// Copyright 2014 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.

#include <algorithm>
#include <array>

#include "Common/BitSet.h"
#include "Common/CommonTypes.h"
#include "Common/Logging/Log.h"
#include "Common/MsgHandler.h"

#include "VideoBackends/D3D/D3DBase.h"
#include "VideoBackends/D3D/D3DState.h"
#include "VideoCommon/VideoConfig.h"

namespace DX11
{
namespace D3D
{
StateManager* stateman;

StateManager::StateManager() = default;
StateManager::~StateManager() = default;

void StateManager::Apply()
{
  if (!m_dirtyFlags)
    return;

  int textureMaskShift = LeastSignificantSetBit((u32)DirtyFlag_Texture0);
  int samplerMaskShift = LeastSignificantSetBit((u32)DirtyFlag_Sampler0);

  u32 dirtyTextures =
      (m_dirtyFlags &
       (DirtyFlag_Texture0 | DirtyFlag_Texture1 | DirtyFlag_Texture2 | DirtyFlag_Texture3 |
        DirtyFlag_Texture4 | DirtyFlag_Texture5 | DirtyFlag_Texture6 | DirtyFlag_Texture7)) >>
      textureMaskShift;
  u32 dirtySamplers =
      (m_dirtyFlags &
       (DirtyFlag_Sampler0 | DirtyFlag_Sampler1 | DirtyFlag_Sampler2 | DirtyFlag_Sampler3 |
        DirtyFlag_Sampler4 | DirtyFlag_Sampler5 | DirtyFlag_Sampler6 | DirtyFlag_Sampler7)) >>
      samplerMaskShift;
  u32 dirtyConstants = m_dirtyFlags & (DirtyFlag_PixelConstants | DirtyFlag_VertexConstants |
                                       DirtyFlag_GeometryConstants);
  u32 dirtyShaders =
      m_dirtyFlags & (DirtyFlag_PixelShader | DirtyFlag_VertexShader | DirtyFlag_GeometryShader);
  u32 dirtyBuffers = m_dirtyFlags & (DirtyFlag_VertexBuffer | DirtyFlag_IndexBuffer);

  if (dirtyConstants)
  {
    if (m_current.pixelConstants[0] != m_pending.pixelConstants[0] ||
        m_current.pixelConstants[1] != m_pending.pixelConstants[1])
    {
      D3D::context->PSSetConstantBuffers(0, m_pending.pixelConstants[1] ? 2 : 1,
                                         m_pending.pixelConstants.data());
      m_current.pixelConstants[0] = m_pending.pixelConstants[0];
      m_current.pixelConstants[1] = m_pending.pixelConstants[1];
    }

    if (m_current.vertexConstants != m_pending.vertexConstants)
    {
      D3D::context->VSSetConstantBuffers(0, 1, &m_pending.vertexConstants);
      m_current.vertexConstants = m_pending.vertexConstants;
    }

    if (m_current.geometryConstants != m_pending.geometryConstants)
    {
      D3D::context->GSSetConstantBuffers(0, 1, &m_pending.geometryConstants);
      m_current.geometryConstants = m_pending.geometryConstants;
    }
  }

  if (dirtyBuffers || (m_dirtyFlags & DirtyFlag_InputAssembler))
  {
    if (m_current.vertexBuffer != m_pending.vertexBuffer ||
        m_current.vertexBufferStride != m_pending.vertexBufferStride ||
        m_current.vertexBufferOffset != m_pending.vertexBufferOffset)
    {
      D3D::context->IASetVertexBuffers(0, 1, &m_pending.vertexBuffer, &m_pending.vertexBufferStride,
                                       &m_pending.vertexBufferOffset);
      m_current.vertexBuffer = m_pending.vertexBuffer;
      m_current.vertexBufferStride = m_pending.vertexBufferStride;
      m_current.vertexBufferOffset = m_pending.vertexBufferOffset;
    }

    if (m_current.indexBuffer != m_pending.indexBuffer)
    {
      D3D::context->IASetIndexBuffer(m_pending.indexBuffer, DXGI_FORMAT_R16_UINT, 0);
      m_current.indexBuffer = m_pending.indexBuffer;
    }

