#include "pch.h"
#include "DwmSharedSurfaceFrameSource.h"
#include "App.h"


extern std::shared_ptr<spdlog::logger> logger;


bool DwmSharedSurfaceFrameSource::Initialize() {
	HMODULE user32 = GetModuleHandle(L"user32");
	if (!user32) {
		SPDLOG_LOGGER_ERROR(logger, MakeWin32ErrorMsg("获取 User32 模块句柄失败"));
		return false;
	}

	_dwmGetDxSharedSurface = (_DwmGetDxSharedSurfaceFunc*)GetProcAddress(user32, "DwmGetDxSharedSurface");

	if (!_dwmGetDxSharedSurface) {
		SPDLOG_LOGGER_ERROR(logger, MakeWin32ErrorMsg("获取函数 DwmGetDxSharedSurface 地址失败"));
		return false;
	}

	_d3dDC = App::GetInstance().GetRenderer().GetD3DDC();
	_d3dDevice = App::GetInstance().GetRenderer().GetD3DDevice();
	_hwndSrc = App::GetInstance().GetHwndSrc();

	RECT srcWindowRect;
	if (!GetWindowRect(_hwndSrc, &srcWindowRect)) {
		SPDLOG_LOGGER_ERROR(logger, MakeWin32ErrorMsg("GetWindowRect 失败"));
		return false;
	}
	const RECT srcClientRect = App::GetInstance().GetSrcClientRect();
	
	_clientInFrame = {
		UINT(srcClientRect.left - srcWindowRect.left),
		UINT(srcClientRect.top - srcWindowRect.top),
		0,
		UINT(srcClientRect.right - srcWindowRect.left),
		UINT(srcClientRect.bottom - srcWindowRect.top),
		1
	};

	D3D11_TEXTURE2D_DESC desc{};
	desc.Format = DXGI_FORMAT_B8G8R8A8_UNORM;
	desc.Width = srcClientRect.right - srcClientRect.left;
	desc.Height = srcClientRect.bottom - srcClientRect.top;
	desc.MipLevels = 1;
	desc.ArraySize = 1;
	desc.SampleDesc.Count = 1;
	desc.SampleDesc.Quality = 0;
	desc.BindFlags = D3D11_BIND_SHADER_RESOURCE | D3D11_BIND_RENDER_TARGET;
	HRESULT hr = _d3dDevice->CreateTexture2D(&desc, nullptr, &_output);
	if (FAILED(hr)) {
		SPDLOG_LOGGER_CRITICAL(logger, MakeComErrorMsg("创建 Texture2D 失败", hr));
		return false;
	}

	SPDLOG_LOGGER_INFO(logger, "DwmSharedSurfaceFrameSource 初始化完成");
	return true;
}

ComPtr<ID3D11Texture2D> DwmSharedSurfaceFrameSource::GetOutput() {
	return _output;
}

bool DwmSharedSurfaceFrameSource::Update() {
	HANDLE sharedTextureHandle = NULL;
	if (!_dwmGetDxSharedSurface(_hwndSrc, &sharedTextureHandle, nullptr, nullptr, nullptr, nullptr)
		|| !sharedTextureHandle
	) {
		SPDLOG_LOGGER_ERROR(logger, MakeWin32ErrorMsg("DwmGetDxSharedSurface 失败"));
		return false;
	}

	ComPtr<ID3D11Texture2D> sharedTexture;
	HRESULT hr = _d3dDevice->OpenSharedResource(sharedTextureHandle, IID_PPV_ARGS(&sharedTexture));
	if (FAILED(hr)) {
		SPDLOG_LOGGER_ERROR(logger, MakeComErrorMsg("OpenSharedResource 失败", hr));
		return false;
	}
	
	_d3dDC->CopySubresourceRegion(_output.Get(), 0, 0, 0, 0, sharedTexture.Get(), 0, &_clientInFrame);

	return true;
}