/* SPDX-FileCopyrightText: 2001-2002 NaN Holding BV. All rights reserved.
 * SPDX-FileCopyrightText: 2003-2009 Blender Authors
 * SPDX-FileCopyrightText: 2005-2006 Peter Schlaile <peter [at] schlaile [dot] de>
 *
 * SPDX-License-Identifier: GPL-2.0-or-later */

/** \file
 * \ingroup sequencer
 */

#define DNA_DEPRECATED_ALLOW

#include <cstddef>

#include "MEM_guardedalloc.h"

#include "DNA_listBase.h"
#include "DNA_mask_types.h"
#include "DNA_movieclip_types.h"
#include "DNA_scene_types.h"
#include "DNA_sequence_types.h"
#include "DNA_sound_types.h"

#include "BLI_assert.h"
#include "BLI_listbase.h"
#include "BLI_map.hh"
#include "BLI_path_utils.hh"
#include "BLI_string.h"
#include "BLI_string_utf8.h"

#include "BKE_duplilist.hh"
#include "BKE_fcurve.hh"
#include "BKE_idprop.hh"
#include "BKE_layer.hh"
#include "BKE_lib_id.hh"
#include "BKE_lib_remap.hh"
#include "BKE_main.hh"
#include "BKE_scene.hh"
#include "BKE_sound.hh"

#include "DEG_depsgraph.hh"
#include "DEG_depsgraph_query.hh"

#include "MOV_read.hh"

#include "SEQ_channels.hh"
#include "SEQ_connect.hh"
#include "SEQ_edit.hh"
#include "SEQ_iterator.hh"
#include "SEQ_modifier.hh"
#include "SEQ_preview_cache.hh"
#include "SEQ_proxy.hh"
#include "SEQ_relations.hh"
#include "SEQ_retiming.hh"
#include "SEQ_sequencer.hh"
#include "SEQ_sound.hh"
#include "SEQ_thumbnail_cache.hh"
#include "SEQ_transform.hh"
#include "SEQ_utils.hh"

#include "BLO_read_write.hh"

#include "cache/compositor_cache.hh"
#include "cache/final_image_cache.hh"
#include "cache/intra_frame_cache.hh"
#include "cache/source_image_cache.hh"
#include "effects/effects.hh"
#include "modifiers/modifier.hh"
#include "prefetch.hh"
#include "sequencer.hh"

#include "BKE_scene_runtime.hh"

namespace blender {
namespace seq {

/* -------------------------------------------------------------------- */
/** \name Allocate / Free Functions
 * \{ */

StripProxy *seq_strip_proxy_alloc()
{
  StripProxy *strip_proxy = MEM_new<StripProxy>("StripProxy");
  strip_proxy->quality = 50;
  return strip_proxy;
}

static StripData *strip_data_alloc(StripType type)
{
  StripData *data = MEM_new<StripData>("strip");

  if (type != STRIP_TYPE_SOUND) {
    data->transform = MEM_new<StripTransform>("StripTransform");
    data->transform->scale_x = 1;
    data->transform->scale_y = 1;
    data->transform->origin[0] = 0.5f;
    data->transform->origin[1] = 0.5f;
    data->transform->filter = SEQ_TRANSFORM_FILTER_AUTO;
    data->crop = MEM_new<StripCrop>("StripCrop");
  }
  return data;
}

static void strip_data_free(StripData *data)
{
  if (data->stripdata) {
    MEM_delete(data->stripdata);
  }

  if (data->proxy) {
    if (data->proxy->anim) {
      MOV_close(data->proxy->anim);
    }

    MEM_delete(data->proxy);
  }
  if (data->crop) {
    MEM_delete(data->crop);
  }
  if (data->transform) {
    MEM_delete(data->transform);
  }

  MEM_delete(data);
}

Strip *strip_alloc(ListBaseT<Strip> *lb, int timeline_frame, int channel, StripType type)
{
  Strip *strip = MEM_new<Strip>("addseq");
  strip->runtime = MEM_new<StripRuntime>(__func__);
  relations_session_uid_generate(strip);
  BLI_addtail(lb, strip);

