#include "win32_screen_shots.h"

namespace _wss
{
	cv::Mat get_window_bits(HWND h)
	{

		//printf("´°Ì壺%d \n",h==NULL?0: 1);
		cv::Mat result;
		HBITMAP bit = nullptr;
		RECT rect{ 0 };
		int width = 0, height = 0;
		HDC hdc = nullptr, hdc_compatible = nullptr;
		BITMAP info{ 0 };
		int channels = 0;

		if (h == nullptr)
			return result;

		do
		{
			if (GetWindowRect(h, &rect) == FALSE)
				break;

			width = abs( rect.right - rect.left);
			height =abs( rect.bottom - rect.top);

			hdc = GetWindowDC(h);
			if (hdc == nullptr)
				break;

			hdc_compatible = CreateCompatibleDC(hdc);
			if (hdc_compatible == nullptr)
				break;

			bit = CreateCompatibleBitmap(hdc, width, height);
			if (bit == nullptr)
				break;

			SelectObject(hdc_compatible, bit);

			if (BitBlt(hdc_compatible, 0, 0, width, height, hdc, 0, 0, SRCCOPY) == FALSE)
				break;

			if (GetObjectA(bit, sizeof(BITMAP), &info) == 0)
				break;

			channels = info.bmBitsPixel == 1 ? 1 : info.bmBitsPixel / 8;
			result.create(cv::Size(info.bmWidth, info.bmHeight), CV_MAKETYPE(CV_8U, channels));
			if (GetBitmapBits(bit, info.bmHeight * info.bmWidth * channels, result.data) == 0)
			  break;
			//µ¥Í¨µÀͼ
			//result.create(cv::Size(info.bmWidth, info.bmHeight), CV_8UC1);
			//if (GetBitmapBits(bit, info.bmHeight * info.bmWidth * channels, result.data) == 0)
			//	break;
		} while (false);

		if (hdc)
			ReleaseDC(h, hdc);

		if (hdc_compatible)
			DeleteDC(hdc_compatible);

		if (bit)
			DeleteObject(bit);

		return result;
	}

	cv::Mat screen_shot_by_window(HWND h)
	{
		return get_window_bits(h);
	}

	cv::Mat screen_shot_by_window(std::string name)
	{
		return get_window_bits(FindWindowA(0, name.c_str()));
	}

	cv::Mat screen_shot_by_full_screen(HWND h)
	{
		cv::Mat desktop;

		if (h == nullptr)
			return desktop;

		desktop = get_window_bits(GetDesktopWindow());
		if (desktop.empty())
			return desktop;

		RECT rect{ 0 };
		if (GetWindowRect(h, &rect) == FALSE)
			return desktop;

		if (rect.left < 0)
			rect.left = 0;
		if (rect.top < 0)
			rect.top = 0;

		int width = rect.right - rect.left;
		int height = rect.bottom - rect.top;
		cv::Mat result = desktop(cv::Rect(rect.left, rect.top, width, height));
		return result;
	}

	cv::Mat screen_shot_by_full_screen(std::string name)
	{
		return screen_shot_by_full_screen(FindWindowA(0, name.c_str()));
	}
}