#include <cassert>

#include "ObjDecoder.hh"
#include "exceptions.hh"
#include "util.hh"

ObjDecoder::ObjDecoder(uint8_t const* base, size_t length)
  : iff_(base, length)
{
  auto& root = iff_.getRoot();
  if (!root.isForm())
    throw FormatException{"Root node not FORM"};

  auto& rootForm = dynamic_cast<IffFile::Form const&>(root);
  if (rootForm.getSubtype() != "REAL")
    throw FormatException{"Root form not REAL"};

  for (auto realIt = rootForm.childrenBegin();realIt != rootForm.childrenEnd();++realIt) {
    if (realIt->getType() == "INFO") {
      name_ = *realIt;
      printf("Name: \"%s\"\n", name_.c_str());
    } else if (realIt->isForm()) {
      auto& itForm = dynamic_cast<IffFile::Form const&>(*realIt);
      if (itForm.getSubtype() == "OBJT")
	parseOBJT_(itForm);
      else if (itForm.getSubtype() == "APPR")
	parseAPPR_(itForm);
      else
	throw FormatException{"Unknown FORM type " + itForm.getSubtype()};
    } else
      throw FormatException{"Unknown chunk type " + realIt->getType()};
  }
}

ObjDecoder::Triangles ObjDecoder::getTriangles(unsigned lvl) const
{
  Triangles ret;
  for (auto idx : detailLevels_.at(lvl)) {
    if (idx < triangles_.size())
      ret.push_back(triangles_[idx]);
  }

  return ret;
}

ObjDecoder::Quads ObjDecoder::getQuads(unsigned lvl) const
{
  Quads ret;
  for (auto idx : detailLevels_.at(lvl)) {
    if (idx >= triangles_.size())
      ret.push_back(quads_[idx-triangles_.size()]);
  }
  
  return ret;
}

void ObjDecoder::parseOBJT_(IffFile::Form const& form)
{
}

void ObjDecoder::parseAPPR_(IffFile::Form const& form)
{
  if (form.getChildCount() != 1)
    throw FormatException{"Unexpected child count in APPR"};

  auto& child = *form.childrenBegin();
  if (!child.isForm())
    throw FormatException{"APPR child not FORM"};

  auto& childForm = dynamic_cast<IffFile::Form const&>(child);
  if (childForm.getSubtype() != "POLY")
    throw FormatException{"APPR child form not POLY"};

  parsePOLY_(childForm);
}

void ObjDecoder::parsePOLY_(IffFile::Form const& form)
{
  for (auto it = form.childrenBegin();it != form.childrenEnd();++it) {
    if (it->getType() == "INFO") {
    } else if (it->getType() == "VERT") {
      if (it->getSize()%12 != 0)
	throw FormatException{"Unexpected VERT size"};
      for (size_t i = 0;i < it->getSize();i+=12) {
	std::array<int32_t, 3> vertex;
	for (size_t j = 0;j < 3;++j)
	  vertex[j] = readU32LE(it->begin()+i+j*4);
	//	printf("V: %d %d %d\n", vertex[0], vertex[1], vertex[2]);
	vertices_.push_back(vertex);
      }
    } else if (it->isForm()) {
      auto& itForm = dynamic_cast<IffFile::Form const&>(*it);
      if (itForm.getSubtype() == "TRIS") {
	parseTRIS_(itForm);
      } else if (itForm.getSubtype() == "QUAD") {
	parseQUAD_(itForm);
      } else if (itForm.getSubtype() == "DETA") {
	parseDETA_(itForm);
      } else if (itForm.getSubtype() == "TXMS") {
	parseTXMS_(itForm);
      } else if (itForm.getSubtype() == "GRUP") {
	// NYI
      } else
	throw FormatException{"Unknown POLY subform " + itForm.getSubtype()};
    } else if (it->getType() == "ATTR") {
      // NYI
    } else if (it->getType() == "XATR") {
      // NYI
    } else if (it->getType() == "SUPR") {
      // NYI
    } else
      throw FormatException{"Unknown POLY child " + it->getType()};
  }
}

void ObjDecoder::parseTRIS_(IffFile::Form const& form)
{
  if (form.getChildCount() != 2)
    throw FormatException{"Unexpected child count in TRIS"};

  auto vertCount = vertices_.size();
  printf("VC: %lu\n", vertCount);
  
