/* SPDX-FileCopyrightText: 2008 Blender Authors
 *
 * SPDX-License-Identifier: GPL-2.0-or-later */

/** \file
 * \ingroup spoutliner
 */

/* Allow using deprecated functionality for .blend file I/O. */
#define DNA_DEPRECATED_ALLOW

#include <cstring>

#include "MEM_guardedalloc.h"

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

#include "BKE_context.hh"
#include "BKE_lib_query.hh"
#include "BKE_lib_remap.hh"
#include "BKE_outliner_treehash.hh"
#include "BKE_screen.hh"

#include "ED_screen.hh"
#include "ED_space_api.hh"

#include "WM_api.hh"
#include "WM_message.hh"
#include "WM_types.hh"

#include "DNA_scene_types.h"

#include "UI_resources.hh"
#include "UI_view2d.hh"

#include "BLO_read_write.hh"

#include "outliner_intern.hh"
#include "tree/tree_display.hh"

/**
 * Since 2.8x outliner drawing itself can change the scroll position of the outliner
 * after drawing has completed. Failing to draw a second time can cause nothing to display.
 * Making search seem to fail & deleting objects fail to scroll up to show remaining objects.
 * See #128346 for details.
 */
#define USE_OUTLINER_DRAW_CLAMPS_SCROLL_HACK

namespace blender::ed::outliner {

SpaceOutliner_Runtime::SpaceOutliner_Runtime(const SpaceOutliner_Runtime & /*other*/)
    : tree_display(nullptr), tree_hash(nullptr)
{
}

static void outliner_main_region_init(wmWindowManager *wm, ARegion *region)
{
  ListBase *lb;
  wmKeyMap *keymap;

  /* make sure we keep the hide flags */
  region->v2d.scroll |= (V2D_SCROLL_RIGHT | V2D_SCROLL_BOTTOM);
  region->v2d.scroll &= ~(V2D_SCROLL_LEFT | V2D_SCROLL_TOP); /* prevent any noise of past */
  region->v2d.scroll |= V2D_SCROLL_HORIZONTAL_HIDE;
  region->v2d.scroll |= V2D_SCROLL_VERTICAL_HIDE;

  region->v2d.align = (V2D_ALIGN_NO_NEG_X | V2D_ALIGN_NO_POS_Y);
  region->v2d.keepzoom = (V2D_LOCKZOOM_X | V2D_LOCKZOOM_Y | V2D_LIMITZOOM | V2D_KEEPASPECT);
  region->v2d.keeptot = V2D_KEEPTOT_STRICT;
  region->v2d.minzoom = region->v2d.maxzoom = 1.0f;

  UI_view2d_region_reinit(&region->v2d, V2D_COMMONVIEW_LIST, region->winx, region->winy);

  /* own keymap */
  keymap = WM_keymap_ensure(wm->defaultconf, "Outliner", SPACE_OUTLINER, RGN_TYPE_WINDOW);
  WM_event_add_keymap_handler_v2d_mask(&region->runtime->handlers, keymap);

  /* Add dropboxes */
  lb = WM_dropboxmap_find("Outliner", SPACE_OUTLINER, RGN_TYPE_WINDOW);
  WM_event_add_dropbox_handler(&region->runtime->handlers, lb);
}

static void outliner_main_region_draw(const bContext *C, ARegion *region)
{
  View2D *v2d = &region->v2d;

#ifdef USE_OUTLINER_DRAW_CLAMPS_SCROLL_HACK
  const rctf v2d_cur_prev = v2d->cur;
#endif

  UI_ThemeClearColor(TH_BACK);
  draw_outliner(C, true);

#ifdef USE_OUTLINER_DRAW_CLAMPS_SCROLL_HACK
  /* This happens when scrolling is clamped & occasionally when resizing the area.
   * In practice this isn't often which is important as that would hurt performance. */
  if (!BLI_rctf_compare(&v2d->cur, &v2d_cur_prev, FLT_EPSILON)) {
    UI_ThemeClearColor(TH_BACK);
    draw_outliner(C, false);
  }
#endif

