Event: Better error message for USB powered devices

device/device.cpp

@@ -270,7 +270,7 @@ APIEvent::Type Device::attemptToBeginCommunication() {
 		// Very unlikely, at the time of writing this only fails if rawWrite does.
 		// If you're looking for this error, you're probably looking for if(!serial) below.
 		// "Communication could not be established with the device. Perhaps it is not powered with 12 volts?"
-		return APIEvent::Type::NoSerialNumber;
+		return getCommunicationNotEstablishedError();
 	}
 
 	auto serial = com->getSerialNumberSync();
@@ -281,7 +281,7 @@ APIEvent::Type Device::attemptToBeginCommunication() {
 			break;
 	}
 	if(!serial) // "Communication could not be established with the device. Perhaps it is not powered with 12 volts?"
-		return APIEvent::Type::NoSerialNumber;
+		return getCommunicationNotEstablishedError();
 	
 	std::string currentSerial = getNeoDevice().serial;
 	if(currentSerial != serial->deviceSerial)
@@ -726,6 +726,32 @@ void Device::handleNeoVIMessage(std::shared_ptr<CANMessage> message) {
 	}
 }
 
+bool Device::firmwareUpdateSupported() {
+	bool ret = false;
+	forEachExtension([&ret](const std::shared_ptr<DeviceExtension>& ext) {
+		if(ext->providesFirmware()) {
+			ret = true;
+			return false;
+		}
+		return true; // false breaks out early
+	});
+	return ret;
+}
+
+APIEvent::Type Device::getCommunicationNotEstablishedError() {
+	if(firmwareUpdateSupported()) {
+		if(requiresVehiclePower())
+			return APIEvent::Type::NoSerialNumberFW12V;
+		else
+			return APIEvent::Type::NoSerialNumberFW;
+	} else {
+		if(requiresVehiclePower())
+			return APIEvent::Type::NoSerialNumber12V;
+		else
+			return APIEvent::Type::NoSerialNumber;
+	}
+}
+
 void Device::updateLEDState() {
 	std::vector<uint8_t> args {(uint8_t) ledState};
 	com->sendCommand(Command::UpdateLEDState, args);