  IffFile::Object const *face = nullptr, *maps = nullptr;
  for (auto it = form.childrenBegin();it != form.childrenEnd();++it) {
    if (it->getType() == "FACE") {
      if (face)
	throw FormatException{"Multiple FACE in TRIS"};
      face = &*it;
    } else if (it->getType() == "MAPS") {
      if (maps)
	throw FormatException{"Multiple MAPS in TRIS"};
      maps = &*it;
    } else
      throw FormatException{"Unknown TRIS child " + it->getType()};
  }

  assert(face && maps);

  if (face->getSize()%8 != 0)
    throw FormatException{"Unexpected FACE size"};
  auto numTriangles = face->getSize()/8;
  if (maps->getSize() != numTriangles*16)
    printf("WARNING: Unexpected MAPS size\n");
     //   throw FormatException{"Unexpected MAPS size"};

  for (unsigned i = 0;i < numTriangles;++i) {  
    Triangle tri;
    for (unsigned j = 0;j < 3;++j)
      tri.vertIdx[j] = readU16LE(face->begin()+i*8+2+j*2);
    tri.id = readU16LE(maps->begin()+i*16);
    tri.tex = readU16LE(maps->begin()+i*16+2);
    for (unsigned j = 0;j < 3;++j) {
      tri.texCoords[j][0] = readU16LE(maps->begin()+i*16+4+j*4);
      tri.texCoords[j][1] = readU16LE(maps->begin()+i*16+4+j*4+2);
    }
    // printf("T%u: (%hu (%hu %hu)), (%hu (%hu %hu)), (%hu (%hu %hu))\n", tri.id,
    // 	   tri.vertIdx[0], tri.texCoords[0][0], tri.texCoords[0][1],
    // 	   tri.vertIdx[1], tri.texCoords[1][0], tri.texCoords[1][1],
    // 	   tri.vertIdx[2], tri.texCoords[2][0], tri.texCoords[2][1]);
    triangles_.push_back(tri);
  }

  printf("TC: %lu\n", triangles_.size());
}

void ObjDecoder::parseQUAD_(IffFile::Form const& form)
{
  if (form.getChildCount() != 2)
    throw FormatException{"Unexpected child count in QUAD"};

  IffFile::Object const *face = nullptr, *maps = nullptr;
  for (auto it = form.childrenBegin();it != form.childrenEnd();++it) {
    if (it->getType() == "FACE") {
      if (face)
	throw FormatException{"Multiple FACE in QUAD"};
      face = &*it;
    } else if (it->getType() == "MAPS") {
      if (maps)
	throw FormatException{"Multiple MAPS in QUAD"};
      maps = &*it;
    } else
      throw FormatException{"Unknown TRIS child " + it->getType()};
  }

  assert(face && maps);

  if (face->getSize()%10 != 0)
    throw FormatException{"Unexpected FACE size"};
  auto numQuads = face->getSize()/10;
  if (maps->getSize() != numQuads*20)
    printf("WARNING: Unexpected MAPS size\n");
  //throw FormatException{"Unexpected MAPS size"};

  for (unsigned i = 0;i < numQuads;++i) {    
    Quad quad;
    for (unsigned j = 0;j < 4;++j)
      quad.vertIdx[j] = readU16LE(face->begin()+i*10+2+j*2);
    quad.id = readU16LE(maps->begin()+i*20);
    quad.tex = readU16LE(maps->begin()+i*20+2);
    for (unsigned j = 0;j < 4;++j) {
      quad.texCoords[j][0] = readU16LE(maps->begin()+i*20+4+j*4);
      quad.texCoords[j][1] = readU16LE(maps->begin()+i*20+4+j*4+2);
    }
    // printf("Q%u: (%hu (%hu %hu)), (%hu (%hu %hu)), (%hu (%hu %hu)), (%hu (%hu %hu))\n", quad.id,
    // 	   quad.vertIdx[0], quad.texCoords[0][0], quad.texCoords[0][1],
    // 	   quad.vertIdx[1], quad.texCoords[1][0], quad.texCoords[1][1],
    // 	   quad.vertIdx[2], quad.texCoords[2][0], quad.texCoords[2][1],
    // 	   quad.vertIdx[3], quad.texCoords[3][0], quad.texCoords[3][1]);
    quads_.push_back(quad);
  }

