<?php

if ( ! defined( 'ABSPATH' ) ) {
	exit; // disable direct access
}

if ( ! class_exists( 'Mega_Menu_Widget_Manager' ) ) :

	/**
	 * Processes AJAX requests from the Mega Menu panel editor.
	 * Also registers our widget sidebar.
	 *
	 * There is very little in WordPress core to help with listing, editing, saving,
	 * deleting widgets etc so this class implements that functionality.
	 */
	class Mega_Menu_Widget_Manager {

		/**
		 * Constructor
		 *
		 * @since 1.0
		 */
		public function __construct() {

			add_action( 'wp_ajax_mm_edit_widget', array( $this, 'ajax_show_widget_form' ) );
			add_action( 'wp_ajax_mm_edit_menu_item', array( $this, 'ajax_show_menu_item_form' ) );
			add_action( 'wp_ajax_mm_save_widget', array( $this, 'ajax_save_widget' ) );
			add_action( 'wp_ajax_mm_save_menu_item', array( $this, 'ajax_save_menu_item' ) );
			add_action( 'wp_ajax_mm_update_widget_columns', array( $this, 'ajax_update_widget_columns' ) );
			add_action( 'wp_ajax_mm_update_menu_item_columns', array( $this, 'ajax_update_menu_item_columns' ) );
			add_action( 'wp_ajax_mm_delete_widget', array( $this, 'ajax_delete_widget' ) );
			add_action( 'wp_ajax_mm_add_widget', array( $this, 'ajax_add_widget' ) );
			add_action( 'wp_ajax_mm_reorder_items', array( $this, 'ajax_reorder_items' ) );
			add_action( 'wp_ajax_mm_save_grid_data', array( $this, 'ajax_save_grid_data' ) );

			add_filter( 'widget_update_callback', array( $this, 'persist_mega_menu_widget_settings' ), 10, 4 );

			add_action( 'megamenu_after_widget_add', array( $this, 'clear_caches' ) );
			add_action( 'megamenu_after_widget_save', array( $this, 'clear_caches' ) );
			add_action( 'megamenu_after_widget_delete', array( $this, 'clear_caches' ) );

		}


		/**
		 * Depending on how a widget has been written, it may not necessarily base the new widget settings on
		 * a copy the old settings. If this is the case, the mega menu data will be lost. This function
		 * checks to make sure widgets persist the mega menu data when they're saved.
		 *
		 * @since 1.0
		 */
		public function persist_mega_menu_widget_settings( $instance, $new_instance, $old_instance, $that ) {

			if ( isset( $old_instance['mega_menu_columns'] ) && ! isset( $new_instance['mega_menu_columns'] ) ) {
				$instance['mega_menu_columns'] = $old_instance['mega_menu_columns'];
			}

			if ( isset( $old_instance['mega_menu_order'] ) && ! isset( $new_instance['mega_menu_order'] ) ) {
				$instance['mega_menu_order'] = $old_instance['mega_menu_order'];
			}

			if ( isset( $old_instance['mega_menu_parent_menu_id'] ) && ! isset( $new_instance['mega_menu_parent_menu_id'] ) ) {
				$instance['mega_menu_parent_menu_id'] = $old_instance['mega_menu_parent_menu_id'];
			}

			return $instance;
		}


		/**
		 * Display a widget settings form
		 *
		 * @since 1.0
		 */
		public function ajax_show_widget_form() {

			check_ajax_referer( 'megamenu_edit' );

			$capability = apply_filters( 'megamenu_options_capability', 'edit_theme_options' );

			if ( ! current_user_can( $capability ) ) {
				return;
			}

			$widget_id = sanitize_text_field( $_POST['widget_id'] );

			if ( ob_get_contents() ) {
				ob_clean(); // remove any warnings or output from other plugins which may corrupt the response
			}

			wp_die( trim( $this->show_widget_form( $widget_id ) ) );

		}

		/**
		 * Display a menu item settings form
		 *
		 * @since 2.7
		 */
		public function ajax_show_menu_item_form() {

			check_ajax_referer( 'megamenu_edit' );

			$capability = apply_filters( 'megamenu_options_capability', 'edit_theme_options' );

			if ( ! current_user_can( $capability ) ) {
				return;
			}

			$menu_item_id = sanitize_text_field( $_POST['widget_id'] );

			$nonce = wp_create_nonce( 'megamenu_save_menu_item_' . $menu_item_id );

			$saved_settings = array_filter( (array) get_post_meta( $menu_item_id, '_megamenu', true ) );
			$menu_item_meta = array_merge( Mega_Menu_Nav_Menus::get_menu_item_defaults(), $saved_settings );

			if ( ob_get_contents() ) {
				ob_clean(); // remove any warnings or output from other plugins which may corrupt the response
			}
			?>

		<form method='post'>
			<input type='hidden' name='action' value='mm_save_menu_item' />
			<input type='hidden' name='menu_item_id' value='<?php echo esc_attr( $menu_item_id ); ?>' />
			<input type='hidden' name='_wpnonce'  value='<?php echo esc_attr( $nonce ); ?>' />
			<div class='widget-content'>
				<?php