  *(reinterpret_cast<short *>(strip->name)) = ID_SEQ;
  strip->name[2] = 0;

  strip->flag = SEQ_SELECT;
  strip->start = timeline_frame;
  strip_channel_set(strip, channel);
  strip->sat = 1.0;
  strip->mul = 1.0;
  strip->blend_opacity = 100.0;
  strip->volume = 1.0f;
  strip->type = type;
  strip->media_playback_rate = 0.0f;
  strip->speed_factor = 1.0f;

  if (strip->type == STRIP_TYPE_ADJUSTMENT) {
    strip->blend_mode = STRIP_BLEND_CROSS;
  }
  else {
    strip->blend_mode = STRIP_BLEND_ALPHAOVER;
  }

  strip->data = strip_data_alloc(type);
  strip->stereo3d_format = MEM_new<Stereo3dFormat>("Sequence Stereo Format");

  strip->color_tag = STRIP_COLOR_NONE;

  if (strip->type == STRIP_TYPE_META) {
    channels_ensure(&strip->channels);
  }

  return strip;
}

/* only give option to skip cache locally (static func) */
static void seq_strip_free_ex(Scene *scene,
                              Strip *strip,
                              const bool do_cache,
                              const bool do_id_user)
{
  if (strip->data) {
    strip_data_free(strip->data);
    strip->data = nullptr;
  }

  strip_free_movie_readers(strip);

  if (strip->is_effect()) {
    EffectHandle sh = strip_effect_handle_get(strip);
    if (sh.free) {
      sh.free(strip, do_id_user);
    }
  }

  if (strip->sound && do_id_user) {
    id_us_min(id_cast<ID *>(strip->sound));
  }

  if (strip->clip && do_id_user) {
    id_us_min(&strip->clip->id);
  }

  if (strip->mask && do_id_user) {
    id_us_min(&strip->mask->id);
  }

  if (strip->stereo3d_format) {
    MEM_delete(strip->stereo3d_format);
  }

  /* clipboard has no scene and will never have a sound handle or be active
   * same goes to sequences copy for proxy rebuild job
   */
  if (scene) {
    Editing *ed = scene->ed;

    if (ed->act_strip == strip) {
      ed->act_strip = nullptr;
    }

    if (strip->runtime->scene_sound && ELEM(strip->type, STRIP_TYPE_SOUND, STRIP_TYPE_SCENE)) {
      BKE_sound_remove_scene_sound(scene, strip->runtime->scene_sound);
      strip->runtime->scene_sound.reset();
    }
  }

  if (strip->prop) {
    IDP_FreeProperty_ex(strip->prop, do_id_user);
  }
  if (strip->system_properties) {
    IDP_FreeProperty_ex(strip->system_properties, do_id_user);
  }

  /* free modifiers */
  modifier_clear(strip);

  if (is_strip_connected(strip)) {
    disconnect(strip);
  }

  /* free cached data used by this strip,
   * also invalidate cache for all dependent sequences
   *
   * be _very_ careful here, invalidating cache loops over the scene sequences and
   * assumes the listbase is valid for all strips,
   * this may not be the case if lists are being freed.
   * this is optional SEQ_relations_invalidate_cache
   */
  if (do_cache) {
    if (scene) {
      relations_invalidate_cache_raw(scene, strip);
    }
  }
  if (strip->type == STRIP_TYPE_META) {
    channels_free(&strip->channels);
  }

  if (strip->retiming_keys != nullptr) {
    MEM_delete(strip->retiming_keys);
    strip->retiming_keys = nullptr;
    strip->retiming_keys_num = 0;
  }

  MEM_SAFE_DELETE(strip->scene_view_layer_name);

  MEM_SAFE_DELETE(strip->runtime);
  MEM_delete(strip);
}

void strip_free(Scene *scene, Strip *strip)
{
  seq_strip_free_ex(scene, strip, true, true);
}

void seq_free_strip_recurse(Scene *scene, Strip *strip, const bool do_id_user)
{
  Strip *istrip_next;

  for (Strip *istrip = static_cast<Strip *>(strip->seqbase.first); istrip; istrip = istrip_next) {
    istrip_next = istrip->next;
    seq_free_strip_recurse(scene, istrip, do_id_user);
  }

  seq_strip_free_ex(scene, strip, false, do_id_user);
}

StripRuntime::~StripRuntime()
{
  clear_sound_time_stretch();
}

void StripRuntime::clear_sound_time_stretch()
{
  sound_time_stretch.reset();
  sound_time_stretch_fps = 0.0f;
}

void StripRuntime::remove_scene_sound(Scene *scene)
{
  if (scene_sound != nullptr) {
    BKE_sound_remove_scene_sound(scene, scene_sound);
    scene_sound.reset();
  }
}

