Implement multi-theme system

lib/full-site-editing/block-templates.php

@@ -118,8 +118,8 @@ function _gutenberg_build_template_result_from_file( $template_file, $template_t
 
 	$theme               = wp_get_theme()->get_stylesheet();
 	$template            = new WP_Block_Template();
-	$template->id        = $theme . '//' . $template_file['slug'];
-	$template->theme     = $theme;
+	$template->id        = $template_file['slug'];
+	$template->theme     = array( $theme );
 	$template->content   = file_get_contents( $template_file['path'] );
 	$template->slug      = $template_file['slug'];
 	$template->is_custom = false;
@@ -153,12 +153,10 @@ function _gutenberg_build_template_result_from_post( $post ) {
 		return new WP_Error( 'template_missing_theme', __( 'No theme is defined for this template.', 'gutenberg' ) );
 	}
 
-	$theme = $terms[0]->name;
-
 	$template              = new WP_Block_Template();
 	$template->wp_id       = $post->ID;
-	$template->id          = $theme . '//' . $post->post_name;
-	$template->theme       = $theme;
+	$template->id          = $post->post_name;
+	$template->theme       = array();
 	$template->content     = $post->post_content;
 	$template->slug        = $post->post_name;
 	$template->is_custom   = true;
@@ -167,6 +165,10 @@ function _gutenberg_build_template_result_from_post( $post ) {
 	$template->title       = $post->post_title;
 	$template->status      = $post->post_status;
 
+	foreach ( $terms as $term ) {
+		$template->theme[] = $term->slug;
+	}
+
 	return $template;
 }
 
@@ -192,7 +194,7 @@ function gutenberg_get_block_templates( $query = array(), $template_type = 'wp_t
 		'tax_query'      => array(
 			array(
 				'taxonomy' => 'wp_theme',
-				'field'    => 'name',
+				'field'    => 'slug',
 				'terms'    => wp_get_theme()->get_stylesheet(),
 			),
 		),
@@ -223,7 +225,7 @@ function gutenberg_get_block_templates( $query = array(), $template_type = 'wp_t
 		$template_files = _gutenberg_get_template_files( $template_type );
 		foreach ( $template_files as $template_file ) {
 			$is_custom      = array_search(
-				wp_get_theme()->get_stylesheet() . '//' . $template_file['slug'],
+				$template_file['slug'],
 				array_column( $query_result, 'id' ),
 				true
 			);
@@ -242,27 +244,24 @@ function gutenberg_get_block_templates( $query = array(), $template_type = 'wp_t
 /**
  * Retrieves a single unified template object using its id.
  *
- * @param string $id Template unique identifier (example: theme|slug).
+ * @param string $slug Template unique identifier (example: theme|slug).
  * @param array  $template_type wp_template or wp_template_part.
  *
  * @return WP_Block_Template|null Template.
  */
-function gutenberg_get_block_template( $id, $template_type = 'wp_template' ) {
-	$parts = explode( '//', $id, 2 );
-	if ( count( $parts ) < 2 ) {
-		return null;
-	}
-	list( $theme, $slug ) = $parts;
+function gutenberg_get_block_template( $slug, $template_type = 'wp_template' ) {
+	$theme = wp_get_theme()->get_stylesheet();
 	$wp_query_args        = array(
-		'name'           => $slug,
+		// Can't use 'name' because tax_query won't work.
+		'post_name__in'  => array( $slug ),
 		'post_type'      => $template_type,
 		'post_status'    => array( 'auto-draft', 'draft', 'publish', 'trash' ),
 		'posts_per_page' => 1,
 		'no_found_rows'  => true,
 		'tax_query'      => array(
 			array(
 				'taxonomy' => 'wp_theme',
-				'field'    => 'name',
+				'field'    => 'slug',
 				'terms'    => $theme,
 			),
 		),
@@ -278,11 +277,9 @@ function gutenberg_get_block_template( $id, $template_type = 'wp_template' ) {
 		}
 	}
 