    if (m_current.topology != m_pending.topology)
    {
      D3D::context->IASetPrimitiveTopology(m_pending.topology);
      m_current.topology = m_pending.topology;
    }

    if (m_current.inputLayout != m_pending.inputLayout)
    {
      D3D::context->IASetInputLayout(m_pending.inputLayout);
      m_current.inputLayout = m_pending.inputLayout;
    }
  }

  while (dirtyTextures)
  {
    int index = LeastSignificantSetBit(dirtyTextures);
    if (m_current.textures[index] != m_pending.textures[index])
    {
      D3D::context->PSSetShaderResources(index, 1, &m_pending.textures[index]);
      m_current.textures[index] = m_pending.textures[index];
    }

    dirtyTextures &= ~(1 << index);
  }

  while (dirtySamplers)
  {
    int index = LeastSignificantSetBit(dirtySamplers);
    if (m_current.samplers[index] != m_pending.samplers[index])
    {
      D3D::context->PSSetSamplers(index, 1, &m_pending.samplers[index]);
      m_current.samplers[index] = m_pending.samplers[index];
    }

    dirtySamplers &= ~(1 << index);
  }

  if (dirtyShaders)
  {
    if (m_current.pixelShader != m_pending.pixelShader)
    {
      D3D::context->PSSetShader(m_pending.pixelShader, nullptr, 0);
      m_current.pixelShader = m_pending.pixelShader;
    }

    if (m_current.vertexShader != m_pending.vertexShader)
    {
      D3D::context->VSSetShader(m_pending.vertexShader, nullptr, 0);
      m_current.vertexShader = m_pending.vertexShader;
    }

    if (m_current.geometryShader != m_pending.geometryShader)
    {
      D3D::context->GSSetShader(m_pending.geometryShader, nullptr, 0);
      m_current.geometryShader = m_pending.geometryShader;
    }
  }

  if (m_dirtyFlags & DirtyFlag_BlendState)
  {
    D3D::context->OMSetBlendState(m_pending.blendState, nullptr, 0xFFFFFFFF);
    m_current.blendState = m_pending.blendState;
  }
  if (m_dirtyFlags & DirtyFlag_DepthState)
  {
    D3D::context->OMSetDepthStencilState(m_pending.depthState, 0);
    m_current.depthState = m_pending.depthState;
  }
  if (m_dirtyFlags & DirtyFlag_RasterizerState)
  {
    D3D::context->RSSetState(m_pending.rasterizerState);
    m_current.rasterizerState = m_pending.rasterizerState;
  }

  m_dirtyFlags = 0;
}

u32 StateManager::UnsetTexture(ID3D11ShaderResourceView* srv)
{
  u32 mask = 0;

  for (u32 index = 0; index < 8; ++index)
  {
    if (m_current.textures[index] == srv)
    {
      SetTexture(index, nullptr);
      mask |= 1 << index;
    }
  }

  return mask;
}

void StateManager::SetTextureByMask(u32 textureSlotMask, ID3D11ShaderResourceView* srv)
{
  while (textureSlotMask)
  {
    int index = LeastSignificantSetBit(textureSlotMask);
    SetTexture(index, srv);
    textureSlotMask &= ~(1 << index);
  }
}

}  // namespace D3D

StateCache::~StateCache()
{
  for (auto& it : m_depth)
    SAFE_RELEASE(it.second);

  for (auto& it : m_raster)
    SAFE_RELEASE(it.second);

  for (auto& it : m_blend)
    SAFE_RELEASE(it.second);

  for (auto& it : m_sampler)
    SAFE_RELEASE(it.second);
}

ID3D11SamplerState* StateCache::Get(SamplerState state)
{
  auto it = m_sampler.find(state.hex);
  if (it != m_sampler.end())
    return it->second;

