/*
 * 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) Blender Foundation
 * All rights reserved.
 */

/** \file
 * \ingroup modifiers
 */

#include "BLI_utildefines.h"

#include "BLI_math.h"
#include "BLI_math_inline.h"
#include "BLI_task.h"

#include "BLT_translation.h"

#include "DNA_customdata_types.h"
#include "DNA_mesh_types.h"
#include "DNA_meshdata_types.h"
#include "DNA_modifier_types.h"
#include "DNA_object_types.h"
#include "DNA_scene_types.h"
#include "DNA_screen_types.h"

#include "BKE_context.h"
#include "BKE_lib_id.h"
#include "BKE_mesh.h"
#include "BKE_modifier.h"
#include "BKE_ocean.h"
#include "BKE_screen.h"

#include "UI_interface.h"
#include "UI_resources.h"

#include "RNA_access.h"

#include "BLO_read_write.h"

#include "WM_types.h" /* For UI free bake operator. */

#include "DEG_depsgraph_query.h"

#include "MOD_modifiertypes.h"
#include "MOD_ui_common.h"

#ifdef WITH_OCEANSIM
static void init_cache_data(Object *ob, struct OceanModifierData *omd, const int resolution)
{
  const char *relbase = BKE_modifier_path_relbase_from_global(ob);

  omd->oceancache = BKE_ocean_init_cache(omd->cachepath,
                                         relbase,
                                         omd->bakestart,
                                         omd->bakeend,
                                         omd->wave_scale,
                                         omd->chop_amount,
                                         omd->foam_coverage,
                                         omd->foam_fade,
                                         resolution);
}

static void simulate_ocean_modifier(struct OceanModifierData *omd)
{
  BKE_ocean_simulate(omd->ocean, omd->time, omd->wave_scale, omd->chop_amount);
}
#endif /* WITH_OCEANSIM */

/* Modifier Code */

static void initData(ModifierData *md)
{
#ifdef WITH_OCEANSIM
  OceanModifierData *omd = (OceanModifierData *)md;

  /* Render resolution */
  omd->resolution = 7;
  /* Display resolution for the non-render case */
  omd->viewport_resolution = 7;

  omd->spatial_size = 50;

  omd->wave_alignment = 0.0;
  omd->wind_velocity = 30.0;

  omd->damp = 0.5;
  omd->smallest_wave = 0.01;
  omd->wave_direction = 0.0;
  omd->depth = 200.0;

  omd->wave_scale = 1.0;

  omd->chop_amount = 1.0;

  omd->foam_coverage = 0.0;

  omd->seed = 0;
  omd->time = 1.0;

  omd->spectrum = MOD_OCEAN_SPECTRUM_PHILLIPS;
  omd->sharpen_peak_jonswap = 0.0f;
  omd->fetch_jonswap = 120.0f;

  omd->size = 1.0;
  omd->repeat_x = 1;
  omd->repeat_y = 1;

  BKE_modifier_path_init(omd->cachepath, sizeof(omd->cachepath), "cache_ocean");

  omd->cached = 0;
  omd->bakestart = 1;
  omd->bakeend = 250;
  omd->oceancache = NULL;
  omd->foam_fade = 0.98;
  omd->foamlayername[0] = '\0';  /* layer name empty by default */
  omd->spraylayername[0] = '\0'; /* layer name empty by default */

  omd->ocean = BKE_ocean_add();
  BKE_ocean_init_from_modifier(omd->ocean, omd, omd->viewport_resolution);
  simulate_ocean_modifier(omd);
#else  /* WITH_OCEANSIM */
  /* unused */
  (void)md;
#endif /* WITH_OCEANSIM */
}

static void freeData(ModifierData *md)
{
#ifdef WITH_OCEANSIM
  OceanModifierData *omd = (OceanModifierData *)md;

  BKE_ocean_free(omd->ocean);
  if (omd->oceancache) {
    BKE_ocean_free_cache(omd->oceancache);
  }
#else  /* WITH_OCEANSIM */
  /* unused */
  (void)md;
#endif /* WITH_OCEANSIM */
}

static void copyData(const ModifierData *md, ModifierData *target, const int flag)
{
#ifdef WITH_OCEANSIM
#  if 0
  const OceanModifierData *omd = (const OceanModifierData *)md;
#  endif
  OceanModifierData *tomd = (OceanModifierData *)target;

