/**
 * Looking Glass
 * Copyright © 2017-2026 The Looking Glass Authors
 * https://looking-glass.io
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc., 59
 * Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include "capture/CFrameBufferResource.h"
#include "capture/CFrameProcessorUtil.h"
#include "d3d/CD3D12Device.h"
#include "transport/CFrameTransport.h"
#include "transport/CIVSHMEM.h"
#include "CDebug.h"

#include <cstring>

bool CFrameBufferResource::Init(CFrameTransport * transport,
  CD3D12Device * dx12, unsigned frameIndex, uint8_t * base, size_t size,
  const D3D12_RESOURCE_DESC * textureDesc)
{
  m_frameIndex = frameIndex;

  if (size > transport->GetMaxFrameSize())
  {
    DEBUG_ERROR("Frame size of %llu is too large to fit in shared ram",
      (unsigned long long)size);
    return false;
  }

  const bool         indirect = dx12->IsIndirectCopy();
  const ResourceType type     = textureDesc ?
    RESOURCE_TEXTURE : RESOURCE_BUFFER;

  D3D12_RESOURCE_DESC desc = {};
  if (textureDesc)
  {
    if (indirect || !dx12->CanUseIVSHMEMTexture())
      return false;
    desc = *textureDesc;
    if (desc.Dimension        != D3D12_RESOURCE_DIMENSION_TEXTURE2D ||
        !desc.Width                                                ||
        !desc.Height                                               ||
        desc.DepthOrArraySize != 1                                  ||
        desc.MipLevels        != 1                                  ||
        desc.SampleDesc.Count != 1                                  ||
        desc.SampleDesc.Quality                                     ||
        desc.Format           == DXGI_FORMAT_UNKNOWN                ||
        desc.Layout           != D3D12_TEXTURE_LAYOUT_ROW_MAJOR     ||
        desc.Flags            != D3D12_RESOURCE_FLAG_ALLOW_CROSS_ADAPTER)
      return false;
  }
  else
  {
    desc.Dimension          = D3D12_RESOURCE_DIMENSION_BUFFER;
    desc.Width              = size;
    desc.Height             = 1;
    desc.DepthOrArraySize   = 1;
    desc.MipLevels          = 1;
    desc.Format             = DXGI_FORMAT_UNKNOWN;
    desc.SampleDesc.Count   = 1;
    desc.SampleDesc.Quality = 0;
    desc.Layout             = D3D12_TEXTURE_LAYOUT_ROW_MAJOR;
    desc.Flags              = D3D12_RESOURCE_FLAG_NONE;
    if (!indirect)
    {
      desc.Alignment = D3D12_DEFAULT_RESOURCE_PLACEMENT_ALIGNMENT;
      desc.Flags     = D3D12_RESOURCE_FLAG_ALLOW_CROSS_ADAPTER;
    }
  }

  // Nothing to do if the resource already represents this allocation.
  if (m_base == base && m_type == type &&
      ((type == RESOURCE_BUFFER && m_size >= size) ||
       (type == RESOURCE_TEXTURE &&
        CFrameProcessorUtil::ResourceDescMatches(m_desc, desc))))
  {
    m_frameSize = size;
    return true;
  }

  Reset();

  HRESULT       hr;
  const WCHAR * resName;
  UINT64        allocationSize = size;

  if (indirect)
  {
    DEBUG_TRACE("Creating standard resource for %p", base);
    D3D12_HEAP_PROPERTIES heapProps = {};
    heapProps.Type                 = D3D12_HEAP_TYPE_READBACK;
    heapProps.CPUPageProperty      = D3D12_CPU_PAGE_PROPERTY_UNKNOWN;
    heapProps.MemoryPoolPreference = D3D12_MEMORY_POOL_UNKNOWN;
    heapProps.CreationNodeMask     = 1;
    heapProps.VisibleNodeMask      = 1;