Editing *editing_get(const Scene *scene)
{
  return scene ? scene->ed : nullptr;
}

Editing *editing_ensure(Scene *scene)
{
  if (scene->ed == nullptr) {
    Editing *ed = scene->ed = MEM_new<Editing>("addseq");
    ed->cache_flag = (SEQ_CACHE_PREFETCH_ENABLE | SEQ_CACHE_STORE_FINAL_OUT | SEQ_CACHE_STORE_RAW);
    ed->show_missing_media_flag = SEQ_EDIT_SHOW_MISSING_MEDIA;
    channels_ensure(&ed->channels);
  }

  return scene->ed;
}

void editing_free(Scene *scene, const bool do_id_user)
{
  Editing *ed = scene->ed;

  if (ed == nullptr) {
    return;
  }

  seq_prefetch_free(scene);

  /* handle cache freeing above */
  for (Strip &strip : ed->seqbase.items_mutable()) {
    seq_free_strip_recurse(scene, &strip, do_id_user);
  }

  ed->metastack.free_no_destruct();
  strip_lookup_free(ed);
  media_presence_free(scene);
  thumbnail_cache_destroy(scene);
  intra_frame_cache_destroy(scene);
  source_image_cache_destroy(scene);
  final_image_cache_destroy(scene);
  preview_cache_destroy(scene);
  channels_free(&ed->channels);

  MEM_delete(ed);

  scene->ed = nullptr;
}

static void seq_new_fix_links_recursive(Strip *strip, Map<Strip *, Strip *> strip_map)
{
  if (strip->is_effect()) {
    strip->input1 = strip_map.lookup_default(strip->input1, strip->input1);
    strip->input2 = strip_map.lookup_default(strip->input2, strip->input2);
  }

  for (StripModifierData &smd : strip->modifiers) {
    smd.mask_strip = strip_map.lookup_default(smd.mask_strip, smd.mask_strip);
  }

  if (is_strip_connected(strip)) {
    for (StripConnection &con : strip->connections) {
      con.strip_ref = strip_map.lookup_default(con.strip_ref, con.strip_ref);
    }
  }

  if (strip->type == STRIP_TYPE_META) {
    for (Strip &strip_n : strip->seqbase) {
      seq_new_fix_links_recursive(&strip_n, strip_map);
    }
  }
}

SequencerToolSettings *tool_settings_init()
{
  SequencerToolSettings *tool_settings = MEM_new<SequencerToolSettings>("Sequencer tool settings");
  tool_settings->fit_method = SEQ_SCALE_TO_FIT;
  tool_settings->snap_mode = SEQ_SNAP_TO_STRIPS | SEQ_SNAP_TO_CURRENT_FRAME |
                             SEQ_SNAP_TO_STRIP_HOLD | SEQ_SNAP_TO_MARKERS | SEQ_SNAP_TO_RETIMING |
                             SEQ_SNAP_TO_PREVIEW_BORDERS | SEQ_SNAP_TO_PREVIEW_CENTER |
                             SEQ_SNAP_TO_STRIPS_PREVIEW | SEQ_SNAP_TO_FRAME_RANGE;
  tool_settings->snap_flag = SEQ_SNAP_TO_ALL_CHANNEL_STRIPS;
  tool_settings->snap_distance = 15;
  tool_settings->overlap_mode = SEQ_OVERLAP_SHUFFLE;
  tool_settings->pivot_point = V3D_AROUND_LOCAL_ORIGINS;

  return tool_settings;
}

SequencerToolSettings *tool_settings_ensure(Scene *scene)
{
  SequencerToolSettings *tool_settings = scene->toolsettings->sequencer_tool_settings;
  if (tool_settings == nullptr) {
    scene->toolsettings->sequencer_tool_settings = tool_settings_init();
    tool_settings = scene->toolsettings->sequencer_tool_settings;
  }

  return tool_settings;
}

void tool_settings_free(SequencerToolSettings *tool_settings)
{
  MEM_delete(tool_settings);
}

eSeqImageFitMethod tool_settings_fit_method_get(Scene *scene)
{
  const SequencerToolSettings *tool_settings = tool_settings_ensure(scene);
  return eSeqImageFitMethod(tool_settings->fit_method);
}