				$css_version = get_transient( 'megamenu_css_version' );

				if ( $css_version && version_compare( $css_version, '2.6.1', '<' ) ) {
					$link    = "<a href='" . esc_attr( admin_url( 'admin.php?page=maxmegamenu_tools' ) ) . "'>" . __( 'Mega Menu' ) . ' > ' . __( 'Tools' ) . '</a>';
					$notice  = "<div class='notice notice-success'><p>";
					$notice .= sprintf( __( 'Your menu CSS needs to be updated before you can use the following setting. Please go to %s and Clear the CSS Cache (you will only need to do this once).', 'megamenu' ), $link );
					$notice .= '</p></div>';
					$notice .= '</div>';

					echo $notice;
				}

				?>

				<p>
					<label><?php _e( 'Sub menu columns', 'megamenu' ); ?></label>

					<select name="settings[submenu_columns]">
						<option value='1' <?php selected( $menu_item_meta['submenu_columns'], 1, true ); ?> >1 <?php __( 'column', 'megamenu' ); ?></option>
						<option value='2' <?php selected( $menu_item_meta['submenu_columns'], 2, true ); ?> >2 <?php __( 'columns', 'megamenu' ); ?></option>
						<option value='3' <?php selected( $menu_item_meta['submenu_columns'], 3, true ); ?> >3 <?php __( 'columns', 'megamenu' ); ?></option>
						<option value='4' <?php selected( $menu_item_meta['submenu_columns'], 4, true ); ?> >4 <?php __( 'columns', 'megamenu' ); ?></option>
						<option value='5' <?php selected( $menu_item_meta['submenu_columns'], 5, true ); ?> >5 <?php __( 'columns', 'megamenu' ); ?></option>
						<option value='6' <?php selected( $menu_item_meta['submenu_columns'], 6, true ); ?> >6 <?php __( 'columns', 'megamenu' ); ?></option>
					</select>
				</p>
				<p>
					<div class='widget-controls'>
						<a class='close' href='#close'><?php _e( 'Close', 'megamenu' ); ?></a>
					</div>

					<?php
						submit_button( __( 'Save' ), 'button-primary alignright', 'savewidget', false );
					?>
				</p>
			</div>
		</form>

			<?php

		}

		/**
		 * Save a menu item
		 *
		 * @since 2.7
		 */
		public function ajax_save_menu_item() {

			$menu_item_id = absint( sanitize_text_field( $_POST['menu_item_id'] ) );

			check_ajax_referer( 'megamenu_save_menu_item_' . $menu_item_id );

			$capability = apply_filters( 'megamenu_options_capability', 'edit_theme_options' );

			if ( ! current_user_can( $capability ) ) {
				return;
			}

			$submitted_settings = isset( $_POST['settings'] ) ? $_POST['settings'] : array();

			if ( $menu_item_id > 0 && is_array( $submitted_settings ) ) {

				$existing_settings = get_post_meta( $menu_item_id, '_megamenu', true );

				if ( is_array( $existing_settings ) ) {
					$submitted_settings = array_merge( $existing_settings, $submitted_settings );
				}

				update_post_meta( $menu_item_id, '_megamenu', $submitted_settings );
			}

			$this->send_json_success( sprintf( __( 'Saved %s', 'megamenu' ), $id_base ) );

		}


		/**
		 * Save a widget
		 *
		 * @since 1.0
		 */
		public function ajax_save_widget() {

			$widget_id = sanitize_text_field( $_POST['widget_id'] );
			$id_base   = sanitize_text_field( $_POST['id_base'] );

			check_ajax_referer( 'megamenu_save_widget_' . $widget_id );

			$capability = apply_filters( 'megamenu_options_capability', 'edit_theme_options' );

			if ( ! current_user_can( $capability ) ) {
				return;
			}

			$saved = $this->save_widget( $id_base );

			if ( $saved ) {
				$this->send_json_success( sprintf( __( 'Saved %s', 'megamenu' ), $id_base ) );
			} else {
				$this->send_json_error( sprintf( __( 'Failed to save %s', 'megamenu' ), $id_base ) );
			}

		}


		/**
		 * Update the number of mega columns for a widget
		 *
		 * @since 1.0
		 */
		public function ajax_update_widget_columns() {

			check_ajax_referer( 'megamenu_edit' );

			$capability = apply_filters( 'megamenu_options_capability', 'edit_theme_options' );

			if ( ! current_user_can( $capability ) ) {
				return;
			}

			$widget_id = sanitize_text_field( $_POST['id'] );
			$columns   = absint( $_POST['columns'] );

			$updated = $this->update_widget_columns( $widget_id, $columns );

			if ( $updated ) {
				$this->send_json_success( sprintf( __( 'Updated %1$s (new columns: %2$d)', 'megamenu' ), $widget_id, $columns ) );
			} else {
				$this->send_json_error( sprintf( __( 'Failed to update %s', 'megamenu' ), $widget_id ) );
			}

		}


		/**
		 * Update the number of mega columns for a widget
		 *
		 * @since 1.0
		 */
		public function ajax_update_menu_item_columns() {

			check_ajax_referer( 'megamenu_edit' );

			$capability = apply_filters( 'megamenu_options_capability', 'edit_theme_options' );

			if ( ! current_user_can( $capability ) ) {
				return;
			}

			$id      = absint( $_POST['id'] );
			$columns = absint( $_POST['columns'] );

