<?php

/**

 * Widget API: WP_Widget base class

 *

 * @package WordPress

 * @subpackage Widgets

 * @since 4.4.0

 */

/**

 * Core base class extended to register widgets.

 *

 * This class must be extended for each widget, and WP_Widget::widget() must be overridden.

 *

 * If adding widget options, WP_Widget::update() and WP_Widget::form() should also be overridden.

 *

 * @since 2.8.0

 * @since 4.4.0 Moved to its own file from wp-includes/widgets.php

 */

class WP_Widget {

	/**

	 * Root ID for all widgets of this type.

	 *

	 * @since 2.8.0

	 * @var mixed|string

	 */

	public $id_base;

	/**

	 * Name for this widget type.

	 *

	 * @since 2.8.0

	 * @var string

	 */

	public $name;

	/**

	 * Option name for this widget type.

	 *

	 * @since 2.8.0

	 * @var string

	 */

	public $option_name;

	/**

	 * Alt option name for this widget type.

	 *

	 * @since 2.8.0

	 * @var string

	 */

	public $alt_option_name;

	/**

	 * Option array passed to wp_register_sidebar_widget().

	 *

	 * @since 2.8.0

	 * @var array

	 */

	public $widget_options;

	/**

	 * Option array passed to wp_register_widget_control().

	 *

	 * @since 2.8.0

	 * @var array

	 */

	public $control_options;

	/**

	 * Unique ID number of the current instance.

	 *

	 * @since 2.8.0

	 * @var bool|int

	 */

	public $number = false;

	/**

	 * Unique ID string of the current instance (id_base-number).

	 *

	 * @since 2.8.0

	 * @var bool|string

	 */

	public $id = false;

	/**

	 * Whether the widget data has been updated.

	 *

	 * Set to true when the data is updated after a POST submit - ensures it does

	 * not happen twice.

	 *

	 * @since 2.8.0

	 * @var bool

	 */

	public $updated = false;

	//

	// Member functions that must be overridden by subclasses.

	//

	/**

	 * Echoes the widget content.

	 *

	 * Sub-classes should over-ride this function to generate their widget code.

	 *

	 * @since 2.8.0

	 *

	 * @param array $args     Display arguments including 'before_title', 'after_title',

	 *                        'before_widget', and 'after_widget'.

	 * @param array $instance The settings for the particular instance of the widget.

	 */

	public function widget( $args, $instance ) {

		die('function WP_Widget::widget() must be over-ridden in a sub-class.');

	}

	/**

	 * Updates a particular instance of a widget.

	 *

	 * This function should check that `$new_instance` is set correctly. The newly-calculated

	 * value of `$instance` should be returned. If false is returned, the instance won't be

	 * saved/updated.

	 *

	 * @since 2.8.0

	 *

	 * @param array $new_instance New settings for this instance as input by the user via

	 *                            WP_Widget::form().

	 * @param array $old_instance Old settings for this instance.

	 * @return array Settings to save or bool false to cancel saving.

	 */

	public function update( $new_instance, $old_instance ) {

		return $new_instance;

	}

	/**

	 * Outputs the settings update form.

	 *

	 * @since 2.8.0

	 *

	 * @param array $instance Current settings.

	 * @return string Default return is 'noform'.

	 */

	public function form( $instance ) {

		echo '<p class="no-options-widget">' . __('There are no options for this widget.') . '</p>';

		return 'noform';

	}

	// Functions you'll need to call.

	/**

	 * PHP5 constructor.

	 *

	 * @since 2.8.0

	 *

	 * @param string $id_base         Optional Base ID for the widget, lowercase and unique. If left empty,

	 *                                a portion of the widget's class name will be used Has to be unique.

	 * @param string $name            Name for the widget displayed on the configuration page.

	 * @param array  $widget_options  Optional. Widget options. See wp_register_sidebar_widget() for information

	 *                                on accepted arguments. Default empty array.

	 * @param array  $control_options Optional. Widget control options. See wp_register_widget_control() for

	 *                                information on accepted arguments. Default empty array.

	 */

	public function __construct( $id_base, $name, $widget_options = array(), $control_options = array() ) {

		$this->id_base = empty($id_base) ? preg_replace( '/(wp_)?widget_/', '', strtolower(get_class($this)) ) : strtolower($id_base);

		$this->name = $name;

		$this->option_name = 'widget_' . $this->id_base;

		$this->widget_options = wp_parse_args( $widget_options, array( 'classname' => $this->option_name, 'customize_selective_refresh' => false ) );

		$this->control_options = wp_parse_args( $control_options, array( 'id_base' => $this->id_base ) );

	}

	/**

	 * PHP4 constructor.