  D3D11_SAMPLER_DESC sampdc = CD3D11_SAMPLER_DESC(CD3D11_DEFAULT());
  if (state.mipmap_filter == SamplerState::Filter::Linear)
  {
    if (state.min_filter == SamplerState::Filter::Linear)
      sampdc.Filter = (state.mag_filter == SamplerState::Filter::Linear) ?
                          D3D11_FILTER_MIN_MAG_MIP_LINEAR :
                          D3D11_FILTER_MIN_LINEAR_MAG_POINT_MIP_LINEAR;
    else
      sampdc.Filter = (state.mag_filter == SamplerState::Filter::Linear) ?
                          D3D11_FILTER_MIN_POINT_MAG_MIP_LINEAR :
                          D3D11_FILTER_MIN_MAG_POINT_MIP_LINEAR;
  }
  else
  {
    if (state.min_filter == SamplerState::Filter::Linear)
      sampdc.Filter = (state.mag_filter == SamplerState::Filter::Linear) ?
                          D3D11_FILTER_MIN_MAG_LINEAR_MIP_POINT :
                          D3D11_FILTER_MIN_LINEAR_MAG_MIP_POINT;
    else
      sampdc.Filter = (state.mag_filter == SamplerState::Filter::Linear) ?
                          D3D11_FILTER_MIN_POINT_MAG_LINEAR_MIP_POINT :
                          D3D11_FILTER_MIN_MAG_MIP_POINT;
  }

  static constexpr std::array<D3D11_TEXTURE_ADDRESS_MODE, 3> address_modes = {
      {D3D11_TEXTURE_ADDRESS_CLAMP, D3D11_TEXTURE_ADDRESS_WRAP, D3D11_TEXTURE_ADDRESS_MIRROR}};
  sampdc.AddressU = address_modes[static_cast<u32>(state.wrap_u.Value())];
  sampdc.AddressV = address_modes[static_cast<u32>(state.wrap_v.Value())];
  sampdc.MaxLOD = state.max_lod / 16.f;
  sampdc.MinLOD = state.min_lod / 16.f;
  sampdc.MipLODBias = (s32)state.lod_bias / 256.f;

  if (state.anisotropic_filtering)
  {
    sampdc.Filter = D3D11_FILTER_ANISOTROPIC;
    sampdc.MaxAnisotropy = 1u << g_ActiveConfig.iMaxAnisotropy;
  }

  ID3D11SamplerState* res = nullptr;
  HRESULT hr = D3D::device->CreateSamplerState(&sampdc, &res);
  if (FAILED(hr))
    PanicAlert("Fail %s %d\n", __FILE__, __LINE__);

  D3D::SetDebugObjectName(res, "sampler state used to emulate the GX pipeline");
  m_sampler.emplace(state.hex, res);
  return res;
}

ID3D11BlendState* StateCache::Get(BlendingState state)
{
  auto it = m_blend.find(state.hex);
  if (it != m_blend.end())
    return it->second;

  if (state.logicopenable && D3D::device1)
  {
    D3D11_BLEND_DESC1 desc = {};
    D3D11_RENDER_TARGET_BLEND_DESC1& tdesc = desc.RenderTarget[0];
    if (state.colorupdate)
      tdesc.RenderTargetWriteMask = D3D11_COLOR_WRITE_ENABLE_RED | D3D11_COLOR_WRITE_ENABLE_GREEN |
                                    D3D11_COLOR_WRITE_ENABLE_BLUE;
    else
      tdesc.RenderTargetWriteMask = 0;
    if (state.alphaupdate)
      tdesc.RenderTargetWriteMask |= D3D11_COLOR_WRITE_ENABLE_ALPHA;

    static constexpr std::array<D3D11_LOGIC_OP, 16> logic_ops = {
        {D3D11_LOGIC_OP_CLEAR, D3D11_LOGIC_OP_AND, D3D11_LOGIC_OP_AND_REVERSE, D3D11_LOGIC_OP_COPY,
         D3D11_LOGIC_OP_AND_INVERTED, D3D11_LOGIC_OP_NOOP, D3D11_LOGIC_OP_XOR, D3D11_LOGIC_OP_OR,
         D3D11_LOGIC_OP_NOR, D3D11_LOGIC_OP_EQUIV, D3D11_LOGIC_OP_INVERT, D3D11_LOGIC_OP_OR_REVERSE,
         D3D11_LOGIC_OP_COPY_INVERTED, D3D11_LOGIC_OP_OR_INVERTED, D3D11_LOGIC_OP_NAND,
         D3D11_LOGIC_OP_SET}};
    tdesc.LogicOpEnable = TRUE;
    tdesc.LogicOp = logic_ops[state.logicmode];

