#include "occ_libstl.h"

#include <cstring>
#include <StlMesh_Mesh.hxx>
#include <StlMesh_MeshTriangle.hxx>
#include <StlMesh_SequenceOfMeshTriangle.hxx>
#include <TColgp_SequenceOfXYZ.hxx>

namespace internal {

/* Common */

static StlMesh_Mesh* occMeshPtr(const Handle_StlMesh_Mesh& mesh)
{
  return mesh.operator->();
}

static void occmesh_add_triangle(void* cookie,
                                 uint32_t /*tri_id*/,
                                 const foug_stl_triangle_t* tri,
                                 void* /*dummy*/)
{
  StlMesh_Mesh* mesh = static_cast<StlMesh_Mesh*>(cookie);
  const int uId = mesh->AddOnlyNewVertex(tri->v1.x, tri->v1.y, tri->v1.z);
  const int vId = mesh->AddOnlyNewVertex(tri->v2.x, tri->v2.y, tri->v2.z);
  const int wId = mesh->AddOnlyNewVertex(tri->v3.x, tri->v3.y, tri->v3.z);
  mesh->AddTriangle(uId, vId, wId, tri->normal.x, tri->normal.y, tri->normal.z);
}

static void occmesh_get_triangle(const void* cookie,
                                 uint32_t tri_id,
                                 foug_stl_triangle_t* triangle)
{
  const foug_OccStlMeshDomain* meshCookie = static_cast<const foug_OccStlMeshDomain*>(cookie);
  const StlMesh_SequenceOfMeshTriangle& occTriangles = meshCookie->mesh->Triangles(meshCookie->domainId);
  const Handle_StlMesh_MeshTriangle& occTri = occTriangles.Value(tri_id + 1);
  Standard_Integer v1;
  Standard_Integer v2;
  Standard_Integer v3;
  Standard_Real xN;
  Standard_Real yN;
  Standard_Real zN;
  occTri->GetVertexAndOrientation(v1, v2, v3, xN, yN, zN);
  triangle->normal.x = float(xN);
  triangle->normal.y = float(yN);
  triangle->normal.z = float(zN);

  const TColgp_SequenceOfXYZ& vertices = meshCookie->mesh->Vertices(meshCookie->domainId);
  const gp_XYZ& coordsV1 = vertices.Value(v1);
  const gp_XYZ& coordsV2 = vertices.Value(v2);
  const gp_XYZ& coordsV3 = vertices.Value(v3);
  triangle->v1.x = float(coordsV1.X());
  triangle->v2.x = float(coordsV2.X());
  triangle->v3.x = float(coordsV3.X());

  triangle->v1.y = float(coordsV1.Y());
  triangle->v2.y = float(coordsV2.Y());
  triangle->v3.y = float(coordsV3.Y());

  triangle->v1.z = float(coordsV1.Z());
  triangle->v2.z = float(coordsV2.Z());
  triangle->v3.z = float(coordsV3.Z());
}

static void occmesh_add_domain(void* cookie, void* /*dummy*/)
{
  StlMesh_Mesh* mesh = static_cast<StlMesh_Mesh*>(cookie);
  mesh->AddDomain();
}

} // namespace internal

void foug_stla_geom_input_set_occmesh(foug_stla_geom_input_t* input, const Handle_StlMesh_Mesh &mesh)
{
  input->cookie = internal::occMeshPtr(mesh);
  input->begin_solid_func = (foug_stla_begin_solid_func_t)internal::occmesh_add_domain;
  input->process_triangle_func = (foug_stla_process_triangle_func_t)internal::occmesh_add_triangle;
  input->end_solid_func = NULL;
}

void foug_stla_geom_output_set_occmesh(foug_stla_geom_output_t *output,
                                       const foug_OccStlMeshDomain &meshCookie)
{
  output->cookie = &meshCookie;
  output->solid_name = NULL;
  output->triangle_count = meshCookie.mesh->NbTriangles(meshCookie.domainId);
  output->get_triangle_func = internal::occmesh_get_triangle;
}

void foug_stlb_geom_input_set_occmesh(foug_stlb_geom_input_t* input, const Handle_StlMesh_Mesh &mesh)
{
  input->cookie = internal::occMeshPtr(mesh);
  input->process_header_func = NULL;
  input->begin_triangles_func = (foug_stlb_begin_triangles_func_t)internal::occmesh_add_domain;
  input->process_triangle_func = (foug_stlb_process_triangle_func_t)internal::occmesh_add_triangle;
  input->end_triangles_func = NULL;
}

void foug_stlb_geom_output_set_occmesh(foug_stlb_geom_output_t* output,
                                       const foug_OccStlMeshDomain &meshCookie)
{
  static const char occMeshBinaryHeader[] = "Generated by libfougdatax, occmesh geometry";
  output->cookie = &meshCookie;
  output->header = reinterpret_cast<const uint8_t*>(occMeshBinaryHeader);
  output->triangle_count = meshCookie.mesh->NbTriangles(meshCookie.domainId);
  output->get_triangle_func = internal::occmesh_get_triangle;
}

foug_OccStlMeshDomain::foug_OccStlMeshDomain(const Handle_StlMesh_Mesh &stlMesh, int stlDomainId)
  : mesh(stlMesh),
    domainId(stlDomainId)
{
}