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

/** \file
 * \ingroup modifiers
 */

#include <stdio.h>

#include "BLI_listbase.h"
#include "BLI_math_vector.h"
#include "BLI_utildefines.h"

#include "BLT_translation.h"

#include "DNA_defaults.h"
#include "DNA_gpencil_modifier_types.h"
#include "DNA_gpencil_types.h"
#include "DNA_modifier_types.h"
#include "DNA_object_types.h"
#include "DNA_scene_types.h"
#include "DNA_screen_types.h"

#include "BKE_armature.h"
#include "BKE_context.h"
#include "BKE_gpencil.h"
#include "BKE_gpencil_geom.h"
#include "BKE_gpencil_modifier.h"
#include "BKE_lib_query.h"
#include "BKE_main.h"
#include "BKE_modifier.h"
#include "BKE_scene.h"
#include "BKE_screen.h"

#include "MEM_guardedalloc.h"

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

#include "RNA_access.h"

#include "MOD_gpencil_modifiertypes.h"
#include "MOD_gpencil_ui_common.h"
#include "MOD_gpencil_util.h"

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

static void initData(GpencilModifierData *md)
{
  ArmatureGpencilModifierData *gpmd = (ArmatureGpencilModifierData *)md;

  BLI_assert(MEMCMP_STRUCT_AFTER_IS_ZERO(gpmd, modifier));

  MEMCPY_STRUCT_AFTER(gpmd, DNA_struct_default_get(ArmatureGpencilModifierData), modifier);
}

static void copyData(const GpencilModifierData *md, GpencilModifierData *target)
{
  BKE_gpencil_modifier_copydata_generic(md, target);
}

static void gpencil_deform_verts(ArmatureGpencilModifierData *mmd, Object *target, bGPDstroke *gps)
{
  bGPDspoint *pt = gps->points;
  float(*vert_coords)[3] = MEM_mallocN(sizeof(float[3]) * gps->totpoints, __func__);
  int i;

  BKE_gpencil_dvert_ensure(gps);

  /* prepare array of points */
  for (i = 0; i < gps->totpoints; i++, pt++) {
    copy_v3_v3(vert_coords[i], &pt->x);
  }

  /* deform verts */
  BKE_armature_deform_coords_with_gpencil_stroke(mmd->object,
                                                 target,
                                                 vert_coords,
                                                 NULL,
                                                 gps->totpoints,
                                                 mmd->deformflag,
                                                 mmd->vert_coords_prev,
                                                 mmd->vgname,
                                                 gps);

  /* Apply deformed coordinates */
  pt = gps->points;
  for (i = 0; i < gps->totpoints; i++, pt++) {
    copy_v3_v3(&pt->x, vert_coords[i]);
  }

  MEM_freeN(vert_coords);
}

/* deform stroke */
static void deformStroke(GpencilModifierData *md,
                         Depsgraph *UNUSED(depsgraph),
                         Object *ob,
                         bGPDlayer *UNUSED(gpl),
                         bGPDframe *UNUSED(gpf),
                         bGPDstroke *gps)
{
  ArmatureGpencilModifierData *mmd = (ArmatureGpencilModifierData *)md;
  if (!mmd->object) {
    return;
  }
  bGPdata *gpd = ob->data;

  gpencil_deform_verts(mmd, ob, gps);
  /* Calc geometry data. */
  BKE_gpencil_stroke_geometry_update(gpd, gps);
}

static void bakeModifier(Main *UNUSED(bmain),
                         Depsgraph *depsgraph,
                         GpencilModifierData *md,
                         Object *ob)
{
  Object *object_eval = DEG_get_evaluated_object(depsgraph, ob);
  ArmatureGpencilModifierData *mmd = (ArmatureGpencilModifierData *)md;
  GpencilModifierData *md_eval = BKE_gpencil_modifiers_findby_name(object_eval, md->name);

  if (mmd->object == NULL) {
    return;
  }
  generic_bake_deform_stroke(depsgraph, md_eval, object_eval, true, deformStroke);
}

static bool isDisabled(GpencilModifierData *md, int UNUSED(userRenderParams))
{
  ArmatureGpencilModifierData *mmd = (ArmatureGpencilModifierData *)md;