    ID3D11BlendState1* res;
    HRESULT hr = D3D::device1->CreateBlendState1(&desc, &res);
    if (SUCCEEDED(hr))
    {
      D3D::SetDebugObjectName(res, "blend state used to emulate the GX pipeline");
      m_blend.emplace(state.hex, res);
      return res;
    }
  }

  D3D11_BLEND_DESC desc = {};
  desc.AlphaToCoverageEnable = FALSE;
  desc.IndependentBlendEnable = FALSE;

  D3D11_RENDER_TARGET_BLEND_DESC& tdesc = desc.RenderTarget[0];
  tdesc.BlendEnable = state.blendenable;

  if (state.colorupdate)
    tdesc.RenderTargetWriteMask = D3D11_COLOR_WRITE_ENABLE_RED | D3D11_COLOR_WRITE_ENABLE_GREEN |
                                  D3D11_COLOR_WRITE_ENABLE_BLUE;
  else
    tdesc.RenderTargetWriteMask = 0;
  if (state.alphaupdate)
    tdesc.RenderTargetWriteMask |= D3D11_COLOR_WRITE_ENABLE_ALPHA;

  const bool use_dual_source = state.usedualsrc;
  const std::array<D3D11_BLEND, 8> src_factors = {
      {D3D11_BLEND_ZERO, D3D11_BLEND_ONE, D3D11_BLEND_DEST_COLOR, D3D11_BLEND_INV_DEST_COLOR,
       use_dual_source ? D3D11_BLEND_SRC1_ALPHA : D3D11_BLEND_SRC_ALPHA,
       use_dual_source ? D3D11_BLEND_INV_SRC1_ALPHA : D3D11_BLEND_INV_SRC_ALPHA,
       D3D11_BLEND_DEST_ALPHA, D3D11_BLEND_INV_DEST_ALPHA}};
  const std::array<D3D11_BLEND, 8> dst_factors = {
      {D3D11_BLEND_ZERO, D3D11_BLEND_ONE, D3D11_BLEND_SRC_COLOR, D3D11_BLEND_INV_SRC_COLOR,
       use_dual_source ? D3D11_BLEND_SRC1_ALPHA : D3D11_BLEND_SRC_ALPHA,
       use_dual_source ? D3D11_BLEND_INV_SRC1_ALPHA : D3D11_BLEND_INV_SRC_ALPHA,
       D3D11_BLEND_DEST_ALPHA, D3D11_BLEND_INV_DEST_ALPHA}};

  tdesc.SrcBlend = src_factors[state.srcfactor];
  tdesc.SrcBlendAlpha = src_factors[state.srcfactoralpha];
  tdesc.DestBlend = dst_factors[state.dstfactor];
  tdesc.DestBlendAlpha = dst_factors[state.dstfactoralpha];
  tdesc.BlendOp = state.subtract ? D3D11_BLEND_OP_REV_SUBTRACT : D3D11_BLEND_OP_ADD;
  tdesc.BlendOpAlpha = state.subtractAlpha ? D3D11_BLEND_OP_REV_SUBTRACT : D3D11_BLEND_OP_ADD;

  ID3D11BlendState* res = nullptr;

  HRESULT hr = D3D::device->CreateBlendState(&desc, &res);
  if (FAILED(hr))
    PanicAlert("Failed to create blend state at %s %d\n", __FILE__, __LINE__);

  D3D::SetDebugObjectName(res, "blend state used to emulate the GX pipeline");
  m_blend.emplace(state.hex, res);
  return res;
}

