// dib.cpp
#include "stdafx.h"
#include "dib.h"


//   - This helper class was borrowed and modifed from
//     David Kruglinski's book Inside Visual C++.


#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

IMPLEMENT_SERIAL(CDib, CObject, 0);

CDib::CDib()
{
	m_hFile = NULL;
	m_hBitmap = NULL;
	m_hPalette = NULL;
	m_nBmihAlloc = m_nImageAlloc = noAlloc;
	Empty();
}

CDib::CDib(CSize size, int nBitCount)
{
	m_hFile = NULL;
	m_hBitmap = NULL;
	m_hPalette = NULL;
	m_nBmihAlloc = m_nImageAlloc = noAlloc;
	Empty();
	ComputePaletteSize(nBitCount);
	m_lpBMIH = (LPBITMAPINFOHEADER) new 
		char[sizeof(BITMAPINFOHEADER) + sizeof(RGBQUAD) * m_nColorTableEntries];
	m_nBmihAlloc = crtAlloc;
	m_lpBMIH->biSize = sizeof(BITMAPINFOHEADER);
	m_lpBMIH->biWidth = size.cx;
	m_lpBMIH->biHeight = size.cy;
	m_lpBMIH->biPlanes = 1;
	m_lpBMIH->biBitCount = nBitCount;
	m_lpBMIH->biCompression = BI_RGB;
	m_lpBMIH->biSizeImage = 0;
	m_lpBMIH->biXPelsPerMeter = 0;
	m_lpBMIH->biYPelsPerMeter = 0;
	m_lpBMIH->biClrUsed = m_nColorTableEntries;
	m_lpBMIH->biClrImportant = m_nColorTableEntries;
	ComputeMetrics();
	memset(m_lpvColorTable, 0, sizeof(RGBQUAD) * m_nColorTableEntries);
	m_lpImage = NULL;  // no data yet
}

CDib::~CDib()
{
	Empty();
}

CSize CDib::GetDimensions()
{	
	if(m_lpBMIH == NULL) return CSize(0, 0);
	return CSize((int) m_lpBMIH->biWidth, (int) m_lpBMIH->biHeight);
}

BOOL CDib::AttachMapFile(const char* strPathname, BOOL bShare) // for reading
{
	// if we open the same file twice, Windows treats it as 2 separate files
	// doesn't work with rare BMP files where # palette entries > biClrUsed
	HANDLE hFile = ::CreateFile(strPathname, GENERIC_WRITE | GENERIC_READ,
		bShare ? FILE_SHARE_READ : 0,
		NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
	ASSERT(hFile != INVALID_HANDLE_VALUE);
	DWORD dwFileSize = ::GetFileSize(hFile, NULL);
	HANDLE hMap = ::CreateFileMapping(hFile, NULL, PAGE_READWRITE, 0, 0, NULL);
	DWORD dwErr = ::GetLastError();
	if(hMap == NULL) {
		AfxMessageBox("Empty bitmap file");
		return FALSE;
	}
	LPVOID lpvFile = ::MapViewOfFile(hMap, FILE_MAP_WRITE, 0, 0, 0); // map whole file
	ASSERT(lpvFile != NULL);
	if(((LPBITMAPFILEHEADER) lpvFile)->bfType != 0x4d42) {
		AfxMessageBox("Invalid bitmap file");
		DetachMapFile();
		return FALSE;
	}
	AttachMemory((LPBYTE) lpvFile + sizeof(BITMAPFILEHEADER));
	m_lpvFile = lpvFile;
	m_hFile = hFile;
	m_hMap = hMap;
	return TRUE;
}

