<?php 
/**
 * Import widget JSON data, props to https://wordpress.org/plugins/widget-importer-exporter/
 *
 */
function kt_wie_import_data( $data ) {

	global $wp_registered_sidebars;

	// Have valid data?
	// If no data or could not decode
	if ( empty( $data ) || ! is_object( $data ) ) {
		wp_die(
			__( 'Import data could not be read. Please try a different file.', 'widget-importer-exporter' ),
			'',
			array( 'back_link' => true )
		);
	}

	// Hook before import
	do_action( 'wie_before_import' );
	$data = apply_filters( 'wie_import_data', $data );

	// Get all available widgets site supports
	$available_widgets = kt_wie_available_widgets();

	// Get all existing widget instances
	$widget_instances = array();
	foreach ( $available_widgets as $widget_data ) {
		$widget_instances[$widget_data['id_base']] = get_option( 'widget_' . $widget_data['id_base'] );
	}

	// Begin results
	$results = array();

	// Loop import data's sidebars
	foreach ( $data as $sidebar_id => $widgets ) {

		// Skip inactive widgets
		// (should not be in export file)
		if ( 'wp_inactive_widgets' == $sidebar_id ) {
			continue;
		}

		// Check if sidebar is available on this site
		// Otherwise add widgets to inactive, and say so
		if ( isset( $wp_registered_sidebars[$sidebar_id] ) ) {
			$sidebar_available = true;
			$use_sidebar_id = $sidebar_id;
			$sidebar_message_type = 'success';
			$sidebar_message = '';
		} else {
			$sidebar_available = false;
			$use_sidebar_id = 'wp_inactive_widgets'; // add to inactive if sidebar does not exist in theme
			$sidebar_message_type = 'error';
			$sidebar_message = __( 'Sidebar does not exist in theme (using Inactive)', 'widget-importer-exporter' );
		}

		// Result for sidebar
		$results[$sidebar_id]['name'] = ! empty( $wp_registered_sidebars[$sidebar_id]['name'] ) ? $wp_registered_sidebars[$sidebar_id]['name'] : $sidebar_id; // sidebar name if theme supports it; otherwise ID
		$results[$sidebar_id]['message_type'] = $sidebar_message_type;
		$results[$sidebar_id]['message'] = $sidebar_message;
		$results[$sidebar_id]['widgets'] = array();

		// Loop widgets
		foreach ( $widgets as $widget_instance_id => $widget ) {

			$fail = false;

			// Get id_base (remove -# from end) and instance ID number
			$id_base = preg_replace( '/-[0-9]+$/', '', $widget_instance_id );
			$instance_id_number = str_replace( $id_base . '-', '', $widget_instance_id );

			// Does site support this widget?
			if ( ! $fail && ! isset( $available_widgets[$id_base] ) ) {
				$fail = true;
				$widget_message_type = 'error';
				$widget_message = __( 'Site does not support widget', 'widget-importer-exporter' ); // explain why widget not imported
			}

			// Filter to modify settings object before conversion to array and import
			// Leave this filter here for backwards compatibility with manipulating objects (before conversion to array below)
			// Ideally the newer wie_widget_settings_array below will be used instead of this
			$widget = apply_filters( 'wie_widget_settings', $widget ); // object

			// Convert multidimensional objects to multidimensional arrays
			// Some plugins like Jetpack Widget Visibility store settings as multidimensional arrays
			// Without this, they are imported as objects and cause fatal error on Widgets page
			// If this creates problems for plugins that do actually intend settings in objects then may need to consider other approach: https://wordpress.org/support/topic/problem-with-array-of-arrays
			// It is probably much more likely that arrays are used than objects, however
			$widget = json_decode( json_encode( $widget ), true );

			// Filter to modify settings array
			// This is preferred over the older wie_widget_settings filter above
			// Do before identical check because changes may make it identical to end result (such as URL replacements)
			$widget = apply_filters( 'wie_widget_settings_array', $widget );

			// Does widget with identical settings already exist in same sidebar?
			if ( ! $fail && isset( $widget_instances[$id_base] ) ) {

				// Get existing widgets in this sidebar
				$sidebars_widgets = get_option( 'sidebars_widgets' );
				$sidebar_widgets = isset( $sidebars_widgets[$use_sidebar_id] ) ? $sidebars_widgets[$use_sidebar_id] : array(); // check Inactive if that's where will go