  BKE_modifier_copydata_generic(md, target, flag);

  /* The oceancache object will be recreated for this copy
   * automatically when cached=true */
  tomd->oceancache = NULL;

  tomd->ocean = BKE_ocean_add();
  BKE_ocean_init_from_modifier(tomd->ocean, tomd, tomd->viewport_resolution);
  simulate_ocean_modifier(tomd);
#else  /* WITH_OCEANSIM */
  /* unused */
  (void)md;
  (void)target;
  (void)flag;
#endif /* WITH_OCEANSIM */
}

#ifdef WITH_OCEANSIM
static void requiredDataMask(Object *UNUSED(ob),
                             ModifierData *md,
                             CustomData_MeshMasks *r_cddata_masks)
{
  OceanModifierData *omd = (OceanModifierData *)md;

  if (omd->flag & MOD_OCEAN_GENERATE_FOAM) {
    r_cddata_masks->fmask |= CD_MASK_MCOL; /* XXX Should be loop cddata I guess? */
  }
}
#else  /* WITH_OCEANSIM */
static void requiredDataMask(Object *UNUSED(ob),
                             ModifierData *UNUSED(md),
                             CustomData_MeshMasks *UNUSED(r_cddata_masks))
{
}
#endif /* WITH_OCEANSIM */

static bool dependsOnNormals(ModifierData *md)
{
  OceanModifierData *omd = (OceanModifierData *)md;
  return (omd->geometry_mode != MOD_OCEAN_GEOM_GENERATE);
}

#ifdef WITH_OCEANSIM

typedef struct GenerateOceanGeometryData {
  MVert *mverts;
  MPoly *mpolys;
  MLoop *mloops;
  MLoopUV *mloopuvs;

  int res_x, res_y;
  int rx, ry;
  float ox, oy;
  float sx, sy;
  float ix, iy;
} GenerateOceanGeometryData;

static void generate_ocean_geometry_vertices(void *__restrict userdata,
                                             const int y,
                                             const TaskParallelTLS *__restrict UNUSED(tls))
{
  GenerateOceanGeometryData *gogd = userdata;
  int x;

  for (x = 0; x <= gogd->res_x; x++) {
    const int i = y * (gogd->res_x + 1) + x;
    float *co = gogd->mverts[i].co;
    co[0] = gogd->ox + (x * gogd->sx);
    co[1] = gogd->oy + (y * gogd->sy);
    co[2] = 0.0f;
  }
}

static void generate_ocean_geometry_polygons(void *__restrict userdata,
                                             const int y,
                                             const TaskParallelTLS *__restrict UNUSED(tls))
{
  GenerateOceanGeometryData *gogd = userdata;
  int x;

  for (x = 0; x < gogd->res_x; x++) {
    const int fi = y * gogd->res_x + x;
    const int vi = y * (gogd->res_x + 1) + x;
    MPoly *mp = &gogd->mpolys[fi];
    MLoop *ml = &gogd->mloops[fi * 4];

    ml->v = vi;
    ml++;
    ml->v = vi + 1;
    ml++;
    ml->v = vi + 1 + gogd->res_x + 1;
    ml++;
    ml->v = vi + gogd->res_x + 1;
    ml++;

    mp->loopstart = fi * 4;
    mp->totloop = 4;

    mp->flag |= ME_SMOOTH;
  }
}

static void generate_ocean_geometry_uvs(void *__restrict userdata,
                                        const int y,
                                        const TaskParallelTLS *__restrict UNUSED(tls))
{
  GenerateOceanGeometryData *gogd = userdata;
  int x;

  for (x = 0; x < gogd->res_x; x++) {
    const int i = y * gogd->res_x + x;
    MLoopUV *luv = &gogd->mloopuvs[i * 4];

    luv->uv[0] = x * gogd->ix;
    luv->uv[1] = y * gogd->iy;
    luv++;

    luv->uv[0] = (x + 1) * gogd->ix;
    luv->uv[1] = y * gogd->iy;
    luv++;

    luv->uv[0] = (x + 1) * gogd->ix;
    luv->uv[1] = (y + 1) * gogd->iy;
    luv++;

    luv->uv[0] = x * gogd->ix;
    luv->uv[1] = (y + 1) * gogd->iy;
    luv++;
  }
}

static Mesh *generate_ocean_geometry(OceanModifierData *omd, Mesh *mesh_orig, const int resolution)
{
  Mesh *result;

