/* SPDX-License-Identifier: GPL-2.0-or-later
 * Copyright 2018 Blender Foundation. All rights reserved. */

/** \file
 * \ingroup bke
 */

#include "BKE_mesh.h"
#include "BKE_subdiv_ccg.h"

#include "MEM_guardedalloc.h"

#include "DNA_mesh_types.h"
#include "DNA_meshdata_types.h"

typedef struct CCGMaterialFromMeshData {
  const Mesh *mesh;
  const MPoly *polys;
  const int *material_indices;
} CCGMaterialFromMeshData;

static DMFlagMat subdiv_ccg_material_flags_eval(
    SubdivCCGMaterialFlagsEvaluator *material_flags_evaluator, const int coarse_face_index)
{
  CCGMaterialFromMeshData *data = (CCGMaterialFromMeshData *)material_flags_evaluator->user_data;
  BLI_assert(coarse_face_index < data->mesh->totpoly);
  const MPoly *poly = &data->polys[coarse_face_index];
  DMFlagMat material_flags;
  material_flags.flag = poly->flag;
  material_flags.mat_nr = data->material_indices ? data->material_indices[coarse_face_index] : 0;
  return material_flags;
}

static void subdiv_ccg_material_flags_free(
    SubdivCCGMaterialFlagsEvaluator *material_flags_evaluator)
{
  MEM_freeN(material_flags_evaluator->user_data);
}

void BKE_subdiv_ccg_material_flags_init_from_mesh(
    SubdivCCGMaterialFlagsEvaluator *material_flags_evaluator, const Mesh *mesh)
{
  CCGMaterialFromMeshData *data = MEM_mallocN(sizeof(CCGMaterialFromMeshData),
                                              "ccg material eval");
  data->mesh = mesh;
  data->material_indices = (const int *)CustomData_get_layer_named(
      &mesh->pdata, CD_PROP_INT32, "material_index");
  data->polys = BKE_mesh_polys(mesh);
  material_flags_evaluator->eval_material_flags = subdiv_ccg_material_flags_eval;
  material_flags_evaluator->free = subdiv_ccg_material_flags_free;
  material_flags_evaluator->user_data = data;
}