#include "pre.h"


PBITMAPINFO CreateBitmapInfoStruct
(
    HBITMAP hBmp
)
{ 
    BITMAP      bmp; 
    PBITMAPINFO pbmi; 
    WORD        cClrBits; 

    // Retrieve the bitmap's color format, width, and height. 
    if (!GetObject(hBmp, sizeof(BITMAP), (LPSTR)&bmp)) 
        return NULL;

    // Convert the color format to a count of bits. 
    cClrBits = (WORD)(bmp.bmPlanes * bmp.bmBitsPixel); 
    if (cClrBits == 1) 
        cClrBits = 1; 
    else if (cClrBits <= 4) 
        cClrBits = 4; 
    else if (cClrBits <= 8) 
        cClrBits = 8; 
    else if (cClrBits <= 16) 
        cClrBits = 16; 
    else if (cClrBits <= 24) 
        cClrBits = 24; 
    else cClrBits = 32; 

    // Allocate memory for the BITMAPINFO structure. (This structure 
    // contains a BITMAPINFOHEADER structure and an array of RGBQUAD 
    // data structures.) 
    if (cClrBits != 24) 
    {
        pbmi = (PBITMAPINFO) LocalAlloc(LPTR, 
                                        sizeof(BITMAPINFOHEADER) + 
                                        sizeof(RGBQUAD) * (1<< cClrBits)); 
    }
    else 
    {
        // There is no RGBQUAD array for the 24-bit-per-pixel format. 
        pbmi = (PBITMAPINFO) LocalAlloc(LPTR, sizeof(BITMAPINFOHEADER)); 
    }
    
    // Initialize the fields in the BITMAPINFO structure. 
    pbmi->bmiHeader.biSize = sizeof(BITMAPINFOHEADER); 
    pbmi->bmiHeader.biWidth = bmp.bmWidth; 
    pbmi->bmiHeader.biHeight = bmp.bmHeight; 
    pbmi->bmiHeader.biPlanes = bmp.bmPlanes; 
    pbmi->bmiHeader.biBitCount = bmp.bmBitsPixel; 
    if (cClrBits < 24) 
        pbmi->bmiHeader.biClrUsed = (1<<cClrBits); 

    // If the bitmap is not compressed, set the BI_RGB flag. 
    pbmi->bmiHeader.biCompression = BI_RGB; 

    // Compute the number of bytes in the array of color 
    // indices and store the result in biSizeImage. 
    pbmi->bmiHeader.biSizeImage = (pbmi->bmiHeader.biWidth + 7) /8 
                                  * pbmi->bmiHeader.biHeight 
                                  * cClrBits; 
                                  
    // Set biClrImportant to 0, indicating that all of the 
    // device colors are important. 
    pbmi->bmiHeader.biClrImportant = 0; 
    return pbmi; 
} 
 
BOOL CreateBMPFile
(
    LPTSTR      pszFile, 
    PBITMAPINFO pbi, 
    HBITMAP     hBMP, 
    HDC         hDC
) 
{ 
    HANDLE              hf;                 // file handle 
    BITMAPFILEHEADER    hdr;                // bitmap file-header 
    PBITMAPINFOHEADER   pbih;               // bitmap info-header 
    LPBYTE              lpBits;             // memory pointer 
    DWORD               dwTotal;            // total count of bytes 
    DWORD               cb;                 // incremental count of bytes 
    BYTE                *hp;                // byte pointer 
    DWORD               dwTmp; 

    pbih = (PBITMAPINFOHEADER) pbi; 
    lpBits = (LPBYTE) GlobalAlloc(GMEM_FIXED, pbih->biSizeImage);

    if (!lpBits) 
        return FALSE;

    // Retrieve the color table (RGBQUAD array) and the bits 
    // (array of palette indices) from the DIB. 
    if (!GetDIBits(hDC, hBMP, 0, (WORD) pbih->biHeight, lpBits, pbi, DIB_RGB_COLORS)) 
    {
        return FALSE;
    }

