/**
 * Copyright 2020 Huawei Technologies Co., Ltd
 *
 * 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.
 */
#include <grpcpp/grpcpp.h>
#include <iostream>
#include <vector>
#include <string>
#include <fstream>
#include "./ms_service.grpc.pb.h"

using grpc::Channel;
using grpc::ClientContext;
using grpc::Status;
using ms_serving::MSService;
using ms_serving::PredictReply;
using ms_serving::PredictRequest;
using ms_serving::Tensor;
using ms_serving::TensorShape;

class MSClient {
 public:
    explicit MSClient(std::shared_ptr<Channel> channel) : stub_(MSService::NewStub(channel)) {}

    ~MSClient() = default;

    std::string Predict() {
      // Data we are sending to the server.
      PredictRequest request;

      Tensor data;
      TensorShape shape;
      shape.add_dims(4);
      *data.mutable_tensor_shape() = shape;
      data.set_tensor_type(ms_serving::MS_FLOAT32);
      std::vector<float> input_data{1, 2, 3, 4};
      data.set_data(input_data.data(), input_data.size() * sizeof(float));
      *request.add_data() = data;
      *request.add_data() = data;
      std::cout << "intput tensor size is " << request.data_size() << std::endl;
      // Container for the data we expect from the server.
      PredictReply reply;

      // Context for the client. It could be used to convey extra information to
      // the server and/or tweak certain RPC behaviors.
      ClientContext context;

      // The actual RPC.
      Status status = stub_->Predict(&context, request, &reply);
      std::cout << "Compute [1, 2, 3, 4] + [1, 2, 3, 4]" << std::endl;
      std::cout << "Add result is";
      for (size_t i = 0; i < reply.result(0).data().size() / sizeof(float); i++) {
        std::cout << " " << (reinterpret_cast<const float *>(reply.mutable_result(0)->mutable_data()->data()))[i];
      }
      std::cout << std::endl;

      // Act upon its status.
      if (status.ok()) {
        return "RPC OK";
      } else {
        std::cout << status.error_code() << ": " << status.error_message() << std::endl;
        return "RPC failed";
      }
    }

 private:
    std::unique_ptr<MSService::Stub> stub_;
};

int main(int argc, char **argv) {
  // Instantiate the client. It requires a channel, out of which the actual RPCs
  // are created. This channel models a connection to an endpoint specified by
  // the argument "--target=" which is the only expected argument.
  // We indicate that the channel isn't authenticated (use of
  // InsecureChannelCredentials()).
  std::string target_str;
  std::string arg_target_str("--target");
  if (argc > 1) {
    // parse target
    std::string arg_val = argv[1];
    size_t start_pos = arg_val.find(arg_target_str);
    if (start_pos != std::string::npos) {
      start_pos += arg_target_str.size();
      if (arg_val[start_pos] == '=') {
        target_str = arg_val.substr(start_pos + 1);
      } else {
        std::cout << "The only correct argument syntax is --target=" << std::endl;
        return 0;
      }
    } else {
      target_str = "localhost:5500";
    }
  } else {
    target_str = "localhost:5500";
  }
  MSClient client(grpc::CreateChannel(target_str, grpc::InsecureChannelCredentials()));
  std::string reply = client.Predict();
  std::cout << "client received: " << reply << std::endl;

  return 0;
}
