//------------------------------------------------------------------------------
// Copyright (c) 2020-2024 EMQ Technologies Co., Ltd. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//------------------------------------------------------------------------------

syntax = "proto3";

package emqx.exproto.v1;

// The Broker side service. It provides a set of APIs to
// handle a protocol access
service ConnectionAdapter {

  // -- socket layer

  rpc Send(SendBytesRequest) returns (CodeResponse) {};

  rpc Close(CloseSocketRequest) returns (CodeResponse) {};

  // -- protocol layer

  rpc Authenticate(AuthenticateRequest) returns (CodeResponse) {};

  rpc StartTimer(TimerRequest) returns (CodeResponse) {};

  // -- pub/sub layer

  rpc Publish(PublishRequest) returns (CodeResponse) {};

  rpc Subscribe(SubscribeRequest) returns (CodeResponse) {};

  rpc Unsubscribe(UnsubscribeRequest) returns (CodeResponse) {};

  rpc RawPublish(RawPublishRequest) returns (CodeResponse) {};
}

// Deprecated service.
// Please using `ConnectionUnaryHandler` to replace it
service ConnectionHandler {

  // -- socket layer

  rpc OnSocketCreated(stream SocketCreatedRequest) returns (EmptySuccess) {};

  rpc OnSocketClosed(stream SocketClosedRequest) returns (EmptySuccess) {};

  rpc OnReceivedBytes(stream ReceivedBytesRequest) returns (EmptySuccess) {};

  // -- pub/sub layer

  rpc OnTimerTimeout(stream TimerTimeoutRequest) returns (EmptySuccess) {};

  rpc OnReceivedMessages(stream ReceivedMessagesRequest) returns (EmptySuccess) {};
}

// This service is an optimization of `ConnectionHandler`.
// In the initial version, we expected to use streams to improve the efficiency
// of requests. But unfortunately, events between different streams are out of
// order. it causes the `OnSocketCreated` event to may arrive later than `OnReceivedBytes`.
//
// So we added the `ConnectionUnaryHandler` service since v4.3.21/v4.4.10 and forced
// the use of Unary in it to avoid ordering problems.
//
// Recommend using `ConnectionUnaryHandler` to replace `ConnectionHandler`
service ConnectionUnaryHandler {

  // -- socket layer

  rpc OnSocketCreated(SocketCreatedRequest) returns (EmptySuccess) {};

  rpc OnSocketClosed(SocketClosedRequest) returns (EmptySuccess) {};

  rpc OnReceivedBytes(ReceivedBytesRequest) returns (EmptySuccess) {};

  // -- pub/sub layer

  rpc OnTimerTimeout(TimerTimeoutRequest) returns (EmptySuccess) {};

  rpc OnReceivedMessages(ReceivedMessagesRequest) returns (EmptySuccess) {};
}

message EmptySuccess { }

enum ResultCode {

  // Operation successfully
  SUCCESS = 0;

  // Unknown Error
  UNKNOWN = 1;

  // Connection process is not alive
  CONN_PROCESS_NOT_ALIVE = 2;

  // Miss the required parameter
  REQUIRED_PARAMS_MISSED = 3;

  // Params type or values incorrect
  PARAMS_TYPE_ERROR = 4;

  // No permission or Pre-conditions not fulfilled
  PERMISSION_DENY = 5;
}

message CodeResponse {

  ResultCode code = 1;

  // The reason message if result is false
  string message = 2;
}

message SendBytesRequest {

  string conn = 1;

  bytes bytes = 2;
}

message CloseSocketRequest {

  string conn = 1;
}

message AuthenticateRequest {

  string conn = 1;

  ClientInfo clientinfo = 2;

  string password = 3;
}

message TimerRequest {

  string conn = 1;

  TimerType type = 2;

  uint32 interval = 3;
}

enum TimerType {

  KEEPALIVE = 0;
}

message PublishRequest {

  string conn = 1;

  string topic = 2;

  uint32 qos = 3;

  bytes payload = 4;
}

message RawPublishRequest {

  string topic = 1;

  uint32 qos = 2;

  bytes payload = 3;
}

message SubscribeRequest {

  string conn = 1;

  string topic = 2;

  uint32 qos = 3;
}

message UnsubscribeRequest {

  string conn = 1;

  string topic = 2;
}

message SocketCreatedRequest {

  string conn = 1;

  ConnInfo conninfo = 2;
}

message ReceivedBytesRequest {

  string conn = 1;

  bytes bytes = 2;
}

message TimerTimeoutRequest {

  string conn = 1;

  TimerType type = 2;
}

message SocketClosedRequest {

  string conn = 1;

  string reason = 2;
}

message ReceivedMessagesRequest {

  string conn = 1;

  repeated Message messages = 2;
}

//--------------------------------------------------------------------
// Basic data types
//--------------------------------------------------------------------

message ConnInfo {

  SocketType socktype = 1;

  Address peername = 2;

  Address sockname = 3;

  CertificateInfo peercert = 4;
}

enum SocketType {

  TCP = 0;

  SSL = 1;

  UDP = 2;

  DTLS = 3;
}

message Address {

  string host = 1;

  uint32 port = 2;
}

message CertificateInfo {

  string cn = 1;

  string dn = 2;
}

message ClientInfo {

  string proto_name = 1;

  string proto_ver = 2;

  string clientid = 3;

  string username = 4;

  // deprecated since v5.1.0
  // the request value of `mountpoint` will be ignored after v5.1.0
  string mountpoint = 5;
}

message Message {

  string node = 1;

  string id = 2;

  uint32 qos = 3;

  string from = 4;

  string topic = 5;

  bytes  payload = 6;

  uint64 timestamp = 7;
}