  printf("QC: %lu\n", quads_.size());
}

void ObjDecoder::parseDETA_(IffFile::Form const& form)
{
  if (form.getChildCount() < 1)
    throw FormatException{"Unexpected child count in DETA"};

  unsigned lvl = 0;
  for (auto it = form.childrenBegin();it != form.childrenEnd();++it) {
    if (it->getType().substr(0, 3) != "LVL")
      throw FormatException{"Unexpected child " + it->getType() + " in DETA"};
    if (std::stoi(it->getType().substr(3)) != lvl)
      throw FormatException{"Unexpected detail level"};

    if (it->getSize() < 4)
      throw FormatException{"DETA child too small"};
    
    // uint32_t unkown = readU32LE(it->begin());
    detailLevels_.emplace_back();
    for (size_t pos = 4;pos < it->getSize()-1;pos += 2)
      detailLevels_.back().push_back(readU16LE(it->begin()+pos));

    printf("LVL %u: %lu entries\n", lvl, detailLevels_.back().size());
    ++lvl;
  }
}

void ObjDecoder::parseTXMS_(IffFile::Form const& form)
{
  if ((textures_.size() != 0) || texAnims_.size() != 0)
    throw FormatException{"Multiple TXMS"};
  
  if (form.getChildCount() < 1)
    throw FormatException{"Unexpected child count in TXMS"};

  auto it = form.childrenBegin();
  auto& info = *it++;
  if (info.getType() != "INFO")
    throw FormatException{"Missing INFO in TXMS"};
  if (info.getSize() != 4)
    throw FormatException{"Unexpected INFO size in TXMS"};
  
  uint16_t numTXMP, numTXMA;
  numTXMP = readU16LE(info.begin());
  numTXMA = readU16LE(info.begin()+2);
  if (form.getChildCount() != 1u+numTXMP+numTXMA)
    throw FormatException{"Unexpected child count in TXMS"};
  
  textures_.reserve(numTXMP);
  texAnims_.reserve(numTXMA);
  for (;it != form.childrenEnd();++it) {
    if (it->getType() == "TXMP") {
      if (it->getSize() < 12u)
	throw FormatException{"TXMP smaller than header"};
      
      Texture tex;
      if (it->begin()[7] == '\0')
	tex.name = std::string(reinterpret_cast<char const*>(it->begin()));
      else
	tex.name = std::string(reinterpret_cast<char const*>(it->begin()), 8);
      printf("TXMP name \"%s\"\n", tex.name.c_str());

      tex.width = readU16LE(it->begin()+8);
      tex.height = readU16LE(it->begin()+10);
      printf("TXMP size %hux%hu\n", tex.width, tex.height);
      
      if (it->getSize() < 12u+tex.width*tex.height)
	throw FormatException{"TXMP too small for pixel data"};
      tex.pixels = std::vector<uint8_t>(it->begin()+12, it->begin()+12+tex.width*tex.height);
      textures_.emplace_back(std::move(tex));
    } else if (it->getType() == "TXMA") {
      if (it->getSize() < 14u)
	throw FormatException{"TXMA smaller than header"};
      
      TextureAnimation tex;
      if (it->begin()[7] == '\0')
	tex.name = std::string(reinterpret_cast<char const*>(it->begin()));
      else
	tex.name = std::string(reinterpret_cast<char const*>(it->begin()), 8);
      printf("TXMA name \"%s\"\n", tex.name.c_str());

      tex.width = readU16LE(it->begin()+8);
      tex.height = readU16LE(it->begin()+10);
      tex.frames = readU16LE(it->begin()+12);
      printf("TXMA size %hux%hu, %hu frames\n", tex.width, tex.height, tex.frames);

      if (it->getSize() < 14u+tex.width*tex.height*tex.frames)
	throw FormatException{"TXMA too small for pixel data"};

      tex.pixels.reserve(tex.frames);
      uint8_t const* pos = it->begin()+14;
      for (unsigned i = 0;i < tex.frames;++i) {
	tex.pixels.emplace_back(pos, pos+tex.width*tex.height);
	pos += tex.width*tex.height;
      }

      texAnims_.emplace_back(std::move(tex));
    } else
      throw FormatException{"Unkown TXMS child " + it->getType()};
  }
}