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

#include <memory>

#include "Common/CommonTypes.h"
#include "Common/MsgHandler.h"
#include "VideoBackends/D3D12/D3DBase.h"
#include "VideoBackends/D3D12/D3DCommandListManager.h"
#include "VideoBackends/D3D12/D3DDescriptorHeapManager.h"
#include "VideoBackends/D3D12/D3DStreamBuffer.h"
#include "VideoBackends/D3D12/D3DTexture.h"
#include "VideoBackends/D3D12/D3DUtil.h"
#include "VideoBackends/D3D12/FramebufferManager.h"
#include "VideoBackends/D3D12/Render.h"

namespace DX12
{
namespace D3D
{
constexpr size_t INITIAL_TEXTURE_UPLOAD_BUFFER_SIZE = 4 * 1024 * 1024;
constexpr size_t MAXIMUM_TEXTURE_UPLOAD_BUFFER_SIZE = 64 * 1024 * 1024;

static std::unique_ptr<D3DStreamBuffer> s_texture_upload_stream_buffer;

void CleanupPersistentD3DTextureResources()
{
  s_texture_upload_stream_buffer.reset();
}

void ReplaceRGBATexture2D(ID3D12Resource* texture12, const u8* buffer, unsigned int width,
                          unsigned int height, unsigned int src_pitch, unsigned int level,
                          D3D12_RESOURCE_STATES current_resource_state)
{
  const unsigned int upload_size =
      AlignValue(src_pitch, D3D12_TEXTURE_DATA_PITCH_ALIGNMENT) * height;

  ID3D12Resource* upload_buffer = nullptr;
  size_t upload_buffer_offset = 0;
  u8* dest_data = nullptr;

  if (upload_size > MAXIMUM_TEXTURE_UPLOAD_BUFFER_SIZE)
  {
    // If the texture is too large to fit in the upload buffer, create a temporary buffer instead.
    // This will only be the case for large (e.g. 8192x8192) textures from custom texture packs.
    CheckHR(D3D::device12->CreateCommittedResource(
        &CD3DX12_HEAP_PROPERTIES(D3D12_HEAP_TYPE_UPLOAD), D3D12_HEAP_FLAG_NONE,
        &CD3DX12_RESOURCE_DESC::Buffer(upload_size), D3D12_RESOURCE_STATE_GENERIC_READ, nullptr,
        IID_PPV_ARGS(&upload_buffer)));

    D3D12_RANGE read_range = {};
    CheckHR(upload_buffer->Map(0, &read_range, reinterpret_cast<void**>(&dest_data)));
  }
  else
  {
    if (!s_texture_upload_stream_buffer)
      s_texture_upload_stream_buffer = std::make_unique<D3DStreamBuffer>(
          INITIAL_TEXTURE_UPLOAD_BUFFER_SIZE, MAXIMUM_TEXTURE_UPLOAD_BUFFER_SIZE, nullptr);

    s_texture_upload_stream_buffer->AllocateSpaceInBuffer(upload_size,
                                                          D3D12_TEXTURE_DATA_PLACEMENT_ALIGNMENT);

    upload_buffer = s_texture_upload_stream_buffer->GetBuffer();
    upload_buffer_offset = s_texture_upload_stream_buffer->GetOffsetOfCurrentAllocation();
    dest_data =
        reinterpret_cast<u8*>(s_texture_upload_stream_buffer->GetCPUAddressOfCurrentAllocation());
  }

  ResourceBarrier(current_command_list, texture12, current_resource_state,
                  D3D12_RESOURCE_STATE_COPY_DEST, level);

  D3D12_PLACED_SUBRESOURCE_FOOTPRINT upload_footprint = {};
  u32 upload_rows = 0;
  u64 upload_row_size_in_bytes = 0;
  u64 upload_total_bytes = 0;

  D3D::device12->GetCopyableFootprints(&texture12->GetDesc(), level, 1, upload_buffer_offset,
                                       &upload_footprint, &upload_rows, &upload_row_size_in_bytes,
                                       &upload_total_bytes);

  const u8* src_data = reinterpret_cast<const u8*>(buffer);
  for (u32 y = 0; y < upload_rows; ++y)
  {
    memcpy(dest_data + upload_footprint.Footprint.RowPitch * y, src_data + src_pitch * y,
           upload_row_size_in_bytes);
  }

  D3D::current_command_list->CopyTextureRegion(
      &CD3DX12_TEXTURE_COPY_LOCATION(texture12, level), 0, 0, 0,
      &CD3DX12_TEXTURE_COPY_LOCATION(upload_buffer, upload_footprint), nullptr);

  ResourceBarrier(D3D::current_command_list, texture12, D3D12_RESOURCE_STATE_COPY_DEST,
                  current_resource_state, level);

