723                         'l10n' => array(
 724                                 'saveBtnLabel'     => __( 'Apply' ),
 725                                 'saveBtnTooltip'   => __( 'Save and preview changes before publishing them.' ),
 726                                 'removeBtnLabel'   => __( 'Remove' ),
 727                                 'removeBtnTooltip' => __( 'Trash widget by moving it to the inactive widgets sidebar.' ),
 728                                 'error'            => __( 'An error has occurred. Please reload the page and try again.' ),
 729                         ),
 730                         'tpl' => array(
 731                                 'widgetReorderNav' => $widget_reorder_nav_tpl,
 732                                 'moveWidgetArea'   => $move_widget_area_tpl,
 733                         ),
 734                 );
 735
 736                 foreach ( $settings['registeredWidgets'] as &$registered_widget ) {
 737                         unset( $registered_widget['callback'] ); // may not be JSON-serializeable
 738                 }
 739
 740                 $wp_scripts->add_data(
 741                         'customize-widgets',
 742                         'data',
 743                         sprintf( 'var _wpCustomizeWidgetsSettings = %s;', json_encode( $settings ) )
 744                 );
 745         }
 746
 747         /**
 748          * Render the widget form control templates into the DOM.
 749          *
 750          * @since 3.9.0
 751          * @access public
 752          */
 753         public function output_widget_control_templates() {
 754                 ?>
 755                 <div id="widgets-left"><!-- compatibility with JS which looks for widget templates here -->
 756                 <div id="available-widgets">
 757                         <div id="available-widgets-filter">
 758                                 <label class="screen-reader-text" for="widgets-search"><?php _e( 'Search Widgets' ); ?></label>
 759                                 <input type="search" id="widgets-search" placeholder="<?php esc_attr_e( 'Search widgets&hellip;' ) ?>" />
 760                         </div>
 761                         <?php foreach ( $this->get_available_widgets() as $available_widget ): ?>
 762                                 <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">
 763                                         <?php echo $available_widget['control_tpl']; ?>
 764                                 </div>
 765                         <?php endforeach; ?>
 766                 </div><!-- #available-widgets -->
 767                 </div><!-- #widgets-left -->
 768                 <?php
 769         }
 770
 771         /**
 772          * Call admin_print_footer_scripts and admin_print_scripts hooks to
 773          * allow custom scripts from plugins.
 774          *
 775          * @since 3.9.0
 776          * @access public
 777          */
 778         public function print_footer_scripts() {
 779                 /** This action is documented in wp-admin/admin-footer.php */
 780                 do_action( 'admin_print_footer_scripts' );
 781
 782                 /** This action is documented in wp-admin/admin-footer.php */
 783                 do_action( 'admin_footer-widgets.php' );
 784         }
 785
 786         /**
 787          * Get common arguments to supply when constructing a Customizer setting.
 788          *
 789          * @since 3.9.0
 790          * @access public
 791          *
 792          * @param string $id        Widget setting ID.
 793          * @param array  $overrides Array of setting overrides.
 794          * @return array Possibly modified setting arguments.
 795          */
 796         public function get_setting_args( $id, $overrides = array() ) {
 797                 $args = array(
 798                         'type'       => 'option',
 799                         'capability' => 'edit_theme_options',
 800                         'transport'  => 'refresh',
 801                         'default'    => array(),
 802                 );
 803                 $args = array_merge( $args, $overrides );
 804
 805                 /**
 806                  * Filter the common arguments supplied when constructing a Customizer setting.
 807                  *
 808                  * @since 3.9.0
 809                  *
 810                  * @see WP_Customize_Setting
 811                  *
 812                  * @param array  $args Array of Customizer setting arguments.
 813                  * @param string $id   Widget setting ID.
 814                  */
 815                 return apply_filters( 'widget_customizer_setting_args', $args, $id );
 816         }
 817
 818         /**
 819          * Make sure that sidebar widget arrays only ever contain widget IDS.
