#include "Runtime/Graphics/Shaders/CModelShaders.hpp"

#include "Runtime/CStopwatch.hpp"
#include "Runtime/Graphics/CLight.hpp"

#include <hecl/Backend.hpp>
#include <hecl/Pipeline.hpp>

namespace urde {

std::unordered_map<uint64_t, CModelShaders::ShaderPipelines> CModelShaders::g_ShaderPipelines;

void CModelShaders::LightingUniform::ActivateLights(const std::vector<CLight>& lts) {
  ambient = zeus::skClear;
  size_t curLight = 0;

  for (const CLight& light : lts) {
    switch (light.GetType()) {
    case ELightType::LocalAmbient:
      ambient += light.GetColor();
      break;
    case ELightType::Point:
    case ELightType::Spot:
    case ELightType::Custom:
    case ELightType::Directional: {
      if (curLight >= lights.size()) {
        continue;
      }
      CModelShaders::Light& lightOut = lights[curLight++];
      lightOut.pos = CGraphics::g_CameraMatrix * light.GetPosition();
      lightOut.dir = CGraphics::g_CameraMatrix.basis * light.GetDirection();
      lightOut.dir.normalize();
      lightOut.color = light.GetColor();
      lightOut.linAtt[0] = light.GetAttenuationConstant();
      lightOut.linAtt[1] = light.GetAttenuationLinear();
      lightOut.linAtt[2] = light.GetAttenuationQuadratic();
      lightOut.angAtt[0] = light.GetAngleAttenuationConstant();
      lightOut.angAtt[1] = light.GetAngleAttenuationLinear();
      lightOut.angAtt[2] = light.GetAngleAttenuationQuadratic();

      if (light.GetType() == ELightType::Directional)
        lightOut.pos = (-lightOut.dir) * 1048576.f;
      break;
    }
    }
  }

  for (; curLight < lights.size(); ++curLight) {
    CModelShaders::Light& lightOut = lights[curLight];
    lightOut.pos = zeus::skZero3f;
    lightOut.dir = zeus::skDown;
    lightOut.color = zeus::skClear;
    lightOut.linAtt[0] = 1.f;
    lightOut.linAtt[1] = 0.f;
    lightOut.linAtt[2] = 0.f;
    lightOut.angAtt[0] = 1.f;
    lightOut.angAtt[1] = 0.f;
    lightOut.angAtt[2] = 0.f;
  }
}

using TexCoordSource = hecl::Backend::TexCoordSource;

constexpr std::array<hecl::Backend::TextureInfo, 1> ThermalTextures{{
    {TexCoordSource::Normal, 7, true},
}};

constexpr std::array<hecl::Backend::TextureInfo, 3> BallFadeTextures{{
    {TexCoordSource::Position, 0, false}, // ID tex
    {TexCoordSource::Position, 0, false}, // Sphere ramp
    {TexCoordSource::Position, 1, false}, // TXTR_BallFade
}};

constexpr std::array<hecl::Backend::TextureInfo, 1> WorldShadowTextures{{
    {TexCoordSource::Position, 7, false}, // Shadow tex
}};

constexpr std::array<hecl::Backend::TextureInfo, 2> DisintegrateTextures{{
    {TexCoordSource::Position, 0, false}, // Ashy tex
    {TexCoordSource::Position, 1, false}, // Ashy tex
}};