-	if ( wp_get_theme()->get_stylesheet() === $theme ) {
-		$template_file = _gutenberg_get_template_file( $template_type, $slug );
-		if ( null !== $template_file ) {
-			return _gutenberg_build_template_result_from_file( $template_file, $template_type );
-		}
+	$template_file = _gutenberg_get_template_file( $template_type, $slug );
+	if ( null !== $template_file ) {
+		return _gutenberg_build_template_result_from_file( $template_file, $template_type );
 	}
 
 	return null;
@@ -303,18 +300,25 @@ function gutenberg_filter_wp_template_unique_post_slug( $slug, $post_ID, $post_s
 	}
 
 	// Template slugs must be unique within the same theme.
-	$theme = get_the_terms( $post_ID, 'wp_theme' )[0]->slug;
+	$tax_query = array(
+		'relation' => 'OR',
+	);
+	$terms = get_the_terms( $post_ID, 'wp_theme' );
+	foreach ( $terms as $term ) {
+		$tax_query[] = array(
+			'taxonomy' => 'wp_theme',
+			'field'    => 'slug',
+			'terms'    => $term->slug,
+		);
+	}
 
 	$check_query_args = array(
-		'post_name'      => $slug,
+		// Can't use 'name' because tax_query won't work.
+		'post_name__in'  => array( $slug ),
 		'post_type'      => $post_type,
 		'posts_per_page' => 1,
 		'post__not_in'   => $post_ID,
-		'tax_query'      => array(
-			'taxonomy' => 'wp_theme',
-			'field'    => 'name',
-			'terms'    => $theme,
-		),
+		'tax_query'      => $tax_query,
 		'no_found_rows'  => true,
 	);
 	$check_query      = new WP_Query( $check_query_args );
@@ -323,10 +327,10 @@ function gutenberg_filter_wp_template_unique_post_slug( $slug, $post_ID, $post_s
 	if ( count( $posts ) > 0 ) {
 		$suffix = 2;
 		do {
-			$query_args              = $check_query_args;
-			$alt_post_name           = _truncate_post_slug( $slug, 200 - ( strlen( $suffix ) + 1 ) ) . "-$suffix";
-			$query_args['post_name'] = $alt_post_name;
-			$query                   = new WP_Query( $check_query_args );
+			$query_args                     = $check_query_args;
+			$alt_post_name                  = _truncate_post_slug( $slug, 200 - ( strlen( $suffix ) + 1 ) ) . "-$suffix";
+			$query_args['post_name__in'][0] = $alt_post_name;
+			$query                          = new WP_Query( $query_args );
 			$suffix++;
 		} while ( count( $query->get_posts() ) > 0 );
 		$slug = $alt_post_name;

lib/full-site-editing/class-wp-block-template.php

@@ -19,9 +19,9 @@ class WP_Block_Template {
 	public $type;
 
 	/**
-	 * Theme.
+	 * Theme(s).
 	 *
-	 * @var string
+	 * @var array
 	 */
 	public $theme;
 

