/*!
  \file
  \brief シリアル通信の実処理 (Windows)

  \author Satofumi KAMIMURA

  $Id: SerialDevice_win.cpp 1636 2010-01-21 12:50:34Z satofumi $
*/

#include "DetectOS.h"
#include <windows.h>
#include <setupapi.h>
#include <string>
#include <cstdio>

#ifdef MSC
#define snprintf _snprintf
#endif

using namespace std;

#undef min
#undef max


class RawSerialDevice
{
  string error_message_;
  HANDLE hCom_;
  int current_timeout_;
  string com_name_;


public:
  RawSerialDevice(void)
    : error_message_("no error."), hCom_(INVALID_HANDLE_VALUE),
      current_timeout_(0)
  {
  }


  const char* what(void)
  {
    return error_message_.c_str();
  }


  bool connect(const char* device, long baudrate)
  {
    /* COM ポートを開く */
    enum { NameLength = 11 };
    char adjusted_device[NameLength];
    snprintf(adjusted_device, NameLength, "\\\\.\\%s", device);
    hCom_ = CreateFileA(adjusted_device, GENERIC_READ | GENERIC_WRITE, 0,
                        NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);

    if (hCom_ == INVALID_HANDLE_VALUE) {
      error_message_ = string("open failed: ") + device;
      return false;
    }
    com_name_ = device;

    // 通信サイズの更新
    SetupComm(hCom_, 4096 * 8, 4096);

    // タイムアウト設定
    setTimeout(current_timeout_);

    // ボーレートの変更
    bool ret = setBaudrate(baudrate);
    if (! ret) {
      error_message_ = "fail SerialDevice::setBaudrate()";
    }

    return true;
  }


  void setTimeout(int timeout)
  {
    COMMTIMEOUTS timeouts;
    GetCommTimeouts(hCom_, &timeouts);

    timeouts.ReadIntervalTimeout = (timeout == 0) ? MAXDWORD : 0;
    timeouts.ReadTotalTimeoutConstant = timeout;
    timeouts.ReadTotalTimeoutMultiplier = 0;

    SetCommTimeouts(hCom_, &timeouts);
  }



  void disconnect(void)
  {
    if (hCom_ != INVALID_HANDLE_VALUE) {
      CloseHandle(hCom_);
      hCom_ = INVALID_HANDLE_VALUE;
    }
  }


  bool isConnected(void)
  {
    return (hCom_ == INVALID_HANDLE_VALUE) ? false : true;
  }


  bool setBaudrate(long baudrate)
  {
    long baudrate_value;
    switch (baudrate) {

    case 4800:
      baudrate_value = CBR_4800;
      break;

    case 9600:
      baudrate_value = CBR_9600;
      break;

    case 19200:
      baudrate_value = CBR_19200;
      break;

    case 38400:
      baudrate_value = CBR_38400;
      break;

    case 57600:
      baudrate_value = CBR_57600;
      break;

    case 115200:
      baudrate_value = CBR_115200;
      break;

    default:
      baudrate_value = baudrate;
    }

    DCB dcb;
    GetCommState(hCom_, &dcb);
    dcb.BaudRate = baudrate_value;
    dcb.ByteSize = 8;
    dcb.Parity = NOPARITY;
    dcb.fParity = FALSE;
    dcb.StopBits = ONESTOPBIT;
    if (SetCommState(hCom_, &dcb) == 0) {
      flush();
      return false;
    } else {
      return true;
    }
  }


  int send(const char* data, size_t count)
  {
    if (count <= 0) {
      return 0;
    }

    DWORD n;
    WriteFile(hCom_, data, (DWORD)count, &n, NULL);
    return n;
  }


  int receive(char data[], int count, int timeout)
  {
    if (count <= 0) {
      return 0;
    }

    if (timeout != current_timeout_) {
      setTimeout(timeout);
      current_timeout_ = timeout;
    }

    DWORD n;
    ReadFile(hCom_, data, count, &n, NULL);

    return n;
  }


  void flush(void)
  {
    PurgeComm(hCom_,
              PURGE_RXABORT | PURGE_TXABORT | PURGE_RXCLEAR | PURGE_TXCLEAR);
  }
};
