#include "CFluidPlaneGPU.hpp"

namespace urde {

CFluidPlaneGPU::CFluidPlaneGPU(CAssetId texPattern1, CAssetId texPattern2, CAssetId texColor, CAssetId bumpMap,
                               CAssetId envMap, CAssetId envBumpMap, CAssetId lightMap, float unitsPerLightmapTexel,
                               float tileSize, u32 tileSubdivisions, EFluidType fluidType, float alpha,
                               const zeus::CVector3f& bumpLightDir, float bumpScale, const CFluidUVMotion& mot,
                               float turbSpeed, float turbDistance, float turbFreqMax, float turbFreqMin,
                               float turbPhaseMax, float turbPhaseMin, float turbAmplitudeMax, float turbAmplitudeMin,
                               float specularMin, float specularMax, float reflectionBlend, float reflectionSize,
                               float rippleIntensity, u32 maxVertCount)
: CFluidPlaneCPU(texPattern1, texPattern2, texColor, bumpMap, envMap, envBumpMap, lightMap, unitsPerLightmapTexel,
                 tileSize, tileSubdivisions, fluidType, alpha, bumpLightDir, bumpScale, mot, turbSpeed, turbDistance,
                 turbFreqMax, turbFreqMin, turbPhaseMax, turbPhaseMin, turbAmplitudeMax, turbAmplitudeMin, specularMin,
                 specularMax, reflectionBlend, reflectionSize, rippleIntensity, maxVertCount) {
  m_tessellation = true;
}

void CFluidPlaneGPU::RenderStripWithRipples(float curY, const CFluidPlaneRender::SHFieldSample (&heights)[46][46],
                                            const u8 (&flags)[9][9], int startYDiv,
                                            const CFluidPlaneRender::SPatchInfo& info,
                                            std::vector<CFluidPlaneShader::Vertex>& vOut,
                                            std::vector<CFluidPlaneShader::PatchVertex>& pvOut) const {
  m_shader->bindTessellation();

  int yTile = (startYDiv + CFluidPlaneRender::numSubdivisionsInTile - 1) / CFluidPlaneRender::numSubdivisionsInTile;
  int endXTile =
      (info.x0_xSubdivs + CFluidPlaneRender::numSubdivisionsInTile - 4) / CFluidPlaneRender::numSubdivisionsInTile;

  float yMin = curY;
  float subdivF = CFluidPlaneRender::numSubdivisionsInTile;

  float curX = info.x4_localMin.x();
  int gridCell = info.x28_tileX + info.x2a_gridDimX * (info.x2e_tileY + yTile - 1);
  int xTile = 1;
  int tileSpan;
  for (int i = 1; i < info.x0_xSubdivs - 2; i += CFluidPlaneRender::numSubdivisionsInTile * tileSpan,
           gridCell += tileSpan, xTile += tileSpan, curX += info.x14_tileSize * tileSpan) {
    tileSpan = 1;
    if (info.x30_gridFlags && !info.x30_gridFlags[gridCell])
      continue;

    CFluidPlaneShader::PatchVertex pv;
    size_t start = pvOut.size();

    if ((flags[yTile][xTile] & 0x1f) == 0x1f) {
      for (; xTile + tileSpan <= endXTile; ++tileSpan) {
        if ((flags[yTile][xTile + tileSpan] & 0x1f) != 0x1f)
          break;
        if (info.x30_gridFlags && !info.x30_gridFlags[gridCell + tileSpan])
          break;
      }

      std::fill(std::begin(pv.m_outerLevels), std::end(pv.m_outerLevels), subdivF);
      std::fill(std::begin(pv.m_innerLevels), std::end(pv.m_innerLevels), subdivF);
    } else {
      bool r19 = (flags[yTile + 1][xTile] & 0x2) != 0; // North
      bool r16 = (flags[yTile][xTile - 1] & 0x8) != 0; // West
      bool r18 = (flags[yTile][xTile + 1] & 0x4) != 0; // East
      bool r17 = (flags[yTile - 1][xTile] & 0x1) != 0; // South

      pv.m_outerLevels[0] = r16 ? subdivF : 1.f;
      pv.m_outerLevels[1] = r17 ? subdivF : 1.f;
      pv.m_outerLevels[2] = r18 ? subdivF : 1.f;
      pv.m_outerLevels[3] = r19 ? subdivF : 1.f;
      std::fill(std::begin(pv.m_innerLevels), std::end(pv.m_innerLevels), subdivF);
    }

    float curTileY = yMin;
    float curTileX = curX;
    for (int t = 0; t < tileSpan; ++t) {
      pv.m_pos = zeus::CVector4f(curTileX, curTileY, curTileX + info.x14_tileSize, curTileY + info.x14_tileSize);
      pvOut.push_back(pv);
      curTileX += info.x14_tileSize;
    }

    CGraphics::DrawArray(start, pvOut.size() - start);
  }
}

} // namespace urde