  /* reset view matrix */
  UI_view2d_view_restore(C);

  /* scrollers */
  UI_view2d_scrollers_draw(v2d, nullptr);
}

static void outliner_main_region_free(ARegion * /*region*/) {}

static void outliner_main_region_listener(const wmRegionListenerParams *params)
{
  ScrArea *area = params->area;
  ARegion *region = params->region;
  const wmNotifier *wmn = params->notifier;
  SpaceOutliner *space_outliner = static_cast<SpaceOutliner *>(area->spacedata.first);

  /* context changes */
  switch (wmn->category) {
    case NC_WINDOW:
      switch (wmn->action) {
        case NA_ADDED:
        case NA_REMOVED:
          if (space_outliner->outlinevis == SO_DATA_API) {
            ED_region_tag_redraw(region);
          }
          break;
      }
      break;
    case NC_WM:
      switch (wmn->data) {
        case ND_LIB_OVERRIDE_CHANGED:
          ED_region_tag_redraw(region);
          break;
      }
      break;
    case NC_SCENE:
      switch (wmn->data) {
        case ND_OB_ACTIVE:
        case ND_OB_SELECT:
          if (outliner_requires_rebuild_on_select_or_active_change(space_outliner)) {
            ED_region_tag_redraw(region);
          }
          else {
            ED_region_tag_redraw_no_rebuild(region);
          }
          break;
        case ND_FRAME:
          /* Rebuilding the outliner tree is expensive and shouldn't be done when scrubbing. */
          ED_region_tag_redraw_no_rebuild(region);
          break;
        case ND_OB_VISIBLE:
        case ND_OB_RENDER:
        case ND_MODE:
        case ND_KEYINGSET:
        case ND_RENDER_OPTIONS:
        case ND_SEQUENCER:
        case ND_LAYER_CONTENT:
        case ND_WORLD:
        case ND_SCENEBROWSE:
          ED_region_tag_redraw(region);
          break;
        case ND_LAYER:
          /* Avoid rebuild if only the active collection changes */
          if ((wmn->subtype == NS_LAYER_COLLECTION) && (wmn->action == NA_ACTIVATED)) {
            ED_region_tag_redraw_no_rebuild(region);
            break;
          }

