// Copyright 2012 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.

#include "VideoBackends/D3D/PerfQuery.h"
#include "Common/CommonFuncs.h"
#include "Common/CommonTypes.h"
#include "Common/Logging/Log.h"
#include "VideoBackends/D3D/D3DBase.h"
#include "VideoCommon/RenderBase.h"

namespace DX11
{
PerfQuery::PerfQuery() : m_query_read_pos()
{
  for (ActiveQuery& entry : m_query_buffer)
  {
    D3D11_QUERY_DESC qdesc = CD3D11_QUERY_DESC(D3D11_QUERY_OCCLUSION, 0);
    D3D::device->CreateQuery(&qdesc, &entry.query);
  }

  ResetQuery();
}

PerfQuery::~PerfQuery()
{
  for (ActiveQuery& entry : m_query_buffer)
  {
    // TODO: EndQuery?
    entry.query->Release();
  }
}

void PerfQuery::EnableQuery(PerfQueryGroup type)
{
  // Is this sane?
  if (m_query_count > m_query_buffer.size() / 2)
    WeakFlush();

  if (m_query_buffer.size() == m_query_count)
  {
    // TODO
    FlushOne();
    ERROR_LOG(VIDEO, "Flushed query buffer early!");
  }

  // start query
  if (type == PQG_ZCOMP_ZCOMPLOC || type == PQG_ZCOMP)
  {
    auto& entry = m_query_buffer[(m_query_read_pos + m_query_count) % m_query_buffer.size()];

    D3D::context->Begin(entry.query);
    entry.query_type = type;

    ++m_query_count;
  }
}

void PerfQuery::DisableQuery(PerfQueryGroup type)
{
  // stop query
  if (type == PQG_ZCOMP_ZCOMPLOC || type == PQG_ZCOMP)
  {
    auto& entry = m_query_buffer[(m_query_read_pos + m_query_count + m_query_buffer.size() - 1) %
                                 m_query_buffer.size()];
    D3D::context->End(entry.query);
  }
}

void PerfQuery::ResetQuery()
{
  m_query_count = 0;
  std::fill_n(m_results, ArraySize(m_results), 0);
}

u32 PerfQuery::GetQueryResult(PerfQueryType type)
{
  u32 result = 0;

  if (type == PQ_ZCOMP_INPUT_ZCOMPLOC || type == PQ_ZCOMP_OUTPUT_ZCOMPLOC)
    result = m_results[PQG_ZCOMP_ZCOMPLOC];
  else if (type == PQ_ZCOMP_INPUT || type == PQ_ZCOMP_OUTPUT)
    result = m_results[PQG_ZCOMP];
  else if (type == PQ_BLEND_INPUT)
    result = m_results[PQG_ZCOMP] + m_results[PQG_ZCOMP_ZCOMPLOC];
  else if (type == PQ_EFB_COPY_CLOCKS)
    result = m_results[PQG_EFB_COPY_CLOCKS];

  return result / 4;
}

void PerfQuery::FlushOne()
{
  auto& entry = m_query_buffer[m_query_read_pos];

  UINT64 result = 0;
  HRESULT hr = S_FALSE;
  while (hr != S_OK)
  {
    // TODO: Might cause us to be stuck in an infinite loop!
    hr = D3D::context->GetData(entry.query, &result, sizeof(result), 0);
  }

  // NOTE: Reported pixel metrics should be referenced to native resolution
  m_results[entry.query_type] += (u32)(result * EFB_WIDTH / g_renderer->GetTargetWidth() *
                                       EFB_HEIGHT / g_renderer->GetTargetHeight());

  m_query_read_pos = (m_query_read_pos + 1) % m_query_buffer.size();
  --m_query_count;
}

// TODO: could selectively flush things, but I don't think that will do much
void PerfQuery::FlushResults()
{
  while (!IsFlushed())
    FlushOne();
}

void PerfQuery::WeakFlush()
{
  while (!IsFlushed())
  {
    auto& entry = m_query_buffer[m_query_read_pos];

    UINT64 result = 0;
    HRESULT hr =
        D3D::context->GetData(entry.query, &result, sizeof(result), D3D11_ASYNC_GETDATA_DONOTFLUSH);

    if (hr == S_OK)
    {
      // NOTE: Reported pixel metrics should be referenced to native resolution
      m_results[entry.query_type] += (u32)(result * EFB_WIDTH / g_renderer->GetTargetWidth() *
                                           EFB_HEIGHT / g_renderer->GetTargetHeight());

      m_query_read_pos = (m_query_read_pos + 1) % m_query_buffer.size();
      --m_query_count;
    }
    else
    {
      break;
    }
  }
}

bool PerfQuery::IsFlushed() const
{
  return 0 == m_query_count;
}

}  // namespace
