#include "commonheaders.h"

void HalfBitmap32Alpha(HBITMAP hBitmap)
{
	BITMAP bmp;
	GetObject(hBitmap, sizeof(bmp), &bmp);
	if (bmp.bmBitsPixel != 32)
		return;

	DWORD dwLen = bmp.bmWidth * bmp.bmHeight * (bmp.bmBitsPixel / 8);
	BYTE *p = (BYTE *)malloc(dwLen);
	if (p == NULL)
		return;
	memset(p, 0, dwLen);

	GetBitmapBits(hBitmap, dwLen, p);

	for (int y = 0; y < bmp.bmHeight; ++y) {
		BYTE *px = p + bmp.bmWidth * 4 * y;

		for (int x = 0; x < bmp.bmWidth; ++x) {
			px[3] >>= 1;
			px += 4;
		}
	}

	SetBitmapBits(hBitmap, dwLen, p);
	free(p);
}


// Make a bitmap all transparent, but only if it is a 32bpp
void MakeBmpTransparent(HBITMAP hBitmap)
{
	BITMAP bmp;
	GetObject(hBitmap, sizeof(bmp), &bmp);
	if (bmp.bmBitsPixel != 32)
		return;

	DWORD dwLen = bmp.bmWidth * bmp.bmHeight * (bmp.bmBitsPixel / 8);
	BYTE *p = (BYTE *)malloc(dwLen);
	if (p == NULL)
		return;

	memset(p, 0, dwLen);
	SetBitmapBits(hBitmap, dwLen, p);

	free(p);
}

// Correct alpha from bitmaps loaded without it (it cames with 0 and should be 255)
void CorrectBitmap32Alpha(HBITMAP hBitmap, BOOL force)
{
	BITMAP bmp;
	DWORD dwLen;
	BYTE *p;
	int x, y;
	BOOL fixIt;

	GetObject(hBitmap, sizeof(bmp), &bmp);

	if (bmp.bmBitsPixel != 32)
		return;

	dwLen = bmp.bmWidth * bmp.bmHeight * (bmp.bmBitsPixel / 8);
	p = (BYTE *)malloc(dwLen);
	if (p == NULL)
		return;
	memset(p, 0, dwLen);

	GetBitmapBits(hBitmap, dwLen, p);

	fixIt = TRUE;
	for (y = 0; fixIt && y < bmp.bmHeight; ++y) {
		BYTE *px = p + bmp.bmWidth * 4 * y;

		for (x = 0; fixIt && x < bmp.bmWidth; ++x) {
			if (px[3] != 0 && !force) {
				fixIt = FALSE;
			}
			else {
				if (px[0] != 0 || px[1] != 0 || px[2] != 0)
					px[3] = 255;
			}

			px += 4;
		}
	}

	if (fixIt)
		SetBitmapBits(hBitmap, dwLen, p);

	free(p);
}


HBITMAP CopyBitmapTo32(HBITMAP hBitmap)
{
	BITMAPINFO RGB32BitsBITMAPINFO;
	BYTE * ptPixels;
	HBITMAP hDirectBitmap;

	BITMAP bmp;
	DWORD dwLen;
	BYTE *p;

	GetObject(hBitmap, sizeof(bmp), &bmp);

	dwLen = bmp.bmWidth * bmp.bmHeight * 4;
	p = (BYTE *)malloc(dwLen);
	if (p == NULL)
		return NULL;

	// Create bitmap
	ZeroMemory(&RGB32BitsBITMAPINFO, sizeof(BITMAPINFO));
	RGB32BitsBITMAPINFO.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
	RGB32BitsBITMAPINFO.bmiHeader.biWidth = bmp.bmWidth;
	RGB32BitsBITMAPINFO.bmiHeader.biHeight = bmp.bmHeight;
	RGB32BitsBITMAPINFO.bmiHeader.biPlanes = 1;
	RGB32BitsBITMAPINFO.bmiHeader.biBitCount = 32;

	hDirectBitmap = CreateDIBSection(NULL,
												(BITMAPINFO *)&RGB32BitsBITMAPINFO,
												DIB_RGB_COLORS,
												(void **)&ptPixels,
												NULL, 0);