			$updated = $this->update_menu_item_columns( $id, $columns );

			if ( $updated ) {
				$this->send_json_success( sprintf( __( 'Updated %1$s (new columns: %2$d)', 'megamenu' ), $id, $columns ) );
			} else {
				$this->send_json_error( sprintf( __( 'Failed to update %s', 'megamenu' ), $id ) );
			}

		}


		/**
		 * Add a widget to the panel
		 *
		 * @since 1.0
		 */
		public function ajax_add_widget() {

			check_ajax_referer( 'megamenu_edit' );

			$capability = apply_filters( 'megamenu_options_capability', 'edit_theme_options' );

			if ( ! current_user_can( $capability ) ) {
				return;
			}

			$id_base        = sanitize_text_field( $_POST['id_base'] );
			$menu_item_id   = absint( $_POST['menu_item_id'] );
			$title          = sanitize_text_field( $_POST['title'] );
			$is_grid_widget = isset( $_POST['is_grid_widget'] ) && $_POST['is_grid_widget'] == 'true';

			$added = $this->add_widget( $id_base, $menu_item_id, $title, $is_grid_widget );

			if ( $added ) {
				$this->send_json_success( $added );
			} else {
				$this->send_json_error( sprintf( __( 'Failed to add %1$s to %2$d', 'megamenu' ), $id_base, $menu_item_id ) );
			}

		}


		/**
		 * Deletes a widget
		 *
		 * @since 1.0
		 */
		public function ajax_delete_widget() {

			check_ajax_referer( 'megamenu_edit' );

			$capability = apply_filters( 'megamenu_options_capability', 'edit_theme_options' );

			if ( ! current_user_can( $capability ) ) {
				return;
			}

			$widget_id = sanitize_text_field( $_POST['widget_id'] );

			$deleted = $this->delete_widget( $widget_id );

			if ( $deleted ) {
				$this->send_json_success( sprintf( __( 'Deleted %s', 'megamenu' ), $widget_id ) );
			} else {
				$this->send_json_error( sprintf( __( 'Failed to delete %s', 'megamenu' ), $widget_id ) );
			}

		}


		/**
		 * Moves a widget to a new position
		 *
		 * @since 1.0
		 */
		public function ajax_reorder_items() {

			check_ajax_referer( 'megamenu_edit' );

			$capability = apply_filters( 'megamenu_options_capability', 'edit_theme_options' );

			if ( ! current_user_can( $capability ) ) {
				return;
			}

			$items = isset( $_POST['items'] ) ? $_POST['items'] : false;

			$saved = false;

			if ( $items ) {
				$moved = $this->reorder_items( $items );
			}

			if ( $moved ) {
				$this->send_json_success( sprintf( __( 'Moved (%s)', 'megamenu' ), json_encode( $items ) ) );
			} else {
				$this->send_json_error( sprintf( __( "Didn't move items", 'megamenu' ), json_encode( $items ) ) );
			}

		}

		/**
		 * Moves a widget to a new position
		 *
		 * @since 2.4
		 */
		public function ajax_save_grid_data() {

			check_ajax_referer( 'megamenu_edit' );

			$capability = apply_filters( 'megamenu_options_capability', 'edit_theme_options' );

			if ( ! current_user_can( $capability ) ) {
				return;
			}

			$grid                = isset( $_POST['grid'] ) ? $_POST['grid'] : false;
			$parent_menu_item_id = absint( $_POST['parent_menu_item'] );

			$saved = true;

			$existing_settings = get_post_meta( $parent_menu_item_id, '_megamenu', true );

			if ( is_array( $grid ) ) {

				$submitted_settings = array_merge( $existing_settings, array( 'grid' => $grid ) );

			}

			update_post_meta( $parent_menu_item_id, '_megamenu', $submitted_settings );

			if ( $saved ) {
				$this->send_json_success( sprintf( __( 'Saved (%s)', 'megamenu' ), json_encode( $grid ) ) );
			} else {
				$this->send_json_error( sprintf( __( "Didn't save", 'megamenu' ), json_encode( $grid ) ) );
			}

		}


		/**
		 * Returns an object representing all widgets registered in WordPress
		 *
		 * @since 1.0
		 */
		public function get_available_widgets() {
			global $wp_widget_factory;

			$widgets = array();

			foreach ( $wp_widget_factory->widgets as $widget ) {

				$disabled_widgets = array( 'maxmegamenu' );

				$disabled_widgets = apply_filters( 'megamenu_incompatible_widgets', $disabled_widgets );

				if ( ! in_array( $widget->id_base, $disabled_widgets ) ) {

					$widgets[] = array(
						'text'  => $widget->name,
						'value' => $widget->id_base,
					);

				}
			}

			uasort( $widgets, array( $this, 'sort_by_text' ) );

			return $widgets;

		}


		/**
		 * Sorts a 2d array by the 'text' key
		 *
		 * @since 1.2
		 * @param array $a
		 * @param array $b
		 */
		function sort_by_text( $a, $b ) {
			return strcmp( $a['text'], $b['text'] );
		}


		/**
		 * Sorts a 2d array by the 'order' key
		 *
		 * @since 2.0
		 * @param array $a
		 * @param array $b
		 */
		function sort_by_order( $a, $b ) {

			if ( $a['order'] == $b['order'] ) {
				return 1;
			}
			return ( $a['order'] < $b['order'] ) ? -1 : 1;