          ED_region_tag_redraw(region);
          break;
      }
      if (wmn->action == NA_EDITED) {
        ED_region_tag_redraw_no_rebuild(region);
      }
      break;
    case NC_OBJECT:
      switch (wmn->data) {
        case ND_TRANSFORM:
          ED_region_tag_redraw_no_rebuild(region);
          break;
        case ND_BONE_ACTIVE:
        case ND_BONE_SELECT:
        case ND_BONE_COLLECTION:
        case ND_DRAW:
        case ND_PARENT:
        case ND_OB_SHADING:
          ED_region_tag_redraw(region);
          break;
        case ND_CONSTRAINT:
          /* all constraint actions now, for reordering */
          ED_region_tag_redraw(region);
          break;
        case ND_MODIFIER:
          /* all modifier actions now */
          ED_region_tag_redraw(region);
          break;
        default:
          /* Trigger update for NC_OBJECT itself */
          ED_region_tag_redraw(region);
          break;
      }
      break;
    case NC_GROUP:
      /* All actions now, TODO: check outliner view mode? */
      ED_region_tag_redraw(region);
      break;
    case NC_LAMP:
      /* For updating light icons, when changing light type */
      if (wmn->data == ND_LIGHTING_DRAW) {
        ED_region_tag_redraw(region);
      }
      break;
    case NC_SPACE:
      if (wmn->data == ND_SPACE_OUTLINER) {
        ED_region_tag_redraw(region);
      }
      break;
    case NC_ID:
      if (ELEM(wmn->action, NA_RENAME, NA_ADDED, NA_REMOVED)) {
        ED_region_tag_redraw(region);
      }
      break;
    case NC_ASSET:
      if (ELEM(wmn->action, NA_ADDED, NA_REMOVED)) {
        ED_region_tag_redraw_no_rebuild(region);
      }
      break;
    case NC_MATERIAL:
      switch (wmn->data) {
        case ND_SHADING_LINKS:
          ED_region_tag_redraw_no_rebuild(region);
          break;
      }
      break;
    case NC_GEOM:
      switch (wmn->data) {
        case ND_VERTEX_GROUP:
          ED_region_tag_redraw(region);
          break;
        case ND_DATA:
          if (wmn->action == NA_RENAME) {
            ED_region_tag_redraw(region);
          }
          break;
      }
      break;
    case NC_ANIMATION:
      switch (wmn->data) {
        case ND_NLA_ACTCHANGE:
        case ND_KEYFRAME:
          ED_region_tag_redraw(region);
          break;
        case ND_ANIMCHAN:
          if (ELEM(wmn->action, NA_SELECTED, NA_RENAME)) {
            ED_region_tag_redraw(region);
          }
          break;
        case ND_NLA:
          if (ELEM(wmn->action, NA_ADDED, NA_REMOVED)) {
            ED_region_tag_redraw(region);
          }
          break;
        case ND_NLA_ORDER:
          ED_region_tag_redraw(region);
          break;
      }
      break;
    case NC_GPENCIL:
      if (ELEM(wmn->action, NA_EDITED, NA_SELECTED, NA_RENAME)) {
        ED_region_tag_redraw(region);
      }
      break;
    case NC_SCREEN:
      if (ELEM(wmn->data, ND_LAYOUTDELETE, ND_LAYER)) {
        ED_region_tag_redraw(region);
      }
      break;
    case NC_MASK:
      if (ELEM(wmn->action, NA_ADDED)) {
        ED_region_tag_redraw(region);
      }
      break;
    case NC_PAINTCURVE:
      if (ELEM(wmn->action, NA_ADDED)) {
        ED_region_tag_redraw(region);
      }
      break;
    case NC_TEXT:
      if (ELEM(wmn->action, NA_ADDED, NA_REMOVED)) {
        ED_region_tag_redraw(region);
      }
      break;
    case NC_NODE:
      if (ELEM(wmn->action, NA_ADDED, NA_REMOVED) &&
          ELEM(space_outliner->outlinevis, SO_LIBRARIES, SO_DATA_API))
      {
        ED_region_tag_redraw(region);
      }
      break;
    case NC_IMAGE:
      if (ELEM(wmn->action, NA_ADDED, NA_REMOVED) &&
          ELEM(space_outliner->outlinevis, SO_LIBRARIES, SO_DATA_API))
      {
        ED_region_tag_redraw(region);
      }
      break;
  }
}

static void outliner_main_region_message_subscribe(const wmRegionMessageSubscribeParams *params)
{
  wmMsgBus *mbus = params->message_bus;
  ScrArea *area = params->area;
  ARegion *region = params->region;
  SpaceOutliner *space_outliner = static_cast<SpaceOutliner *>(area->spacedata.first);

  wmMsgSubscribeValue msg_sub_value_region_tag_redraw{};
  msg_sub_value_region_tag_redraw.owner = region;
  msg_sub_value_region_tag_redraw.user_data = region;
  msg_sub_value_region_tag_redraw.notify = ED_region_do_msg_notify_tag_redraw;

  if (ELEM(space_outliner->outlinevis, SO_VIEW_LAYER, SO_SCENES, SO_OVERRIDES_LIBRARY)) {
    WM_msg_subscribe_rna_anon_prop(mbus, Window, view_layer, &msg_sub_value_region_tag_redraw);
  }
}

