/**************************************************************
 * 
 * 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.
 * 
 *************************************************************/


#define UNICODE
#define WIN32_LEAN_AND_MEAN
#ifdef _MSC_VER
#pragma warning(push,1) // disable warnings within system headers
#endif
#include <windows.h>
#ifdef _MSC_VER
#pragma warning(pop)
#endif

#define _UNICODE
#include <tchar.h>

#include <string.h>
#include <stdlib.h>
#include <systools/win32/uwinapi.h>

#include <stdio.h>

#ifdef UNOPKG

DWORD passOutputToConsole(HANDLE readPipe, HANDLE console)
{
	BYTE aBuffer[1024];
	DWORD dwRead = 0;
	HANDLE hReadPipe = readPipe;
	BOOL fSuccess;
	DWORD dwWritten;

	//Indicates that we read an odd number of bytes. That is, we only read half of the last
	//wchar_t
	bool bIncompleteWchar = false;
	//fprintf, fwprintf will both send char data without the terminating zero. 
	//fwprintf converts the unicode string first.
	//We expect here to receive unicode without the terminating zero. 
	//unopkg and the extension manager code MUST 
	//use dp_misc::writeConsole instead of using fprintf, etc.
	
	DWORD dwToRead = sizeof(aBuffer);
	BYTE * pBuffer = aBuffer;
	while ( ReadFile( hReadPipe, pBuffer, dwToRead, &dwRead, NULL ) )
	{
		//If the previous ReadFile call read an odd number of bytes, then the last one was
		//put at the front of the buffer. We increase the number of read bytes by one to reflect
		//that one byte.
		if (bIncompleteWchar)
			dwRead++;
		//We must make sure that only complete wchar_t|s are written. WriteConsolse takes
		//the number of wchar_t|s as argument. ReadFile, however, reads bytes.
		bIncompleteWchar = dwRead % 2 ? true : false;
		if (bIncompleteWchar)
		{
			//To test this case, give aBuffer a small odd size, e.g. aBuffer[3]
			//The last byte, which is the incomplete wchar_t (half of it), will not be written.
			fSuccess = WriteConsoleW( console, aBuffer, 
				(dwRead - 1) / 2, &dwWritten, NULL );
			
			//Move the last byte to the front of the buffer, so that it is the start of the 
			//next string
			aBuffer[0] = aBuffer[dwRead - 1];
			
			//Make sure that ReadFile does not overwrite the first byte the next time
			dwToRead = sizeof(aBuffer) - 1;
			pBuffer = aBuffer + 1;
			
		}
		else
		{	//We have read an even number of bytes. Therefore, we do not put the last incomplete
			//wchar_t at the front of the buffer. We will use the complete buffer the next time 
			//when ReadFile is called.
			dwToRead = sizeof(aBuffer);
			pBuffer = aBuffer;
			fSuccess = WriteConsoleW( console, 
				aBuffer, dwRead / 2, &dwWritten, NULL );
		}
	}

	return 0;
}

#endif

#ifdef UNOPKG
DWORD WINAPI OutputThread( LPVOID pParam )
{
	return passOutputToConsole((HANDLE)pParam, GetStdHandle( STD_OUTPUT_HANDLE ));
}

#else
DWORD WINAPI OutputThread( LPVOID pParam )
{
	BYTE	aBuffer[256];
	DWORD	dwRead = 0;
	HANDLE	hReadPipe = (HANDLE)pParam;
	while ( ReadFile( hReadPipe, &aBuffer, sizeof(aBuffer), &dwRead, NULL ) )
	{
		BOOL	fSuccess;
		DWORD	dwWritten;

		fSuccess = WriteFile( GetStdHandle( STD_OUTPUT_HANDLE ), aBuffer, dwRead, &dwWritten, NULL );
	}

	return 0;
}
#endif
//---------------------------------------------------------------------------
// Thread that reads from child process standard error pipe
//---------------------------------------------------------------------------

#ifdef UNOPKG
DWORD WINAPI ErrorThread( LPVOID pParam )
{
	return passOutputToConsole((HANDLE)pParam, GetStdHandle( STD_ERROR_HANDLE ));
}

#else
DWORD WINAPI ErrorThread( LPVOID pParam )
{
	BYTE	aBuffer[256];
	DWORD	dwRead = 0;
	HANDLE	hReadPipe = (HANDLE)pParam;

	while ( ReadFile( hReadPipe, &aBuffer, sizeof(aBuffer), &dwRead, NULL ) )
	{
		BOOL	fSuccess;
		DWORD	dwWritten;

		fSuccess = WriteFile( GetStdHandle( STD_ERROR_HANDLE ), aBuffer, dwRead, &dwWritten, NULL );
	}

	return 0;
}
#endif
//---------------------------------------------------------------------------
// Thread that writes to child process standard input pipe
//---------------------------------------------------------------------------
#ifdef UNOPKG

DWORD WINAPI InputThread( LPVOID pParam )
{
	DWORD	dwRead = 0;
	HANDLE	hWritePipe = (HANDLE)pParam;

    //We need to read in the complete input until we encounter a new line before
    //converting to Unicode. This is necessary because the input string can use
    //characters of one, two, and more bytes. If the last character is not
    //complete, then it will not be converted properly.