	 *

	 * @since 2.8.0

	 *

	 * @see __construct()

	 *

	 * @param string $id_base         Optional Base ID for the widget, lowercase and unique. If left empty,

	 *                                a portion of the widget's class name will be used Has to be unique.

	 * @param string $name            Name for the widget displayed on the configuration page.

	 * @param array  $widget_options  Optional. Widget options. See wp_register_sidebar_widget() for information

	 *                                on accepted arguments. Default empty array.

	 * @param array  $control_options Optional. Widget control options. See wp_register_widget_control() for

	 *                                information on accepted arguments. Default empty array.

	 */

	public function WP_Widget( $id_base, $name, $widget_options = array(), $control_options = array() ) {

		_deprecated_constructor( 'WP_Widget', '4.3.0', get_class( $this ) );

		WP_Widget::__construct( $id_base, $name, $widget_options, $control_options );

	}

	/**

	 * Constructs name attributes for use in form() fields

	 *

	 * This function should be used in form() methods to create name attributes for fields

	 * to be saved by update()

	 *

	 * @since 2.8.0

	 * @since 4.4.0 Array format field names are now accepted.

	 *

	 * @param string $field_name Field name

	 * @return string Name attribute for $field_name

	 */

	public function get_field_name($field_name) {

		if ( false === $pos = strpos( $field_name, '[' ) ) {

			return 'widget-' . $this->id_base . '[' . $this->number . '][' . $field_name . ']';

		} else {

			return 'widget-' . $this->id_base . '[' . $this->number . '][' . substr_replace( $field_name, '][', $pos, strlen( '[' ) );

		}

	}

	/**

	 * Constructs id attributes for use in WP_Widget::form() fields.

	 *

	 * This function should be used in form() methods to create id attributes

	 * for fields to be saved by WP_Widget::update().

	 *

	 * @since 2.8.0

	 * @since 4.4.0 Array format field IDs are now accepted.

	 *

	 * @param string $field_name Field name.

	 * @return string ID attribute for `$field_name`.

	 */

	public function get_field_id( $field_name ) {

		return 'widget-' . $this->id_base . '-' . $this->number . '-' . trim( str_replace( array( '[]', '[', ']' ), array( '', '-', '' ), $field_name ), '-' );

	}

	/**

	 * Register all widget instances of this widget class.

	 *

	 * @since 2.8.0

	 */

	public function _register() {

		$settings = $this->get_settings();

		$empty = true;

		// When $settings is an array-like object, get an intrinsic array for use with array_keys().

		if ( $settings instanceof ArrayObject || $settings instanceof ArrayIterator ) {

			$settings = $settings->getArrayCopy();

		}

		if ( is_array( $settings ) ) {

			foreach ( array_keys( $settings ) as $number ) {

				if ( is_numeric( $number ) ) {

					$this->_set( $number );

					$this->_register_one( $number );

					$empty = false;

				}

			}

		}

		if ( $empty ) {

			// If there are none, we register the widget's existence with a generic template.

			$this->_set( 1 );

			$this->_register_one();

		}

	}

	/**

	 * Sets the internal order number for the widget instance.

	 *

	 * @since 2.8.0

	 *

	 * @param int $number The unique order number of this widget instance compared to other

	 *                    instances of the same class.

	 */

	public function _set($number) {

		$this->number = $number;

		$this->id = $this->id_base . '-' . $number;

	}

	/**

	 * Retrieves the widget display callback.

	 *

	 * @since 2.8.0

	 *

	 * @return callable Display callback.

	 */

	public function _get_display_callback() {

		return array($this, 'display_callback');

	}

	/**

	 * Retrieves the widget update callback.

	 *

	 * @since 2.8.0

	 *

	 * @return callable Update callback.

	 */

	public function _get_update_callback() {

		return array($this, 'update_callback');

	}

	/**

	 * Retrieves the form callback.

	 *

	 * @since 2.8.0

	 *

	 * @return callable Form callback.

	 */

	public function _get_form_callback() {

		return array($this, 'form_callback');

	}

	/**

	 * Determines whether the current request is inside the Customizer preview.

	 *

	 * If true -- the current request is inside the Customizer preview, then

	 * the object cache gets suspended and widgets should check this to decide

	 * whether they should store anything persistently to the object cache,

	 * to transients, or anywhere else.