	// Copy data
	if (bmp.bmBitsPixel != 32) {
		HDC hdcOrig, hdcDest;
		HBITMAP oldOrig, oldDest;

		hdcOrig = CreateCompatibleDC(NULL);
		oldOrig = (HBITMAP)SelectObject(hdcOrig, hBitmap);

		hdcDest = CreateCompatibleDC(NULL);
		oldDest = (HBITMAP)SelectObject(hdcDest, hDirectBitmap);

		BitBlt(hdcDest, 0, 0, bmp.bmWidth, bmp.bmHeight, hdcOrig, 0, 0, SRCCOPY);

		SelectObject(hdcDest, oldDest);
		DeleteObject(hdcDest);
		SelectObject(hdcOrig, oldOrig);
		DeleteObject(hdcOrig);

		// Set alpha
		CorrectBitmap32Alpha(hDirectBitmap, FALSE);
	}
	else {
		GetBitmapBits(hBitmap, dwLen, p);
		SetBitmapBits(hDirectBitmap, dwLen, p);
	}

	free(p);

	return hDirectBitmap;
}


HBITMAP CreateBitmap32(int cx, int cy)
{
	BITMAPINFO RGB32BitsBITMAPINFO;
	UINT * ptPixels;
	HBITMAP DirectBitmap;

	ZeroMemory(&RGB32BitsBITMAPINFO, sizeof(BITMAPINFO));
	RGB32BitsBITMAPINFO.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
	RGB32BitsBITMAPINFO.bmiHeader.biWidth = cx;//bm.bmWidth;
	RGB32BitsBITMAPINFO.bmiHeader.biHeight = cy;//bm.bmHeight;
	RGB32BitsBITMAPINFO.bmiHeader.biPlanes = 1;
	RGB32BitsBITMAPINFO.bmiHeader.biBitCount = 32;

	DirectBitmap = CreateDIBSection(NULL,
											  (BITMAPINFO *)&RGB32BitsBITMAPINFO,
											  DIB_RGB_COLORS,
											  (void **)&ptPixels,
											  NULL, 0);
	return DirectBitmap;
}


BOOL MakeBitmap32(HBITMAP *hBitmap)
{
	BITMAP bmp;

	GetObject(*hBitmap, sizeof(bmp), &bmp);

	if (bmp.bmBitsPixel != 32) {
		// Convert to 32 bpp
		HBITMAP hBmpTmp = CopyBitmapTo32(*hBitmap);
		DeleteObject(*hBitmap);
		*hBitmap = hBmpTmp;
	}

	return TRUE;
}

#define GET_PIXEL(__P__, __X__, __Y__)(__P__ + width * 4 * (__Y__) + 4 * (__X__))

BOOL MakeGrayscale(HBITMAP *hBitmap)
{
	BYTE *p = NULL;
	BYTE *p1;
	DWORD dwLen;
	int width, height, x, y;
	BITMAP bmp;

	GetObject(*hBitmap, sizeof(bmp), &bmp);
	width = bmp.bmWidth;
	height = bmp.bmHeight;

	dwLen = width * height * 4;
	p = (BYTE *)malloc(dwLen);
	if (p == NULL) {
		return FALSE;
	}

	if (bmp.bmBitsPixel != 32) {
		// Convert to 32 bpp
		HBITMAP hBmpTmp = CopyBitmapTo32(*hBitmap);
		DeleteObject(*hBitmap);
		*hBitmap = hBmpTmp;
	}
	GetBitmapBits(*hBitmap, dwLen, p);

	// Make grayscale
	for (y = 0; y < height; y++) {
		for (x = 0; x < width; x++) {
			p1 = GET_PIXEL(p, x, y);
			p1[0] = p1[1] = p1[2] = (p1[0] + p1[1] + p1[2]) / 3;
		}
	}

	dwLen = SetBitmapBits(*hBitmap, dwLen, p);
	free(p);

	return TRUE;
}

HICON MakeHalfAlphaIcon(HICON SourceIcon)
{
	HICON TempIcon = CopyIcon(SourceIcon);

