text: /*
   * Copyright (C) 2007, 2008 Apple Inc.  All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
   * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
   * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
   */
  
  #include "config.h"
  #include "DragImage.h"
  
  #include "BitmapInfo.h"
  #include "CachedImage.h"
  #include "GraphicsContextCG.h"
  #include "HWndDC.h"
  #include "Image.h"
  
  #include <CoreGraphics/CoreGraphics.h>
  #include <wtf/RetainPtr.h>
  
  #include <windows.h>
  
  namespace WebCore {
  
  void deallocContext(CGContextRef target)
  {
      CGContextRelease(target);
  }
  
  HBITMAP allocImage(HDC dc, IntSize size, CGContextRef *targetRef)
  {
      BitmapInfo bmpInfo = BitmapInfo::create(size);
  
      LPVOID bits;
      HBITMAP hbmp = CreateDIBSection(dc, &bmpInfo, DIB_RGB_COLORS, &bits, 0, 0);
  
      if (!targetRef)
          return hbmp;
  
      CGContextRef bitmapContext = CGBitmapContextCreate(bits, bmpInfo.bmiHeader.biWidth, bmpInfo.bmiHeader.biHeight, 8,
                                                         bmpInfo.bmiHeader.biWidth * 4, deviceRGBColorSpaceRef(),
                                                         kCGBitmapByteOrder32Little | kCGImageAlphaNoneSkipFirst);
      if (!bitmapContext) {
          DeleteObject(hbmp);
          return 0;
      }
  
      *targetRef = bitmapContext;
      return hbmp;
  }
  
  static CGContextRef createCgContextFromBitmap(HBITMAP bitmap)
  {
      BITMAP info;
      GetObject(bitmap, sizeof(info), &info);
      ASSERT(info.bmBitsPixel == 32);
  
      CGContextRef bitmapContext = CGBitmapContextCreate(info.bmBits, info.bmWidth, info.bmHeight, 8,
                                                         info.bmWidthBytes, deviceRGBColorSpaceRef(), kCGBitmapByteOrder32Little | kCGImageAlphaNoneSkipFirst);
      return bitmapContext;
  }
  
  DragImageRef scaleDragImage(DragImageRef image, FloatSize scale)
  {
      // FIXME: due to the way drag images are done on windows we need 
      // to preprocess the alpha channel <rdar://problem/5015946>
  
      if (!image)
          return 0;
      CGContextRef targetContext;
      CGContextRef srcContext;
      CGImageRef srcImage;
      IntSize srcSize = dragImageSize(image);
      IntSize dstSize(static_cast<int>(srcSize.width() * scale.width()), static_cast<int>(srcSize.height() * scale.height()));
      HBITMAP hbmp = 0;
      HWndDC dc(0);
      HDC dstDC = CreateCompatibleDC(dc);
      if (!dstDC)
          goto exit;
  
      hbmp = allocImage(dstDC, dstSize, &targetContext);
      if (!hbmp)
          goto exit;
  
      srcContext = createCgContextFromBitmap(image);
      srcImage = CGBitmapContextCreateImage(srcContext);
      CGRect rect;
      rect.origin.x = 0;
      rect.origin.y = 0;
      rect.size = dstSize;
      CGContextDrawImage(targetContext, rect, srcImage);
      CGImageRelease(srcImage);
      CGContextRelease(srcContext);
      CGContextRelease(targetContext);
      ::DeleteObject(image);
      image = 0;
  
  exit:
      if (!hbmp)
          hbmp = image;
      if (dstDC)
          DeleteDC(dstDC);
      return hbmp;
  }
      
  DragImageRef createDragImageFromImage(Image* img, RespectImageOrientationEnum)
  {
      HBITMAP hbmp = 0;
      HWndDC dc(0);
      HDC workingDC = CreateCompatibleDC(dc);
      CGContextRef drawContext = 0;
      if (!workingDC)
          goto exit;
  
      hbmp = allocImage(workingDC, img->size(), &drawContext);
  
      if (!hbmp)
          goto exit;
  
      if (!drawContext) {
          ::DeleteObject(hbmp);
          hbmp = 0;
      }
  
      CGImageRef srcImage = img->getCGImageRef();
      CGRect rect;
      rect.size = img->size();
      rect.origin.x = 0;
      rect.origin.y = -rect.size.height;
      static const CGFloat white [] = {1.0, 1.0, 1.0, 1.0};
      CGContextScaleCTM(drawContext, 1, -1);
      CGContextSetFillColor(drawContext, white);
      CGContextFillRect(drawContext, rect);
      if (srcImage) {
          CGContextSetBlendMode(drawContext, kCGBlendModeNormal);
          CGContextDrawImage(drawContext, rect, srcImage);
      }
      CGContextRelease(drawContext);
  
  exit:
      if (workingDC)
          DeleteDC(workingDC);
      return hbmp;
  }
      
  }
  