    hr = dx12->GetDevice()->CreateCommittedResource(
      &heapProps,
      D3D12_HEAP_FLAG_NONE,
      &desc,
      D3D12_RESOURCE_STATE_COPY_DEST,
      NULL,
      IID_PPV_ARGS(&m_res)
    );
    resName = L"STAGING";

    if (SUCCEEDED(hr))
    {
      D3D12_RANGE range = {0, 0};
      hr = m_res->Map(0, &range, &m_map);
      if (FAILED(hr))
      {
        DEBUG_ERROR_HR(hr, "Failed to map the resource");
        return false;
      }
    }
  }
  else
  {
    const UINT64 heapOffset =
      (uintptr_t)base -
      (uintptr_t)transport->GetIVSHMEM().GetMem();
    const D3D12_RESOURCE_ALLOCATION_INFO allocation =
      dx12->GetDevice()->GetResourceAllocationInfo(0, 1, &desc);
    allocationSize = allocation.SizeInBytes;
    const D3D12_HEAP_DESC heapDesc = dx12->GetHeap()->GetDesc();
    if (!allocation.Alignment ||
        heapOffset % allocation.Alignment ||
        allocation.SizeInBytes > transport->GetMaxFrameSize() ||
        heapOffset > heapDesc.SizeInBytes ||
        allocation.SizeInBytes > heapDesc.SizeInBytes - heapOffset)
    {
      DEBUG_ERROR("IVSHMEM resource does not fit its framebuffer allocation");
      return false;
    }

    if (type == RESOURCE_TEXTURE)
    {
      D3D12_FEATURE_DATA_FORMAT_SUPPORT support = {};
      support.Format = desc.Format;
      hr = dx12->GetDevice()->CheckFeatureSupport(
        D3D12_FEATURE_FORMAT_SUPPORT, &support, sizeof(support));
      if (FAILED(hr) ||
          !(support.Support1 & D3D12_FORMAT_SUPPORT1_TEXTURE2D))
      {
        DEBUG_ERROR("IVSHMEM texture format is unsupported");
        return false;
      }
      DEBUG_TRACE("Creating IVSHMEM texture for %p", base);
      resName = L"IVSHMEM Texture";
    }
    else
    {
      DEBUG_TRACE("Creating IVSHMEM buffer for %p", base);
      resName = L"IVSHMEM";
    }

    hr = dx12->GetDevice()->CreatePlacedResource(
      dx12->GetHeap().Get(),
      heapOffset,
      &desc,
      D3D12_RESOURCE_STATE_COMMON,
      NULL,
      IID_PPV_ARGS(&m_res)
    );
  }

  if (FAILED(hr))
  {
    DEBUG_ERROR_HR(hr, "Failed to create the FrameBuffer ID3D12Resource");
    return false;
  }

  m_res->SetName(resName);

  m_base      = base;
  m_size      = type == RESOURCE_TEXTURE ?
    (size_t)allocationSize : size;
  m_frameSize = size;
  m_type      = type;
  m_desc      = desc;
  return true;
}

void CFrameBufferResource::Reset()
{
  if (m_map)
  {
    m_res->Unmap(0, NULL);
    m_map = NULL;
  }

  m_base              = nullptr;
  m_size              = 0;
  m_frameSize         = 0;
  m_type              = RESOURCE_NONE;
  m_desc              = {};
  m_fullCopy          = false;
  m_nbCopyDirtyRects  = 0;
  m_copyPitch         = 0;
  m_copyBytesPerPixel = 0;
  m_res.Reset();
}

void CFrameBufferResource::SetCopyDamage(const RECT dirtyRects[],
  unsigned nbDirtyRects, bool fullCopy, unsigned pitch,
  unsigned bytesPerPixel)
{
  m_fullCopy          = fullCopy;
  m_nbCopyDirtyRects  = fullCopy ? 0 : nbDirtyRects;
  m_copyPitch         = pitch;
  m_copyBytesPerPixel = bytesPerPixel;
  if (m_nbCopyDirtyRects)
    memcpy(m_copyDirtyRects, dirtyRects,
      m_nbCopyDirtyRects * sizeof(*m_copyDirtyRects));
}