 820          *
 821          * Used as the 'sanitize_callback' for each $sidebars_widgets setting.
 822          *
 823          * @since 3.9.0
 824          * @access public
 825          *
 826          * @param array $widget_ids Array of widget IDs.
 827          * @return array Array of sanitized widget IDs.
 828          */
 829         public function sanitize_sidebar_widgets( $widget_ids ) {
 830                 global $wp_registered_widgets;
 831
 832                 $widget_ids           = array_map( 'strval', (array) $widget_ids );
 833                 $sanitized_widget_ids = array();
 834
 835                 foreach ( $widget_ids as $widget_id ) {
 836                         if ( array_key_exists( $widget_id, $wp_registered_widgets ) ) {
 837                                 $sanitized_widget_ids[] = $widget_id;
 838                         }
 839                 }
 840                 return $sanitized_widget_ids;
 841         }
 842
 843         /**
 844          * Build up an index of all available widgets for use in Backbone models.
 845          *
 846          * @since 3.9.0
 847          * @access public
 848          *
 849          * @see wp_list_widgets()
 850          *
 851          * @return array List of available widgets.
 852          */
 853         public function get_available_widgets() {
 854                 static $available_widgets = array();
 855                 if ( ! empty( $available_widgets ) ) {
 856                         return $available_widgets;
 857                 }
 858
 859                 global $wp_registered_widgets, $wp_registered_widget_controls;
 860                 require_once ABSPATH . '/wp-admin/includes/widgets.php'; // for next_widget_id_number()
 861
 862                 $sort = $wp_registered_widgets;
 863                 usort( $sort, array( $this, '_sort_name_callback' ) );
 864                 $done = array();
 865
 866                 foreach ( $sort as $widget ) {
 867                         if ( in_array( $widget['callback'], $done, true ) ) { // We already showed this multi-widget
 868                                 continue;
 869                         }
 870
 871                         $sidebar = is_active_widget( $widget['callback'], $widget['id'], false, false );
 872                         $done[]  = $widget['callback'];
 873
 874                         if ( ! isset( $widget['params'][0] ) ) {
 875                                 $widget['params'][0] = array();
 876                         }
 877
 878                         $available_widget = $widget;
 879                         unset( $available_widget['callback'] ); // not serializable to JSON
 880
 881                         $args = array(
 882                                 'widget_id'   => $widget['id'],
 883                                 'widget_name' => $widget['name'],
 884                                 '_display'    => 'template',
 885                         );
 886
 887                         $is_disabled     = false;
 888                         $is_multi_widget = ( isset( $wp_registered_widget_controls[$widget['id']]['id_base'] ) && isset( $widget['params'][0]['number'] ) );
 889                         if ( $is_multi_widget ) {
 890                                 $id_base            = $wp_registered_widget_controls[$widget['id']]['id_base'];
 891                                 $args['_temp_id']   = "$id_base-__i__";
 892                                 $args['_multi_num'] = next_widget_id_number( $id_base );
 893                                 $args['_add']       = 'multi';
 894                         } else {
 895                                 $args['_add'] = 'single';
 896
 897                                 if ( $sidebar && 'wp_inactive_widgets' !== $sidebar ) {
 898                                         $is_disabled = true;
 899                                 }
 900                                 $id_base = $widget['id'];
 901                         }
 902
 903                         $list_widget_controls_args = wp_list_widget_controls_dynamic_sidebar( array( 0 => $args, 1 => $widget['params'][0] ) );
 904                         $control_tpl = $this->get_widget_control( $list_widget_controls_args );
 905
 906                         // The properties here are mapped to the Backbone Widget model.