  // Release temporary buffer after commands complete.
  // We block here because otherwise if there was a large number of texture uploads, we may run out
  // of memory.
  if (!s_texture_upload_stream_buffer ||
      upload_buffer != s_texture_upload_stream_buffer->GetBuffer())
  {
    D3D12_RANGE write_range = {0, upload_size};
    upload_buffer->Unmap(0, &write_range);

    D3D::command_list_mgr->ExecuteQueuedWork(true);

    upload_buffer->Release();
  }
}

}  // namespace

D3DTexture2D* D3DTexture2D::Create(unsigned int width, unsigned int height, u32 bind,
                                   DXGI_FORMAT fmt, unsigned int levels, unsigned int slices,
                                   D3D12_SUBRESOURCE_DATA* data)
{
  ID3D12Resource* texture12 = nullptr;

  D3D12_RESOURCE_DESC texdesc12 = CD3DX12_RESOURCE_DESC::Tex2D(fmt, width, height, slices, levels);

  D3D12_CLEAR_VALUE optimized_clear_value = {};
  optimized_clear_value.Format = fmt;

  if (bind & TEXTURE_BIND_FLAG_RENDER_TARGET)
  {
    texdesc12.Flags |= D3D12_RESOURCE_FLAG_ALLOW_RENDER_TARGET;
    optimized_clear_value.Color[0] = 0.0f;
    optimized_clear_value.Color[1] = 0.0f;
    optimized_clear_value.Color[2] = 0.0f;
    optimized_clear_value.Color[3] = 1.0f;
  }

  if (bind & TEXTURE_BIND_FLAG_DEPTH_STENCIL)
  {
    texdesc12.Flags |= D3D12_RESOURCE_FLAG_ALLOW_DEPTH_STENCIL;
    optimized_clear_value.DepthStencil.Depth = 0.0f;
    optimized_clear_value.DepthStencil.Stencil = 0;
  }

  CheckHR(D3D::device12->CreateCommittedResource(
      &CD3DX12_HEAP_PROPERTIES(D3D12_HEAP_TYPE_DEFAULT), D3D12_HEAP_FLAG_NONE,
      &CD3DX12_RESOURCE_DESC(texdesc12), D3D12_RESOURCE_STATE_PIXEL_SHADER_RESOURCE,
      &optimized_clear_value, IID_PPV_ARGS(&texture12)));

  D3D::SetDebugObjectName12(texture12, "Texture created via D3DTexture2D::Create");
  D3DTexture2D* ret =
      new D3DTexture2D(texture12, bind, DXGI_FORMAT_UNKNOWN, DXGI_FORMAT_UNKNOWN,
                       DXGI_FORMAT_UNKNOWN, false, D3D12_RESOURCE_STATE_PIXEL_SHADER_RESOURCE);

  if (data)
  {
    DX12::D3D::ReplaceRGBATexture2D(texture12, reinterpret_cast<const u8*>(data->pData), width,
                                    height, static_cast<unsigned int>(data->RowPitch), 0,
                                    D3D12_RESOURCE_STATE_PIXEL_SHADER_RESOURCE);
  }

  SAFE_RELEASE(texture12);
  return ret;
}

void D3DTexture2D::AddRef()
{
  m_ref.fetch_add(1);
}

UINT D3DTexture2D::Release()
{
  // fetch_sub returns the value held before the subtraction.
  if (m_ref.fetch_sub(1) == 1)
  {
    delete this;
    return 0;
  }
  return m_ref.load();
}

D3D12_RESOURCE_STATES D3DTexture2D::GetResourceUsageState() const
{
  return m_resource_state;
}

bool D3DTexture2D::GetMultisampled() const
{
  return m_multisampled;
}

ID3D12Resource* D3DTexture2D::GetTex12() const
{
  return m_tex12;
}

D3D12_CPU_DESCRIPTOR_HANDLE D3DTexture2D::GetSRV12CPU() const
{
  return m_srv12_cpu;
}

D3D12_GPU_DESCRIPTOR_HANDLE D3DTexture2D::GetSRV12GPU() const
{
  return m_srv12_gpu;
}

D3D12_CPU_DESCRIPTOR_HANDLE D3DTexture2D::GetSRV12GPUCPUShadow() const
{
  return m_srv12_gpu_cpu_shadow;
}

