#ifndef _MSC_VER //linux
#include <sys/types.h>
#include <sys/stat.h>

#include <unistd.h>
#include <errno.h>
#include <termios.h>
#include <fcntl.h>
#endif

#include "StdAfx.h"
#include "Serial.h"

#include <stdexcept>
#include <string>
#include <sstream>
#include <iostream>
#include <iomanip>

#define _POSIX_SOURCE 1 /* POSIX compliant source */
#define BAUDRATE B9600

#ifndef _MSC_VER // ugly hack, else will gcc not accept this constant in openLinux()
const int flags = O_RDWR | O_NOCTTY ; //| O_NONBLOCK;
#endif

std::string writeLastError()
{
#ifdef _MSC_VER
	LPVOID lpMsgBuf;
	FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER|FORMAT_MESSAGE_FROM_SYSTEM|FORMAT_MESSAGE_IGNORE_INSERTS,
			NULL,
			GetLastError(),
			MAKELANGID(LANG_NEUTRAL,SUBLANG_DEFAULT),
			(LPSTR) &lpMsgBuf,
			0,
			NULL);

	std::ostringstream out;
	out << "Error" << lpMsgBuf;
	return out.str();
#else //linux
	return std::string( strerror(errno) );
#endif
}


CSerial::CSerial()
{
	mIsopen = false;
}

CSerial::CSerial(char* port, int bitrate)
{
	mPortstr = port;
	mBitrate = bitrate;
	mIsopen = false;

#ifdef _MSC_VER
	openWindows();
#else
	openLinux();
#endif
}

CSerial::~CSerial(void)
{
	close();
}

void CSerial::open(char* port, int bitrate)
{
	if (mIsopen)
		throw std::runtime_error("Port already opened");

	mPortstr = port;
	mBitrate = bitrate;
	
#ifdef _MSC_VER
	openWindows();
#else
	openLinux();
#endif
}

#ifdef _MSC_VER
void CSerial::openWindows()
{
	mComport = CreateFile( mPortstr, GENERIC_READ|GENERIC_WRITE,0,0,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,0);

	if (mComport == INVALID_HANDLE_VALUE)
	{
		throw std::runtime_error(writeLastError().c_str());
	}

	DCB dcb;
	dcb.DCBlength = sizeof(DCB);
	mDcbRestore.DCBlength = sizeof(DCB);

	if (!GetCommState(mComport,&dcb) || !GetCommState(mComport,&mDcbRestore))
	{
		std::string error = writeLastError();
		CloseHandle(mComport);
		throw std::exception(error.c_str());
	}

	dcb.BaudRate = mBitrate;
	dcb.ByteSize = 8;
	dcb.Parity = NOPARITY;
	dcb.StopBits = ONESTOPBIT;
	dcb.fDtrControl = DTR_CONTROL_DISABLE;
	dcb.fRtsControl = RTS_CONTROL_DISABLE;
	dcb.fParity = false;
	dcb.fDsrSensitivity = false;

	if (!SetCommState(mComport,&dcb))
	{
		std::string error = writeLastError();
		CloseHandle(mComport);
		throw std::runtime_error( error );
	}

	mIsopen = true;
}
#endif


#ifndef _MSC_VER
void CSerial::openLinux()
{
	termios newtio;

	std::cout << "opening port " << std::endl;	
	mFiledescriptor = ::open(mPortstr, flags);
	if (mFiledescriptor < 0)
		throw std::runtime_error( writeLastError() );

	std::cout << "port opened" << std::endl;
	bzero(&newtio, sizeof(newtio) ); 

	// use a std. 8N1 config
        newtio.c_cflag = BAUDRATE | CRTSCTS | CS8 | CLOCAL | CREAD;
        newtio.c_iflag = IGNPAR;
        newtio.c_oflag = 0;