  GenerateOceanGeometryData gogd;

  int num_verts;
  int num_polys;

  const bool use_threading = resolution > 4;

  gogd.rx = resolution * resolution;
  gogd.ry = resolution * resolution;
  gogd.res_x = gogd.rx * omd->repeat_x;
  gogd.res_y = gogd.ry * omd->repeat_y;

  num_verts = (gogd.res_x + 1) * (gogd.res_y + 1);
  num_polys = gogd.res_x * gogd.res_y;

  gogd.sx = omd->size * omd->spatial_size;
  gogd.sy = omd->size * omd->spatial_size;
  gogd.ox = -gogd.sx / 2.0f;
  gogd.oy = -gogd.sy / 2.0f;

  gogd.sx /= gogd.rx;
  gogd.sy /= gogd.ry;

  result = BKE_mesh_new_nomain(num_verts, 0, 0, num_polys * 4, num_polys);
  BKE_mesh_copy_settings(result, mesh_orig);

  gogd.mverts = result->mvert;
  gogd.mpolys = result->mpoly;
  gogd.mloops = result->mloop;

  TaskParallelSettings settings;
  BLI_parallel_range_settings_defaults(&settings);
  settings.use_threading = use_threading;

  /* create vertices */
  BLI_task_parallel_range(0, gogd.res_y + 1, &gogd, generate_ocean_geometry_vertices, &settings);

  /* create faces */
  BLI_task_parallel_range(0, gogd.res_y, &gogd, generate_ocean_geometry_polygons, &settings);

  BKE_mesh_calc_edges(result, false, false);

  /* add uvs */
  if (CustomData_number_of_layers(&result->ldata, CD_MLOOPUV) < MAX_MTFACE) {
    gogd.mloopuvs = CustomData_add_layer(
        &result->ldata, CD_MLOOPUV, CD_CALLOC, NULL, num_polys * 4);

    if (gogd.mloopuvs) { /* unlikely to fail */
      gogd.ix = 1.0 / gogd.rx;
      gogd.iy = 1.0 / gogd.ry;

      BLI_task_parallel_range(0, gogd.res_y, &gogd, generate_ocean_geometry_uvs, &settings);
    }
  }

  result->runtime.cd_dirty_vert |= CD_MASK_NORMAL;

  return result;
}

static Mesh *doOcean(ModifierData *md, const ModifierEvalContext *ctx, Mesh *mesh)
{
  OceanModifierData *omd = (OceanModifierData *)md;
  int cfra_scene = (int)DEG_get_ctime(ctx->depsgraph);
  Object *ob = ctx->object;
  bool allocated_ocean = false;

  Mesh *result = NULL;
  OceanResult ocr;

  const int resolution = (ctx->flag & MOD_APPLY_RENDER) ? omd->resolution :
                                                          omd->viewport_resolution;

  MVert *mverts;

  int cfra_for_cache;
  int i, j;

  /* use cached & inverted value for speed
   * expanded this would read...
   *
   * (axis / (omd->size * omd->spatial_size)) + 0.5f) */
#  define OCEAN_CO(_size_co_inv, _v) ((_v * _size_co_inv) + 0.5f)

  const float size_co_inv = 1.0f / (omd->size * omd->spatial_size);

  /* can happen in when size is small, avoid bad array lookups later and quit now */
  if (!isfinite(size_co_inv)) {
    return mesh;
  }