		}


		/**
		 * Returns an array of immediate child menu items for the current item
		 *
		 * @since 1.5
		 * @return array
		 */
		private function get_second_level_menu_items( $parent_menu_item_id, $menu_id, $menu_items = false ) {

			$second_level_items = array();

			// check we're using a valid menu ID
			if ( ! is_nav_menu( $menu_id ) ) {
				return $second_level_items;
			}

			if ( ! $menu_items ) {
				$menu_items = wp_get_nav_menu_items( $menu_id );
			}

			if ( count( $menu_items ) ) {

				foreach ( $menu_items as $item ) {

					// find the child menu items
					if ( $item->menu_item_parent == $parent_menu_item_id ) {

						$saved_settings = array_filter( (array) get_post_meta( $item->ID, '_megamenu', true ) );

						$settings = array_merge( Mega_Menu_Nav_Menus::get_menu_item_defaults(), $saved_settings );

						$second_level_items[ $item->ID ] = array(
							'id'      => $item->ID,
							'type'    => 'menu_item',
							'title'   => $item->title,
							'columns' => $settings['mega_menu_columns'],
							'order'   => isset( $settings['mega_menu_order'][ $parent_menu_item_id ] ) ? $settings['mega_menu_order'][ $parent_menu_item_id ] : 0,
						);

					}
				}
			}

			return $second_level_items;
		}

		/**
		 * Returns an array of all widgets belonging to a specified menu item ID.
		 *
		 * @since 1.0
		 * @param int $menu_item_id
		 */
		public function get_widgets_for_menu_id( $parent_menu_item_id, $menu_id ) {

			$widgets = array();

			if ( $mega_menu_widgets = $this->get_mega_menu_sidebar_widgets() ) {

				foreach ( $mega_menu_widgets as $widget_id ) {

					$settings = $this->get_settings_for_widget_id( $widget_id );

					if ( ! isset( $settings['mega_menu_is_grid_widget'] ) && isset( $settings['mega_menu_parent_menu_id'] ) && $settings['mega_menu_parent_menu_id'] == $parent_menu_item_id ) {

						$name = $this->get_name_for_widget_id( $widget_id );

						$widgets[ $widget_id ] = array(
							'id'      => $widget_id,
							'type'    => 'widget',
							'title'   => $name,
							'columns' => $settings['mega_menu_columns'],
							'order'   => isset( $settings['mega_menu_order'][ $parent_menu_item_id ] ) ? $settings['mega_menu_order'][ $parent_menu_item_id ] : 0,
						);

					}
				}
			}

			return $widgets;

		}


		/**
		 * Returns an array of widgets and second level menu items for a specified parent menu item.
		 * Used to display the widgets/menu items in the mega menu builder.
		 *
		 * @since 2.0
		 * @param int $parent_menu_item_id
		 * @param int $menu_id
		 * @return array
		 */
		public function get_widgets_and_menu_items_for_menu_id( $parent_menu_item_id, $menu_id ) {

			$menu_items = $this->get_second_level_menu_items( $parent_menu_item_id, $menu_id );

			$widgets = $this->get_widgets_for_menu_id( $parent_menu_item_id, $menu_id );

			$items = array_merge( $menu_items, $widgets );

			$parent_settings = get_post_meta( $parent_menu_item_id, '_megamenu', true );

			$ordering = isset( $parent_settings['submenu_ordering'] ) ? $parent_settings['submenu_ordering'] : 'natural';

			if ( $ordering == 'forced' ) {

				uasort( $items, array( $this, 'sort_by_order' ) );

				$new_items = $items;
				$end_items = array();

				foreach ( $items as $key => $value ) {
					if ( $value['order'] == 0 ) {
						unset( $new_items[ $key ] );
						$end_items[] = $value;
					}
				}

				$items = array_merge( $new_items, $end_items );

			}

			return $items;
		}

		/**
		 * Return a sorted array of grid data representing rows, columns and items within each column.
		 *
		 * @param int $parent_menu_item_id
		 * @param int $menu_id
		 * @since 2.4
		 * @return array
		 */
		public function get_grid_widgets_and_menu_items_for_menu_id( $parent_menu_item_id, $menu_id, $menu_items = false ) {

			$meta = get_post_meta( $parent_menu_item_id, '_megamenu', true );

			$saved_grid = array();

			if ( isset( $meta['grid'] ) ) {
				$saved_grid = $this->populate_saved_grid_data( $parent_menu_item_id, $menu_id, $meta['grid'], $menu_items );
			} else {
				// return empty row
				$saved_grid[0]['columns'][0]['meta']['span'] = 3;
				$saved_grid                                  = $this->populate_saved_grid_data( $parent_menu_item_id, $menu_id, $saved_grid, $menu_items );

			}

			return $saved_grid;
		}


		/**
		 * Ensure the widgets that are within the grid data still exist and have not been deleted (through the Widgets screen)
		 * Ensure second level menu items saved within the grid data are still actually second level menu itms within the menu structure
		 *
		 * @param $saved_grid - array representing rows, columns and widgets/menu items within each column
		 * @param $second_level_menu_items - array of second level menu items beneath the current menu item
		 * @since 2.4
		 * @return array
		 */
		public function populate_saved_grid_data( $parent_menu_item_id, $menu_id, $saved_grid, $menu_items ) {

			$second_level_menu_items = $this->get_second_level_menu_items( $parent_menu_item_id, $menu_id, $menu_items );