				// Loop widgets with ID base
				$single_widget_instances = ! empty( $widget_instances[$id_base] ) ? $widget_instances[$id_base] : array();
				foreach ( $single_widget_instances as $check_id => $check_widget ) {

					// Is widget in same sidebar and has identical settings?
					if ( in_array( "$id_base-$check_id", $sidebar_widgets ) && (array) $widget == $check_widget ) {

						$fail = true;
						$widget_message_type = 'warning';
						$widget_message = __( 'Widget already exists', 'widget-importer-exporter' ); // explain why widget not imported

						break;

					}

				}

			}

			// No failure
			if ( ! $fail ) {

				// Add widget instance
				$single_widget_instances = get_option( 'widget_' . $id_base ); // all instances for that widget ID base, get fresh every time
				$single_widget_instances = ! empty( $single_widget_instances ) ? $single_widget_instances : array( '_multiwidget' => 1 ); // start fresh if have to
				$single_widget_instances[] = $widget; // add it

					// Get the key it was given
					end( $single_widget_instances );
					$new_instance_id_number = key( $single_widget_instances );

					// If key is 0, make it 1
					// When 0, an issue can occur where adding a widget causes data from other widget to load, and the widget doesn't stick (reload wipes it)
					if ( '0' === strval( $new_instance_id_number ) ) {
						$new_instance_id_number = 1;
						$single_widget_instances[$new_instance_id_number] = $single_widget_instances[0];
						unset( $single_widget_instances[0] );
					}

					// Move _multiwidget to end of array for uniformity
					if ( isset( $single_widget_instances['_multiwidget'] ) ) {
						$multiwidget = $single_widget_instances['_multiwidget'];
						unset( $single_widget_instances['_multiwidget'] );
						$single_widget_instances['_multiwidget'] = $multiwidget;
					}

					// Update option with new widget
					update_option( 'widget_' . $id_base, $single_widget_instances );

				// Assign widget instance to sidebar
				$sidebars_widgets = get_option( 'sidebars_widgets' ); // which sidebars have which widgets, get fresh every time
				$new_instance_id = $id_base . '-' . $new_instance_id_number; // use ID number from new widget instance
				$sidebars_widgets[$use_sidebar_id][] = $new_instance_id; // add new instance to sidebar
				update_option( 'sidebars_widgets', $sidebars_widgets ); // save the amended data

				// Success message
				if ( $sidebar_available ) {
					$widget_message_type = 'success';
					$widget_message = __( 'Imported', 'widget-importer-exporter' );
				} else {
					$widget_message_type = 'warning';
					$widget_message = __( 'Imported to Inactive', 'widget-importer-exporter' );
				}

			}

			// Result for widget instance
			$results[$sidebar_id]['widgets'][$widget_instance_id]['name'] = isset( $available_widgets[$id_base]['name'] ) ? $available_widgets[$id_base]['name'] : $id_base; // widget name or ID if name not available (not supported by site)
			$results[$sidebar_id]['widgets'][$widget_instance_id]['title'] = ! empty( $widget['title'] ) ? $widget['title'] : __( 'No Title', 'widget-importer-exporter' ); // show "No Title" if widget instance is untitled
			$results[$sidebar_id]['widgets'][$widget_instance_id]['message_type'] = $widget_message_type;
			$results[$sidebar_id]['widgets'][$widget_instance_id]['message'] = $widget_message;

		}

	}

	// Hook after import
	do_action( 'wie_after_import' );

	// Return results
	return apply_filters( 'wie_import_results', $results );

}
function kt_wie_available_widgets() {

	global $wp_registered_widget_controls;

	$widget_controls = $wp_registered_widget_controls;

	$available_widgets = array();

	foreach ( $widget_controls as $widget ) {

		if ( ! empty( $widget['id_base'] ) && ! isset( $available_widgets[$widget['id_base']] ) ) { // no dupes

			$available_widgets[$widget['id_base']]['id_base'] = $widget['id_base'];
			$available_widgets[$widget['id_base']]['name'] = $widget['name'];

		}

	}

	return apply_filters( 'wie_available_widgets', $available_widgets );

}