  /* do ocean simulation */
  if (omd->cached == true) {
    if (!omd->oceancache) {
      init_cache_data(ob, omd, resolution);
    }
    BKE_ocean_simulate_cache(omd->oceancache, cfra_scene);
  }
  else {
    /* omd->ocean is NULL on an original object (in contrast to an evaluated one).
     * We can create a new one, but we have to free it as well once we're done.
     * This function is only called on an original object when applying the modifier
     * using the 'Apply Modifier' button, and thus it is not called frequently for
     * simulation. */
    allocated_ocean |= BKE_ocean_ensure(omd, resolution);
    simulate_ocean_modifier(omd);
  }

  if (omd->geometry_mode == MOD_OCEAN_GEOM_GENERATE) {
    result = generate_ocean_geometry(omd, mesh, resolution);
    BKE_mesh_ensure_normals(result);
  }
  else if (omd->geometry_mode == MOD_OCEAN_GEOM_DISPLACE) {
    BKE_id_copy_ex(NULL, &mesh->id, (ID **)&result, LIB_ID_COPY_LOCALIZE);
  }

  cfra_for_cache = cfra_scene;
  CLAMP(cfra_for_cache, omd->bakestart, omd->bakeend);
  cfra_for_cache -= omd->bakestart; /* shift to 0 based */

  mverts = result->mvert;

  /* add vcols before displacement - allows lookup based on position */

  if (omd->flag & MOD_OCEAN_GENERATE_FOAM) {
    if (CustomData_number_of_layers(&result->ldata, CD_MLOOPCOL) < MAX_MCOL) {
      const int num_polys = result->totpoly;
      const int num_loops = result->totloop;
      MLoop *mloops = result->mloop;
      MLoopCol *mloopcols = CustomData_add_layer_named(
          &result->ldata, CD_MLOOPCOL, CD_CALLOC, NULL, num_loops, omd->foamlayername);

      MLoopCol *mloopcols_spray = NULL;
      if (omd->flag & MOD_OCEAN_GENERATE_SPRAY) {
        mloopcols_spray = CustomData_add_layer_named(
            &result->ldata, CD_MLOOPCOL, CD_CALLOC, NULL, num_loops, omd->spraylayername);
      }

      if (mloopcols) { /* unlikely to fail */
        MPoly *mpolys = result->mpoly;
        MPoly *mp;

        for (i = 0, mp = mpolys; i < num_polys; i++, mp++) {
          MLoop *ml = &mloops[mp->loopstart];
          MLoopCol *mlcol = &mloopcols[mp->loopstart];

          MLoopCol *mlcolspray = NULL;
          if (omd->flag & MOD_OCEAN_GENERATE_SPRAY) {
            mlcolspray = &mloopcols_spray[mp->loopstart];
          }

          for (j = mp->totloop; j--; ml++, mlcol++) {
            const float *vco = mverts[ml->v].co;
            const float u = OCEAN_CO(size_co_inv, vco[0]);
            const float v = OCEAN_CO(size_co_inv, vco[1]);
            float foam;

            if (omd->oceancache && omd->cached == true) {
              BKE_ocean_cache_eval_uv(omd->oceancache, &ocr, cfra_for_cache, u, v);
              foam = ocr.foam;
              CLAMP(foam, 0.0f, 1.0f);
            }
            else {
              BKE_ocean_eval_uv(omd->ocean, &ocr, u, v);
              foam = BKE_ocean_jminus_to_foam(ocr.Jminus, omd->foam_coverage);
            }

            mlcol->r = mlcol->g = mlcol->b = (char)(foam * 255);
            /* This needs to be set (render engine uses) */
            mlcol->a = 255;

            if (omd->flag & MOD_OCEAN_GENERATE_SPRAY) {
              if (omd->flag & MOD_OCEAN_INVERT_SPRAY) {
                mlcolspray->r = ocr.Eminus[0] * 255;
              }
              else {
                mlcolspray->r = ocr.Eplus[0] * 255;
              }
              mlcolspray->g = 0;
              if (omd->flag & MOD_OCEAN_INVERT_SPRAY) {
                mlcolspray->b = ocr.Eminus[2] * 255;
              }
              else {
                mlcolspray->b = ocr.Eplus[2] * 255;
              }
              mlcolspray->a = 255;
            }
          }
        }
      }
    }
  }