 907                         $available_widget = array_merge( $available_widget, array(
 908                                 'temp_id'      => isset( $args['_temp_id'] ) ? $args['_temp_id'] : null,
 909                                 'is_multi'     => $is_multi_widget,
 910                                 'control_tpl'  => $control_tpl,
 911                                 'multi_number' => ( $args['_add'] === 'multi' ) ? $args['_multi_num'] : false,
 912                                 'is_disabled'  => $is_disabled,
 913                                 'id_base'      => $id_base,
 914                                 'transport'    => 'refresh',
 915                                 'width'        => $wp_registered_widget_controls[$widget['id']]['width'],
 916                                 'height'       => $wp_registered_widget_controls[$widget['id']]['height'],
 917                                 'is_wide'      => $this->is_wide_widget( $widget['id'] ),
 918                         ) );
 919
 920                         $available_widgets[] = $available_widget;
 921                 }
 922
 923                 return $available_widgets;
 924         }
 925
 926         /**
 927          * Naturally order available widgets by name.
 928          *
 929          * @since 3.9.0
 930          * @static
 931          * @access protected
 932          *
 933          * @param array $widget_a The first widget to compare.
 934          * @param array $widget_b The second widget to compare.
 935          * @return int Reorder position for the current widget comparison.
 936          */
 937         protected function _sort_name_callback( $widget_a, $widget_b ) {
 938                 return strnatcasecmp( $widget_a['name'], $widget_b['name'] );
 939         }
 940
 941         /**
 942          * Get the widget control markup.
 943          *
 944          * @since 3.9.0
 945          * @access public
 946          *
 947          * @param array $args Widget control arguments.
 948          * @return string Widget control form HTML markup.
 949          */
 950         public function get_widget_control( $args ) {
 951                 ob_start();
 952
 953                 call_user_func_array( 'wp_widget_control', $args );
 954                 $replacements = array(
 955                         '<form action="" method="post">' => '<div class="form">',
 956                         '</form>' => '</div><!-- .form -->',
 957                 );
 958
 959                 $control_tpl = ob_get_clean();
 960
 961                 $control_tpl = str_replace( array_keys( $replacements ), array_values( $replacements ), $control_tpl );
 962
 963                 return $control_tpl;
 964         }
 965
 966         /**
 967          * Add hooks for the customizer preview.
 968          *
 969          * @since 3.9.0
 970          * @access public
 971          */
 972         public function customize_preview_init() {
 973                 add_filter( 'sidebars_widgets',   array( $this, 'preview_sidebars_widgets' ), 1 );
 974                 add_action( 'wp_enqueue_scripts', array( $this, 'customize_preview_enqueue' ) );
 975                 add_action( 'wp_print_styles',    array( $this, 'print_preview_css' ), 1 );
 976                 add_action( 'wp_footer',          array( $this, 'export_preview_data' ), 20 );
 977         }
 978
 979         /**
 980          * When previewing, make sure the proper previewing widgets are used.
 981          *
 982          * Because wp_get_sidebars_widgets() gets called early at init
 983          * (via wp_convert_widget_settings()) and can set global variable
 984          * $_wp_sidebars_widgets to the value of get_option( 'sidebars_widgets' )
 985          * before the customizer preview filter is added, we have to reset
 986          * it after the filter has been added.
 987          *
 988          * @since 3.9.0
 989          * @access public
 990          *
 991          * @param array $sidebars_widgets List of widgets for the current sidebar.
 992          */
 993         public function preview_sidebars_widgets( $sidebars_widgets ) {
 994                 $sidebars_widgets = get_option( 'sidebars_widgets' );
 995
 996                 unset( $sidebars_widgets['array_version'] );
 997                 return $sidebars_widgets;
 998         }
 999
1000         /**
1001          * Enqueue scripts for the Customizer preview.
1002          *
1003          * @since 3.9.0
1004          * @access public
1005          */
1006         public function customize_preview_enqueue() {
1007                 wp_enqueue_script( 'customize-preview-widgets' );
1008         }
1009
1010         /**
1011          * Insert default style for highlighted widget at early point so theme
1012          * stylesheet can override.