/* ************************ header outliner area region *********************** */

/* add handlers, stuff you only do once or on area/region changes */
static void outliner_header_region_init(wmWindowManager * /*wm*/, ARegion *region)
{
  ED_region_header_init(region);
}

static void outliner_header_region_draw(const bContext *C, ARegion *region)
{
  ED_region_header(C, region);
}

static void outliner_header_region_free(ARegion * /*region*/) {}

static void outliner_header_region_listener(const wmRegionListenerParams *params)
{
  ARegion *region = params->region;
  const wmNotifier *wmn = params->notifier;

  /* context changes */
  switch (wmn->category) {
    case NC_SCENE:
      switch (wmn->data) {
        case ND_KEYINGSET:
          ED_region_tag_redraw(region);
          break;
        case ND_LAYER:
          /* Not needed by blender itself, but requested by add-on developers. #109995 */
          if ((wmn->subtype == NS_LAYER_COLLECTION) && (wmn->action == NA_ACTIVATED)) {
            ED_region_tag_redraw(region);
          }
          break;
      }
      break;
    case NC_SPACE:
      if (wmn->data == ND_SPACE_OUTLINER) {
        ED_region_tag_redraw(region);
      }
      break;
  }
}

/* ******************** default callbacks for outliner space ***************** */

static SpaceLink *outliner_create(const ScrArea * /*area*/, const Scene * /*scene*/)
{
  ARegion *region;
  SpaceOutliner *space_outliner;

  space_outliner = MEM_callocN<SpaceOutliner>("initoutliner");
  space_outliner->spacetype = SPACE_OUTLINER;
  space_outliner->filter_id_type = ID_GR;
  space_outliner->show_restrict_flags = SO_RESTRICT_ENABLE | SO_RESTRICT_HIDE | SO_RESTRICT_RENDER;
  space_outliner->outlinevis = SO_VIEW_LAYER;
  space_outliner->sync_select_dirty |= WM_OUTLINER_SYNC_SELECT_FROM_ALL;
  space_outliner->flag = SO_SYNC_SELECT | SO_MODE_COLUMN;
  space_outliner->filter = SO_FILTER_NO_VIEW_LAYERS;

  /* header */
  region = BKE_area_region_new();

  BLI_addtail(&space_outliner->regionbase, region);
  region->regiontype = RGN_TYPE_HEADER;
  region->alignment = (U.uiflag & USER_HEADER_BOTTOM) ? RGN_ALIGN_BOTTOM : RGN_ALIGN_TOP;

  /* main region */
  region = BKE_area_region_new();

  BLI_addtail(&space_outliner->regionbase, region);
  region->regiontype = RGN_TYPE_WINDOW;

  return (SpaceLink *)space_outliner;
}

/* Doesn't free the space-link itself. */
static void outliner_free(SpaceLink *sl)
{
  SpaceOutliner *space_outliner = (SpaceOutliner *)sl;

  outliner_free_tree(&space_outliner->tree);
  if (space_outliner->treestore) {
    BLI_mempool_destroy(space_outliner->treestore);
  }

  MEM_delete(space_outliner->runtime);
}

/* spacetype; init callback */
static void outliner_init(wmWindowManager * /*wm*/, ScrArea *area)
{
  SpaceOutliner *space_outliner = static_cast<SpaceOutliner *>(area->spacedata.first);

  if (space_outliner->runtime == nullptr) {
    space_outliner->runtime = MEM_new<SpaceOutliner_Runtime>("SpaceOutliner_Runtime");
  }
}

static SpaceLink *outliner_duplicate(SpaceLink *sl)
{
  SpaceOutliner *space_outliner = (SpaceOutliner *)sl;
  SpaceOutliner *space_outliner_new = MEM_dupallocN<SpaceOutliner>(__func__, *space_outliner);