BOOL CDib::CopyToMapFile(const char* strPathname)
{
	// copies DIB to a new file, releases prior pointers
	// if you previously used CreateSection, the HBITMAP will be NULL (and unusable)
	BITMAPFILEHEADER bmfh;
	bmfh.bfType = 0x4d42;  // 'BM'
	bmfh.bfSize = m_dwSizeImage + sizeof(BITMAPINFOHEADER) +
			sizeof(RGBQUAD) * m_nColorTableEntries + sizeof(BITMAPFILEHEADER);
	// meaning of bfSize open to interpretation
	bmfh.bfReserved1 = bmfh.bfReserved2 = 0;
	bmfh.bfOffBits = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) +
			sizeof(RGBQUAD) * m_nColorTableEntries;	
	HANDLE hFile = ::CreateFile(strPathname, GENERIC_WRITE | GENERIC_READ, 0, NULL,
		CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
	ASSERT(hFile != INVALID_HANDLE_VALUE);
	int nSize =  sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) +
				sizeof(RGBQUAD) * m_nColorTableEntries +  m_dwSizeImage;
	HANDLE hMap = ::CreateFileMapping(hFile, NULL, PAGE_READWRITE, 0, nSize, NULL);
	DWORD dwErr = ::GetLastError();
	ASSERT(hMap != NULL);
	LPVOID lpvFile = ::MapViewOfFile(hMap, FILE_MAP_WRITE, 0, 0, 0); // map whole file
	ASSERT(lpvFile != NULL);
	LPBYTE lpbCurrent = (LPBYTE) lpvFile;
	memcpy(lpbCurrent, &bmfh, sizeof(BITMAPFILEHEADER)); // file header
	lpbCurrent += sizeof(BITMAPFILEHEADER);
	LPBITMAPINFOHEADER lpBMIH = (LPBITMAPINFOHEADER) lpbCurrent;
	memcpy(lpbCurrent, m_lpBMIH,
		sizeof(BITMAPINFOHEADER) + sizeof(RGBQUAD) * m_nColorTableEntries); // info
	lpbCurrent += sizeof(BITMAPINFOHEADER) + sizeof(RGBQUAD) * m_nColorTableEntries;
	memcpy(lpbCurrent, m_lpImage, m_dwSizeImage); // bit image
	DWORD dwSizeImage = m_dwSizeImage;
	Empty();
	m_dwSizeImage = dwSizeImage;
	m_nBmihAlloc = m_nImageAlloc = noAlloc;
	m_lpBMIH = lpBMIH;
	m_lpImage = lpbCurrent;
	m_hFile = hFile;
	m_hMap = hMap;
	m_lpvFile = lpvFile;
	ComputePaletteSize(m_lpBMIH->biBitCount);
	ComputeMetrics();
	MakePalette();
	return TRUE;
}

BOOL CDib::AttachMemory(LPVOID lpvMem, BOOL bMustDelete, HGLOBAL hGlobal)
{
	// assumes contiguous BITMAPINFOHEADER, color table, image
	// color table could be zero length
	Empty();
	m_hGlobal = hGlobal;
	if(bMustDelete == FALSE) {
		m_nBmihAlloc = noAlloc;
	}
	else {
		m_nBmihAlloc = ((hGlobal == NULL) ? crtAlloc : heapAlloc);
	}
	try {
		m_lpBMIH = (LPBITMAPINFOHEADER) lpvMem;
		ComputeMetrics();
		ComputePaletteSize(m_lpBMIH->biBitCount);
		m_lpImage = (LPBYTE) m_lpvColorTable + sizeof(RGBQUAD) * m_nColorTableEntries;
		MakePalette();
	}
	catch(CException* pe) {
		AfxMessageBox("AttachMemory error");
		pe->Delete();
		return FALSE;
	}
	return TRUE;
}

UINT CDib::UsePalette(CDC* pDC, BOOL bBackground /* = FALSE */)
{
	if(m_hPalette == NULL) return 0;
	HDC hdc = pDC->GetSafeHdc();
	::SelectPalette(hdc, m_hPalette, bBackground);
	return ::RealizePalette(hdc);
}

BOOL CDib::Draw(CDC* pDC, CPoint origin, CSize size)
{
	if(m_lpBMIH == NULL) return FALSE;
	if(m_hPalette != NULL) {
		::SelectPalette(pDC->GetSafeHdc(), m_hPalette, TRUE);
	}
	pDC->SetStretchBltMode(COLORONCOLOR);
	::StretchDIBits(pDC->GetSafeHdc(), origin.x, origin.y, size.cx, size.cy,
		0, 0, m_lpBMIH->biWidth, m_lpBMIH->biHeight,
		m_lpImage, (LPBITMAPINFO) m_lpBMIH, DIB_RGB_COLORS, SRCCOPY);
	return TRUE;
}