1013          *
1014          * @since 3.9.0
1015          * @access public
1016          *
1017          * @action wp_print_styles
1018          */
1019         public function print_preview_css() {
1020                 ?>
1021                 <style>
1022                 .widget-customizer-highlighted-widget {
1023                         outline: none;
1024                         -webkit-box-shadow: 0 0 2px rgba(30,140,190,0.8);
1025                         box-shadow: 0 0 2px rgba(30,140,190,0.8);
1026                         position: relative;
1027                         z-index: 1;
1028                 }
1029                 </style>
1030                 <?php
1031         }
1032
1033         /**
1034          * At the very end of the page, at the very end of the wp_footer,
1035          * communicate the sidebars that appeared on the page.
1036          *
1037          * @since 3.9.0
1038          * @access public
1039          */
1040         public function export_preview_data() {
1041
1042                 // Prepare customizer settings to pass to Javascript.
1043                 $settings = array(
1044                         'renderedSidebars'   => array_fill_keys( array_unique( $this->rendered_sidebars ), true ),
1045                         'renderedWidgets'    => array_fill_keys( array_keys( $this->rendered_widgets ), true ),
1046                         'registeredSidebars' => array_values( $GLOBALS['wp_registered_sidebars'] ),
1047                         'registeredWidgets'  => $GLOBALS['wp_registered_widgets'],
1048                         'l10n'               => array(
1049                                 'widgetTooltip' => __( 'Shift-click to edit this widget.' ),
1050                         ),
1051                 );
1052                 foreach ( $settings['registeredWidgets'] as &$registered_widget ) {
1053                         unset( $registered_widget['callback'] ); // may not be JSON-serializeable
1054                 }
1055
1056                 ?>
1057                 <script type="text/javascript">
1058                         var _wpWidgetCustomizerPreviewSettings = <?php echo json_encode( $settings ); ?>;
1059                 </script>
1060                 <?php
1061         }
1062
1063         /**
1064          * Keep track of the widgets that were rendered.
1065          *
1066          * @since 3.9.0
1067          * @access public
1068          *
1069          * @param array $widget Rendered widget to tally.
1070          */
1071         public function tally_rendered_widgets( $widget ) {
1072                 $this->rendered_widgets[ $widget['id'] ] = true;
1073         }
1074
1075         /**
1076          * Determine if a widget is rendered on the page.
1077          *
1078          * @since 4.0.0
1079          * @access public
1080          *
1081          * @param string $widget_id Widget ID to check.
1082          * @return bool Whether the widget is rendered.
1083          */
1084         public function is_widget_rendered( $widget_id ) {
1085                 return in_array( $widget_id, $this->rendered_widgets );
1086         }
1087
1088         /**
1089          * Determine if a sidebar is rendered on the page.
1090          *
1091          * @since 4.0.0
1092          * @access public
1093          *
1094          * @param string $sidebar_id Sidebar ID to check.
1095          * @return bool Whether the sidebar is rendered.
1096          */
1097         public function is_sidebar_rendered( $sidebar_id ) {
1098                 return in_array( $sidebar_id, $this->rendered_sidebars );
1099         }
1100
1101         /**
1102          * Tally the sidebars rendered via is_active_sidebar().
1103          *
1104          * Keep track of the times that is_active_sidebar() is called
1105          * in the template, and assume that this means that the sidebar
1106          * would be rendered on the template if there were widgets
1107          * populating it.
1108          *
1109          * @since 3.9.0
1110          * @access public
1111          *
1112          * @param bool   $is_active  Whether the sidebar is active.
1113          * @param string $sidebar_id Sidebar ID.
1114          */
1115         public function tally_sidebars_via_is_active_sidebar_calls( $is_active, $sidebar_id ) {
1116                 if ( isset( $GLOBALS['wp_registered_sidebars'][$sidebar_id] ) ) {
1117                         $this->rendered_sidebars[] = $sidebar_id;
1118                 }
1119                 /*
1120                  * We may need to force this to true, and also force-true the value
1121                  * for 'dynamic_sidebar_has_widgets' if we want to ensure that there
1122                  * is an area to drop widgets into, if the sidebar is empty.