			$menu_items_included = array();

			foreach ( $saved_grid as $row => $row_data ) {
				if ( isset( $row_data['columns'] ) ) {
					foreach ( $row_data['columns'] as $col => $col_data ) {
						if ( isset( $col_data['items'] ) ) {
							foreach ( $col_data['items'] as $key => $item ) {
								if ( $item['type'] == 'item' ) {
									$menu_items_included[] = $item['id'];
									$is_child_of_parent    = false;

									foreach ( $second_level_menu_items as $menu_item ) {
										if ( $menu_item['id'] == $item['id'] ) {
											$is_child_of_parent = true;
										}
									}

									if ( ! $is_child_of_parent ) {
										unset( $saved_grid[ $row ]['columns'][ $col ]['items'][ $key ] ); // menu item has been deleted or moved
									}
								} else {
									if ( ! $this->get_name_for_widget_id( $item['id'] ) ) {
										unset( $saved_grid[ $row ]['columns'][ $col ]['items'][ $key ] ); // widget no longer exists
									}
								}
							}
						}
					}
				}
			}

			// Find any second level menu items that have been added to the menu but are not yet within the grid data
			$orphaned_items = array();

			foreach ( $second_level_menu_items as $menu_item ) {
				if ( ! in_array( $menu_item['id'], $menu_items_included ) ) {
					$orphaned_items[] = $menu_item;
				}
			}

			if ( ! isset( $saved_grid[0]['columns'][0]['items'][0] ) ) {
				$index = 0; // grid is empty
			} else {
				$index = 999; // create new row
			}

			foreach ( $orphaned_items as $key => $menu_item ) {
				$saved_grid[ $index ]['columns'][0]['meta']['span']  = 3;
				$saved_grid[ $index ]['columns'][0]['items'][ $key ] = array(
					'id'          => $menu_item['id'],
					'type'        => 'item',
					'title'       => $menu_item['title'],
					'description' => __( 'Menu Item', 'megamenu' ),
				);
			}

			if ( is_admin() ) {
				$saved_grid = $this->populate_grid_menu_item_titles( $saved_grid, $menu_id );
			}

			return $saved_grid;
		}


		/**
		 * Loop through the grid data and apply titles and labels to each menu item and widget.
		 *
		 * @param array $saved_grid
		 * @param int $menu_id
		 * @since 2.4
		 * @return array
		 */
		public function populate_grid_menu_item_titles( $saved_grid, $menu_id ) {

			$menu_items = wp_get_nav_menu_items( $menu_id );

			$menu_item_title_map = array();

			foreach ( $menu_items as $item ) {
				$menu_item_title_map[ $item->ID ] = $item->title;
			}

			foreach ( $saved_grid as $row => $row_data ) {
				if ( isset( $row_data['columns'] ) ) {
					foreach ( $row_data['columns'] as $col => $col_data ) {
						if ( isset( $col_data['items'] ) ) {
							foreach ( $col_data['items'] as $key => $item ) {
								if ( $item['type'] == 'item' ) {

									if ( isset( $menu_item_title_map[ $item['id'] ] ) ) {
										$title = $menu_item_title_map[ $item['id'] ];
									} else {
										$title = __( '(no label)' );
									}

									$saved_grid[ $row ]['columns'][ $col ]['items'][ $key ]['title']       = $title;
									$saved_grid[ $row ]['columns'][ $col ]['items'][ $key ]['description'] = __( 'Menu Item', 'megamenu' );
								} else {
									$saved_grid[ $row ]['columns'][ $col ]['items'][ $key ]['title']       = $this->get_title_for_widget_id( $item['id'] );
									$saved_grid[ $row ]['columns'][ $col ]['items'][ $key ]['description'] = $this->get_name_for_widget_id( $item['id'] );
								}
							}
						}
					}
				}
			}

			return $saved_grid;
		}


		/**
		 * Returns the widget data as stored in the options table
		 *
		 * @since 1.8.1
		 * @param string $widget_id
		 */
		public function get_settings_for_widget_id( $widget_id ) {

			$id_base = $this->get_id_base_for_widget_id( $widget_id );

			if ( ! $id_base ) {
				return false;
			}

			$widget_number = $this->get_widget_number_for_widget_id( $widget_id );

			$current_widgets = get_option( 'widget_' . $id_base );

			return $current_widgets[ $widget_number ];

		}

		/**
		 * Returns the widget ID (number)
		 *
		 * @since 1.0
		 * @param string $widget_id - id_base-ID (eg meta-3)
		 * @return int
		 */
		public function get_widget_number_for_widget_id( $widget_id ) {

			$parts = explode( '-', $widget_id );

			return absint( end( $parts ) );

		}

		/**
		 * Returns the name/title of a Widget
		 *
		 * @since 1.0
		 * @param $widget_id - id_base-ID (eg meta-3)
		 * @return string e.g. "Custom HTML" or "Text"
		 */
		public function get_name_for_widget_id( $widget_id ) {
			global $wp_registered_widgets;

			if ( ! isset( $wp_registered_widgets[ $widget_id ] ) ) {
				return false;
			}

			$registered_widget = $wp_registered_widgets[ $widget_id ];

			return $registered_widget['name'];