  /* displace the geometry */

  /* Note: tried to parallelized that one and previous foam loop,
   * but gives 20% slower results... odd. */
  {
    const int num_verts = result->totvert;

    for (i = 0; i < num_verts; i++) {
      float *vco = mverts[i].co;
      const float u = OCEAN_CO(size_co_inv, vco[0]);
      const float v = OCEAN_CO(size_co_inv, vco[1]);

      if (omd->oceancache && omd->cached == true) {
        BKE_ocean_cache_eval_uv(omd->oceancache, &ocr, cfra_for_cache, u, v);
      }
      else {
        BKE_ocean_eval_uv(omd->ocean, &ocr, u, v);
      }

      vco[2] += ocr.disp[1];

      if (omd->chop_amount > 0.0f) {
        vco[0] += ocr.disp[0];
        vco[1] += ocr.disp[2];
      }
    }
  }

  if (allocated_ocean) {
    BKE_ocean_free(omd->ocean);
    omd->ocean = NULL;
  }

#  undef OCEAN_CO

  return result;
}
#else  /* WITH_OCEANSIM */
static Mesh *doOcean(ModifierData *UNUSED(md), const ModifierEvalContext *UNUSED(ctx), Mesh *mesh)
{
  return mesh;
}
#endif /* WITH_OCEANSIM */

static Mesh *modifyMesh(ModifierData *md, const ModifierEvalContext *ctx, Mesh *mesh)
{
  Mesh *result;

  result = doOcean(md, ctx, mesh);

  if (result != mesh) {
    result->runtime.cd_dirty_vert |= CD_MASK_NORMAL;
  }

  return result;
}
// #define WITH_OCEANSIM
static void panel_draw(const bContext *C, Panel *panel)
{
  uiLayout *layout = panel->layout;
#ifdef WITH_OCEANSIM
  uiLayout *col, *sub;

  PointerRNA ptr;
  PointerRNA ob_ptr;
  modifier_panel_get_property_pointers(C, panel, &ob_ptr, &ptr);

  uiLayoutSetPropSep(layout, true);

  col = uiLayoutColumn(layout, false);
  uiItemR(col, &ptr, "geometry_mode", 0, NULL, ICON_NONE);
  if (RNA_enum_get(&ptr, "geometry_mode") == MOD_OCEAN_GEOM_GENERATE) {
    sub = uiLayoutColumn(col, true);
    uiItemR(sub, &ptr, "repeat_x", 0, IFACE_("Repeat X"), ICON_NONE);
    uiItemR(sub, &ptr, "repeat_y", 0, IFACE_("Y"), ICON_NONE);
  }

  sub = uiLayoutColumn(col, true);
  uiItemR(sub, &ptr, "viewport_resolution", 0, IFACE_("Resolution Viewport"), ICON_NONE);
  uiItemR(sub, &ptr, "resolution", 0, IFACE_("Render"), ICON_NONE);

  uiItemR(col, &ptr, "time", 0, NULL, ICON_NONE);

  uiItemR(col, &ptr, "depth", 0, NULL, ICON_NONE);
  uiItemR(col, &ptr, "size", 0, NULL, ICON_NONE);
  uiItemR(col, &ptr, "spatial_size", 0, NULL, ICON_NONE);

  uiItemR(col, &ptr, "random_seed", 0, NULL, ICON_NONE);

  uiItemR(col, &ptr, "use_normals", 0, NULL, ICON_NONE);

  modifier_panel_end(layout, &ptr);

#else  /* WITH_OCEANSIM */
  uiItemL(layout, IFACE_("Built without Ocean modifier"), ICON_NONE);
  UNUSED_VARS(C);
#endif /* WITH_OCEANSIM */
}

#ifdef WITH_OCEANSIM
static void waves_panel_draw(const bContext *C, Panel *panel)
{
  uiLayout *col, *sub;
  uiLayout *layout = panel->layout;