    //Find out how a new line (0xd 0xa) looks like with the used code page.
    //Characters may have one or multiple bytes and different byte ordering
    //can be used (little and big endian);
    int cNewLine = WideCharToMultiByte(
        GetConsoleCP(), 0, L"\r\n", 2, NULL, 0, NULL, NULL);
    char * mbBuff = new char[cNewLine];
    WideCharToMultiByte(
        GetConsoleCP(), 0, L"\r\n", 2, mbBuff, cNewLine, NULL, NULL);
    
    const size_t dwBufferSize = 256;
    char* readBuf = (char*) malloc(dwBufferSize);
    int readAll = 0;
    size_t curBufSize = dwBufferSize;
    
    while ( ReadFile( GetStdHandle( STD_INPUT_HANDLE ),
                      readBuf + readAll,
                      curBufSize - readAll, &dwRead, NULL ) )
	{
        readAll += dwRead;
        int lastBufSize = curBufSize;
        //Grow the buffer if necessary
        if (readAll > curBufSize * 0.7)
        {
            curBufSize *= 2;
            readBuf = (char *) realloc(readBuf, curBufSize);
        }
        
        //If the buffer was filled completely then 
        //there could be more input coming. But if we read from the console
        //and the console input fits exactly in the buffer, then the next
        //ReadFile would block until the users presses return, etc.
        //Therefor we check if last character is a new line.
        //To test this, set dwBufferSize to 4 and enter "no". This should produce
        //4 bytes with most code pages.
        if ( readAll == lastBufSize
             && memcmp(readBuf + lastBufSize - cNewLine, mbBuff, cNewLine) != 0)
        {
            //The buffer was completely filled and the last byte(s) are no
            //new line, so there is more to come.
            continue;
        }
        //Obtain the size of the buffer for the converted string.
        int sizeWBuf = MultiByteToWideChar(
            GetConsoleCP(), MB_PRECOMPOSED, readBuf, readAll, NULL, 0);

        wchar_t * wideBuf = new wchar_t[sizeWBuf];

        //Do the conversion.
        MultiByteToWideChar(
            GetConsoleCP(), MB_PRECOMPOSED, readBuf, readAll, wideBuf, sizeWBuf);
        
        BOOL	fSuccess;
		DWORD	dwWritten;
        fSuccess = WriteFile( hWritePipe, wideBuf, sizeWBuf * 2, &dwWritten, NULL );
        delete[] wideBuf;
        readAll = 0;
	}
    delete[] mbBuff;
    free(readBuf);
	return 0;
}
#else
DWORD WINAPI InputThread( LPVOID pParam )
{
	BYTE	aBuffer[256];
	DWORD	dwRead = 0;
	HANDLE	hWritePipe = (HANDLE)pParam;

	while ( ReadFile( GetStdHandle( STD_INPUT_HANDLE ), &aBuffer, sizeof(aBuffer), &dwRead, NULL ) )
	{
		BOOL	fSuccess;
		DWORD	dwWritten;

		fSuccess = WriteFile( hWritePipe, aBuffer, dwRead, &dwWritten, NULL );
	}

	return 0;
}
#endif

//---------------------------------------------------------------------------
// Thread that waits until child process reached input idle
//---------------------------------------------------------------------------

DWORD WINAPI WaitForUIThread( LPVOID pParam )
{
	HANDLE	hProcess = (HANDLE)pParam;

#ifndef UNOPKG
	if ( !_tgetenv( TEXT("UNOPKG") ) )
		WaitForInputIdle( hProcess, INFINITE );
#endif

	return 0;
}


//---------------------------------------------------------------------------
// Ctrl-Break handler that terminates the child process if Ctrl-C was pressed
//---------------------------------------------------------------------------

HANDLE	hTargetProcess = INVALID_HANDLE_VALUE;

BOOL WINAPI CtrlBreakHandler(
  DWORD   //  control signal type
)
{
	TerminateProcess( hTargetProcess, 255 );
	return TRUE;
}


//---------------------------------------------------------------------------

//---------------------------------------------------------------------------

#ifdef __MINGW32__
int main( int, char ** )
#else
int _tmain( int, _TCHAR ** )
#endif
{
	TCHAR				szTargetFileName[MAX_PATH] = TEXT("");
	STARTUPINFO			aStartupInfo;
	PROCESS_INFORMATION	aProcessInfo;

	ZeroMemory( &aStartupInfo, sizeof(aStartupInfo) );
	aStartupInfo.cb = sizeof(aStartupInfo);
	aStartupInfo.dwFlags = STARTF_USESTDHANDLES;

	// Create an output pipe where the write end is inheritable

	HANDLE	hOutputRead, hOutputWrite;
	
	if ( CreatePipe( &hOutputRead, &hOutputWrite, NULL, 0 ) )
	{
		HANDLE	hTemp;