	 *

	 * @since 3.9.0

	 *

	 * @global WP_Customize_Manager $wp_customize

	 *

	 * @return bool True if within the Customizer preview, false if not.

	 */

	public function is_preview() {

		global $wp_customize;

		return ( isset( $wp_customize ) && $wp_customize->is_preview() ) ;

	}

	/**

	 * Generates the actual widget content (Do NOT override).

	 *

	 * Finds the instance and calls WP_Widget::widget().

	 *

	 * @since 2.8.0

	 *

	 * @param array     $args        Display arguments. See WP_Widget::widget() for information

	 *                               on accepted arguments.

	 * @param int|array $widget_args {

	 *     Optional. Internal order number of the widget instance, or array of multi-widget arguments.

	 *     Default 1.

	 *

	 *     @type int $number Number increment used for multiples of the same widget.

	 * }

	 */

	public function display_callback( $args, $widget_args = 1 ) {

		if ( is_numeric( $widget_args ) ) {

			$widget_args = array( 'number' => $widget_args );

		}

		$widget_args = wp_parse_args( $widget_args, array( 'number' => -1 ) );

		$this->_set( $widget_args['number'] );

		$instances = $this->get_settings();

		if ( array_key_exists( $this->number, $instances ) ) {

			$instance = $instances[ $this->number ];

			/**

			 * Filters the settings for a particular widget instance.

			 *

			 * Returning false will effectively short-circuit display of the widget.

			 *

			 * @since 2.8.0

			 *

			 * @param array     $instance The current widget instance's settings.

			 * @param WP_Widget $this     The current widget instance.

			 * @param array     $args     An array of default widget arguments.

			 */

			$instance = apply_filters( 'widget_display_callback', $instance, $this, $args );

			if ( false === $instance ) {

				return;

			}

			$was_cache_addition_suspended = wp_suspend_cache_addition();

			if ( $this->is_preview() && ! $was_cache_addition_suspended ) {

				wp_suspend_cache_addition( true );

			}

			$this->widget( $args, $instance );

			if ( $this->is_preview() ) {

				wp_suspend_cache_addition( $was_cache_addition_suspended );

			}

		}

	}

	/**

	 * Handles changed settings (Do NOT override).

	 *

	 * @since 2.8.0

	 *

	 * @global array $wp_registered_widgets

	 *

	 * @param int $deprecated Not used.

	 */

	public function update_callback( $deprecated = 1 ) {

		global $wp_registered_widgets;

		$all_instances = $this->get_settings();

		// We need to update the data

		if ( $this->updated )

			return;

		if ( isset($_POST['delete_widget']) && $_POST['delete_widget'] ) {

			// Delete the settings for this instance of the widget

			if ( isset($_POST['the-widget-id']) )

				$del_id = $_POST['the-widget-id'];

			else

				return;

			if ( isset($wp_registered_widgets[$del_id]['params'][0]['number']) ) {

				$number = $wp_registered_widgets[$del_id]['params'][0]['number'];

				if ( $this->id_base . '-' . $number == $del_id )

					unset($all_instances[$number]);

			}

		} else {

			if ( isset($_POST['widget-' . $this->id_base]) && is_array($_POST['widget-' . $this->id_base]) ) {

				$settings = $_POST['widget-' . $this->id_base];

			} elseif ( isset($_POST['id_base']) && $_POST['id_base'] == $this->id_base ) {

				$num = $_POST['multi_number'] ? (int) $_POST['multi_number'] : (int) $_POST['widget_number'];

				$settings = array( $num => array() );

			} else {

				return;

			}

			foreach ( $settings as $number => $new_instance ) {

				$new_instance = stripslashes_deep($new_instance);

				$this->_set($number);

				$old_instance = isset($all_instances[$number]) ? $all_instances[$number] : array();

				$was_cache_addition_suspended = wp_suspend_cache_addition();

				if ( $this->is_preview() && ! $was_cache_addition_suspended ) {

					wp_suspend_cache_addition( true );

				}

				$instance = $this->update( $new_instance, $old_instance );

				if ( $this->is_preview() ) {

					wp_suspend_cache_addition( $was_cache_addition_suspended );

				}

				/**

				 * Filters a widget's settings before saving.

				 *

				 * Returning false will effectively short-circuit the widget's ability

				 * to update settings.

				 *

				 * @since 2.8.0

				 *

				 * @param array     $instance     The current widget instance's settings.

				 * @param array     $new_instance Array of new widget settings.

				 * @param array     $old_instance Array of old widget settings.