#include <Windows.h>
#include <stdio.h>
#include <algorithm>

struct CStopWatch final
{
	const char* title;
	LARGE_INTEGER frequency;
	LARGE_INTEGER startTime;

	CStopWatch( const char* pszTitle )
		: title( pszTitle )
	{
		::QueryPerformanceFrequency( &frequency );
		::QueryPerformanceCounter( &startTime );
	}
	~CStopWatch( void )
	{
		LARGE_INTEGER endTime;
		::QueryPerformanceCounter( &endTime );
		double elapsedSec = 1000 * (endTime.QuadPart - startTime.QuadPart) / (double)frequency.QuadPart;
		char buf[128];
		::sprintf_s( buf, "%.3f msec, %s\n", elapsedSec, title );
		::OutputDebugStringA( buf );
	}
};

constexpr size_t MAX_COUNT = 60;

void case_FillRect(HDC hDC, const RECT& rc)
{
	CStopWatch sw( __FUNCTION__ );
	for ( size_t n = 0; n < MAX_COUNT; n++ ) {
		COLORREF color = RGB(n, n, n);
		HBRUSH brush = ::CreateSolidBrush( color );
		::FillRect( hDC, &rc, brush );
		::DeleteObject( brush );
	}
}

void case_ExtTextOut(HDC hDC, const RECT& rc)
{
	CStopWatch sw( __FUNCTION__ );
	for ( size_t n = 0; n < MAX_COUNT; n++ ) {
		COLORREF color = RGB(n, n, n);
		COLORREF bkColorOld = ::SetBkColor( hDC, color );
		::ExtTextOutW( hDC, rc.left, rc.top, ETO_OPAQUE, &rc, L"", 0, NULL );
		::SetBkColor( hDC, bkColorOld );
	}
}

void case_PatBlt(HDC hDC, const RECT& rc)
{
	CStopWatch sw( __FUNCTION__ );
	for ( size_t n = 0; n < MAX_COUNT; n++ ) {
		COLORREF color = RGB(n, n, n);
		HBRUSH brush = ::CreateSolidBrush( color );
		HGDIOBJ brushOld = ::SelectObject( hDC, brush );
		::PatBlt( hDC, rc.left, rc.top, rc.right, rc.bottom, PATCOPY );
		::SelectObject( hDC, brushOld );
		::DeleteObject( brush );
	}
}

static void FillRect_DIB(DWORD* pDIBPixels, RECT rc, int cx, int cy, COLORREF color)
{
	LONG width = rc.right - rc.left;
	LONG height = rc.bottom - rc.top;

	if (rc.top < 0)
	{
		height += rc.top;
		rc.top = 0;
	}
	if (rc.left < 0)
	{
		width += rc.left;
		rc.left = 0;
	}
	if (rc.top >= cy || rc.left >= cx || height < 1 || width < 1)
	{
		return;
	}
	if (rc.left + width > cx)
	{
		width = cx - rc.left;
	}
	if (rc.top + height > cy)
	{
		height = cy - rc.top;
	}

	BYTE r = GetRValue(color);
	BYTE g = GetGValue(color);
	BYTE b = GetBValue(color);
	DWORD dwColor = (r << 16) | (g << 8) | b;

	pDIBPixels += cx * rc.top + rc.left;

	if (width == cx)
	{
		std::fill_n(pDIBPixels, cx * height, dwColor);
	}
	else
	{
		for (LONG i = 0; i < height; ++i)
		{
			std::fill_n(pDIBPixels, width, dwColor);
			pDIBPixels += cx;
		}
	}
}

void case_DIB(DWORD* pDIBPixels, const RECT& rc, int cx, int cy)
{
	CStopWatch sw( __FUNCTION__ );
	for ( size_t n = 0; n < MAX_COUNT; n++ ) {
		COLORREF color = RGB(n, n, n);
		::FillRect_DIB( pDIBPixels, rc, cx, cy, color );
	}
}

//! Main関数
int WINAPI wWinMain(
	HINSTANCE	hInstance,		//!< handle to current instance
	HINSTANCE	hPrevInstance,	//!< handle to previous instance
	LPWSTR		lpCmdLine,		//!< pointer to command line
	int			nCmdShow		//!< show state of window
)
{
	::SetProcessDPIAware();

	HWND hDesktopWnd = ::GetDesktopWindow();
	RECT rc;
	::GetWindowRect( hDesktopWnd, &rc );
	int cx = rc.right - rc.left;
	int cy = rc.bottom - rc.top;

	HDC hDesktopDC = ::GetDC( hDesktopWnd );
	HDC hCompatibleDC = ::CreateCompatibleDC( NULL );
	HBITMAP hCompatibleBitmap = ::CreateCompatibleBitmap( hCompatibleDC, cx, cy );
	HGDIOBJ hPrevObj = ::SelectObject( hCompatibleDC, hCompatibleBitmap );

	BITMAPINFO bmi = {0};
	BITMAPINFOHEADER& bmih = bmi.bmiHeader;
	bmih.biSize = sizeof(bmih);
	bmih.biBitCount = 32;
	bmih.biWidth = cx;
	bmih.biHeight = -cy;
	bmih.biPlanes = 1;
	bmih.biCompression = BI_RGB;
	bmih.biSizeImage = 0;
	bmih.biXPelsPerMeter = 0;
	bmih.biYPelsPerMeter = 0;
	bmih.biClrUsed = 0;
	bmih.biClrImportant = 0;
	void* pvBits = nullptr;
	HBITMAP hDIB = CreateDIBSection(
		NULL,
		&bmi,
		DIB_RGB_COLORS,
		&pvBits,
		NULL,
		0
	);


	for (int i = 0; i < 8; ++i)
	{
		char buff[64];
		sprintf_s(buff, "x, y, w, h : %d, %d, %d, %d\n", rc.left, rc.top, rc.right - rc.left, rc.bottom - rc.top);
		::OutputDebugStringA(buff);
		case_FillRect( hCompatibleDC, rc );
		case_ExtTextOut( hCompatibleDC, rc );
		case_PatBlt( hCompatibleDC, rc );
		case_DIB( (DWORD*)pvBits, rc, cx, cy );
		rc.right >>= 1;
		rc.bottom >>= 1;
	}

	::SelectObject( hCompatibleDC, hPrevObj );
	::DeleteObject( hCompatibleBitmap );
	::DeleteObject( hDIB );
	::DeleteDC( hCompatibleDC );
	::ReleaseDC( hDesktopWnd, hDesktopDC );
	return 0;
}