		DuplicateHandle( GetCurrentProcess(), hOutputWrite, GetCurrentProcess(), &hTemp, 0, TRUE, DUPLICATE_SAME_ACCESS );
		CloseHandle( hOutputWrite );
		hOutputWrite = hTemp;

		aStartupInfo.hStdOutput = hOutputWrite;
	}

	// Create an error pipe where the write end is inheritable

	HANDLE	hErrorRead, hErrorWrite;
	
	if ( CreatePipe( &hErrorRead, &hErrorWrite, NULL, 0 ) )
	{
		HANDLE	hTemp;

		DuplicateHandle( GetCurrentProcess(), hErrorWrite, GetCurrentProcess(), &hTemp, 0, TRUE, DUPLICATE_SAME_ACCESS );
		CloseHandle( hErrorWrite );
		hErrorWrite = hTemp;

		aStartupInfo.hStdError = hErrorWrite;
	}

	// Create an input pipe where the read end is inheritable

	HANDLE	hInputRead, hInputWrite;

	if ( CreatePipe( &hInputRead, &hInputWrite, NULL, 0 ) )
	{
		HANDLE	hTemp;

		DuplicateHandle( GetCurrentProcess(), hInputRead, GetCurrentProcess(), &hTemp, 0, TRUE, DUPLICATE_SAME_ACCESS );
		CloseHandle( hInputRead );
		hInputRead = hTemp;

		aStartupInfo.hStdInput = hInputRead;
	}

	// Get image path with same name but with .exe extension

	TCHAR				szModuleFileName[MAX_PATH];

	GetModuleFileName( NULL, szModuleFileName, MAX_PATH );
	_TCHAR	*lpLastDot = _tcsrchr( szModuleFileName, '.' );
	if ( lpLastDot && 0 == _tcsicmp( lpLastDot, _T(".COM") ) )
	{
		size_t len = lpLastDot - szModuleFileName;
		_tcsncpy( szTargetFileName, szModuleFileName, len );
		_tcsncpy( szTargetFileName + len, _T(".EXE"), sizeof(szTargetFileName)/sizeof(szTargetFileName[0]) - len );
	}

	// Create process with same command line, environment and stdio handles which
	// are directed to the created pipes

	BOOL	fSuccess = CreateProcess(
		szTargetFileName,
		GetCommandLine(),
		NULL,
		NULL,
		TRUE,
		0,
		NULL,
		NULL,
		&aStartupInfo,
		&aProcessInfo );

	if ( fSuccess )
	{
		// These pipe ends are inherited by the child process and no longer used
		CloseHandle( hOutputWrite );
		CloseHandle( hErrorWrite );
		CloseHandle( hInputRead );

		// Set the Ctrl-Break handler
		hTargetProcess = aProcessInfo.hProcess;
		SetConsoleCtrlHandler( CtrlBreakHandler, TRUE );

		// Create threads that redirect remote pipe io to current process's console stdio

		DWORD	dwOutputThreadId, dwErrorThreadId, dwInputThreadId;

		HANDLE	hOutputThread = CreateThread( NULL, 0, OutputThread, (LPVOID)hOutputRead, 0, &dwOutputThreadId );
		HANDLE	hErrorThread = CreateThread( NULL, 0, OutputThread, (LPVOID)hErrorRead, 0, &dwErrorThreadId );
		HANDLE	hInputThread = CreateThread( NULL, 0, InputThread, (LPVOID)hInputWrite, 0, &dwInputThreadId );

		// Create thread that wait until child process entered input idle

		DWORD	dwWaitForUIThreadId;
		HANDLE	hWaitForUIThread = CreateThread( NULL, 0, WaitForUIThread, (LPVOID)aProcessInfo.hProcess, 0, &dwWaitForUIThreadId );

		DWORD	dwWaitResult;
		HANDLE	hObjects[] = 
			{
				hTargetProcess,
				hWaitForUIThread,
				hOutputThread,
				hErrorThread
			};

 #ifdef UNOPKG       
        dwWaitResult = WaitForMultipleObjects( elementsof(hObjects), hObjects, TRUE, INFINITE );
 #else        
		bool	bDetach = false;
		int		nOpenPipes = 2;
		do
		{
			dwWaitResult = WaitForMultipleObjects( elementsof(hObjects), hObjects, FALSE, INFINITE );

			switch ( dwWaitResult )
			{
			case WAIT_OBJECT_0:	// The child process has terminated
			case WAIT_OBJECT_0 + 1: // The child process entered input idle
				bDetach = true;
				break;
			case WAIT_OBJECT_0 + 2: // The remote end of stdout pipe was closed
			case WAIT_OBJECT_0 + 3: // The remote end of stderr pipe was closed
				bDetach = --nOpenPipes <= 0;
				break;
			default: // Something went wrong
				bDetach = true;
				break;
			}
		} while( !bDetach );
            
#endif

		CloseHandle( hOutputThread );
		CloseHandle( hErrorThread );
		CloseHandle( hInputThread );
		CloseHandle( hWaitForUIThread );

		DWORD	dwExitCode = 0;
		GetExitCodeProcess( aProcessInfo.hProcess, &dwExitCode );
		CloseHandle( aProcessInfo.hProcess );
		CloseHandle( aProcessInfo.hThread );

		return dwExitCode;
	}

	return -1;
}