static std::array<hecl::Backend::ExtensionSlot, size_t(EExtendedShader::MAX)> g_ExtensionSlots{{
    /* Default solid shading */
    {},
    /* Normal lit shading */
    {0, nullptr, hecl::Backend::BlendFactor::Original, hecl::Backend::BlendFactor::Original,
     hecl::Backend::ZTest::Original, hecl::Backend::CullMode::Backface, false, false, true},
    /* Thermal model shading */
    {1, ThermalTextures.data(), hecl::Backend::BlendFactor::One, hecl::Backend::BlendFactor::One,
     hecl::Backend::ZTest::Original, hecl::Backend::CullMode::Backface, false, false, false, true},
    /* Thermal model shading without Z-test or Z-write */
    {1, ThermalTextures.data(), hecl::Backend::BlendFactor::One, hecl::Backend::BlendFactor::One,
     hecl::Backend::ZTest::None, hecl::Backend::CullMode::Backface, true, false, false, true},
    /* Thermal static shading */
    {0, nullptr, hecl::Backend::BlendFactor::SrcAlpha, hecl::Backend::BlendFactor::One,
     hecl::Backend::ZTest::Original, hecl::Backend::CullMode::Backface, false, false, false, true, false, false, true},
    /* Thermal static shading without Z-write */
    {0, nullptr, hecl::Backend::BlendFactor::SrcAlpha, hecl::Backend::BlendFactor::One,
       hecl::Backend::ZTest::Original, hecl::Backend::CullMode::Backface, true, false, false, true, false, false, false},
    /* Forced alpha shading */
    {0, nullptr, hecl::Backend::BlendFactor::SrcAlpha, hecl::Backend::BlendFactor::InvSrcAlpha,
     hecl::Backend::ZTest::Original, hecl::Backend::CullMode::Backface, false, false, true},
    /* Forced additive shading */
    {0, nullptr, hecl::Backend::BlendFactor::SrcAlpha, hecl::Backend::BlendFactor::One, hecl::Backend::ZTest::Original,
     hecl::Backend::CullMode::Backface, false, false, true},
    /* Solid color */
    {0, nullptr, hecl::Backend::BlendFactor::One, hecl::Backend::BlendFactor::Zero, hecl::Backend::ZTest::LEqual,
     hecl::Backend::CullMode::Backface, false, false, false},
    /* Solid color additive */
    {0, nullptr, hecl::Backend::BlendFactor::SrcAlpha, hecl::Backend::BlendFactor::One, hecl::Backend::ZTest::LEqual,
     hecl::Backend::CullMode::Backface, true, false, true},
    /* Alpha-only Solid color frontface cull, LEqual */
    {0, nullptr, hecl::Backend::BlendFactor::Zero, hecl::Backend::BlendFactor::One, hecl::Backend::ZTest::LEqual,
     hecl::Backend::CullMode::Frontface, false, true, false},
    /* Alpha-only Solid color frontface cull, Always, No Z-write */
    {0, nullptr, hecl::Backend::BlendFactor::Zero, hecl::Backend::BlendFactor::One, hecl::Backend::ZTest::None,
     hecl::Backend::CullMode::Frontface, true, true, false},
    /* Alpha-only Solid color backface cull, LEqual */
    {0, nullptr, hecl::Backend::BlendFactor::Zero, hecl::Backend::BlendFactor::One, hecl::Backend::ZTest::LEqual,
     hecl::Backend::CullMode::Backface, false, true, false},
    /* Alpha-only Solid color backface cull, Greater, No Z-write */
    {0, nullptr, hecl::Backend::BlendFactor::Zero, hecl::Backend::BlendFactor::One, hecl::Backend::ZTest::Greater,
     hecl::Backend::CullMode::Backface, true, true, false},
    /* MorphBall shadow shading */
    {3, BallFadeTextures.data(), hecl::Backend::BlendFactor::SrcAlpha, hecl::Backend::BlendFactor::InvSrcAlpha,
     hecl::Backend::ZTest::Equal, hecl::Backend::CullMode::Backface, false, false, true, false, true},
    /* World shadow shading (modified lighting) */
    {1, WorldShadowTextures.data(), hecl::Backend::BlendFactor::Original, hecl::Backend::BlendFactor::Original,
     hecl::Backend::ZTest::Original, hecl::Backend::CullMode::Backface, false, false, true},
    /* Forced alpha shading without culling */
    {0, nullptr, hecl::Backend::BlendFactor::SrcAlpha, hecl::Backend::BlendFactor::InvSrcAlpha,
     hecl::Backend::ZTest::Original, hecl::Backend::CullMode::None, false, false, true},
    /* Forced additive shading without culling */
    {0, nullptr, hecl::Backend::BlendFactor::SrcAlpha, hecl::Backend::BlendFactor::One, hecl::Backend::ZTest::Original,
     hecl::Backend::CullMode::None, false, false, true},
    /* Forced alpha shading without Z-write */
    {0, nullptr, hecl::Backend::BlendFactor::SrcAlpha, hecl::Backend::BlendFactor::InvSrcAlpha,
     hecl::Backend::ZTest::Original, hecl::Backend::CullMode::Original, true, false, true},
    /* Forced additive shading without Z-write */
    {0, nullptr, hecl::Backend::BlendFactor::SrcAlpha, hecl::Backend::BlendFactor::One, hecl::Backend::ZTest::Original,
     hecl::Backend::CullMode::Original, true, false, true},
    /* Forced alpha shading without culling or Z-write */
    {0, nullptr, hecl::Backend::BlendFactor::SrcAlpha, hecl::Backend::BlendFactor::InvSrcAlpha,
     hecl::Backend::ZTest::Original, hecl::Backend::CullMode::None, true, false, true},
    /* Forced additive shading without culling or Z-write */
    {0, nullptr, hecl::Backend::BlendFactor::SrcAlpha, hecl::Backend::BlendFactor::One, hecl::Backend::ZTest::Original,
     hecl::Backend::CullMode::None, true, false, true},
    /* Depth GEqual no Z-write */
    {0, nullptr, hecl::Backend::BlendFactor::SrcAlpha, hecl::Backend::BlendFactor::InvSrcAlpha,
     hecl::Backend::ZTest::GEqual, hecl::Backend::CullMode::Backface, true, false, true},
    /* Disintegration */
    {2, DisintegrateTextures.data(), hecl::Backend::BlendFactor::SrcAlpha, hecl::Backend::BlendFactor::InvSrcAlpha,
     hecl::Backend::ZTest::LEqual, hecl::Backend::CullMode::Original, false, false, true, false, false, true},
    /* Forced additive shading without culling or Z-write and greater depth test */
    {0, nullptr, hecl::Backend::BlendFactor::SrcAlpha, hecl::Backend::BlendFactor::One, hecl::Backend::ZTest::Greater,
     hecl::Backend::CullMode::None, true, false, true},
    /* Thermal cold shading */
    {0, nullptr, hecl::Backend::BlendFactor::Original, hecl::Backend::BlendFactor::Original,
     hecl::Backend::ZTest::Original, hecl::Backend::CullMode::Original, false, false, true, false, false, false, true},
    /* Normal lit shading with alpha */
    {0, nullptr, hecl::Backend::BlendFactor::Original, hecl::Backend::BlendFactor::Original,
     hecl::Backend::ZTest::Original, hecl::Backend::CullMode::Backface},
    /* Normal lit shading with alpha without Z-write or depth test */
    {0, nullptr, hecl::Backend::BlendFactor::Original, hecl::Backend::BlendFactor::Original,
     hecl::Backend::ZTest::None, hecl::Backend::CullMode::Backface, true},
    /* Normal lit shading with cube reflection */
    {0, nullptr, hecl::Backend::BlendFactor::Original, hecl::Backend::BlendFactor::Original,
     hecl::Backend::ZTest::Original, hecl::Backend::CullMode::Backface, false, false, true},
    /* Normal lit shading with cube reflection and world shadow */
    {1, WorldShadowTextures.data(), hecl::Backend::BlendFactor::Original, hecl::Backend::BlendFactor::Original,
     hecl::Backend::ZTest::Original, hecl::Backend::CullMode::Backface, false, false, true},
}};

