Add export files feature to DevTools extension

devtools/background.js

@@ -3,26 +3,41 @@
 // Map tab IDs to connections
 const connections = new Map();
 
+// Handshake: Track tabs waiting for content script readiness
+const pendingMessages = new Map();
+
 // Listen for connections from the devtools panel
-chrome.runtime.onConnect.addListener( port => {
+chrome.runtime.onConnect.addListener( ( port ) => {
 
 	let tabId;
 
 	// Listen for messages from the devtools panel
-	port.onMessage.addListener( message => {
+	port.onMessage.addListener( ( message ) => {
+
+		//console.debug('Background: Received message from panel:', message);
 
 		if ( message.name === 'init' ) {
 
 			tabId = message.tabId;
 			connections.set( tabId, port );
+			console.debug( `Background: Connection initialized for tab ${tabId}` );
 
 		} else if ( message.name === 'request-state' && tabId ) {
 
 			chrome.tabs.sendMessage( tabId, message );
 
+		} else if ( message.name.startsWith( 'export-' ) && tabId ) {
+
+			console.log( 'Background: Received export-scene from panel:', message );
+			console.log( 'Background: Forwarding export-scene message to tab:', message );
+			chrome.tabs.sendMessage( tabId, message );
+
 		} else if ( tabId === undefined ) {
 
-			console.warn( 'Background: Message received from panel before init:', message );
+			console.warn(
+				'Background: Message received from panel before init:',
+				message
+			);
 
 		}
 
@@ -34,22 +49,101 @@ chrome.runtime.onConnect.addListener( port => {
 		if ( tabId ) {
 
 			connections.delete( tabId );
+			console.log( `Background: Connection closed for tab ${tabId}` );
+
+		}
+
+	} );
+
+} );
+
+// Enhanced error handling for port lifecycle
+chrome.runtime.onConnect.addListener( ( port ) => {
+
+	let tabId;
+
+	port.onMessage.addListener( ( message ) => {
+
+		if ( message.name === 'init' ) {
+
+			tabId = message.tabId;
+			connections.set( tabId, port );
+
+		} else if ( tabId === undefined ) {
+
+			console.warn( 'Background: Message received from panel before init:', message );
+
+		}
+
+	} );
+
+	port.onDisconnect.addListener( () => {
+
+		if ( tabId ) {
+
+			connections.delete( tabId );
+			console.log( `Background: Connection closed for tab ${tabId}` );
 
 		}
 
 	} );
 
 } );
 
-// Listen for messages from the content script
+// Ensure runtime context initialization
+chrome.webNavigation.onCommitted.addListener( ( details ) => {
+
+	const { tabId, frameId } = details;
+
+	if ( frameId === 0 ) {
+
+		chrome.action.setBadgeText( { tabId: tabId, text: '' } ).catch( () => {
+			/* Tab might be gone */
+		} );
+
+	}
+
+	const port = connections.get( tabId );
+	if ( port ) {
+
+		port.postMessage( {
+			id: 'three-devtools',
+			name: 'committed',
+			frameId: frameId,
+		} );
+
+	}
+
+} );
+
+
+// Listen for handshake from content script
 chrome.runtime.onMessage.addListener( ( message, sender, sendResponse ) => {
 
+	if ( message.name === 'three-devtools-content-ready' && sender.tab ) {
+
+		const tabId = sender.tab.id;
+		console.log( `[Three.js DevTools] Background received handshake from tab ${tabId}` );
+		if ( pendingMessages.has( tabId ) ) {
+
+			const { message: queuedMessage, retryCount } = pendingMessages.get( tabId );
+			console.log( `Background: Handshake received from tab ${tabId}, retrying message.` );
+			pendingMessages.delete( tabId );
+			// Retry sending the original message
+			sendMessageToTab( tabId, queuedMessage, retryCount );
+
+		}
+
+	}
+
+	//console.debug('Background: Received message from content script:', message);
+
 	if ( message.scheme ) {
 
 		chrome.action.setIcon( {
 			path: {
-				128: `icons/128-${message.scheme}.png`
-			}
+				128: `icons/128-${message.scheme}.png`,
+			},
 		} );
 
 	}
@@ -93,40 +187,87 @@ chrome.runtime.onMessage.addListener( ( message, sender, sendResponse ) => {
 
 	}
 
-	return false; // Return false to indicate synchronous handling
+	// --- BEGIN: Handle background download requests (for export fallback) ---
+	if ( message.type === 'request-background-download' && message.detail ) {
 
-} );
+		const { filename, dataUrl, blob, binary } = message.detail;
+		let url = dataUrl;
+		let cleanupUrl = false;
 
-// Listen for page navigation events
-chrome.webNavigation.onCommitted.addListener( details => {
+		// If a Blob is provided, create a blob URL
+		if ( ! url && blob ) {
 
-	const { tabId, frameId } = details;
+			try {
 
-	// Clear badge on navigation, only for top-level navigation
-	if ( frameId === 0 ) {
+				const blobObj = new Blob( [ blob ], { type: binary ? 'model/gltf-binary' : 'application/octet-stream' } );
+				url = URL.createObjectURL( blobObj );
+				cleanupUrl = true;
 
-		chrome.action.setBadgeText( { tabId: tabId, text: '' } ).catch( () => { /* Tab might be gone */ } );
+			} catch ( e ) {
 
-	}
+				console.warn( 'Background: Failed to create blob URL for download:', e );
+				sendResponse && sendResponse( { error: e.message } );
+				return false;
 
-	const port = connections.get( tabId );
+			}
 
-	if ( port ) {
+		}
+
+		if ( ! url ) {
+
+			console.warn( 'Background: No dataUrl or blob provided for background download' );
+			sendResponse && sendResponse( { error: 'No dataUrl or blob provided' } );
+			return false;
+
+		}
+
+		chrome.downloads.download( {
+			url: url,
+			filename: filename || ( binary ? 'scene.glb' : 'scene.gltf' ),
+			saveAs: true
+		}, function ( downloadId ) {
+
+			if ( chrome.runtime.lastError ) {
+
+				console.warn( 'Background: Background download failed:', chrome.runtime.lastError );
+				sendResponse && sendResponse( { error: chrome.runtime.lastError.message } );
+
+			} else {
+
+				console.log( 'Background: Background download started with ID:', downloadId );
+				sendResponse && sendResponse( { success: true, downloadId: downloadId } );
+
+			}
+
+			// Clean up blob URL after a short delay
+			if ( cleanupUrl && url ) {
+
+				setTimeout( function () {
+
+					URL.revokeObjectURL( url );
+					console.log( 'Background: Cleaned up object URL for background download' );
+
+				}, 5000 );
+
+			}
 
-		port.postMessage( {
-			id: 'three-devtools',
-			name: 'committed',
-			frameId: frameId
 		} );
 
+		// Keep the message channel open for sendResponse
+		return true;
+
 	}
+	// --- END: Handle background download requests ---
 
-} );
+	return false; // Return false to indicate synchronous handling
 
+} );
 // Clear badge when a tab is closed
 chrome.tabs.onRemoved.addListener( ( tabId ) => {
 
-	chrome.action.setBadgeText( { tabId: tabId, text: '' } ).catch( () => { /* Tab might be gone */ } );
+	chrome.action.setBadgeText( { tabId: tabId, text: '' } ).catch( () => {
+		/* Tab might be gone */
+	} );
 
 	// Clean up connection if it exists for the closed tab
 	if ( connections.has( tabId ) ) {