  BLI_listbase_clear(&space_outliner_new->tree);
  space_outliner_new->treestore = nullptr;

  space_outliner_new->sync_select_dirty = WM_OUTLINER_SYNC_SELECT_FROM_ALL;

  if (space_outliner->runtime) {
    /* Copy constructor handles details. */
    space_outliner_new->runtime = MEM_new<SpaceOutliner_Runtime>("SpaceOutliner_runtime dup",
                                                                 *space_outliner->runtime);
  }

  return (SpaceLink *)space_outliner_new;
}

static void outliner_id_remap(ScrArea *area,
                              SpaceLink *slink,
                              const blender::bke::id::IDRemapper &mappings)
{
  SpaceOutliner *space_outliner = (SpaceOutliner *)slink;

  if (!space_outliner->treestore) {
    return;
  }

  TreeStoreElem *tselem;
  BLI_mempool_iter iter;
  bool changed = false;
  bool unassigned = false;

  BLI_mempool_iternew(space_outliner->treestore, &iter);
  while ((tselem = static_cast<TreeStoreElem *>(BLI_mempool_iterstep(&iter)))) {
    switch (mappings.apply(&tselem->id, ID_REMAP_APPLY_DEFAULT)) {
      case ID_REMAP_RESULT_SOURCE_REMAPPED:
        changed = true;
        break;
      case ID_REMAP_RESULT_SOURCE_UNASSIGNED:
        changed = true;
        unassigned = true;
        break;
      case ID_REMAP_RESULT_SOURCE_UNAVAILABLE:
      case ID_REMAP_RESULT_SOURCE_NOT_MAPPABLE:
        break;
    }
  }

  /* Note that the Outliner may not be the active editor of the area, and hence not initialized.
   * So runtime data might not have been created yet. */
  if (space_outliner->runtime && space_outliner->runtime->tree_hash && changed) {
    /* rebuild hash table, because it depends on ids too */
    /* postpone a full rebuild because this can be called many times on-free */
    space_outliner->storeflag |= SO_TREESTORE_REBUILD;

    if (unassigned) {
      /* Redraw is needed when removing data for multiple outlines show the same data.
       * without this, the stale data won't get fully flushed when this outliner
       * is not the active outliner the user is interacting with. See #85976. */
      ED_area_tag_redraw(area);
    }
  }
}

static void outliner_foreach_id(SpaceLink *space_link, LibraryForeachIDData *data)
{
  SpaceOutliner *space_outliner = reinterpret_cast<SpaceOutliner *>(space_link);
  if (!space_outliner->treestore) {
    return;
  }
  const int data_flags = BKE_lib_query_foreachid_process_flags_get(data);
  const bool is_readonly = (data_flags & IDWALK_READONLY) != 0;
  const bool allow_pointer_access = (data_flags & IDWALK_NO_ORIG_POINTERS_ACCESS) == 0;

  BLI_mempool_iter iter;
  BLI_mempool_iternew(space_outliner->treestore, &iter);
  while (TreeStoreElem *tselem = static_cast<TreeStoreElem *>(BLI_mempool_iterstep(&iter))) {
    /* Do not try to restore non-ID pointers (drivers/sequence/etc.). */
    if (TSE_IS_REAL_ID(tselem)) {
      /* NOTE: Outliner ID pointers are never `IDWALK_CB_DIRECT_WEAK_LINK`, they should never
       * enforce keeping a reference to some linked data. */
      const LibraryForeachIDCallbackFlag cb_flag = (tselem->id != nullptr &&
                                                    allow_pointer_access &&
                                                    (tselem->id->flag & ID_FLAG_EMBEDDED_DATA) !=
                                                        0) ?
                                                       IDWALK_CB_EMBEDDED_NOT_OWNING :
                                                       IDWALK_CB_NOP;
      BKE_LIB_FOREACHID_PROCESS_ID(data, tselem->id, cb_flag);
    }
    else if (!is_readonly) {
      tselem->id = nullptr;
    }
  }
  if (!is_readonly) {
    /* rebuild hash table, because it depends on ids too */
    space_outliner->storeflag |= SO_TREESTORE_REBUILD;
  }
}