		}


		/**
		 * Returns the title of a Widget
		 *
		 * @since 2.4
		 * @param $widget_id - id_base-ID (eg meta-3)
		 */
		public function get_title_for_widget_id( $widget_id ) {
			$instance = $this->get_settings_for_widget_id( $widget_id );

			if ( isset( $instance['title'] ) && strlen( $instance['title'] ) ) {
				return $instance['title'];
			}

			return $this->get_name_for_widget_id( $widget_id );

		}

		/**
		 * Returns the id_base value for a Widget ID
		 *
		 * @since 1.0
		 */
		public function get_id_base_for_widget_id( $widget_id ) {
			global $wp_registered_widget_controls;

			if ( ! isset( $wp_registered_widget_controls[ $widget_id ] ) ) {
				return false;
			}

			$control = $wp_registered_widget_controls[ $widget_id ];

			$id_base = isset( $control['id_base'] ) ? $control['id_base'] : $control['id'];

			return $id_base;

		}

		/**
		 * Returns the HTML for a single widget instance.
		 *
		 * @since 1.0
		 * @param string widget_id Something like meta-3
		 */
		public function show_widget( $id ) {
			global $wp_registered_widgets;

			$params = array_merge(
				array(
					array_merge(
						array(
							'widget_id'   => $id,
							'widget_name' => $wp_registered_widgets[ $id ]['name'],
						)
					),
				),
				(array) $wp_registered_widgets[ $id ]['params']
			);

			$params[0]['id']            = 'mega-menu';
			$params[0]['before_title']  = apply_filters( 'megamenu_before_widget_title', '<h4 class="mega-block-title">', $wp_registered_widgets[ $id ] );
			$params[0]['after_title']   = apply_filters( 'megamenu_after_widget_title', '</h4>', $wp_registered_widgets[ $id ] );
			$params[0]['before_widget'] = apply_filters( 'megamenu_before_widget', '', $wp_registered_widgets[ $id ] );
			$params[0]['after_widget']  = apply_filters( 'megamenu_after_widget', '', $wp_registered_widgets[ $id ] );

			if ( defined( 'MEGAMENU_DYNAMIC_SIDEBAR_PARAMS' ) && MEGAMENU_DYNAMIC_SIDEBAR_PARAMS ) {
				$params[0]['before_widget'] = apply_filters( 'megamenu_before_widget', '<div id="" class="">', $wp_registered_widgets[ $id ] );
				$params[0]['after_widget']  = apply_filters( 'megamenu_after_widget', '</div>', $wp_registered_widgets[ $id ] );

				$params = apply_filters( 'dynamic_sidebar_params', $params );
			}

			$callback = $wp_registered_widgets[ $id ]['callback'];

			if ( is_callable( $callback ) ) {
				ob_start();
				call_user_func_array( $callback, $params );
				return ob_get_clean();
			}

		}


		/**
		 * Returns the class name for a widget instance.
		 *
		 * @since 1.8.1
		 * @param string widget_id Something like meta-3
		 */
		public function get_widget_class( $id ) {
			global $wp_registered_widgets;

			if ( isset( $wp_registered_widgets[ $id ]['classname'] ) ) {
				return $wp_registered_widgets[ $id ]['classname'];
			}

			return '';
		}


		/**
		 * Shows the widget edit form for the specified widget.
		 *
		 * @since 1.0
		 * @param $widget_id - id_base-ID (eg meta-3)
		 */
		public function show_widget_form( $widget_id ) {
			global $wp_registered_widget_controls;

			$control = $wp_registered_widget_controls[ $widget_id ];

			$id_base = $this->get_id_base_for_widget_id( $widget_id );

			$widget_number = $this->get_widget_number_for_widget_id( $widget_id );

			$nonce = wp_create_nonce( 'megamenu_save_widget_' . $widget_id );

			?>

		<form method='post'>
			<input type="hidden" name="widget-id" class="widget-id" value="<?php echo esc_attr( $widget_id ); ?>" />
			<input type='hidden' name='action'    value='mm_save_widget' />
			<input type='hidden' name='id_base'   class="id_base" value='<?php echo esc_attr( $id_base ); ?>' />
			<input type='hidden' name='widget_id' value='<?php echo esc_attr( $widget_id ); ?>' />
			<input type='hidden' name='_wpnonce'  value='<?php echo esc_attr( $nonce ); ?>' />
			<div class='widget-content'>
				<?php
				if ( is_callable( $control['callback'] ) ) {
					call_user_func_array( $control['callback'], $control['params'] );
				}
				?>

				<div class='widget-controls'>
					<a class='delete' href='#delete'><?php _e( 'Delete', 'megamenu' ); ?></a> |
					<a class='close' href='#close'><?php _e( 'Close', 'megamenu' ); ?></a>
				</div>

				<?php
					submit_button( __( 'Save' ), 'button-primary alignright', 'savewidget', false );
				?>
			</div>
		</form>
		

			<?php
		}


		/**
		 * Saves a widget. Calls the update callback on the widget.
		 * The callback inspects the post values and updates all widget instances which match the base ID.
		 *
		 * @since 1.0
		 * @param string $id_base - e.g. 'meta'
		 * @return bool
		 */
		public function save_widget( $id_base ) {
			global $wp_registered_widget_updates;

			$control = $wp_registered_widget_updates[ $id_base ];

			if ( is_callable( $control['callback'] ) ) {

				call_user_func_array( $control['callback'], $control['params'] );

				do_action( 'megamenu_after_widget_save' );

				return true;
			}

			return false;