1123                  */
1124                 return $is_active;
1125         }
1126
1127         /**
1128          * Tally the sidebars rendered via dynamic_sidebar().
1129          *
1130          * Keep track of the times that dynamic_sidebar() is called in the template,
1131          * and assume this means the sidebar would be rendered on the template if
1132          * there were widgets populating it.
1133          *
1134          * @since 3.9.0
1135          * @access public
1136          *
1137          * @param bool   $has_widgets Whether the current sidebar has widgets.
1138          * @param string $sidebar_id  Sidebar ID.
1139          */
1140         public function tally_sidebars_via_dynamic_sidebar_calls( $has_widgets, $sidebar_id ) {
1141                 if ( isset( $GLOBALS['wp_registered_sidebars'][$sidebar_id] ) ) {
1142                         $this->rendered_sidebars[] = $sidebar_id;
1143                 }
1144
1145                 /*
1146                  * We may need to force this to true, and also force-true the value
1147                  * for 'is_active_sidebar' if we want to ensure there is an area to
1148                  * drop widgets into, if the sidebar is empty.
1149                  */
1150                 return $has_widgets;
1151         }
1152
1153         /**
1154          * Get MAC for a serialized widget instance string.
1155          *
1156          * Allows values posted back from JS to be rejected if any tampering of the
1157          * data has occurred.
1158          *
1159          * @since 3.9.0
1160          * @access protected
1161          *
1162          * @param string $serialized_instance Widget instance.
1163          * @return string MAC for serialized widget instance.
1164          */
1165         protected function get_instance_hash_key( $serialized_instance ) {
1166                 return wp_hash( $serialized_instance );
1167         }
1168
1169         /**
1170          * Sanitize a widget instance.
1171          *
1172          * Unserialize the JS-instance for storing in the options. It's important
1173          * that this filter only get applied to an instance once.
1174          *
1175          * @since 3.9.0
1176          * @access public
1177          *
1178          * @param array $value Widget instance to sanitize.
1179          * @return array Sanitized widget instance.
1180          */
1181         public function sanitize_widget_instance( $value ) {
1182                 if ( $value === array() ) {
1183                         return $value;
1184                 }
1185
1186                 if ( empty( $value['is_widget_customizer_js_value'] )
1187                         || empty( $value['instance_hash_key'] )
1188                         || empty( $value['encoded_serialized_instance'] ) )
1189                 {
1190                         return null;
1191                 }
1192
1193                 $decoded = base64_decode( $value['encoded_serialized_instance'], true );
1194                 if ( false === $decoded ) {
1195                         return null;
1196                 }
1197
1198                 if ( $this->get_instance_hash_key( $decoded ) !== $value['instance_hash_key'] ) {
1199                         return null;
1200                 }
1201
1202                 $instance = unserialize( $decoded );
1203                 if ( false === $instance ) {
1204                         return null;
1205                 }
1206
1207                 return $instance;
1208         }
1209
1210         /**
1211          * Convert widget instance into JSON-representable format.
1212          *
1213          * @since 3.9.0
1214          * @access public
1215          *
1216          * @param array $value Widget instance to convert to JSON.
1217          * @return array JSON-converted widget instance.
1218          */
1219         public function sanitize_widget_js_instance( $value ) {
1220                 if ( empty( $value['is_widget_customizer_js_value'] ) ) {
1221                         $serialized = serialize( $value );
1222
1223                         $value = array(
1224                                 'encoded_serialized_instance'   => base64_encode( $serialized ),
1225                                 'title'                         => empty( $value['title'] ) ? '' : $value['title'],
1226                                 'is_widget_customizer_js_value' => true,
1227                                 'instance_hash_key'             => $this->get_instance_hash_key( $serialized ),
1228                         );
1229                 }
1230                 return $value;
1231         }
1232
1233         /**
1234          * Strip out widget IDs for widgets which are no longer registered.