  PointerRNA ptr;
  modifier_panel_get_property_pointers(C, panel, NULL, &ptr);

  uiLayoutSetPropSep(layout, true);

  col = uiLayoutColumn(layout, false);
  uiItemR(col, &ptr, "wave_scale", 0, IFACE_("Scale"), ICON_NONE);
  uiItemR(col, &ptr, "wave_scale_min", 0, NULL, ICON_NONE);
  uiItemR(col, &ptr, "choppiness", 0, NULL, ICON_NONE);
  uiItemR(col, &ptr, "wind_velocity", 0, NULL, ICON_NONE);

  uiItemS(layout);

  col = uiLayoutColumn(layout, false);
  uiItemR(col, &ptr, "wave_alignment", UI_ITEM_R_SLIDER, IFACE_("Alignment"), ICON_NONE);
  sub = uiLayoutColumn(col, false);
  uiLayoutSetActive(sub, RNA_float_get(&ptr, "wave_alignment") > 0.0f);
  uiItemR(sub, &ptr, "wave_direction", 0, IFACE_("Direction"), ICON_NONE);
  uiItemR(sub, &ptr, "damping", 0, NULL, ICON_NONE);
}

static void foam_panel_draw_header(const bContext *C, Panel *panel)
{
  uiLayout *layout = panel->layout;

  PointerRNA ptr;
  modifier_panel_get_property_pointers(C, panel, NULL, &ptr);

  uiItemR(layout, &ptr, "use_foam", 0, IFACE_("Foam"), ICON_NONE);
}

static void foam_panel_draw(const bContext *C, Panel *panel)
{
  uiLayout *col;
  uiLayout *layout = panel->layout;

  PointerRNA ptr;
  modifier_panel_get_property_pointers(C, panel, NULL, &ptr);

  bool use_foam = RNA_boolean_get(&ptr, "use_foam");

  uiLayoutSetPropSep(layout, true);

  col = uiLayoutColumn(layout, false);
  uiLayoutSetActive(col, use_foam);
  uiItemR(col, &ptr, "foam_layer_name", 0, IFACE_("Data Layer"), ICON_NONE);
  uiItemR(col, &ptr, "foam_coverage", 0, IFACE_("Coverage"), ICON_NONE);
}

static void spray_panel_draw_header(const bContext *C, Panel *panel)
{
  uiLayout *row;
  uiLayout *layout = panel->layout;

  PointerRNA ptr;
  modifier_panel_get_property_pointers(C, panel, NULL, &ptr);

  bool use_foam = RNA_boolean_get(&ptr, "use_foam");

  row = uiLayoutRow(layout, false);
  uiLayoutSetActive(row, use_foam);
  uiItemR(row, &ptr, "use_spray", 0, IFACE_("Spray"), ICON_NONE);
}

static void spray_panel_draw(const bContext *C, Panel *panel)
{
  uiLayout *col;
  uiLayout *layout = panel->layout;

  PointerRNA ptr;
  modifier_panel_get_property_pointers(C, panel, NULL, &ptr);

  bool use_foam = RNA_boolean_get(&ptr, "use_foam");
  bool use_spray = RNA_boolean_get(&ptr, "use_spray");

  uiLayoutSetPropSep(layout, true);

  col = uiLayoutColumn(layout, false);
  uiLayoutSetActive(col, use_foam && use_spray);
  uiItemR(col, &ptr, "spray_layer_name", 0, IFACE_("Data Layer"), ICON_NONE);
  uiItemR(col, &ptr, "invert_spray", 0, IFACE_("Invert"), ICON_NONE);
}

static void spectrum_panel_draw(const bContext *C, Panel *panel)
{
  uiLayout *col;
  uiLayout *layout = panel->layout;

  PointerRNA ptr;
  modifier_panel_get_property_pointers(C, panel, NULL, &ptr);

  int spectrum = RNA_enum_get(&ptr, "spectrum");

  uiLayoutSetPropSep(layout, true);

  col = uiLayoutColumn(layout, false);
  uiItemR(col, &ptr, "spectrum", 0, NULL, ICON_NONE);
  if (ELEM(spectrum, MOD_OCEAN_SPECTRUM_TEXEL_MARSEN_ARSLOE, MOD_OCEAN_SPECTRUM_JONSWAP)) {
    uiItemR(col, &ptr, "sharpen_peak_jonswap", UI_ITEM_R_SLIDER, NULL, ICON_NONE);
    uiItemR(col, &ptr, "fetch_jonswap", 0, NULL, ICON_NONE);
  }
}

static void bake_panel_draw(const bContext *C, Panel *panel)
{
  uiLayout *col;
  uiLayout *layout = panel->layout;

