/* SPDX-License-Identifier: GPL-2.0-or-later
 * Copyright 2008 Blender Foundation. All rights reserved. */

/** \file
 * \ingroup bke
 */

#include <string.h>

#include "DNA_mesh_types.h"
#include "DNA_object_types.h"

#include "BLI_listbase.h"
#include "BLI_string.h"
#include "BLI_string_utils.h"
#include "BLI_utildefines.h"

#include "BKE_customdata.h"
#include "BKE_editmesh.h"
#include "BKE_object.h"
#include "BKE_object_deform.h"
#include "BKE_object_facemap.h" /* own include */

#include "BLT_translation.h"

#include "MEM_guardedalloc.h"

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

static bool fmap_unique_check(void *arg, const char *name)
{
  struct {
    Object *ob;
    void *fm;
  } *data = arg;

  bFaceMap *fmap;

  for (fmap = data->ob->fmaps.first; fmap; fmap = fmap->next) {
    if (data->fm != fmap) {
      if (STREQ(fmap->name, name)) {
        return true;
      }
    }
  }

  return false;
}

static bFaceMap *fmap_duplicate(bFaceMap *infmap)
{
  bFaceMap *outfmap;

  if (!infmap) {
    return NULL;
  }

  outfmap = MEM_callocN(sizeof(bFaceMap), "copy facemap");

  /* For now, just copy everything over. */
  memcpy(outfmap, infmap, sizeof(bFaceMap));

  outfmap->next = outfmap->prev = NULL;

  return outfmap;
}

void BKE_object_facemap_copy_list(ListBase *outbase, const ListBase *inbase)
{
  bFaceMap *fmap, *fmapn;

  BLI_listbase_clear(outbase);

  for (fmap = inbase->first; fmap; fmap = fmap->next) {
    fmapn = fmap_duplicate(fmap);
    BLI_addtail(outbase, fmapn);
  }
}

void BKE_object_facemap_unique_name(Object *ob, bFaceMap *fmap)
{
  struct {
    Object *ob;
    void *fmap;
  } data;
  data.ob = ob;
  data.fmap = fmap;

  BLI_uniquename_cb(fmap_unique_check, &data, DATA_("Group"), '.', fmap->name, sizeof(fmap->name));
}

bFaceMap *BKE_object_facemap_add_name(Object *ob, const char *name)
{
  bFaceMap *fmap;

  if (!ob || ob->type != OB_MESH) {
    return NULL;
  }

  fmap = MEM_callocN(sizeof(bFaceMap), __func__);

  BLI_strncpy(fmap->name, name, sizeof(fmap->name));

  BLI_addtail(&ob->fmaps, fmap);

  ob->actfmap = BLI_listbase_count(&ob->fmaps);

  BKE_object_facemap_unique_name(ob, fmap);

  return fmap;
}

bFaceMap *BKE_object_facemap_add(Object *ob)
{
  return BKE_object_facemap_add_name(ob, DATA_("FaceMap"));
}

static void object_fmap_remove_edit_mode(Object *ob, bFaceMap *fmap, bool do_selected, bool purge)
{
  const int fmap_nr = BLI_findindex(&ob->fmaps, fmap);

  if (ob->type == OB_MESH) {
    Mesh *me = ob->data;

    if (me->edit_mesh) {
      BMEditMesh *em = me->edit_mesh;
      const int cd_fmap_offset = CustomData_get_offset(&em->bm->pdata, CD_FACEMAP);

      if (cd_fmap_offset != -1) {
        BMFace *efa;
        BMIter iter;
        int *map;

        if (purge) {
          BM_ITER_MESH (efa, &iter, em->bm, BM_FACES_OF_MESH) {
            map = BM_ELEM_CD_GET_VOID_P(efa, cd_fmap_offset);

            if (map) {
              if (*map == fmap_nr) {
                *map = -1;
              }
              else if (*map > fmap_nr) {
                *map -= 1;
              }
            }
          }
        }
        else {
          BM_ITER_MESH (efa, &iter, em->bm, BM_FACES_OF_MESH) {
            map = BM_ELEM_CD_GET_VOID_P(efa, cd_fmap_offset);

            if (map && *map == fmap_nr &&
                (!do_selected || BM_elem_flag_test(efa, BM_ELEM_SELECT))) {
              *map = -1;
            }
          }
        }
      }

      if (ob->actfmap == BLI_listbase_count(&ob->fmaps)) {
        ob->actfmap--;
      }