  /* The object type check is only needed here in case we have a placeholder
   * object assigned (because the library containing the armature is missing).
   *
   * In other cases it should be impossible to have a type mismatch. */
  return !mmd->object || mmd->object->type != OB_ARMATURE;
}

static void updateDepsgraph(GpencilModifierData *md,
                            const ModifierUpdateDepsgraphContext *ctx,
                            const int UNUSED(mode))
{
  ArmatureGpencilModifierData *lmd = (ArmatureGpencilModifierData *)md;
  if (lmd->object != NULL) {
    DEG_add_object_relation(ctx->node, lmd->object, DEG_OB_COMP_EVAL_POSE, "Armature Modifier");
    DEG_add_object_relation(ctx->node, lmd->object, DEG_OB_COMP_TRANSFORM, "Armature Modifier");
  }
  DEG_add_object_relation(ctx->node, ctx->object, DEG_OB_COMP_TRANSFORM, "Armature Modifier");
}

static void foreachIDLink(GpencilModifierData *md, Object *ob, IDWalkFunc walk, void *userData)
{
  ArmatureGpencilModifierData *mmd = (ArmatureGpencilModifierData *)md;

  walk(userData, ob, (ID **)&mmd->object, IDWALK_CB_NOP);
}

static void panel_draw(const bContext *UNUSED(C), Panel *panel)
{
  uiLayout *sub, *row, *col;
  uiLayout *layout = panel->layout;

  PointerRNA ob_ptr;
  PointerRNA *ptr = gpencil_modifier_panel_get_property_pointers(panel, &ob_ptr);

  bool has_vertex_group = RNA_string_length(ptr, "vertex_group") != 0;

  uiLayoutSetPropSep(layout, true);

  uiItemR(layout, ptr, "object", 0, NULL, ICON_NONE);
  row = uiLayoutRow(layout, true);
  uiItemPointerR(row, ptr, "vertex_group", &ob_ptr, "vertex_groups", NULL, ICON_NONE);
  sub = uiLayoutRow(row, true);
  uiLayoutSetActive(sub, has_vertex_group);
  uiLayoutSetPropDecorate(sub, false);
  uiItemR(sub, ptr, "invert_vertex_group", 0, "", ICON_ARROW_LEFTRIGHT);

  col = uiLayoutColumnWithHeading(layout, true, IFACE_("Bind To"));
  uiItemR(col, ptr, "use_vertex_groups", 0, IFACE_("Vertex Groups"), ICON_NONE);
  uiItemR(col, ptr, "use_bone_envelopes", 0, IFACE_("Bone Envelopes"), ICON_NONE);

  gpencil_modifier_panel_end(layout, ptr);
}

static void panelRegister(ARegionType *region_type)
{
  gpencil_modifier_panel_register(region_type, eGpencilModifierType_Armature, panel_draw);
}

GpencilModifierTypeInfo modifierType_Gpencil_Armature = {
    /* name */ N_("Armature"),
    /* structName */ "ArmatureGpencilModifierData",
    /* structSize */ sizeof(ArmatureGpencilModifierData),
    /* type */ eGpencilModifierTypeType_Gpencil,
    /* flags */ eGpencilModifierTypeFlag_SupportsEditmode,

    /* copyData */ copyData,

    /* deformStroke */ deformStroke,
    /* generateStrokes */ NULL,
    /* bakeModifier */ bakeModifier,
    /* remapTime */ NULL,
    /* initData */ initData,
    /* freeData */ NULL,
    /* isDisabled */ isDisabled,
    /* updateDepsgraph */ updateDepsgraph,
    /* dependsOnTime */ NULL,
    /* foreachIDLink */ foreachIDLink,
    /* foreachTexLink */ NULL,
    /* panelRegister */ panelRegister,
};