short tool_settings_snap_mode_get(Scene *scene)
{
  const SequencerToolSettings *tool_settings = tool_settings_ensure(scene);
  return tool_settings->snap_mode;
}

short tool_settings_snap_flag_get(Scene *scene)
{
  const SequencerToolSettings *tool_settings = tool_settings_ensure(scene);
  return tool_settings->snap_flag;
}

int tool_settings_snap_distance_get(Scene *scene)
{
  const SequencerToolSettings *tool_settings = tool_settings_ensure(scene);
  return tool_settings->snap_distance;
}

void tool_settings_fit_method_set(Scene *scene, eSeqImageFitMethod fit_method)
{
  SequencerToolSettings *tool_settings = tool_settings_ensure(scene);
  tool_settings->fit_method = fit_method;
}

eSeqOverlapMode tool_settings_overlap_mode_get(Scene *scene)
{
  const SequencerToolSettings *tool_settings = tool_settings_ensure(scene);
  return eSeqOverlapMode(tool_settings->overlap_mode);
}

int tool_settings_pivot_point_get(Scene *scene)
{
  const SequencerToolSettings *tool_settings = tool_settings_ensure(scene);
  return tool_settings->pivot_point;
}

ListBaseT<Strip> *active_seqbase_get(const Editing *ed)
{
  return ed ? ed->current_strips() : nullptr;
}

static MetaStack *seq_meta_stack_alloc(const Scene *scene, Strip *strip_meta)
{
  Editing *ed = editing_get(scene);

  MetaStack *ms = MEM_new<MetaStack>("metastack");
  BLI_addhead(&ed->metastack, ms);
  ms->parent_strip = strip_meta;

  /* Reference to previously displayed timeline data. */
  ms->old_strip = lookup_meta_by_strip(ed, strip_meta);

  ms->disp_range[0] = ms->parent_strip->left_handle();
  ms->disp_range[1] = ms->parent_strip->right_handle(scene);
  return ms;
}

MetaStack *meta_stack_active_get(const Editing *ed)
{
  if (ed == nullptr) {
    return nullptr;
  }

  return static_cast<MetaStack *>(ed->metastack.last);
}

void meta_stack_set(const Scene *scene, Strip *dst)
{
  Editing *ed = editing_get(scene);
  /* Clear metastack */
  ed->metastack.free_no_destruct();

  if (dst != nullptr) {
    /* Allocate meta stack in a way, that represents meta hierarchy in timeline. */
    seq_meta_stack_alloc(scene, dst);
    Strip *meta_parent = dst;
    while ((meta_parent = lookup_meta_by_strip(ed, meta_parent))) {
      seq_meta_stack_alloc(scene, meta_parent);
    }

    ed->current_meta_strip = dst;
  }
  else {
    ed->current_meta_strip = nullptr;
  }
}

Strip *meta_stack_pop(Editing *ed)
{
  MetaStack *ms = meta_stack_active_get(ed);
  Strip *meta_parent = ms->parent_strip;
  ed->current_meta_strip = ms->old_strip;
  BLI_remlink(&ed->metastack, ms);
  MEM_delete(ms);
  return meta_parent;
}

/** \} */

/* -------------------------------------------------------------------- */
/** \name Duplicate Functions
 * \{ */

struct StripDuplicateContext {
  Main *bmain;
  const Scene *scene_src;
  Scene *scene_dst;
  /* Mapping from original strips to their duplicates, for fixing effect/modifier/connection links
   * in `seq_duplicate_postprocess`. */
  Map<Strip *, Strip *> strip_map;
  StripDuplicate dupe_flag;
  int copy_flag;

  /* Sources of newly created datablocks when duplicating strips.
   * Their duplicates are processed with `seq_duplicate_postprocess`. */
  Set<Scene *> scenes;
  Set<Object *> scene_cameras;
  Set<MovieClip *> movieclips;
  Set<Mask *> masks;
};

static StripDuplicateContext strip_duplicate_context_get(
    Main *bmain, const Scene *scene_src, Scene *scene_dst, StripDuplicate dupe_flag, int copy_flag)
{
  StripDuplicateContext ctx;
  ctx.bmain = bmain;
  ctx.scene_src = scene_src;
  ctx.scene_dst = scene_dst;
  ctx.dupe_flag = dupe_flag;
  ctx.copy_flag = copy_flag;