D3D12_CPU_DESCRIPTOR_HANDLE D3DTexture2D::GetDSV12() const
{
  return m_dsv12;
}

D3D12_CPU_DESCRIPTOR_HANDLE D3DTexture2D::GetRTV12() const
{
  return m_rtv12;
}

D3DTexture2D::D3DTexture2D(ID3D12Resource* texptr, u32 bind, DXGI_FORMAT srv_format,
                           DXGI_FORMAT dsv_format, DXGI_FORMAT rtv_format, bool multisampled,
                           D3D12_RESOURCE_STATES resource_state)
    : m_tex12(texptr), m_resource_state(resource_state), m_multisampled(multisampled)
{
  D3D12_SRV_DIMENSION srv_dim12 =
      multisampled ? D3D12_SRV_DIMENSION_TEXTURE2DMSARRAY : D3D12_SRV_DIMENSION_TEXTURE2DARRAY;
  D3D12_DSV_DIMENSION dsv_dim12 =
      multisampled ? D3D12_DSV_DIMENSION_TEXTURE2DMSARRAY : D3D12_DSV_DIMENSION_TEXTURE2DARRAY;
  D3D12_RTV_DIMENSION rtv_dim12 =
      multisampled ? D3D12_RTV_DIMENSION_TEXTURE2DMSARRAY : D3D12_RTV_DIMENSION_TEXTURE2DARRAY;

  if (bind & TEXTURE_BIND_FLAG_SHADER_RESOURCE)
  {
    D3D12_SHADER_RESOURCE_VIEW_DESC srv_desc = {
        srv_format,  // DXGI_FORMAT Format
        srv_dim12    // D3D12_SRV_DIMENSION ViewDimension
    };

    if (srv_dim12 == D3D12_SRV_DIMENSION_TEXTURE2DARRAY)
    {
      srv_desc.Texture2DArray.MipLevels = -1;
      srv_desc.Texture2DArray.MostDetailedMip = 0;
      srv_desc.Texture2DArray.ResourceMinLODClamp = 0;
      srv_desc.Texture2DArray.ArraySize = -1;
    }
    else
    {
      srv_desc.Texture2DMSArray.ArraySize = -1;
    }

    srv_desc.Shader4ComponentMapping = D3D12_DEFAULT_SHADER_4_COMPONENT_MAPPING;

    CHECK(
        D3D::gpu_descriptor_heap_mgr->Allocate(&m_srv12_cpu, &m_srv12_gpu, &m_srv12_gpu_cpu_shadow),
        "Error: Ran out of permenant slots in GPU descriptor heap, but don't support rolling over "
        "heap.");

    D3D::device12->CreateShaderResourceView(m_tex12, &srv_desc, m_srv12_cpu);
    D3D::device12->CreateShaderResourceView(m_tex12, &srv_desc, m_srv12_gpu_cpu_shadow);
  }

  if (bind & TEXTURE_BIND_FLAG_DEPTH_STENCIL)
  {
    D3D12_DEPTH_STENCIL_VIEW_DESC dsv_desc = {
        dsv_format,          // DXGI_FORMAT Format
        dsv_dim12,           // D3D12_DSV_DIMENSION
        D3D12_DSV_FLAG_NONE  // D3D12_DSV_FLAG Flags
    };

    if (dsv_dim12 == D3D12_DSV_DIMENSION_TEXTURE2DARRAY)
      dsv_desc.Texture2DArray.ArraySize = -1;
    else
      dsv_desc.Texture2DMSArray.ArraySize = -1;

    D3D::dsv_descriptor_heap_mgr->Allocate(&m_dsv12);
    D3D::device12->CreateDepthStencilView(m_tex12, &dsv_desc, m_dsv12);
  }

  if (bind & TEXTURE_BIND_FLAG_RENDER_TARGET)
  {
    D3D12_RENDER_TARGET_VIEW_DESC rtv_desc = {
        rtv_format,  // DXGI_FORMAT Format
        rtv_dim12    // D3D12_RTV_DIMENSION ViewDimension
    };

    if (rtv_dim12 == D3D12_RTV_DIMENSION_TEXTURE2DARRAY)
      rtv_desc.Texture2DArray.ArraySize = -1;
    else
      rtv_desc.Texture2DMSArray.ArraySize = -1;

    D3D::rtv_descriptor_heap_mgr->Allocate(&m_rtv12);
    D3D::device12->CreateRenderTargetView(m_tex12, &rtv_desc, m_rtv12);
  }

  m_tex12->AddRef();
}

void D3DTexture2D::TransitionToResourceState(ID3D12GraphicsCommandList* command_list,
                                             D3D12_RESOURCE_STATES state_after)
{
  DX12::D3D::ResourceBarrier(command_list, m_tex12, m_resource_state, state_after,
                             D3D12_RESOURCE_BARRIER_ALL_SUBRESOURCES);
  m_resource_state = state_after;
}

D3DTexture2D::~D3DTexture2D()
{
  DX12::D3D::command_list_mgr->DestroyResourceAfterCurrentCommandListExecuted(m_tex12);
}

}  // namespace DX12