    // Create the .BMP file. 
    hf = CreateFile(pszFile, 
                    GENERIC_READ | GENERIC_WRITE, 
                    (DWORD) 0, 
                    NULL, 
                    CREATE_ALWAYS, 
                    FILE_ATTRIBUTE_NORMAL, 
                    (HANDLE) NULL); 
    if (hf == INVALID_HANDLE_VALUE) 
        return FALSE;
        
    hdr.bfType = 0x4d42;        // 0x42 = "B" 0x4d = "M" 
    // Compute the size of the entire file. 
    hdr.bfSize = (DWORD) (sizeof(BITMAPFILEHEADER) + 
                 pbih->biSize + pbih->biClrUsed 
                 * sizeof(RGBQUAD) + pbih->biSizeImage); 
    hdr.bfReserved1 = 0; 
    hdr.bfReserved2 = 0; 

    // Compute the offset to the array of color indices. 
    hdr.bfOffBits = (DWORD) sizeof(BITMAPFILEHEADER) + 
                    pbih->biSize + pbih->biClrUsed 
                    * sizeof (RGBQUAD); 

    // Copy the BITMAPFILEHEADER into the .BMP file. 
    if (!WriteFile(hf, (LPVOID) &hdr, sizeof(BITMAPFILEHEADER), 
        (LPDWORD) &dwTmp,  NULL)) 
    {
       return FALSE;
    }

    // Copy the BITMAPINFOHEADER and RGBQUAD array into the file. 
    if (!WriteFile(hf, (LPVOID) pbih, sizeof(BITMAPINFOHEADER) 
                  + pbih->biClrUsed * sizeof (RGBQUAD), 
                  (LPDWORD) &dwTmp, ( NULL))) 
    {                  
        return FALSE;
    }
    
    // Copy the array of color indices into the .BMP file. 
    dwTotal = cb = pbih->biSizeImage; 
    hp = lpBits; 
    if (!WriteFile(hf, (LPSTR) hp, (int) cb, (LPDWORD) &dwTmp,NULL)) 
    {
        return FALSE;
    }
    
    // Close the .BMP file. 
     if (!CloseHandle(hf)) 
     {
        return FALSE;
     }
     
    // Free memory. 
    GlobalFree((HGLOBAL)lpBits);
    
    return TRUE;
}
 
 
BOOL CopyBitmapRectToFile
(
    HBITMAP hbm, 
    LPRECT  lpRect,
    LPTSTR  lpszFileName
)
{
    HDC         hSrcDC, hDestDC;         // screen DC and memory DC
    HDC         hScreenDC;
    HBITMAP     hBitmap, hOldBitmap, hOldSrcBitmap; 
    PBITMAPINFO pbmi; 
    BOOL        bRet;
        
    // check for an empty rectangle
    if (IsRectEmpty(lpRect))
      return FALSE;

    // get the Source Window DC and create
    // a memory DC compatible to screen DC
    hScreenDC = GetDC(NULL);
    hSrcDC = CreateCompatibleDC(hScreenDC);
    hDestDC = CreateCompatibleDC(hScreenDC);
    
    // create a dest bitmap
    hBitmap = CreateCompatibleBitmap(hScreenDC, RECTWIDTH(*lpRect), RECTHEIGHT(*lpRect));

    // select new bitmap into memory DC
    hOldBitmap = (HBITMAP)SelectObject(hDestDC, hBitmap);

    // Select the passed in BMP into the SrcDC
    hOldSrcBitmap = (HBITMAP)SelectObject(hSrcDC, hbm);
    
    // bitblt screen DC to memory DC
    BitBlt(hDestDC, 
           0, 
           0, 
           RECTWIDTH(*lpRect), 
           RECTHEIGHT(*lpRect), 
           hSrcDC, 
           lpRect->left, 
           lpRect->top, 
           SRCCOPY);

    pbmi =  CreateBitmapInfoStruct(hBitmap);
    bRet = CreateBMPFile(lpszFileName,  pbmi,  hBitmap, hDestDC);
    LocalFree(pbmi);
    
    // clean up 
    DeleteObject(SelectObject(hDestDC, hOldBitmap));
    SelectObject(hSrcDC, hOldSrcBitmap);

    DeleteDC(hSrcDC);
    DeleteDC(hDestDC);

    ReleaseDC(NULL, hScreenDC);

    return bRet;
}