  return ctx;
}

static void seq_duplicate_postprocess(StripDuplicateContext &ctx)
{
  const int remap_flag = ID_REMAP_FORCE_OBDATA_IN_EDITMODE | ID_REMAP_SKIP_USER_CLEAR;

  if (flag_is_set(ctx.dupe_flag, StripDuplicate::Data)) {
    /* Remapping newids in Scenes will usually trigger a view_layers/collections resync after each
     * scene. Besides performances considerations, this is also bad because it means some
     * not-yet-remapped scenes will get their view-layer updated while still referencing old
     * (source) collections, objects etc. This can e.g. lead to losing the active object in the
     * duplicated scenes.
     *
     * So instead, prevent any resync until all new IDs have been remapped. */
    BKE_layer_collection_resync_forbid(*ctx.bmain);

    /* Newly created data-blocks may reference IDs that themselves have also been duplicated in the
     * "current duplication". E.g. a scene may have a custom property that refers to itself; when
     * it is duplicated, we should ensure that these references are properly remapped.
     *
     * NOTE: Some of these IDs may be processed as part of dependencies when relinking another ID,
     * so they may have already been remapped, and their `newid` pointer, reset to nullptr. */
    for (Scene *scene_src : ctx.scenes) {
      BLI_assert(scene_src);
      if (scene_src->id.newid) {
        BKE_libblock_relink_to_newid(ctx.bmain, scene_src->id.newid, remap_flag);
      }
    }
    for (Object *scene_camera_src : ctx.scene_cameras) {
      BLI_assert(scene_camera_src);
      if (scene_camera_src->id.newid) {
        BKE_libblock_relink_to_newid(ctx.bmain, scene_camera_src->id.newid, remap_flag);
      }
    }
    for (MovieClip *movieclip_src : ctx.movieclips) {
      BLI_assert(movieclip_src);
      if (movieclip_src->id.newid) {
        BKE_libblock_relink_to_newid(ctx.bmain, movieclip_src->id.newid, remap_flag);
      }
    }
    for (Mask *mask_src : ctx.masks) {
      BLI_assert(mask_src);
      if (mask_src->id.newid) {
        BKE_libblock_relink_to_newid(ctx.bmain, mask_src->id.newid, remap_flag);
      }
    }

    BKE_layer_collection_resync_allow(*ctx.bmain);

    if (ctx.bmain != nullptr) {
#ifndef NDEBUG
      /* Calls to `BKE_libblock_relink_to_newid` above are supposed to have cleared all these
       * flags.
       */
      ID *id_iter;
      FOREACH_MAIN_ID_BEGIN (ctx.bmain, id_iter) {
        BLI_assert((id_iter->tag & ID_TAG_NEW) == 0);
      }
      FOREACH_MAIN_ID_END;
#endif

      /* Clear temporary `newid` for potentially copied datablocks (scene, scene cameras, mask, and
       * movieclip) to indicate that we have finished processing them. */
      BKE_main_id_newptr_and_tag_clear(ctx.bmain);

      BKE_main_collection_sync(ctx.bmain);
    }
  }
  else {
    BLI_assert(ctx.scenes.is_empty());
    BLI_assert(ctx.scene_cameras.is_empty());
    BLI_assert(ctx.movieclips.is_empty());
    BLI_assert(ctx.masks.is_empty());
  }

  /* Fix effect, modifier, and connected strip links. */
  for (Strip *strip_new : ctx.strip_map.values()) {
    seq_new_fix_links_recursive(strip_new, ctx.strip_map);
  }

  /* One-way connections must be cut after all connections are remapped above. */
  for (Strip *strip_new : ctx.strip_map.values()) {
    if (is_strip_connected(strip_new)) {
      cut_one_way_connections(strip_new);
    }
  }
}

static Strip *strip_duplicate(StripDuplicateContext &ctx,
                              ListBaseT<Strip> *seqbase_dst,
                              Strip *strip)
{
  Strip *strip_new = MEM_new<Strip>(__func__, *strip);
  strip_new->scene_view_layer_name = BLI_strdup_null(strip->scene_view_layer_name);
  strip_new->runtime = MEM_new<StripRuntime>(__func__);
  strip_new->runtime->flag = strip->runtime->flag;

  ctx.strip_map.add(strip, strip_new);

  if ((ctx.copy_flag & LIB_ID_CREATE_NO_MAIN) == 0) {
    relations_session_uid_generate(strip_new);
  }
  else {
    strip_new->runtime->session_uid = strip->runtime->session_uid;
  }

  strip_new->data = MEM_dupalloc(strip->data);

  strip_new->stereo3d_format = MEM_dupalloc(strip->stereo3d_format);

