/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 */

#ifndef CPP_PACKAGE_EXAMPLE_UTILS_H_
#define CPP_PACKAGE_EXAMPLE_UTILS_H_

#include <string>
#include <fstream>
#include <vector>
#include "mxnet-cpp/MxNetCpp.h"

using namespace mxnet::cpp;

#define TRY \
  try {
#define CATCH \
  } catch(dmlc::Error &err) { \
    LG << "Status: FAIL";\
    LG << "With Error: " << MXGetLastError(); \
    return 1; \
  }

bool isFileExists(const std::string &filename) {
  std::ifstream fhandle(filename.c_str());
  return fhandle.good();
}

bool check_datafiles(const std::vector<std::string> &data_files) {
  for (size_t index=0; index < data_files.size(); index++) {
    if (!(isFileExists(data_files[index]))) {
      LG << "Error: File does not exist: "<< data_files[index];
      return false;
    }
  }
  return true;
}

bool setDataIter(MXDataIter *iter , const std::string &useType,
              const std::vector<std::string> &data_files, int batch_size) {
    if (!check_datafiles(data_files)) {
        return false;
    }

    iter->SetParam("batch_size", batch_size);
    iter->SetParam("shuffle", 1);
    iter->SetParam("flat", 1);

    if (useType ==  "Train") {
      iter->SetParam("image", data_files[0]);
      iter->SetParam("label", data_files[1]);
    } else if (useType == "Label") {
      iter->SetParam("image", data_files[2]);
      iter->SetParam("label", data_files[3]);
    }

    iter->CreateDataIter();
    return true;
}

#endif  // CPP_PACKAGE_EXAMPLE_UTILS_H_