HBITMAP CDib::CreateSection(CDC* pDC /* = NULL */)
{
	if(m_lpBMIH == NULL) return NULL;
	if(m_lpImage != NULL) return NULL; // can only do this if image doesn't exist
	m_hBitmap = ::CreateDIBSection(pDC->GetSafeHdc(), (LPBITMAPINFO) m_lpBMIH,
		DIB_RGB_COLORS,	(LPVOID*) &m_lpImage, NULL, 0);
	ASSERT(m_lpImage != NULL);
	return m_hBitmap;
}

BOOL CDib::MakePalette()
{
	// makes a logical palette (m_hPalette) from the DIB's color table
	// this palette will be selected and realized prior to drawing the DIB
	if(m_nColorTableEntries == 0) return FALSE;
	if(m_hPalette != NULL) ::DeleteObject(m_hPalette);
	TRACE("CDib::MakePalette -- m_nColorTableEntries = %d\n", m_nColorTableEntries);
	LPLOGPALETTE pLogPal = (LPLOGPALETTE) new char[2 * sizeof(WORD) +
		m_nColorTableEntries * sizeof(PALETTEENTRY)];
	pLogPal->palVersion = 0x300;
	pLogPal->palNumEntries = m_nColorTableEntries;
	LPRGBQUAD pDibQuad = (LPRGBQUAD) m_lpvColorTable;
	for(int i = 0; i < m_nColorTableEntries; i++) {
		pLogPal->palPalEntry[i].peRed = pDibQuad->rgbRed;
		pLogPal->palPalEntry[i].peGreen = pDibQuad->rgbGreen;
		pLogPal->palPalEntry[i].peBlue = pDibQuad->rgbBlue;
		pLogPal->palPalEntry[i].peFlags = 0;
		pDibQuad++;
	}
	m_hPalette = ::CreatePalette(pLogPal);
	delete pLogPal;
	return TRUE;
}	

BOOL CDib::SetSystemPalette(CDC* pDC)
{
	// if the DIB doesn't have a color table, we can use the system's halftone palette
	if(m_nColorTableEntries != 0) return FALSE;
	m_hPalette = ::CreateHalftonePalette(pDC->GetSafeHdc());
	return TRUE;
}

HBITMAP CDib::CreateBitmap(CDC* pDC)
{
    if (m_dwSizeImage == 0) return NULL;
    HBITMAP hBitmap = ::CreateDIBitmap(pDC->GetSafeHdc(), m_lpBMIH,
            CBM_INIT, m_lpImage, (LPBITMAPINFO) m_lpBMIH, DIB_RGB_COLORS);
    ASSERT(hBitmap != NULL);
    return hBitmap;
}

BOOL CDib::Compress(CDC* pDC, BOOL bCompress /* = TRUE */)
{
	// 1. makes GDI bitmap from existing DIB
	// 2. makes a new DIB from GDI bitmap with compression
	// 3. cleans up the original DIB
	// 4. puts the new DIB in the object
	if((m_lpBMIH->biBitCount != 4) && (m_lpBMIH->biBitCount != 8)) return FALSE;
		// compression supported only for 4 bpp and 8 bpp DIBs
	if(m_hBitmap) return FALSE; // can't compress a DIB Section!
	TRACE("Compress: original palette size = %d\n", m_nColorTableEntries); 
	HDC hdc = pDC->GetSafeHdc();
	HPALETTE hOldPalette = ::SelectPalette(hdc, m_hPalette, FALSE);
	HBITMAP hBitmap;  // temporary
	if((hBitmap = CreateBitmap(pDC)) == NULL) return FALSE;
	int nSize = sizeof(BITMAPINFOHEADER) + sizeof(RGBQUAD) * m_nColorTableEntries;
	LPBITMAPINFOHEADER lpBMIH = (LPBITMAPINFOHEADER) new char[nSize];
	memcpy(lpBMIH, m_lpBMIH, nSize);  // new header
	if(bCompress) {
		switch (lpBMIH->biBitCount) {
		case 4:
			lpBMIH->biCompression = BI_RLE4;
			break;