	ICONINFO TargetIconInfo;
	if (!GetIconInfo(TempIcon, &TargetIconInfo))
		return NULL;

	BITMAP TargetBitmapInfo;
	if (!GetObject(TargetIconInfo.hbmColor, sizeof(BITMAP), &TargetBitmapInfo))
		return NULL;

	MakeBitmap32(&TargetIconInfo.hbmColor);
	HalfBitmap32Alpha(TargetIconInfo.hbmColor);
	HICON TargetIcon = CreateIconIndirect(&TargetIconInfo);

	DestroyIcon(TempIcon);
	DeleteObject(TargetIconInfo.hbmColor);
	DeleteObject(TargetIconInfo.hbmMask);
	return TargetIcon;
}

HICON MakeGrayscaleIcon(HICON SourceIcon)
{
	HICON TempIcon = CopyIcon(SourceIcon);

	ICONINFO TargetIconInfo;
	BITMAP TargetBitmapInfo;
	if (!GetIconInfo(TempIcon, &TargetIconInfo) || GetObject(TargetIconInfo.hbmColor, sizeof(BITMAP), &TargetBitmapInfo) == 0)
		return NULL;

	MakeGrayscale(&TargetIconInfo.hbmColor);

	HICON TargetIcon = CreateIconIndirect(&TargetIconInfo);
	DestroyIcon(TempIcon);

	return TargetIcon;
}


HICON BindOverlayIcon(HICON SourceIcon, HICON OverlayIcon)
{
	ICONINFO OverlayIconInfo, TargetIconInfo;
	BITMAP OverlayBitmapInfo, TargetBitmapInfo;
	HBITMAP OldOverlayBitmap, OldTargetBitmap;
	HICON TargetIcon, TempIcon;
	HDC OverlayDC, TargetDC;
	BLENDFUNCTION bf = { 0, 0, 255, 1 };

	TempIcon = CopyIcon(SourceIcon);
	if (!GetIconInfo(TempIcon, &TargetIconInfo))
		return NULL;

	MakeBitmap32(&TargetIconInfo.hbmColor);
	CorrectBitmap32Alpha(TargetIconInfo.hbmColor, FALSE);
	GetObject(TargetIconInfo.hbmColor, sizeof(BITMAP), &TargetBitmapInfo);

	if (!GetIconInfo(OverlayIcon, &OverlayIconInfo) || !GetObject(OverlayIconInfo.hbmColor, sizeof(BITMAP), &OverlayBitmapInfo))
		return NULL;

	TargetDC = CreateCompatibleDC(NULL);
	OldTargetBitmap = (HBITMAP)SelectObject(TargetDC, TargetIconInfo.hbmColor);

	OverlayDC = CreateCompatibleDC(NULL);
	OldOverlayBitmap = (HBITMAP)SelectObject(OverlayDC, OverlayIconInfo.hbmColor);

	AlphaBlend(TargetDC, 0, 0, TargetBitmapInfo.bmWidth, TargetBitmapInfo.bmHeight,
				  OverlayDC, 0, 0, OverlayBitmapInfo.bmWidth, OverlayBitmapInfo.bmHeight, bf);

	SelectObject(TargetDC, TargetIconInfo.hbmMask);
	SelectObject(OverlayDC, OverlayIconInfo.hbmMask);

	BitBlt(TargetDC, 0, 0, TargetBitmapInfo.bmWidth, TargetBitmapInfo.bmHeight,
			 OverlayDC, 0, 0, SRCCOPY);

	TargetIcon = CreateIconIndirect(&TargetIconInfo);
	DestroyIcon(TempIcon);

	SelectObject(TargetDC, OldTargetBitmap);
	DeleteObject(TargetIconInfo.hbmColor);
	DeleteObject(TargetIconInfo.hbmMask);
	DeleteDC(TargetDC);

	SelectObject(OverlayDC, OldOverlayBitmap);
	DeleteObject(OverlayIconInfo.hbmColor);
	DeleteObject(OverlayIconInfo.hbmMask);
	DeleteDC(OverlayDC);

	return TargetIcon;
}