1235          *
1236          * One example where this might happen is when a plugin orphans a widget
1237          * in a sidebar upon deactivation.
1238          *
1239          * @since 3.9.0
1240          * @access public
1241          *
1242          * @param array $widget_ids List of widget IDs.
1243          * @return array Parsed list of widget IDs.
1244          */
1245         public function sanitize_sidebar_widgets_js_instance( $widget_ids ) {
1246                 global $wp_registered_widgets;
1247                 $widget_ids = array_values( array_intersect( $widget_ids, array_keys( $wp_registered_widgets ) ) );
1248                 return $widget_ids;
1249         }
1250
1251         /**
1252          * Find and invoke the widget update and control callbacks.
1253          *
1254          * Requires that $_POST be populated with the instance data.
1255          *
1256          * @since 3.9.0
1257          * @access public
1258          *
1259          * @param  string $widget_id Widget ID.
1260          * @return WP_Error|array Array containing the updated widget information.
1261          *                        A WP_Error object, otherwise.
1262          */
1263         public function call_widget_update( $widget_id ) {
1264                 global $wp_registered_widget_updates, $wp_registered_widget_controls;
1265
1266                 $this->start_capturing_option_updates();
1267                 $parsed_id   = $this->parse_widget_id( $widget_id );
1268                 $option_name = 'widget_' . $parsed_id['id_base'];
1269
1270                 /*
1271                  * If a previously-sanitized instance is provided, populate the input vars
1272                  * with its values so that the widget update callback will read this instance
1273                  */
1274                 $added_input_vars = array();
1275                 if ( ! empty( $_POST['sanitized_widget_setting'] ) ) {
1276                         $sanitized_widget_setting = json_decode( $this->get_post_value( 'sanitized_widget_setting' ), true );
1277                         if ( false === $sanitized_widget_setting ) {
1278                                 $this->stop_capturing_option_updates();
1279                                 return new WP_Error( 'widget_setting_malformed' );
1280                         }
1281
1282                         $instance = $this->sanitize_widget_instance( $sanitized_widget_setting );
1283                         if ( is_null( $instance ) ) {
1284                                 $this->stop_capturing_option_updates();
1285                                 return new WP_Error( 'widget_setting_unsanitized' );
1286                         }
1287
1288                         if ( ! is_null( $parsed_id['number'] ) ) {
1289                                 $value = array();
1290                                 $value[$parsed_id['number']] = $instance;
1291                                 $key = 'widget-' . $parsed_id['id_base'];
1292                                 $_REQUEST[$key] = $_POST[$key] = wp_slash( $value );
1293                                 $added_input_vars[] = $key;
1294                         } else {
1295                                 foreach ( $instance as $key => $value ) {
1296                                         $_REQUEST[$key] = $_POST[$key] = wp_slash( $value );
1297                                         $added_input_vars[] = $key;
1298                                 }
1299                         }
1300                 }
1301
1302                 // Invoke the widget update callback.
1303                 foreach ( (array) $wp_registered_widget_updates as $name => $control ) {
1304                         if ( $name === $parsed_id['id_base'] && is_callable( $control['callback'] ) ) {
1305                                 ob_start();
1306                                 call_user_func_array( $control['callback'], $control['params'] );
1307                                 ob_end_clean();
1308                                 break;
1309                         }
1310                 }
1311
1312                 // Clean up any input vars that were manually added
1313                 foreach ( $added_input_vars as $key ) {
1314                         unset( $_POST[$key] );
1315                         unset( $_REQUEST[$key] );
1316                 }
1317
1318                 // Make sure the expected option was updated.