  /* XXX: add F-Curve duplication stuff? */

  if (strip->data->crop) {
    strip_new->data->crop = MEM_dupalloc(strip->data->crop);
  }

  if (strip->data->transform) {
    strip_new->data->transform = MEM_dupalloc(strip->data->transform);
  }

  if (strip->data->proxy) {
    strip_new->data->proxy = MEM_dupalloc(strip->data->proxy);
    strip_new->data->proxy->anim = nullptr;
  }

  if (strip->prop) {
    strip_new->prop = IDP_CopyProperty_ex(strip->prop, ctx.copy_flag);
  }
  if (strip->system_properties) {
    strip_new->system_properties = IDP_CopyProperty_ex(strip->system_properties, ctx.copy_flag);
  }

  if (strip_new->modifiers.first) {
    strip_new->modifiers.clear_no_delete();

    modifier_list_copy(strip_new, strip, ctx.copy_flag);
  }
  BLI_assert(modifier_persistent_uids_are_valid(*strip));

  if (is_strip_connected(strip)) {
    strip_new->connections.clear_no_delete();
    connections_duplicate(&strip_new->connections, &strip->connections);
  }

  if (strip->type == STRIP_TYPE_META) {
    strip_new->data->stripdata = nullptr;

    strip_new->seqbase.clear_no_delete();
    strip_new->channels.clear_no_delete();
    channels_duplicate(&strip_new->channels, &strip->channels);
  }
  else if (strip->type == STRIP_TYPE_SCENE) {
    if (flag_is_set(ctx.dupe_flag, StripDuplicate::Data) && strip_new->scene != nullptr) {
      Scene *scene_old = strip_new->scene;
      ctx.scenes.add(scene_old);

      Object *scene_camera_old = strip_new->scene_camera;
      if (scene_camera_old) {
        ctx.scene_cameras.add(scene_camera_old);
      }

      strip_new->scene = BKE_scene_duplicate(ctx.bmain,
                                             scene_old,
                                             SCE_COPY_FULL,
                                             eDupli_ID_Flags(U.dupflag | USER_DUP_OBJECT),
                                             LIB_ID_DUPLICATE_IS_ROOT_ID |
                                                 LIB_ID_DUPLICATE_IS_SUBPROCESS);

      if (scene_camera_old && scene_camera_old->id.newid) {
        strip_new->scene_camera = blender::id_cast<Object *>(scene_camera_old->id.newid);
      }
    }
    strip_new->data->stripdata = nullptr;
    if (strip->runtime->scene_sound) {
      strip_new->runtime->scene_sound = BKE_sound_scene_add_scene_sound(ctx.scene_dst, strip_new);
    }
  }
  else if (strip->type == STRIP_TYPE_MOVIECLIP) {
    if (flag_is_set(ctx.dupe_flag, StripDuplicate::Data) && strip_new->clip != nullptr) {
      MovieClip *clip_old = strip_new->clip;
      ctx.movieclips.add(clip_old);
      strip_new->clip = reinterpret_cast<MovieClip *>(BKE_id_copy_for_duplicate(
          ctx.bmain, reinterpret_cast<ID *>(clip_old), USER_DUP_LINKED_ID, LIB_ID_COPY_DEFAULT));
    }
    if ((ctx.copy_flag & LIB_ID_CREATE_NO_USER_REFCOUNT) == 0) {
      id_us_plus(&strip_new->clip->id);
    }
  }
  else if (strip->type == STRIP_TYPE_MASK) {
    if (flag_is_set(ctx.dupe_flag, StripDuplicate::Data) && strip_new->mask != nullptr) {
      Mask *mask_old = strip_new->mask;
      ctx.masks.add(mask_old);
      strip_new->mask = reinterpret_cast<Mask *>(BKE_id_copy_for_duplicate(
          ctx.bmain, reinterpret_cast<ID *>(mask_old), USER_DUP_LINKED_ID, LIB_ID_COPY_DEFAULT));
    }
    if ((ctx.copy_flag & LIB_ID_CREATE_NO_USER_REFCOUNT) == 0) {
      id_us_plus(&strip_new->mask->id);
    }
  }
  else if (strip->type == STRIP_TYPE_MOVIE) {
    strip_new->data->stripdata = MEM_dupalloc(strip->data->stripdata);
  }
  else if (strip->type == STRIP_TYPE_SOUND) {
    strip_new->data->stripdata = MEM_dupalloc(strip->data->stripdata);
    strip_new->runtime->scene_sound = nullptr;
    strip_new->runtime->sound_time_stretch = nullptr;
    if ((ctx.copy_flag & LIB_ID_CREATE_NO_USER_REFCOUNT) == 0) {
      id_us_plus(id_cast<ID *>(strip_new->sound));
    }
  }
  else if (strip->type == STRIP_TYPE_IMAGE) {
    strip_new->data->stripdata = MEM_dupalloc(strip->data->stripdata);
  }
  else if (strip->is_effect()) {
    EffectHandle sh = strip_effect_handle_get(strip);
    if (sh.copy) {
      sh.copy(strip_new, strip, ctx.copy_flag);
    }