        /* set input mode (non-canonical, no echo,...) */
        newtio.c_lflag = 0;
		         
        newtio.c_cc[VTIME]    = 0;   /* inter-character timer unused */
        newtio.c_cc[VMIN]     = 0;   /* blocking read until 1 chars received */

	cfmakeraw(&newtio);
	cfsetospeed(&newtio, BAUDRATE);
	
				        
        tcflush(mFiledescriptor, TCIFLUSH);
        tcsetattr(mFiledescriptor, TCSANOW, &newtio);
	
	std::cout << "port configured " << std::endl;
	mIsopen = true;
}
#endif

void CSerial::close()
{
	if (mIsopen)
	{
#ifdef _MSC_VER
		while (getComstat().cbOutQue >0)
			Sleep(5);
		SetCommState(mComport,&mDcbRestore);
		CloseHandle(mComport);
#else // linux close()
		tcdrain(mFiledescriptor);
		tcsetattr(mFiledescriptor, TCSADRAIN, &mOldtio); //restore settings, when all data is written
		::close(mFiledescriptor); //close()== system-call
#endif
		mIsopen = false;
	}
}


int CSerial::readByte()
{
	unsigned char out;
	unsigned long size;

	if (!mIsopen)
		throw std::runtime_error("Port not opened");
#ifdef _MSC_VER
	ReadFile(mComport,&out,1,&size,0);
	if (size != 1)
	{
		std::string error = writeLastError();
		CloseHandle(mComport);
		throw std::exception(error.c_str());
	}
#else //linux readByte()
	size = read(mFiledescriptor, &out, 1);
	if (size != 1) 
	{
		std::cout << writeLastError() << std::endl;
		return -1;
	}
#endif

	printByte("Read", out);
	return out;
}


void CSerial::writeByte(unsigned char out)
{
	unsigned long size;

	printByte("Write", out);
	if (!mIsopen)
		throw std::runtime_error("Port not opened");

#ifdef _MSC_VER
	while (getComstat().cbOutQue >0)
		Sleep(2);

	WriteFile(mComport,&out,1,&size, NULL);
	if (size ==0)
	{
		std::string error = writeLastError();
		CloseHandle(mComport);
		throw std::exception(error.c_str());
	}
#else //linux writeByte()
	//tcdrain(mFiledescriptor);
	size = write(mFiledescriptor,&out,1);
	Sleep(50);
	//tcdrain(mFiledescriptor);
	if (size != 1)
		throw std::runtime_error(writeLastError() );
#endif
}

#ifdef _MSC_VER
COMSTAT CSerial::getComstat() const
{
	if (!mIsopen)
		throw std::exception("Port not opened");

	COMSTAT stat;
	DWORD x;
	ClearCommError(mComport,&x,&stat);
	return stat;
}
#endif

int CSerial::bytesReady() const
{
#ifdef _MSC_VER
	return getComstat().cbInQue;
#else
	return 0;
#endif
}

int CSerial::outQueueSize() const
{
#ifdef _MSC_VER
	return getComstat().cbOutQue;
#else
	return 0;
#endif
}

// Debug function
//
void CSerial::printByte(char* description, unsigned char byte)
{
	std::cout << description << " : " <<  (int) byte << "/" << std::setw(2) << std::setfill('0') << std::hex << (int) byte << std::endl;
	std::cout << std::dec;
}


/*
void CSerial::writeBytes(UCVector out)
{
	unsigned long bytesWritten;
	unsigned int size = out.size();
	unsigned char *buf = new unsigned char[size];

	for (int i=0; i<size; i++)
		buf[i] = out[i];

	WriteFile(mComport,buf,size,&bytesWritten,NULL);
	if (bytesWritten != size)
	{
		std::string error = writeLastError();
		CloseHandle(mComport);
		throw std::exception(error.c_str());
	}
	delete[] buf;
}
*/


/*
UCVector CSerial::readBytes(int maxcount)
{
	UCVector buf;



	return buf;
}
*/