add theme fonts uris

lib/class-wp-theme-json-resolver-gutenberg.php

@@ -831,6 +831,50 @@ public static function get_style_variations_from_directory( $directory, $scope =
 		return $variations;
 	}
 
+	/**
+	 * Resolves relative paths in theme.json typography to theme absolute paths
+	 * and returns them in an array that can be embedded
+	 * as the value of `_link` object in REST API responses.
+	 *
+	 * @since 6.6.0
+	 *
+	 * @param 
+	 * @return array An array of resolved paths.
+	 */
+	private static function get_resolved_fonts_theme_uris( $theme_json_data ) {
+		$resolved_theme_uris = array();
+
+		if ( !empty( $theme_json_data['settings']['typography']['fontFamilies'] ) ) {
+
+			$font_families = ( $theme_json_data['settings']['typography']['fontFamilies']['theme'] ?? array() )
+				+ ( $theme_json_data['settings']['typography']['fontFamilies']['custom'] ?? array() )
+				+ ( $theme_json_data['settings']['typography']['fontFamilies']['default'] ?? array() );
+
+			foreach ( $font_families as $font_family ) {
+				if ( !empty( $font_family['fontFace'] ) ) {
+					foreach ( $font_family['fontFace'] as $font_face ) {
+						if ( !empty( $font_face['src'] ) ) {
+							$sources = is_string( $font_face['src'] ) 
+								? array( $font_face['src'] )
+								: $font_face['src'];
+							foreach ( $sources as $source ) {
+								if ( str_starts_with( $source, 'file:' ) ) {
+									$resolved_theme_uris[] = array(
+										'name' => $source,
+										'href' => sanitize_url( get_theme_file_uri( str_replace( 'file:./', '', $source ) ) ),
+										'target' => "typography.fontFamilies.{$font_family['slug']}.fontFace.src",
+									);
+								}
+							}
+						}
+					}
+				}
+			}
+		}
+
+		return $resolved_theme_uris;
+	}
+
 
 	/**
 	 * Resolves relative paths in theme.json styles to theme absolute paths
@@ -852,6 +896,12 @@ public static function get_resolved_theme_uris( $theme_json ) {
 
 		$theme_json_data = $theme_json->get_raw_data();
 
+		// Add font URIs.
+		$resolved_theme_uris = array_merge(
+			$resolved_theme_uris,
+			static::get_resolved_fonts_theme_uris( $theme_json_data )
+		);
+
 		// Using the same file convention when registering web fonts. See: WP_Font_Face_Resolver:: to_theme_file_uri.
 		$placeholder = 'file:./';