		}


		/**
		 * Adds a widget to WordPress. First creates a new widget instance, then
		 * adds the widget instance to the mega menu widget sidebar area.
		 *
		 * @since 1.0
		 * @param string $id_base
		 * @param int $menu_item_id
		 * @param string $title
		 */
		public function add_widget( $id_base, $menu_item_id, $title, $is_grid_widget ) {

			require_once( ABSPATH . 'wp-admin/includes/widgets.php' );

			$next_id = next_widget_id_number( $id_base );

			$this->add_widget_instance( $id_base, $next_id, $menu_item_id, $is_grid_widget );

			$widget_id = $this->add_widget_to_sidebar( $id_base, $next_id );

			$return  = '<div class="widget" title="' . esc_attr( $title ) . '" data-columns="2" id="' . $widget_id . '" data-type="widget" data-id="' . $widget_id . '">';
			$return .= '    <div class="widget-top">';
			$return .= '        <div class="widget-title-action">';

			if ( ! $is_grid_widget ) {
				$return .= '            <a class="widget-option widget-contract" title="' . esc_attr( __( 'Contract', 'megamenu' ) ) . '"></a>';
				$return .= '            <span class="widget-cols"><span class="widget-num-cols">2</span><span class="widget-of">/</span><span class="widget-total-cols">X</span></span>';
				$return .= '            <a class="widget-option widget-expand" title="' . esc_attr( __( 'Expand', 'megamenu' ) ) . '"></a>';
			}

			$return .= '            <a class="widget-option widget-action" title="' . esc_attr( __( 'Edit', 'megamenu' ) ) . '"></a>';
			$return .= '        </div>';
			$return .= '        <div class="widget-title">';
			$return .= '            <h4>' . esc_html( $title ) . '</h4>';

			if ( $is_grid_widget ) {
				$return .= '            <span class="widget-desc">' . esc_html( $title ) . '</span>';
			}

			$return .= '        </div>';
			$return .= '    </div>';
			$return .= '    <div class="widget-inner widget-inside"></div>';
			$return .= '</div>';

			return $return;

		}


		/**
		 * Adds a new widget instance of the specified base ID to the database.
		 *
		 * @since 1.0
		 * @param string $id_base
		 * @param int $next_id
		 * @param int $menu_item_id
		 */
		private function add_widget_instance( $id_base, $next_id, $menu_item_id, $is_grid_widget ) {

			$current_widgets = get_option( 'widget_' . $id_base );

			$current_widgets[ $next_id ] = array(
				'mega_menu_columns'        => 2,
				'mega_menu_parent_menu_id' => $menu_item_id,
			);

			if ( $is_grid_widget ) {
				$current_widgets[ $next_id ] = array(
					'mega_menu_is_grid_widget' => 'true',
				);
			}

			update_option( 'widget_' . $id_base, $current_widgets );

		}

		/**
		 * Removes a widget instance from the database
		 *
		 * @since 1.0
		 * @param string $widget_id e.g. meta-3
		 * @return bool. True if widget has been deleted.
		 */
		private function remove_widget_instance( $widget_id ) {

			$id_base       = $this->get_id_base_for_widget_id( $widget_id );
			$widget_number = $this->get_widget_number_for_widget_id( $widget_id );

			// add blank widget
			$current_widgets = get_option( 'widget_' . $id_base );

			if ( isset( $current_widgets[ $widget_number ] ) ) {

				unset( $current_widgets[ $widget_number ] );

				update_option( 'widget_' . $id_base, $current_widgets );

				return true;

			}

			return false;

		}


		/**
		 * Updates the number of mega columns for a specified widget.
		 *
		 * @since 1.0
		 * @param string $widget_id
		 * @param int $columns
		 */
		public function update_widget_columns( $widget_id, $columns ) {

			$id_base = $this->get_id_base_for_widget_id( $widget_id );

			$widget_number = $this->get_widget_number_for_widget_id( $widget_id );

			$current_widgets = get_option( 'widget_' . $id_base );

			$current_widgets[ $widget_number ]['mega_menu_columns'] = absint( $columns );

			update_option( 'widget_' . $id_base, $current_widgets );

			do_action( 'megamenu_after_widget_save' );

			return true;

		}


		/**
		 * Updates the number of mega columns for a specified widget.
		 *
		 * @since 1.10
		 * @param string $menu_item_id
		 * @param int $columns
		 */
		public function update_menu_item_columns( $menu_item_id, $columns ) {

			$existing_settings = get_post_meta( $menu_item_id, '_megamenu', true );

			$submitted_settings = array(
				'mega_menu_columns' => absint( $columns ),
			);

			if ( is_array( $existing_settings ) ) {
				$submitted_settings = array_merge( $existing_settings, $submitted_settings );
			}

			update_post_meta( $menu_item_id, '_megamenu', $submitted_settings );

			return true;

		}


		/**
		 * Updates the order of a specified widget.
		 *
		 * @since 1.10
		 * @param string $widget_id
		 * @param int $columns
		 */
		public function update_widget_order( $widget_id, $order, $parent_menu_item_id ) {

			$id_base = $this->get_id_base_for_widget_id( $widget_id );

			$widget_number = $this->get_widget_number_for_widget_id( $widget_id );

			$current_widgets = get_option( 'widget_' . $id_base );