    strip_new->data->stripdata = nullptr;
  }
  else {
    /* sequence type not handled in duplicate! Expect a crash now... */
    BLI_assert_unreachable();
  }

  /* When using StripDuplicate::UniqueName, it is mandatory to add new strips in relevant container
   * (scene or meta's one), *before* checking for unique names. Otherwise the meta's list is empty
   * and hence we miss all sequencer strips in that meta that have already been duplicated,
   * (see #55668). Note that unique name check itself could be done at a later step in calling
   * code, once all sequencer strips have been duplicated (that was first, simpler solution),
   * but then handling of animation data will be broken (see #60194). */
  if (seqbase_dst != nullptr) {
    BLI_addtail(seqbase_dst, strip_new);
  }

  if (ctx.scene_src == ctx.scene_dst) {
    if (flag_is_set(ctx.dupe_flag, StripDuplicate::UniqueName)) {
      strip_unique_name_set(ctx.scene_dst, &ctx.scene_dst->ed->seqbase, strip_new);
    }
  }

  if (strip->retiming_keys != nullptr) {
    strip_new->retiming_keys = MEM_dupalloc(strip->retiming_keys);
    strip_new->retiming_keys_num = strip->retiming_keys_num;
  }

  return strip_new;
}

static Strip *strip_duplicate_recursive_impl(StripDuplicateContext &ctx,
                                             ListBaseT<Strip> *seqbase_dst,
                                             Strip *strip)
{
  Strip *strip_new = strip_duplicate(ctx, seqbase_dst, strip);
  if (strip->type == STRIP_TYPE_META) {
    for (Strip &strip_child : strip->seqbase) {
      strip_duplicate_recursive_impl(ctx, &strip_new->seqbase, &strip_child);
    }
  }
  return strip_new;
}

Strip *strip_duplicate_recursive(Main *bmain,
                                 const Scene *scene_src,
                                 Scene *scene_dst,
                                 ListBaseT<Strip> *seqbase_dst,
                                 Strip *strip,
                                 const StripDuplicate dupe_flag)
{
  StripDuplicateContext ctx = strip_duplicate_context_get(
      bmain, scene_src, scene_dst, dupe_flag, 0);

  Strip *strip_new = strip_duplicate_recursive_impl(ctx, seqbase_dst, strip);

  seq_duplicate_postprocess(ctx);

  return strip_new;
}

static void seqbase_duplicate_recursive_impl(StripDuplicateContext &ctx,
                                             ListBaseT<Strip> *seqbase_dst,
                                             const ListBaseT<Strip> *seqbase_src)
{
  for (Strip &strip : *seqbase_src) {
    if ((strip.flag & SEQ_SELECT) == 0 && !flag_is_set(ctx.dupe_flag, StripDuplicate::All)) {
      continue;
    }