lib/full-site-editing/switch-theme.php

@@ -0,0 +1,124 @@
+<?php
+/**
+ * Theme switcher.
+ *
+ * @package gutenberg
+ */
+
+class WP_Switch_Theme_Page
+{
+	private $title;
+
+	private $themes;
+
+	private $theme_slugs;
+
+	public function __construct() {
+		add_action( 'init', array( $this, 'init' ) );
+		add_action( 'admin_menu', array( $this, 'menu' ) );
+	}
+
+	public function init() {
+		if ( ! gutenberg_is_fse_theme() ) {
+			return;
+		}
+
+		$this->themes = array();
+		$current = wp_get_theme()->get_stylesheet();
+
+		foreach ( wp_get_themes() as $theme ) {
+			if ( is_readable( $theme->stylesheet_dir . '/block-templates/index.html' ) && $theme->stylesheet !== $current ) {
+				$this->themes[] = $theme;
+				$this->theme_slugs[] = $theme->stylesheet;
+			}
+		}
+
+		$this->title = __( 'Switch Theme', 'gutenberg' );
+	}
+
+	public function callback() {
+		if ( ! gutenberg_is_fse_theme() || ! current_user_can( 'switch_themes' ) ) {
+			return;
+		}
+
+		echo '<div class="wrap">';
+		echo '<h2>' . $this->title . '</h2>';
+		echo '<form method="post" action="">';
+
+		if ( isset( $_POST['switch_theme_2'] ) && in_array( $_POST['switch_theme_2'], $this->theme_slugs ) ) {
+
+			$keep_templates = array();
+			$keep_template_parts = array();
+
+			foreach ( $_POST as $key => $value ) {
+
+				if ( $value && strpos( $key, 'keep_template_' ) === 0 ) {
+					$keep_templates[] = substr( $key, 14 );
+				}
+				if ( $value && strpos( $key, 'keep_template-part_' ) === 0 ) {
+					$keep_template_parts[] = substr( $key, 19 );
+				}
+			}
+
+			foreach ( $keep_templates as $template ) {
+				$template = gutenberg_get_block_template( $template, 'wp_template');
+
+				foreach ( parse_blocks( $template->content ) as $block ) {
+					if ( 'core/template-part' === $block['blockName'] && ! empty( $block['attrs']['slug'] ) && ! in_array( $block['attrs']['slug'], $keep_template_parts ) ) {
+						$keep_template_parts[] = $block['attrs']['slug'];
+					}
+				}
+
+				if ( $template->wp_id ) {
+					wp_set_post_terms( $template->wp_id, esc_sql( $_POST['switch_theme_2'] ), 'wp_theme', true );
+				}
+			}
+
+			foreach ( $keep_template_parts as $template_part ) {
+				$template_part = gutenberg_get_block_template( $template_part, 'wp_template_part');
+
+				if ( $template_part->wp_id ) {
+					wp_set_post_terms( $template_part->wp_id, esc_sql( $_POST['switch_theme_2'] ), 'wp_theme', true );
+				}
+			}
+
+			// Temporary
+			echo '<p>Done. Now activating new theme...</p>';
+
+		} else if ( isset( $_POST['switch_theme'] ) && in_array( $_POST['switch_theme'], $this->theme_slugs ) ) {
+			echo '<p>' . __( 'Next, select which templates and template parts to keep from your current theme.', 'gutenberg' ) . '</p>';
+			echo '<p>' . __( 'Templates:', 'gutenberg' ) . '</p>';
+
+			foreach ( gutenberg_get_block_templates( array(), 'wp_template' ) as $template ) {
+				printf( '<input type="checkbox" id="keep_template_%1$s" name="keep_template_%1$s"><label for="keep_template_%1$s">%2$s</label><br>', $template->id, $template->title );
+			}
+
+			echo '<p>' . __( 'Template Parts:', 'gutenberg' ) . '</p>';
+
+			foreach ( gutenberg_get_block_templates( array(), 'wp_template_part' ) as $template_part ) {
+				printf( '<input type="checkbox" id="keep_template-part_%1$s" name="keep_template-part_%1$s"><label for="keep_template-part_%1$s">%2$s</label><br>', $template_part->id, $template_part->title );
+			}
+
+			printf( '<input type="hidden" name="switch_theme_2" value="%s">', esc_attr( $_POST['switch_theme'] ) );
+
+		} else {
+			echo '<p>' . __( 'First, select another full site editing theme to switch to.', 'gutenberg' ) . '</p>';
+
+			foreach ( $this->themes as $theme ) {
+				printf( '<input type="radio" id="%1$s" name="switch_theme" value="%1$s"><label for="%1$s">%2$s</label><br>', $theme->stylesheet, $theme->name );
+			}
+		}
+
+		submit_button();
+		echo '</form></div>';
+	}
+
+	public function menu() {
+		if ( ! gutenberg_is_fse_theme() ) {
+			return;
+		}
+
+		add_submenu_page( 'themes.php', $this->title, $this->title, 'switch_themes', 'gutenberg_switch_theme', array( $this, 'callback' ) );
+	}
+}
+new WP_Switch_Theme_Page();