static void outliner_deactivate(ScrArea *area)
{
  /* Remove hover highlights */
  SpaceOutliner *space_outliner = static_cast<SpaceOutliner *>(area->spacedata.first);
  outliner_flag_set(*space_outliner, TSE_HIGHLIGHTED_ANY, false);
  ED_region_tag_redraw_no_rebuild(BKE_area_find_region_type(area, RGN_TYPE_WINDOW));
}

static void outliner_space_blend_read_data(BlendDataReader *reader, SpaceLink *sl)
{
  SpaceOutliner *space_outliner = (SpaceOutliner *)sl;

  /* use #BLO_read_get_new_data_address_no_us and do not free old memory avoiding double
   * frees and use of freed memory. this could happen because of a
   * bug fixed in revision 58959 where the treestore memory address
   * was not unique */
  TreeStore *ts = static_cast<TreeStore *>(
      BLO_read_get_new_data_address_no_us(reader, space_outliner->treestore, sizeof(TreeStore)));
  space_outliner->treestore = nullptr;
  if (ts) {
    TreeStoreElem *elems = static_cast<TreeStoreElem *>(BLO_read_get_new_data_address_no_us(
        reader, ts->data, sizeof(TreeStoreElem) * ts->usedelem));

    space_outliner->treestore = BLI_mempool_create(
        sizeof(TreeStoreElem), ts->usedelem, 512, BLI_MEMPOOL_ALLOW_ITER);
    if (ts->usedelem && elems) {
      for (int i = 0; i < ts->usedelem; i++) {
        TreeStoreElem *new_elem = static_cast<TreeStoreElem *>(
            BLI_mempool_alloc(space_outliner->treestore));
        *new_elem = elems[i];
      }
    }
    /* we only saved what was used */
    space_outliner->storeflag |= SO_TREESTORE_CLEANUP; /* at first draw */
  }
  BLI_listbase_clear(&space_outliner->tree);
  space_outliner->runtime = nullptr;
}

static void outliner_space_blend_read_after_liblink(BlendLibReader * /*reader*/,
                                                    ID * /*parent_id*/,
                                                    SpaceLink *sl)
{
  SpaceOutliner *space_outliner = reinterpret_cast<SpaceOutliner *>(sl);

  if (space_outliner->treestore) {
    TreeStoreElem *tselem;
    BLI_mempool_iter iter;

    BLI_mempool_iternew(space_outliner->treestore, &iter);
    while ((tselem = static_cast<TreeStoreElem *>(BLI_mempool_iterstep(&iter)))) {
      if (!TSE_IS_REAL_ID(tselem)) {
        tselem->id = nullptr;
      }
    }
    /* rebuild hash table, because it depends on ids too */
    space_outliner->storeflag |= SO_TREESTORE_REBUILD;
  }
}

static void write_space_outliner(BlendWriter *writer, const SpaceOutliner *space_outliner)
{
  BLI_mempool *ts = space_outliner->treestore;

  if (ts) {
    const int elems = BLI_mempool_len(ts);
    /* linearize mempool to array */
    TreeStoreElem *data = elems ? static_cast<TreeStoreElem *>(
                                      BLI_mempool_as_arrayN(ts, "TreeStoreElem")) :
                                  nullptr;

    if (data) {
      BLO_write_struct(writer, SpaceOutliner, space_outliner);

      /* To store #TreeStore (instead of the mempool), two unique memory addresses are needed,
       * which can be used to identify the data on read:
       * 1) One for the #TreeStore data itself.
       * 2) One for the array of #TreeStoreElem's inside #TreeStore (#TreeStore.data).
       *
       * For 1) we just use the mempool's address (#SpaceOutliner::treestore).
       * For 2) we don't have such a direct choice. We can't just use the array's address from
       * above, since that may not be unique over all Outliners. So instead use an address relative
       * to 1).
       */
      /* TODO the mempool could be moved to #SpaceOutliner_Runtime so that #SpaceOutliner could
       * hold the #TreeStore directly. */

