/* SPDX-License-Identifier: GPL-2.0-or-later */

#include "BKE_mesh.h"

#include "BLI_task.hh"

#include "node_geometry_util.hh"

namespace blender::nodes::node_geo_mesh_topology_vertex_of_corner_cc {

static void node_declare(NodeDeclarationBuilder &b)
{
  b.add_input<decl::Int>(N_("Corner Index"))
      .implicit_field(implicit_field_inputs::index)
      .description(
          N_("The corner to retrieve data from. Defaults to the corner from the context"));
  b.add_output<decl::Int>(N_("Vertex Index"))
      .dependent_field()
      .description(N_("The vertex the corner is attached to"));
}

static int get_loop_vert(const MLoop &loop)
{
  return loop.v;
}

class CornerVertFieldInput final : public bke::MeshFieldInput {
 public:
  CornerVertFieldInput() : bke::MeshFieldInput(CPPType::get<int>(), "Corner Vertex")
  {
    category_ = Category::Generated;
  }

  GVArray get_varray_for_context(const Mesh &mesh,
                                 const eAttrDomain domain,
                                 const IndexMask /*mask*/) const final
  {
    if (domain != ATTR_DOMAIN_CORNER) {
      return {};
    }
    return VArray<int>::ForDerivedSpan<MLoop, get_loop_vert>(mesh.loops());
  }

  uint64_t hash() const final
  {
    return 30495867093876;
  }

  bool is_equal_to(const fn::FieldNode &other) const final
  {
    if (dynamic_cast<const CornerVertFieldInput *>(&other)) {
      return true;
    }
    return false;
  }
};

static void node_geo_exec(GeoNodeExecParams params)
{
  params.set_output("Vertex Index",
                    Field<int>(std::make_shared<FieldAtIndexInput>(
                        params.extract_input<Field<int>>("Corner Index"),
                        Field<int>(std::make_shared<CornerVertFieldInput>()),
                        ATTR_DOMAIN_CORNER)));
}

}  // namespace blender::nodes::node_geo_mesh_topology_vertex_of_corner_cc

void register_node_type_geo_mesh_topology_vertex_of_corner()
{
  namespace file_ns = blender::nodes::node_geo_mesh_topology_vertex_of_corner_cc;

  static bNodeType ntype;
  geo_node_type_base(
      &ntype, GEO_NODE_MESH_TOPOLOGY_VERTEX_OF_CORNER, "Vertex of Corner", NODE_CLASS_INPUT);
  ntype.geometry_node_execute = file_ns::node_geo_exec;
  ntype.declare = file_ns::node_declare;
  nodeRegisterType(&ntype);
}