/*
 *
 * Copyright 2015 gRPC authors.
 *
 * 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 <grpc/support/port_platform.h>

#ifdef GPR_WINDOWS_TMPFILE

#include <io.h>
#include <stdio.h>
#include <string.h>
#include <tchar.h>

#include <grpc/support/alloc.h>
#include <grpc/support/log.h>
#include <grpc/support/string_util.h>

#include "src/core/lib/support/string_windows.h"
#include "src/core/lib/support/tmpfile.h"

FILE *gpr_tmpfile(const char *prefix, char **tmp_filename_out) {
  FILE *result = NULL;
  LPTSTR template_string = NULL;
  TCHAR tmp_path[MAX_PATH];
  TCHAR tmp_filename[MAX_PATH];
  DWORD status;
  UINT success;

  if (tmp_filename_out != NULL) *tmp_filename_out = NULL;

  /* Convert our prefix to TCHAR. */
  template_string = gpr_char_to_tchar(prefix);
  GPR_ASSERT(template_string);

  /* Get the path to the best temporary folder available. */
  status = GetTempPath(MAX_PATH, tmp_path);
  if (status == 0 || status > MAX_PATH) goto end;

  /* Generate a unique filename with our template + temporary path. */
  success = GetTempFileName(tmp_path, template_string, 0, tmp_filename);
  if (!success) goto end;

  /* Open a file there. */
  if (_tfopen_s(&result, tmp_filename, TEXT("wb+")) != 0) goto end;

end:
  if (result && tmp_filename_out) {
    *tmp_filename_out = gpr_tchar_to_char(tmp_filename);
  }

  gpr_free(template_string);
  return result;
}

#endif /* GPR_WINDOWS_TMPFILE */