      /* Address relative to the tree-store, as noted above. */
      void *data_addr = (void *)POINTER_OFFSET(ts, sizeof(void *));
      /* There should be plenty of memory addresses within the mempool data that we can point into,
       * just double-check we don't potentially end up with a memory address that another DNA
       * struct might use. Assumes BLI_mempool uses the guarded allocator. */
      BLI_assert(MEM_allocN_len(ts) >= sizeof(void *) * 2);

      TreeStore ts_flat = {0};
      ts_flat.usedelem = elems;
      ts_flat.totelem = elems;
      ts_flat.data = static_cast<TreeStoreElem *>(data_addr);

      BLO_write_struct_at_address(writer, TreeStore, ts, &ts_flat);
      BLO_write_struct_array_at_address(writer, TreeStoreElem, elems, data_addr, data);

      MEM_freeN(data);
    }
    else {
      SpaceOutliner space_outliner_flat = *space_outliner;
      space_outliner_flat.treestore = nullptr;
      BLO_write_struct_at_address(writer, SpaceOutliner, space_outliner, &space_outliner_flat);
    }
  }
  else {
    BLO_write_struct(writer, SpaceOutliner, space_outliner);
  }
}

static void outliner_space_blend_write(BlendWriter *writer, SpaceLink *sl)
{
  SpaceOutliner *space_outliner = (SpaceOutliner *)sl;
  write_space_outliner(writer, space_outliner);
}

}  // namespace blender::ed::outliner

void ED_spacetype_outliner()
{
  using namespace blender::ed::outliner;

  std::unique_ptr<SpaceType> st = std::make_unique<SpaceType>();
  ARegionType *art;

  st->spaceid = SPACE_OUTLINER;
  STRNCPY(st->name, "Outliner");

  st->create = outliner_create;
  st->free = outliner_free;
  st->init = outliner_init;
  st->duplicate = outliner_duplicate;
  st->operatortypes = outliner_operatortypes;
  st->keymap = outliner_keymap;
  st->dropboxes = outliner_dropboxes;
  st->id_remap = outliner_id_remap;
  st->foreach_id = outliner_foreach_id;
  st->deactivate = outliner_deactivate;
  st->blend_read_data = outliner_space_blend_read_data;
  st->blend_read_after_liblink = outliner_space_blend_read_after_liblink;
  st->blend_write = outliner_space_blend_write;

  /* regions: main window */
  art = MEM_callocN<ARegionType>("spacetype outliner region");
  art->regionid = RGN_TYPE_WINDOW;
  art->keymapflag = ED_KEYMAP_UI | ED_KEYMAP_VIEW2D;

  art->init = outliner_main_region_init;
  art->draw = outliner_main_region_draw;
  art->free = outliner_main_region_free;
  art->listener = outliner_main_region_listener;
  art->message_subscribe = outliner_main_region_message_subscribe;
  art->context = outliner_main_region_context;
  BLI_addhead(&st->regiontypes, art);

  /* regions: header */
  art = MEM_callocN<ARegionType>("spacetype outliner header region");
  art->regionid = RGN_TYPE_HEADER;
  art->prefsizey = HEADERY;
  art->keymapflag = ED_KEYMAP_UI | ED_KEYMAP_VIEW2D | ED_KEYMAP_HEADER;

  art->init = outliner_header_region_init;
  art->draw = outliner_header_region_draw;
  art->free = outliner_header_region_free;
  art->listener = outliner_header_region_listener;
  BLI_addhead(&st->regiontypes, art);

  BKE_spacetype_register(std::move(st));
}
