private static async Task SendEventMessageAsync(GattDeviceService service, CategoryIdType categoryId, ushort eventType)
{
Debug.WriteLine($"Sending message protocol event: '{categoryId}, {eventType}'");
byte[] eventMessage = MessageProtocolFactory.CreateEventMessage(categoryId, eventType);
await BluetoothLeHelper.WriteAsync(eventMessage, service, MessageProtocolRxCharacteristicId);
}
internal RequestBase(CategoryIdType categoryId, ushort requestType, uint sequenceId, byte[] payload, int expectedPayloadLength)
{
if (payload == null && expectedPayloadLength != 0)
{
throw new ArgumentNullException(nameof(payload), "Payload should not be null.");
}
if (payload != null && payload.Length != expectedPayloadLength)
{
throw new ArgumentOutOfRangeException(nameof(payload), $"Payload should be {expectedPayloadLength} bytes. It is {payload.Length}.");
}
CategoryId = categoryId;
RequestType = requestType;
SequenceId = sequenceId;
}
private static RequestBase ExtractRequestPayload(CategoryIdType categoryId, ushort requestType, uint sequenceId, byte[] payload)
{
switch (categoryId)
{
case CategoryIdType.DeviceControl:
DeviceControlRequestId deviceControlRequestId = (DeviceControlRequestId)requestType;
switch (deviceControlRequestId)
{
case DeviceControlRequestId.GetDesiredLedStatus:
return(new DeviceControlGetDesiredLedStatusRequest(deviceControlRequestId, sequenceId));
case DeviceControlRequestId.ReportLedStatus:
return(new DeviceControlReportLedStatusRequest(deviceControlRequestId, sequenceId, payload));
default:
throw new InvalidOperationException($"Unknown response payload type: {(WifiRequestId)requestType}");
}
case CategoryIdType.WifiControl:
WifiRequestId wifiRequestId = (WifiRequestId)requestType;
switch (wifiRequestId)
{
case WifiRequestId.SetWifiStatus:
return(new WifiStatusRequest(wifiRequestId, sequenceId, payload));
case WifiRequestId.SetWifiScanResultsSummary:
return(new WifiScanSummaryRequest(wifiRequestId, sequenceId, payload));
case WifiRequestId.SetNextWifiScanResult:
return(new WifiScanResultRequest(wifiRequestId, sequenceId, payload));
case WifiRequestId.GetNewWifiDetails:
// This request doesn't have a payload
return(new WifiGetNewDetailsRequest(wifiRequestId, sequenceId));
case WifiRequestId.SetWifiOperationResult:
return(new WifiSetRequest(wifiRequestId, sequenceId, payload));
default:
throw new InvalidOperationException($"Unknown response payload type: {wifiRequestId}");
}
default:
throw new InvalidOperationException($"Unknown Category ID type: {categoryId}");
}
}
public static byte[] CreateResponseMessage(CategoryIdType categoryId, ushort requestType, uint sequenceId, byte errorCode, ResponseBase response = null)
{
// Handle response object if provided...
byte[] payload = new byte[0];
if (response != null)
{
payload = response.GetPayload();
}
/* Response format:
*
* | Offset Bytes | 0 | 1 | 2 | 3 |
* | 0 | Preamble |
* | 4 | Length | Msg Type | Reserved |
* | 8 | Category ID | Request ID |
* | 12 | Sequence Number | Result | Reserved |
* | 16 | <Response Data> |
* | ... | ... |
*
* Length : UINT16 (LSB) - the message length excluding the first 6 bytes.
*
* Sequence number : UINT16 (LSB) - must be the same as the sequence number of the
* request this is answering.
*
* Result : 0x00 if successful, > 0x00 as an error code if failed
*/
byte[] message = new byte[16 + payload.Length];
ByteArrayHelper.WriteBytes(Preamble, message);
ByteArrayHelper.WriteLsbUInt16((ushort)(10 + payload.Length), message, 4);
message[6] = (byte)MessageType.Response;
ByteArrayHelper.WriteLsbUInt16((ushort)categoryId, message, 8);
ByteArrayHelper.WriteLsbUInt16(requestType, message, 10);
ByteArrayHelper.WriteLsbUInt16((ushort)sequenceId, message, 12);
message[14] = errorCode;
ByteArrayHelper.WriteBytes(payload, message, 16);
return(message);
}
public static byte[] CreateEventMessage(CategoryIdType categoryId, ushort wifiEventType)
{
/* Event format:
*
* | Offset Bytes | 0 | 1 | 2 | 3 |
* | 0 | Preamble |
* | 4 | Length | Msg Type | Reserved |
* | 8 | Category ID | Event ID |
*
* Length : UINT16 (LSB) - the message length excluding the first 6 bytes.
*/
byte[] message = new byte[12];
ByteArrayHelper.WriteBytes(Preamble, message);
ByteArrayHelper.WriteLsbUInt16(6, message, 4); // Length
message[6] = (byte)MessageType.Event;
ByteArrayHelper.WriteLsbUInt16((ushort)categoryId, message, 8);
ByteArrayHelper.WriteLsbUInt16((ushort)wifiEventType, message, 10);
return(message);
}
public static RequestBase ReadRequestMessagePayload(byte[] message)
{
if (message.Length < 16)
{
throw new ArgumentOutOfRangeException(nameof(message), $"Message should be at least 16 bytes, not {message.Length}.");
}
/* Request format:
*
* | Offset Bytes | 0 | 1 | 2 | 3 |
* | 0 | Preamble |
* | 4 | Length | Msg Type | Reserved |
* | 8 | Category ID | Request ID |
* | 12 | Sequence Number | Reserved |
* | 16 | <Request Data> |
* | ... | ... |
*
* Length : UINT16 (LSB) - the message length excluding the first 6 bytes.
*
* Sequence number : UINT16 (LSB) - must be used for the response to this request.
*/
uint length = ByteArrayHelper.ReadLsbUInt16(message, 4);
CategoryIdType categoryId = (CategoryIdType)ByteArrayHelper.ReadLsbUInt16(message, 8);
ushort requestType = (ushort)ByteArrayHelper.ReadLsbUInt16(message, 10);
uint sequenceId = ByteArrayHelper.ReadLsbUInt16(message, 12);
byte[] payload = null;
uint payloadLength = length - 10;
if (payloadLength > 0)
{
payload = ByteArrayHelper.ReadBytes(message, 16, payloadLength);
}
return(ExtractRequestPayload(categoryId, requestType, sequenceId, payload));
}
