#include <iostream>
#ifdef DEBUG_MESSAGES
#include <fstream> // debug
#endif
#include <string>
#include <vector>
#include <thread>
#include <chrono>

int
main(int argc, char *argv[]) {

#ifdef DEBUG_MESSAGES
  std::ofstream log("childProgram.log");
#endif

  int returnStatus = 25; // Successful return.

  // Output for read test.
  if (argc == 2) {

    // Write a single line and exit.
    if (std::string(argv[1]) == "write") {
#ifdef DEBUG_MESSAGES
      log << "Command is \"write\".  Returning \"This is a test\""
          << " to stdout and stderr." << std::endl;
#endif
      std::cout << "This ";
      std::cout.flush();

      std::cerr << "is a";

      std::cout << " test";
      std::cout.flush();

      if (!std::cout) {
        returnStatus = 10; // Unsuccessful return.
      }

      goto exit;

    }

    // Exit without writing anything.
    if (std::string(argv[1]) == "quit") {
#ifdef DEBUG_MESSAGES
      log << "Command is \"quit\".  Exiting" << std::endl;
#endif
      goto exit;

    }

    // Wait for standard input to close, and exit.
    if (std::string(argv[1]) == "checkStdinEOF") {

#ifdef DEBUG_MESSAGES
      log << "Command is \"checkStdinEOF\".  Checking that stdin is closed."
          << std::endl;
#endif

      int const BufferSize = 512;

      std::vector<char> readBuffer;
      readBuffer.resize(BufferSize, 0);

      std::cin.read(&(readBuffer[0]), BufferSize);

      if (!std::cin.eof()) {

#ifdef DEBUG_MESSAGES
        log << "stdin was not closed." << std::endl;
#endif
        returnStatus = 10; // Unsuccessful return.

      } else {
#ifdef DEBUG_MESSAGES
        log << "stdin was closed." << std::endl;
#endif
        returnStatus = 15; // Successful return.
      }

      goto exit;

    }

  }

  char ch;
#ifdef DEBUG_MESSAGES
  log << "Received \"";
#endif
  while (std::cin >> ch) {

    // Exit?
    if ('q' == ch) {
#ifdef DEBUG_MESSAGES
      log << (char) ch << "\"" << std::endl;
#endif
      break;

    }

    std::cout << (char) std::toupper(ch);
    std::cout.flush();
#ifdef DEBUG_MESSAGES
    log << (char) ch;
    log.flush();
#endif

  }

 exit:
#ifdef DEBUG_MESSAGES
  log.close();
#endif
  std::this_thread::sleep_for(std::chrono::milliseconds(50));
  return returnStatus;

}