lib/load.php

@@ -94,6 +94,7 @@ function gutenberg_is_experiment_enabled( $name ) {
 require __DIR__ . '/full-site-editing/template-loader.php';
 require __DIR__ . '/full-site-editing/edit-site-page.php';
 require __DIR__ . '/full-site-editing/edit-site-export.php';
+require __DIR__ . '/full-site-editing/switch-theme.php';
 
 require __DIR__ . '/blocks.php';
 require __DIR__ . '/client-assets.php';

lib/upgrade.php

@@ -18,14 +18,14 @@
  */
 function _gutenberg_migrate_database() {
 	// The default value used here is the first version before migrations were added.
-	$gutenberg_installed_version = get_option( '_GUTENBERG_VERSION_MIGRATION', '9.7.0' );
+	$gutenberg_installed_version = get_option( 'gutenberg_version_migration', '9.7.0' );
 
 	if ( _GUTENBERG_VERSION_MIGRATION !== $gutenberg_installed_version ) {
 		if ( version_compare( $gutenberg_installed_version, '9.8.0', '<' ) ) {
 			_gutenberg_migrate_remove_fse_drafts();
 		}
 
-		update_option( '_GUTENBERG_VERSION_MIGRATION', _GUTENBERG_VERSION_MIGRATION );
+		update_option( 'gutenberg_version_migration', _GUTENBERG_VERSION_MIGRATION );
 	}
 }
 
@@ -37,7 +37,7 @@ function _gutenberg_migrate_database() {
  */
 function _gutenberg_migrate_remove_fse_drafts() {
 	// Delete auto-draft templates and template parts.
-	$delete_query = new WP_QUERY(
+	$delete_query = new WP_Query(
 		array(
 			'post_status'    => array( 'auto-draft' ),
 			'post_type'      => array( 'wp_template', 'wp_template_part' ),
@@ -49,9 +49,9 @@ function _gutenberg_migrate_remove_fse_drafts() {
 	}
 
 	// Delete _wp_file_based term.
-	$term = get_term_by( 'name', '_wp_file_based', 'wp-theme' );
+	$term = get_term_by( 'name', '_wp_file_based', 'wp_theme' );
 	if ( $term ) {
-		wp_delete_term( $term->term_id, 'wp-theme' );
+		wp_delete_term( $term->term_id, 'wp_theme' );
 	}
 }
 

packages/block-library/src/template-part/block.json

@@ -6,9 +6,6 @@
 		"slug": {
 			"type": "string"
 		},
-		"theme": {
-			"type": "string"
-		},
 		"tagName": {
 			"type": "string",
 			"default": "div"

packages/block-library/src/template-part/edit/index.js

@@ -26,11 +26,11 @@ import TemplatePartPlaceholder from './placeholder';
 import TemplatePartSelection from './selection';
 
 export default function TemplatePartEdit( {
-	attributes: { slug, theme, tagName: TagName = 'div' },
+	attributes: { slug, tagName: TagName = 'div' },
 	setAttributes,
 	clientId,
 } ) {
-	const templatePartId = theme + '//' + slug;
+	const templatePartId = slug;
 
 	// Set the postId block attribute if it did not exist,
 	// but wait until the inner blocks have loaded to allow
@@ -39,11 +39,11 @@ export default function TemplatePartEdit( {
 		( select ) => {
 			const { getBlocks } = select( 'core/block-editor' );
 			const entityRecord =
-				theme && slug
+				slug
 					? select( 'core' ).getEntityRecord(
 							'postType',
 							'wp_template_part',
-							theme + '//' + slug
+							slug
 					  )
 					: null;
 

packages/block-library/src/template-part/edit/placeholder/index.js

@@ -31,7 +31,6 @@ export default function TemplatePartPlaceholder( {
 		);
 		setAttributes( {
 			slug: templatePart.slug,
-			theme: templatePart.theme,
 		} );
 	}, [ setAttributes ] );