constexpr std::array<const char*, size_t(EExtendedShader::MAX)> ShaderMacros{
    "URDE_LIGHTING",
    "URDE_LIGHTING",
    "URDE_THERMAL_MODEL",
    "URDE_THERMAL_MODEL",
    "URDE_THERMAL_STATIC",
    "URDE_THERMAL_STATIC",
    "URDE_LIGHTING",
    "URDE_LIGHTING",
    "URDE_SOLID",
    "URDE_SOLID",
    "URDE_SOLID",
    "URDE_SOLID",
    "URDE_SOLID",
    "URDE_SOLID",
    "URDE_MB_SHADOW",
    "URDE_LIGHTING_SHADOW",
    "URDE_LIGHTING",
    "URDE_LIGHTING",
    "URDE_LIGHTING",
    "URDE_LIGHTING",
    "URDE_LIGHTING",
    "URDE_LIGHTING",
    "URDE_LIGHTING",
    "URDE_DISINTEGRATE",
    "URDE_LIGHTING",
    "URDE_THERMAL_COLD",
    "URDE_LIGHTING",
    "URDE_LIGHTING",
    "URDE_LIGHTING_CUBE_REFLECTION",
    "URDE_LIGHTING_CUBE_REFLECTION_SHADOW",
};

void CModelShaders::Initialize() {
  for (size_t i = 0; i < g_ExtensionSlots.size(); i++) {
    g_ExtensionSlots[i].shaderMacro = ShaderMacros[i];
  }
}

void CModelShaders::Shutdown() { g_ShaderPipelines.clear(); }

CModelShaders::ShaderPipelines CModelShaders::BuildExtendedShader(const hecl::Backend::ShaderTag& tag,
                                                                  const Material& material) {
  auto search = g_ShaderPipelines.find(tag.val64());
  if (search != g_ShaderPipelines.cend())
    return search->second;

  ShaderPipelines& newPipelines = g_ShaderPipelines[tag.val64()];
  newPipelines = std::make_shared<ShaderPipelinesData>();
  CGraphics::CommitResources([&](boo::IGraphicsDataFactory::Context& ctx) {
    size_t idx = 0;
    for (const auto& ext : g_ExtensionSlots)
      (*newPipelines)[idx++] = hecl::conv->convert(ctx, Shader_CModelShaders(SModelShadersInfo(material, tag, ext)));
    return true;
  } BooTrace);
  return newPipelines;
}

} // namespace urde