use serial buffer for initialization messages when uploading games (#2062)

fix upload not working - use serial buffer

Co-authored-by: fayd <[email protected]>

Author: recursiveforte

src/lib/upload.ts

@@ -128,13 +128,20 @@ export const getIsLegacySerial = async (
 	await writer.ready
 	await writer.write(new Uint8Array([ 0, 1, 2, 3, 4 ]).buffer)
 
+	// 128-char buffer
+	let serialBuffer = " ".repeat(128)
+
 	while (true) {
 		const { value, done } = await reader.read()
+		
 		if (done) return null
 		logSerialOutput(value)
 
-		if (value.indexOf('found startup seq!') >= 0) return true
-		if (value.indexOf('legacy detected') >= 0) return false
+		serialBuffer  = serialBuffer.concat(value)
+		serialBuffer = serialBuffer.slice(serialBuffer.length - 128, serialBuffer.length)
+
+		if (serialBuffer.indexOf('found startup seq!') >= 0) return true
+		if (serialBuffer.indexOf('legacy detected') >= 0) return false
 	}
 }