syntax = "proto3";

option java_outer_classname = "GattProto";

package pandora;

import "pandora_experimental/host.proto";
import "google/protobuf/empty.proto";

service GATT {
  // Request an MTU size.
  rpc ExchangeMTU(ExchangeMTURequest) returns (ExchangeMTUResponse);

  // Writes on the given characteristic or descriptor with given handle.
  rpc WriteAttFromHandle(WriteRequest) returns (WriteResponse);

  // Starts service discovery for given uuid.
  rpc DiscoverServiceByUuid(DiscoverServiceByUuidRequest) returns (DiscoverServicesResponse);

  // Starts services discovery.
  rpc DiscoverServices(DiscoverServicesRequest) returns (DiscoverServicesResponse);

  // Starts services discovery using SDP.
  rpc DiscoverServicesSdp(DiscoverServicesSdpRequest) returns (DiscoverServicesSdpResponse);

  // Clears DUT GATT cache.
  rpc ClearCache(ClearCacheRequest) returns (ClearCacheResponse);

  // Reads characteristic with given handle.
  rpc ReadCharacteristicFromHandle(ReadCharacteristicRequest) returns (ReadCharacteristicResponse);

  // Reads characteristic with given uuid, start and end handles.
  rpc ReadCharacteristicsFromUuid(ReadCharacteristicsFromUuidRequest) returns (ReadCharacteristicsFromUuidResponse);

  // Reads characteristic with given descriptor handle.
  rpc ReadCharacteristicDescriptorFromHandle(ReadCharacteristicDescriptorRequest) returns (ReadCharacteristicDescriptorResponse);

  // Register a GATT service
  rpc RegisterService(RegisterServiceRequest) returns (RegisterServiceResponse);
}

enum AttStatusCode {
  SUCCESS = 0x00;
  UNKNOWN_ERROR = 0x101;
  INVALID_HANDLE = 0x01;
  READ_NOT_PERMITTED = 0x02;
  WRITE_NOT_PERMITTED = 0x03;
  INSUFFICIENT_AUTHENTICATION = 0x05;
  INVALID_OFFSET = 0x07;
  ATTRIBUTE_NOT_FOUND = 0x0A;
  INVALID_ATTRIBUTE_LENGTH = 0x0D;
  APPLICATION_ERROR = 0x80;
}

enum AttProperties {
  PROPERTY_NONE = 0x00;
  PROPERTY_READ = 0x02;
  PROPERTY_WRITE = 0x08;
}

enum AttPermissions {
  PERMISSION_NONE = 0x00;
  PERMISSION_READ = 0x01;
  PERMISSION_WRITE = 0x10;
  PERMISSION_READ_ENCRYPTED = 0x02;
}

// A message representing a GATT service.
message GattService {
  uint32 handle = 1;
  uint32 type = 2;
  string uuid = 3;
  repeated GattService included_services = 4;
  repeated GattCharacteristic characteristics = 5;
}

// A message representing a GATT characteristic.
message GattCharacteristic {
  uint32 properties = 1;
  uint32 permissions = 2;
  string uuid = 3;
  uint32 handle = 4;
  repeated GattCharacteristicDescriptor descriptors = 5;
}

// A message representing a GATT descriptors.
message GattCharacteristicDescriptor {
  uint32 handle = 1;
  uint32 permissions = 2;
  string uuid = 3;
}

message AttValue {
  // Descriptor handle or Characteristic handle (not Characteristic Value handle).
  uint32 handle = 1;
  bytes value = 2;
}

// Request for the `ExchangeMTU` rpc.
message ExchangeMTURequest {
  Connection connection = 1;
  int32 mtu = 2;
}

// Response for the `ExchangeMTU` rpc.
message ExchangeMTUResponse {}

// Request for the `WriteAttFromHandle` rpc.
message WriteRequest {
  Connection connection = 1;
  uint32 handle = 2;
  bytes value = 3;
}

// Request for the `WriteAttFromHandle` rpc.
message WriteResponse {
  uint32 handle = 1;
  AttStatusCode status = 2;
}

// Request for the `DiscoverServiceByUuid` rpc.
message DiscoverServiceByUuidRequest {
  Connection connection = 1;
  string uuid = 2;
}

// Request for the `DiscoverServices` rpc.
message DiscoverServicesRequest {
  Connection connection = 1;
}

// Response for the `DiscoverServices` rpc.
message DiscoverServicesResponse {
  repeated GattService services = 1;
}

// Request for the `DiscoverServicesSdp` rpc.
message DiscoverServicesSdpRequest {
  bytes address = 1;
}

// Response for the `DiscoverServicesSdp` rpc.
message DiscoverServicesSdpResponse {
  repeated string service_uuids = 1;
}

// Request for the `ClearCache` rpc.
message ClearCacheRequest {
  Connection connection = 1;
}

// Response for the `ClearCache` rpc.
message ClearCacheResponse {}

// Request for the `ReadCharacteristicFromHandle` rpc.
message ReadCharacteristicRequest {
  Connection connection = 1;
  uint32 handle = 2;
}

// Request for the `ReadCharacteristicsFromUuid` rpc.
message ReadCharacteristicsFromUuidRequest {
  Connection connection = 1;
  string uuid = 2;
  uint32 start_handle = 3;
  uint32 end_handle = 4;
}

// Response for the `ReadCharacteristicFromHandle` rpc.
message ReadCharacteristicResponse {
  AttValue value = 1;
  AttStatusCode status = 2;
}

// Response for the `ReadCharacteristicsFromUuid` rpc.
message ReadCharacteristicsFromUuidResponse {
  repeated ReadCharacteristicResponse characteristics_read = 1;
}

// Request for the `ReadCharacteristicDescriptorFromHandle` rpc.
message ReadCharacteristicDescriptorRequest {
  Connection connection = 1;
  uint32 handle = 2;
}

// Response for the `ReadCharacteristicDescriptorFromHandle` rpc.
message ReadCharacteristicDescriptorResponse {
  AttValue value = 1;
  AttStatusCode status = 2;
}

message GattServiceParams {
  string uuid = 1;
  repeated GattCharacteristicParams characteristics = 2;
}

message GattCharacteristicParams {
  uint32 properties = 1;
  uint32 permissions = 2;
  string uuid = 3;
}

message RegisterServiceRequest {
  GattServiceParams service = 1;
}

message RegisterServiceResponse {
  GattService service = 1;
}