      BLI_remlink(&ob->fmaps, fmap);
      MEM_freeN(fmap);
    }
  }
}

static void object_fmap_remove_object_mode(Object *ob, bFaceMap *fmap, bool purge)
{
  const int fmap_nr = BLI_findindex(&ob->fmaps, fmap);

  if (ob->type == OB_MESH) {
    Mesh *me = ob->data;

    if (CustomData_has_layer(&me->pdata, CD_FACEMAP)) {
      int *map = CustomData_get_layer(&me->pdata, CD_FACEMAP);
      int i;

      if (map) {
        for (i = 0; i < me->totpoly; i++) {
          if (map[i] == fmap_nr) {
            map[i] = -1;
          }
          else if (purge && map[i] > fmap_nr) {
            map[i]--;
          }
        }
      }
    }

    if (ob->actfmap == BLI_listbase_count(&ob->fmaps)) {
      ob->actfmap--;
    }

    BLI_remlink(&ob->fmaps, fmap);
    MEM_freeN(fmap);
  }
}

static void fmap_remove_exec(Object *ob, bFaceMap *fmap, const bool is_edit_mode, const bool purge)
{
  if (is_edit_mode) {
    object_fmap_remove_edit_mode(ob, fmap, false, purge);
  }
  else {
    object_fmap_remove_object_mode(ob, fmap, purge);
  }
}

void BKE_object_facemap_remove(Object *ob, bFaceMap *fmap)
{
  fmap_remove_exec(ob, fmap, BKE_object_is_in_editmode(ob), true);
}

void BKE_object_facemap_clear(Object *ob)
{
  bFaceMap *fmap = (bFaceMap *)ob->fmaps.first;

  if (fmap) {
    const bool edit_mode = BKE_object_is_in_editmode_vgroup(ob);

    while (fmap) {
      bFaceMap *next_fmap = fmap->next;
      fmap_remove_exec(ob, fmap, edit_mode, false);
      fmap = next_fmap;
    }
  }
  /* remove all face-maps */
  if (ob->type == OB_MESH) {
    Mesh *me = ob->data;
    CustomData_free_layer(&me->pdata, CD_FACEMAP, me->totpoly, 0);
  }
  ob->actfmap = 0;
}

int BKE_object_facemap_name_index(Object *ob, const char *name)
{
  return (name) ? BLI_findstringindex(&ob->fmaps, name, offsetof(bFaceMap, name)) : -1;
}

bFaceMap *BKE_object_facemap_find_name(Object *ob, const char *name)
{
  return BLI_findstring(&ob->fmaps, name, offsetof(bFaceMap, name));
}

int *BKE_object_facemap_index_map_create(Object *ob_src, Object *ob_dst, int *r_map_len)
{
  /* Build src to merged mapping of facemap indices. */
  if (BLI_listbase_is_empty(&ob_src->fmaps) || BLI_listbase_is_empty(&ob_dst->fmaps)) {
    *r_map_len = 0;
    return NULL;
  }

  *r_map_len = BLI_listbase_count(&ob_src->fmaps);
  int *fmap_index_map = MEM_malloc_arrayN(
      *r_map_len, sizeof(*fmap_index_map), "defgroup index map create");
  bool is_fmap_remap_needed = false;

  int i = 0;
  for (bFaceMap *fmap_src = ob_src->fmaps.first; fmap_src; fmap_src = fmap_src->next, i++) {
    fmap_index_map[i] = BKE_object_facemap_name_index(ob_dst, fmap_src->name);
    is_fmap_remap_needed = is_fmap_remap_needed || (fmap_index_map[i] != i);
  }

  if (!is_fmap_remap_needed) {
    MEM_freeN(fmap_index_map);
    fmap_index_map = NULL;
    *r_map_len = 0;
  }

  return fmap_index_map;
}

void BKE_object_facemap_index_map_apply(int *fmap, int fmap_len, const int *map, int map_len)
{
  if (map == NULL || map_len == 0) {
    return;
  }
  for (int i = 0; i < fmap_len; i++, fmap++) {
    *fmap = (*fmap < map_len && *fmap != -1) ? map[*fmap] : -1;
  }
}