1319                 if ( 0 !== $this->count_captured_options() ) {
1320                         if ( $this->count_captured_options() > 1 ) {
1321                                 $this->stop_capturing_option_updates();
1322                                 return new WP_Error( 'widget_setting_too_many_options' );
1323                         }
1324
1325                         $updated_option_name = key( $this->get_captured_options() );
1326                         if ( $updated_option_name !== $option_name ) {
1327                                 $this->stop_capturing_option_updates();
1328                                 return new WP_Error( 'widget_setting_unexpected_option' );
1329                         }
1330                 }
1331
1332                 // Obtain the widget control with the updated instance in place.
1333                 ob_start();
1334
1335                 $form = $wp_registered_widget_controls[$widget_id];
1336                 if ( $form ) {
1337                         call_user_func_array( $form['callback'], $form['params'] );
1338                 }
1339
1340                 $form = ob_get_clean();
1341
1342                 // Obtain the widget instance.
1343                 $option = get_option( $option_name );
1344
1345                 if ( null !== $parsed_id['number'] ) {
1346                         $instance = $option[$parsed_id['number']];
1347                 } else {
1348                         $instance = $option;
1349                 }
1350
1351                 $this->stop_capturing_option_updates();
1352
1353                 return compact( 'instance', 'form' );
1354         }
1355
1356         /**
1357          * Update widget settings asynchronously.
1358          *
1359          * Allows the Customizer to update a widget using its form, but return the new
1360          * instance info via Ajax instead of saving it to the options table.
1361          *
1362          * Most code here copied from wp_ajax_save_widget()
1363          *
1364          * @since 3.9.0
1365          * @access public
1366          *
1367          * @see wp_ajax_save_widget()
1368          *
1369          */
1370         public function wp_ajax_update_widget() {
1371
1372                 if ( ! is_user_logged_in() ) {
1373                         wp_die( 0 );
1374                 }
1375
1376                 check_ajax_referer( 'update-widget', 'nonce' );
1377
1378                 if ( ! current_user_can( 'edit_theme_options' ) ) {
1379                         wp_die( -1 );
1380                 }
1381
1382                 if ( ! isset( $_POST['widget-id'] ) ) {
1383                         wp_send_json_error();
1384                 }
1385
1386                 /** This action is documented in wp-admin/includes/ajax-actions.php */
1387                 do_action( 'load-widgets.php' );
1388
1389                 /** This action is documented in wp-admin/includes/ajax-actions.php */
1390                 do_action( 'widgets.php' );
1391
1392                 /** This action is documented in wp-admin/widgets.php */
1393                 do_action( 'sidebar_admin_setup' );
1394
1395                 $widget_id = $this->get_post_value( 'widget-id' );
1396                 $parsed_id = $this->parse_widget_id( $widget_id );
1397                 $id_base   = $parsed_id['id_base'];
1398
1399                 if ( isset( $_POST['widget-' . $id_base] ) && is_array( $_POST['widget-' . $id_base] ) && preg_match( '/__i__|%i%/', key( $_POST['widget-' . $id_base] ) ) ) {
1400                         wp_send_json_error();
1401                 }
1402
1403                 $updated_widget = $this->call_widget_update( $widget_id ); // => {instance,form}
1404                 if ( is_wp_error( $updated_widget ) ) {
1405                         wp_send_json_error();
1406                 }
1407
1408                 $form = $updated_widget['form'];
1409                 $instance = $this->sanitize_widget_js_instance( $updated_widget['instance'] );
1410
1411                 wp_send_json_success( compact( 'form', 'instance' ) );
1412         }
1413
1414         /***************************************************************************
1415          * Option Update Capturing
1416          ***************************************************************************/
1417
1418         /**
1419          * List of captured widget option updates.
1420          *
1421          * @since 3.9.0
1422          * @access protected
1423          * @var array $_captured_options Values updated while option capture is happening.
1424          */
1425         protected $_captured_options = array();
1426
1427         /**
1428          * Whether option capture is currently happening.
1429          *
1430          * @since 3.9.0
1431          * @access protected
1432          * @var bool $_is_current Whether option capture is currently happening or not.