			$current_widgets[ $widget_number ]['mega_menu_order'] = array( $parent_menu_item_id => absint( $order ) );

			update_option( 'widget_' . $id_base, $current_widgets );

			return true;

		}


		/**
		 * Updates the order of a specified menu item.
		 *
		 * @since 1.10
		 * @param string $menu_item_id
		 * @param int $order
		 */
		public function update_menu_item_order( $menu_item_id, $order, $parent_menu_item_id ) {

			$submitted_settings['mega_menu_order'] = array( $parent_menu_item_id => absint( $order ) );

			$existing_settings = get_post_meta( $menu_item_id, '_megamenu', true );

			if ( is_array( $existing_settings ) ) {

				$submitted_settings = array_merge( $existing_settings, $submitted_settings );

			}

			update_post_meta( $menu_item_id, '_megamenu', $submitted_settings );

			return true;

		}


		/**
		 * Deletes a widget from WordPress
		 *
		 * @since 1.0
		 * @param string $widget_id e.g. meta-3
		 */
		public function delete_widget( $widget_id ) {

			$this->remove_widget_from_sidebar( $widget_id );
			$this->remove_widget_instance( $widget_id );

			do_action( 'megamenu_after_widget_delete' );

			return true;

		}


		/**
		 * Moves a widget from one position to another.
		 *
		 * @since 1.10
		 * @param array $items
		 * @return string $widget_id. The widget that has been moved.
		 */
		public function reorder_items( $items ) {

			foreach ( $items as $item ) {

				if ( $item['parent_menu_item'] ) {

					$submitted_settings = array( 'submenu_ordering' => 'forced' );

					$existing_settings = get_post_meta( $item['parent_menu_item'], '_megamenu', true );

					if ( is_array( $existing_settings ) ) {

						$submitted_settings = array_merge( $existing_settings, $submitted_settings );

					}

					update_post_meta( $item['parent_menu_item'], '_megamenu', $submitted_settings );
				}

				if ( $item['type'] == 'widget' ) {

					$this->update_widget_order( $item['id'], $item['order'], $item['parent_menu_item'] );

				}

				if ( $item['type'] == 'menu_item' ) {

					$this->update_menu_item_order( $item['id'], $item['order'], $item['parent_menu_item'] );

				}
			}

			return true;

		}


		/**
		 * Adds a widget to the Mega Menu widget sidebar
		 *
		 * @since 1.0
		 */
		private function add_widget_to_sidebar( $id_base, $next_id ) {

			$widget_id = $id_base . '-' . $next_id;

			$sidebar_widgets = $this->get_mega_menu_sidebar_widgets();

			$sidebar_widgets[] = $widget_id;

			$this->set_mega_menu_sidebar_widgets( $sidebar_widgets );

			do_action( 'megamenu_after_widget_add' );

			return $widget_id;

		}


		/**
		 * Removes a widget from the Mega Menu widget sidebar
		 *
		 * @since 1.0
		 * @return string The widget that was removed
		 */
		private function remove_widget_from_sidebar( $widget_id ) {

			$widgets = $this->get_mega_menu_sidebar_widgets();

			$new_mega_menu_widgets = array();

			foreach ( $widgets as $widget ) {

				if ( $widget != $widget_id ) {
					$new_mega_menu_widgets[] = $widget;
				}
			}

			$this->set_mega_menu_sidebar_widgets( $new_mega_menu_widgets );

			return $widget_id;

		}


		/**
		 * Returns an unfiltered array of all widgets in our sidebar
		 *
		 * @since 1.0
		 * @return array
		 */
		public function get_mega_menu_sidebar_widgets() {

			$sidebar_widgets = wp_get_sidebars_widgets();

			if ( ! isset( $sidebar_widgets['mega-menu'] ) ) {
				return false;
			}

			return $sidebar_widgets['mega-menu'];

		}


		/**
		 * Sets the sidebar widgets
		 *
		 * @since 1.0
		 */
		private function set_mega_menu_sidebar_widgets( $widgets ) {

			$sidebar_widgets = wp_get_sidebars_widgets();

			$sidebar_widgets['mega-menu'] = $widgets;

			wp_set_sidebars_widgets( $sidebar_widgets );

		}


		/**
		 * Clear the cache when the Mega Menu is updated.
		 *
		 * @since 1.0
		 */
		public function clear_caches() {

			// https://wordpress.org/plugins/widget-output-cache/
			if ( function_exists( 'menu_output_cache_bump' ) ) {
				menu_output_cache_bump();
			}

			// https://wordpress.org/plugins/widget-output-cache/
			if ( function_exists( 'widget_output_cache_bump' ) ) {
				widget_output_cache_bump();
			}

		}


		/**
		 * Send JSON response.
		 *
		 * Remove any warnings or output from other plugins which may corrupt the response
		 *
		 * @param string $json
		 * @since 1.8
		 */
		public function send_json_success( $json ) {
			if ( ob_get_contents() ) {
				ob_clean();
			}

			wp_send_json_success( $json );
		}


		/**
		 * Send JSON response.
		 *
		 * Remove any warnings or output from other plugins which may corrupt the response
		 *
		 * @param string $json
		 * @since 1.8
		 */
		public function send_json_error( $json ) {
			if ( ob_get_contents() ) {
				ob_clean();
			}

			wp_send_json_error( $json );
		}

	}

endif;
