/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2019 by Blender Foundation
 * All rights reserved.
 */

/** \file
 * \ingroup edobj
 */

#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <float.h>
#include <ctype.h>

#include "MEM_guardedalloc.h"

#include "BLI_blenlib.h"
#include "BLI_math.h"
#include "BLI_utildefines.h"

#include "DNA_scene_types.h"
#include "DNA_object_types.h"
#include "DNA_meshdata_types.h"
#include "DNA_mesh_types.h"

#include "BKE_context.h"
#include "BKE_global.h"
#include "BKE_main.h"
#include "BKE_mesh.h"
#include "BKE_object.h"
#include "BKE_paint.h"
#include "BKE_report.h"
#include "BKE_scene.h"
#include "BKE_customdata.h"
#include "BKE_mesh_remesh_voxel.h"

#include "DEG_depsgraph.h"
#include "DEG_depsgraph_build.h"

#include "ED_mesh.h"
#include "ED_object.h"
#include "ED_screen.h"
#include "ED_sculpt.h"
#include "ED_undo.h"

#include "RNA_access.h"
#include "RNA_define.h"
#include "RNA_enum_types.h"

#include "WM_api.h"
#include "WM_types.h"
#include "WM_message.h"
#include "WM_toolsystem.h"

#include "object_intern.h"  // own include

static bool object_remesh_poll(bContext *C)
{
  Object *ob = CTX_data_active_object(C);

  if (BKE_object_is_in_editmode(ob)) {
    CTX_wm_operator_poll_msg_set(C, "The voxel remesher cannot run from edit mode.");
    return false;
  }

  if (ob->mode == OB_MODE_SCULPT && ob->sculpt->bm) {
    CTX_wm_operator_poll_msg_set(C, "The voxel remesher cannot run with dyntopo activated.");
  }

  return ED_operator_object_active_editable_mesh(C);
}

static int voxel_remesh_exec(bContext *C, wmOperator *op)
{
  Object *ob = CTX_data_active_object(C);
  Main *bmain = CTX_data_main(C);

  Mesh *mesh = ob->data;
  Mesh *new_mesh;

  if (mesh->remesh_voxel_size <= 0.0f) {
    BKE_report(op->reports, RPT_ERROR, "Voxel remesher cannot run with a voxel size of 0.0.");
    return OPERATOR_CANCELLED;
  }

  if (ob->mode == OB_MODE_SCULPT) {
    ED_sculpt_undo_geometry_begin(ob);
  }

  new_mesh = BKE_mesh_remesh_voxel_to_mesh_nomain(mesh, mesh->remesh_voxel_size);

  if (!new_mesh) {
    return OPERATOR_CANCELLED;
  }

  Mesh *obj_mesh_copy = NULL;
  if (mesh->flag & ME_REMESH_REPROJECT_PAINT_MASK) {
    obj_mesh_copy = BKE_mesh_new_nomain_from_template(mesh, mesh->totvert, 0, 0, 0, 0);
    CustomData_copy(
        &mesh->vdata, &obj_mesh_copy->vdata, CD_MASK_MESH.vmask, CD_DUPLICATE, mesh->totvert);
    for (int i = 0; i < mesh->totvert; i++) {
      copy_v3_v3(obj_mesh_copy->mvert[i].co, mesh->mvert[i].co);
    }
  }

  BKE_mesh_nomain_to_mesh(new_mesh, mesh, ob, &CD_MASK_MESH, true);

  if (mesh->flag & ME_REMESH_REPROJECT_PAINT_MASK) {
    BKE_remesh_reproject_paint_mask(mesh, obj_mesh_copy);
    BKE_mesh_free(obj_mesh_copy);
  }

  if (mesh->flag & ME_REMESH_SMOOTH_NORMALS) {
    BKE_mesh_smooth_flag_set(ob->data, true);
  }

  if (ob->mode == OB_MODE_SCULPT) {
    ED_sculpt_undo_geometry_end(ob);
  }

  BKE_mesh_batch_cache_dirty_tag(ob->data, BKE_MESH_BATCH_DIRTY_ALL);
  DEG_relations_tag_update(bmain);
  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
  WM_event_add_notifier(C, NC_GEOM | ND_DATA, ob->data);

  return OPERATOR_FINISHED;
}

void OBJECT_OT_voxel_remesh(wmOperatorType *ot)
{
  /* identifiers */
  ot->name = "Voxel Remesh";
  ot->description =
      "Calculates a new manifold mesh based on the volume of the current mesh. All data layers "
      "will be lost";
  ot->idname = "OBJECT_OT_voxel_remesh";

  /* api callbacks */
  ot->poll = object_remesh_poll;
  ot->exec = voxel_remesh_exec;

  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
}