  PointerRNA ptr;
  modifier_panel_get_property_pointers(C, panel, NULL, &ptr);

  uiLayoutSetPropSep(layout, true);

  bool is_cached = RNA_boolean_get(&ptr, "is_cached");
  bool use_foam = RNA_boolean_get(&ptr, "use_foam");

  if (is_cached) {
    PointerRNA op_ptr;
    uiItemFullO(layout,
                "OBJECT_OT_ocean_bake",
                IFACE_("Delete Bake"),
                ICON_NONE,
                NULL,
                WM_OP_EXEC_DEFAULT,
                0,
                &op_ptr);
    RNA_boolean_set(&op_ptr, "free", true);
  }
  else {
    uiItemO(layout, NULL, ICON_NONE, "OBJECT_OT_ocean_bake");
  }

  uiItemR(layout, &ptr, "filepath", 0, NULL, ICON_NONE);

  col = uiLayoutColumn(layout, true);
  uiLayoutSetEnabled(col, !is_cached);
  uiItemR(col, &ptr, "frame_start", 0, IFACE_("Frame Start"), ICON_NONE);
  uiItemR(col, &ptr, "frame_end", 0, IFACE_("End"), ICON_NONE);

  col = uiLayoutColumn(layout, false);
  uiLayoutSetActive(col, use_foam);
  uiItemR(col, &ptr, "bake_foam_fade", 0, NULL, ICON_NONE);
}
#endif /* WITH_OCEANSIM */

static void panelRegister(ARegionType *region_type)
{
  PanelType *panel_type = modifier_panel_register(region_type, eModifierType_Ocean, panel_draw);
#ifdef WITH_OCEANSIM
  modifier_subpanel_register(region_type, "waves", "Waves", NULL, waves_panel_draw, panel_type);
  PanelType *foam_panel = modifier_subpanel_register(
      region_type, "foam", "", foam_panel_draw_header, foam_panel_draw, panel_type);
  modifier_subpanel_register(
      region_type, "spray", "", spray_panel_draw_header, spray_panel_draw, foam_panel);
  modifier_subpanel_register(
      region_type, "spectrum", "Spectrum", NULL, spectrum_panel_draw, panel_type);
  modifier_subpanel_register(region_type, "bake", "Bake", NULL, bake_panel_draw, panel_type);
#else
  UNUSED_VARS(panel_type);
#endif /* WITH_OCEANSIM */
}

static void blendRead(BlendDataReader *UNUSED(reader), ModifierData *md)
{
  OceanModifierData *omd = (OceanModifierData *)md;
  omd->oceancache = NULL;
  omd->ocean = NULL;
}

ModifierTypeInfo modifierType_Ocean = {
    /* name */ "Ocean",
    /* structName */ "OceanModifierData",
    /* structSize */ sizeof(OceanModifierData),
    /* type */ eModifierTypeType_Constructive,
    /* flags */ eModifierTypeFlag_AcceptsMesh | eModifierTypeFlag_SupportsEditmode |
        eModifierTypeFlag_EnableInEditmode,

    /* copyData */ copyData,
    /* deformMatrices_DM */ NULL,

    /* deformMatrices */ NULL,
    /* deformVertsEM */ NULL,
    /* deformMatricesEM */ NULL,
    /* modifyMesh */ modifyMesh,
    /* modifyHair */ NULL,
    /* modifyPointCloud */ NULL,
    /* modifyVolume */ NULL,

    /* initData */ initData,
    /* requiredDataMask */ requiredDataMask,
    /* freeData */ freeData,
    /* isDisabled */ NULL,
    /* updateDepsgraph */ NULL,
    /* dependsOnTime */ NULL,
    /* dependsOnNormals */ dependsOnNormals,
    /* foreachObjectLink */ NULL,
    /* foreachIDLink */ NULL,
    /* foreachTexLink */ NULL,
    /* freeRuntimeData */ NULL,
    /* panelRegister */ panelRegister,
    /* blendWrite */ NULL,
    /* blendRead */ blendRead,
};