1433          */
1434         protected $_is_capturing_option_updates = false;
1435
1436         /**
1437          * Determine whether the captured option update should be ignored.
1438          *
1439          * @since 3.9.0
1440          * @access protected
1441          *
1442          * @param string $option_name Option name.
1443          * @return boolean Whether the option capture is ignored.
1444          */
1445         protected function is_option_capture_ignored( $option_name ) {
1446                 return ( 0 === strpos( $option_name, '_transient_' ) );
1447         }
1448
1449         /**
1450          * Retrieve captured widget option updates.
1451          *
1452          * @since 3.9.0
1453          * @access protected
1454          *
1455          * @return array Array of captured options.
1456          */
1457         protected function get_captured_options() {
1458                 return $this->_captured_options;
1459         }
1460
1461         /**
1462          * Get the number of captured widget option updates.
1463          *
1464          * @since 3.9.0
1465          * @access protected
1466          *
1467          * @return int Number of updated options.
1468          */
1469         protected function count_captured_options() {
1470                 return count( $this->_captured_options );
1471         }
1472
1473         /**
1474          * Start keeping track of changes to widget options, caching new values.
1475          *
1476          * @since 3.9.0
1477          * @access protected
1478          */
1479         protected function start_capturing_option_updates() {
1480                 if ( $this->_is_capturing_option_updates ) {
1481                         return;
1482                 }
1483
1484                 $this->_is_capturing_option_updates = true;
1485
1486                 add_filter( 'pre_update_option', array( $this, 'capture_filter_pre_update_option' ), 10, 3 );
1487         }
1488
1489         /**
1490          * Pre-filter captured option values before updating.
1491          *
1492          * @since 3.9.0
1493          * @access public
1494          *
1495          * @param mixed $new_value
1496          * @param string $option_name
1497          * @param mixed $old_value
1498          * @return mixed
1499          */
1500         public function capture_filter_pre_update_option( $new_value, $option_name, $old_value ) {
1501                 if ( $this->is_option_capture_ignored( $option_name ) ) {
1502                         return;
1503                 }
1504
1505                 if ( ! isset( $this->_captured_options[$option_name] ) ) {
1506                         add_filter( "pre_option_{$option_name}", array( $this, 'capture_filter_pre_get_option' ) );
1507                 }
1508
1509                 $this->_captured_options[$option_name] = $new_value;
1510
1511                 return $old_value;
1512         }
1513
1514         /**
1515          * Pre-filter captured option values before retrieving.
1516          *
1517          * @since 3.9.0
1518          * @access public
1519          *
1520          * @param mixed $value Option
1521          * @return mixed
1522          */
1523         public function capture_filter_pre_get_option( $value ) {
1524                 $option_name = preg_replace( '/^pre_option_/', '', current_filter() );
1525
1526                 if ( isset( $this->_captured_options[$option_name] ) ) {
1527                         $value = $this->_captured_options[$option_name];
1528
1529                         /** This filter is documented in wp-includes/option.php */
1530                         $value = apply_filters( 'option_' . $option_name, $value );
1531                 }
1532
1533                 return $value;
1534         }
1535
1536         /**
1537          * Undo any changes to the options since options capture began.
1538          *
1539          * @since 3.9.0
1540          * @access protected
1541          */
1542         protected function stop_capturing_option_updates() {
1543                 if ( ! $this->_is_capturing_option_updates ) {
1544                         return;
1545                 }
1546
1547                 remove_filter( 'pre_update_option', array( $this, 'capture_filter_pre_update_option' ), 10, 3 );
1548
1549                 foreach ( array_keys( $this->_captured_options ) as $option_name ) {
1550                         remove_filter( "pre_option_{$option_name}", array( $this, 'capture_filter_pre_get_option' ) );
1551                 }
1552
1553                 $this->_captured_options = array();
1554                 $this->_is_capturing_option_updates = false;
1555         }
1556 }