ID3D11RasterizerState* StateCache::Get(RasterizationState state)
{
  auto it = m_raster.find(state.hex);
  if (it != m_raster.end())
    return it->second;

  static constexpr std::array<D3D11_CULL_MODE, 4> cull_modes = {
      {D3D11_CULL_NONE, D3D11_CULL_BACK, D3D11_CULL_FRONT, D3D11_CULL_BACK}};

  D3D11_RASTERIZER_DESC desc = {};
  desc.FillMode = D3D11_FILL_SOLID;
  desc.CullMode = cull_modes[state.cullmode];
  desc.ScissorEnable = TRUE;

  ID3D11RasterizerState* res = nullptr;
  HRESULT hr = D3D::device->CreateRasterizerState(&desc, &res);
  if (FAILED(hr))
    PanicAlert("Failed to create rasterizer state at %s %d\n", __FILE__, __LINE__);

  D3D::SetDebugObjectName(res, "rasterizer state used to emulate the GX pipeline");
  m_raster.emplace(state.hex, res);
  return res;
}

ID3D11DepthStencilState* StateCache::Get(DepthState state)
{
  auto it = m_depth.find(state.hex);
  if (it != m_depth.end())
    return it->second;

  D3D11_DEPTH_STENCIL_DESC depthdc = CD3D11_DEPTH_STENCIL_DESC(CD3D11_DEFAULT());

  depthdc.DepthEnable = TRUE;
  depthdc.DepthWriteMask = D3D11_DEPTH_WRITE_MASK_ALL;
  depthdc.DepthFunc = D3D11_COMPARISON_GREATER;
  depthdc.StencilEnable = FALSE;
  depthdc.StencilReadMask = D3D11_DEFAULT_STENCIL_READ_MASK;
  depthdc.StencilWriteMask = D3D11_DEFAULT_STENCIL_WRITE_MASK;

  // Less/greater are swapped due to inverted depth.
  const D3D11_COMPARISON_FUNC d3dCmpFuncs[8] = {
      D3D11_COMPARISON_NEVER,         D3D11_COMPARISON_GREATER, D3D11_COMPARISON_EQUAL,
      D3D11_COMPARISON_GREATER_EQUAL, D3D11_COMPARISON_LESS,    D3D11_COMPARISON_NOT_EQUAL,
      D3D11_COMPARISON_LESS_EQUAL,    D3D11_COMPARISON_ALWAYS};

  if (state.testenable)
  {
    depthdc.DepthEnable = TRUE;
    depthdc.DepthWriteMask =
        state.updateenable ? D3D11_DEPTH_WRITE_MASK_ALL : D3D11_DEPTH_WRITE_MASK_ZERO;
    depthdc.DepthFunc = d3dCmpFuncs[state.func];
  }
  else
  {
    // if the test is disabled write is disabled too
    depthdc.DepthEnable = FALSE;
    depthdc.DepthWriteMask = D3D11_DEPTH_WRITE_MASK_ZERO;
  }

  ID3D11DepthStencilState* res = nullptr;

  HRESULT hr = D3D::device->CreateDepthStencilState(&depthdc, &res);
  if (SUCCEEDED(hr))
    D3D::SetDebugObjectName(res, "depth-stencil state used to emulate the GX pipeline");
  else
    PanicAlert("Failed to create depth state at %s %d\n", __FILE__, __LINE__);

  m_depth.emplace(state.hex, res);

  return res;
}

D3D11_PRIMITIVE_TOPOLOGY StateCache::GetPrimitiveTopology(PrimitiveType primitive)
{
  static constexpr std::array<D3D11_PRIMITIVE_TOPOLOGY, 4> primitives = {
      {D3D11_PRIMITIVE_TOPOLOGY_POINTLIST, D3D11_PRIMITIVE_TOPOLOGY_LINELIST,
       D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST, D3D11_PRIMITIVE_TOPOLOGY_TRIANGLESTRIP}};
  return primitives[static_cast<u32>(primitive)];
}

}  // namespace DX11