// Copyright 2010 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.

#include <algorithm>

#include "Common/CommonTypes.h"
#include "Common/MsgHandler.h"
#include "VideoBackends/D3D/D3DBase.h"
#include "VideoBackends/D3D/D3DTexture.h"

namespace DX11
{

namespace D3D
{

void ReplaceRGBATexture2D(ID3D11Texture2D* pTexture, const u8* buffer, unsigned int width, unsigned int height, unsigned int src_pitch, unsigned int level, D3D11_USAGE usage)
{
	if (usage == D3D11_USAGE_DYNAMIC || usage == D3D11_USAGE_STAGING)
	{
		D3D11_MAPPED_SUBRESOURCE map;
		D3D::context->Map(pTexture, level, D3D11_MAP_WRITE_DISCARD, 0, &map);
		if (src_pitch == map.RowPitch)
		{
			memcpy(map.pData, buffer, map.RowPitch * height);
		}
		else
		{
			// Source row size is aligned to texture block size. This can result in a different
			// pitch to what the driver returns, so copy whichever is smaller.
			unsigned int copy_size = std::min(src_pitch, map.RowPitch);
			for (unsigned int y = 0; y < height; ++y)
				memcpy((u8*)map.pData + y * map.RowPitch, buffer + y * src_pitch, copy_size);
		}
		D3D::context->Unmap(pTexture, level);
	}
	else
	{
		D3D11_BOX dest_region = CD3D11_BOX(0, 0, 0, width, height, 1);
		D3D::context->UpdateSubresource(pTexture, level, &dest_region, buffer, src_pitch, src_pitch * height);
	}
}

}  // namespace

D3DTexture2D* D3DTexture2D::Create(unsigned int width, unsigned int height, D3D11_BIND_FLAG bind, D3D11_USAGE usage, DXGI_FORMAT fmt, unsigned int levels, unsigned int slices, D3D11_SUBRESOURCE_DATA* data)
{
	ID3D11Texture2D* pTexture = nullptr;
	HRESULT hr;

	D3D11_CPU_ACCESS_FLAG cpuflags;
	if (usage == D3D11_USAGE_STAGING)
		cpuflags = (D3D11_CPU_ACCESS_FLAG)((int)D3D11_CPU_ACCESS_WRITE|(int)D3D11_CPU_ACCESS_READ);
	else if (usage == D3D11_USAGE_DYNAMIC)
		cpuflags = D3D11_CPU_ACCESS_WRITE;
	else
		cpuflags = (D3D11_CPU_ACCESS_FLAG)0;
	D3D11_TEXTURE2D_DESC texdesc = CD3D11_TEXTURE2D_DESC(fmt, width, height, slices, levels, bind, usage, cpuflags);
	hr = D3D::device->CreateTexture2D(&texdesc, data, &pTexture);
	if (FAILED(hr))
	{
		PanicAlert("Failed to create texture at %s, line %d: hr=%#x\n", __FILE__, __LINE__, hr);
		return nullptr;
	}

	D3DTexture2D* ret = new D3DTexture2D(pTexture, bind);
	SAFE_RELEASE(pTexture);
	return ret;
}

void D3DTexture2D::AddRef()
{
	++ref;
}

UINT D3DTexture2D::Release()
{
	--ref;
	if (ref == 0)
	{
		delete this;
		return 0;
	}
	return ref;
}

ID3D11Texture2D* &D3DTexture2D::GetTex() { return tex; }
ID3D11ShaderResourceView* &D3DTexture2D::GetSRV() { return srv; }
ID3D11RenderTargetView* &D3DTexture2D::GetRTV() { return rtv; }
ID3D11DepthStencilView* &D3DTexture2D::GetDSV() { return dsv; }

D3DTexture2D::D3DTexture2D(ID3D11Texture2D* texptr, D3D11_BIND_FLAG bind,
							DXGI_FORMAT srv_format, DXGI_FORMAT dsv_format, DXGI_FORMAT rtv_format, bool multisampled)
							: ref(1), tex(texptr), srv(nullptr), rtv(nullptr), dsv(nullptr)
{
	D3D11_SRV_DIMENSION srv_dim = multisampled ? D3D11_SRV_DIMENSION_TEXTURE2DMSARRAY : D3D11_SRV_DIMENSION_TEXTURE2DARRAY;
	D3D11_DSV_DIMENSION dsv_dim = multisampled ? D3D11_DSV_DIMENSION_TEXTURE2DMSARRAY : D3D11_DSV_DIMENSION_TEXTURE2DARRAY;
	D3D11_RTV_DIMENSION rtv_dim = multisampled ? D3D11_RTV_DIMENSION_TEXTURE2DMSARRAY : D3D11_RTV_DIMENSION_TEXTURE2DARRAY;
	D3D11_SHADER_RESOURCE_VIEW_DESC srv_desc = CD3D11_SHADER_RESOURCE_VIEW_DESC(srv_dim, srv_format);
	D3D11_DEPTH_STENCIL_VIEW_DESC dsv_desc = CD3D11_DEPTH_STENCIL_VIEW_DESC(dsv_dim, dsv_format);
	D3D11_RENDER_TARGET_VIEW_DESC rtv_desc = CD3D11_RENDER_TARGET_VIEW_DESC(rtv_dim, rtv_format);
	if (bind & D3D11_BIND_SHADER_RESOURCE)
		D3D::device->CreateShaderResourceView(tex, &srv_desc, &srv);
	if (bind & D3D11_BIND_RENDER_TARGET)
		D3D::device->CreateRenderTargetView(tex, &rtv_desc, &rtv);
	if (bind & D3D11_BIND_DEPTH_STENCIL)
		D3D::device->CreateDepthStencilView(tex, &dsv_desc, &dsv);
	tex->AddRef();
}

D3DTexture2D::~D3DTexture2D()
{
	SAFE_RELEASE(srv);
	SAFE_RELEASE(rtv);
	SAFE_RELEASE(dsv);
	SAFE_RELEASE(tex);
}

}  // namespace DX11