    Strip *strip_new = strip_duplicate(ctx, seqbase_dst, &strip);
    BLI_assert(strip_new != nullptr);

    if (strip.type == STRIP_TYPE_META) {
      const StripDuplicate dupe_flag_restore = ctx.dupe_flag;
      /* Always duplicate all strip children inside a selected metastrip. */
      ctx.dupe_flag |= StripDuplicate::All;
      seqbase_duplicate_recursive_impl(ctx, &strip_new->seqbase, &strip.seqbase);
      ctx.dupe_flag = dupe_flag_restore;
    }
  }
}

void seqbase_duplicate_recursive(Main *bmain,
                                 const Scene *scene_src,
                                 Scene *scene_dst,
                                 ListBaseT<Strip> *seqbase_dst,
                                 const ListBaseT<Strip> *seqbase_src,
                                 const StripDuplicate dupe_flag,
                                 const int copy_flag)
{
  StripDuplicateContext ctx = strip_duplicate_context_get(
      bmain, scene_src, scene_dst, dupe_flag, copy_flag);

  seqbase_duplicate_recursive_impl(ctx, seqbase_dst, seqbase_src);

  seq_duplicate_postprocess(ctx);
}

bool is_valid_strip_channel(const Strip *strip)
{
  return strip->channel >= 1 && strip->channel <= MAX_CHANNELS;
}

SequencerToolSettings *tool_settings_copy(SequencerToolSettings *tool_settings)
{
  SequencerToolSettings *tool_settings_copy = static_cast<SequencerToolSettings *>(
      MEM_dupalloc(tool_settings));
  return tool_settings_copy;
}

/** \} */

static bool strip_write_data_cb(Strip *strip, void *userdata)
{
  BlendWriter *writer = static_cast<BlendWriter *>(userdata);
  writer->write_struct(strip);
  writer->write_string(strip->scene_view_layer_name);
  if (strip->data) {
    /* TODO this doesn't depend on the `Strip` data to be present? */
    if (strip->effectdata) {
      switch (strip->type) {
        case STRIP_TYPE_COLOR:
          writer->write_struct_cast<SolidColorVars>(strip->effectdata);
          break;
        case STRIP_TYPE_SPEED:
          writer->write_struct_cast<SpeedControlVars>(strip->effectdata);
          break;
        case STRIP_TYPE_WIPE:
          writer->write_struct_cast<WipeVars>(strip->effectdata);
          break;
        case STRIP_TYPE_GLOW:
          writer->write_struct_cast<GlowVars>(strip->effectdata);
          break;
        case STRIP_TYPE_GAUSSIAN_BLUR:
          writer->write_struct_cast<GaussianBlurVars>(strip->effectdata);
          break;
        case STRIP_TYPE_TEXT: {
          TextVars *text = static_cast<TextVars *>(strip->effectdata);
          if (!BLO_write_is_undo(writer)) {
            /* Copy current text into legacy buffer. */
            STRNCPY_UTF8(text->text_legacy, text->text_ptr);
          }
          writer->write_struct(text);
          writer->write_string(text->text_ptr);
        } break;
        case STRIP_TYPE_COLORMIX:
          writer->write_struct_cast<ColorMixVars>(strip->effectdata);
          break;
        case STRIP_TYPE_COMPOSITOR:
          writer->write_struct_cast<CompositorEffectVars>(strip->effectdata);
          break;
        default:
          break;
      }
    }

    writer->write_struct(strip->stereo3d_format);

    StripData *data = strip->data;
    writer->write_struct(data);
    if (data->crop) {
      writer->write_struct(data->crop);
    }
    if (data->transform) {
      writer->write_struct(data->transform);
    }
    if (data->proxy) {
      writer->write_struct(data->proxy);
    }
    if (strip->type == STRIP_TYPE_IMAGE) {
      writer->write_struct_array(MEM_allocN_len(data->stripdata) / sizeof(StripElem),
                                 data->stripdata);
    }
    else if (ELEM(strip->type, STRIP_TYPE_MOVIE, STRIP_TYPE_SOUND)) {
      writer->write_struct(data->stripdata);
    }
  }

  if (strip->prop) {
    IDP_BlendWrite(writer, strip->prop);
  }
  if (strip->system_properties) {
    IDP_BlendWrite(writer, strip->system_properties);
  }

  modifier_blend_write(writer, &strip->modifiers);

  for (SeqTimelineChannel &channel : strip->channels) {
    writer->write_struct(&channel);
  }

  for (StripConnection &con : strip->connections) {
    writer->write_struct(&con);
  }

  if (strip->retiming_keys != nullptr) {
    int size = retiming_keys_count(strip);
    writer->write_struct_array(size, strip->retiming_keys);
  }

  return true;
}

void blend_write(BlendWriter *writer, ListBaseT<Strip> *seqbase)
{
  foreach_strip(seqbase, strip_write_data_cb, writer);
}

static bool strip_read_data_cb(Strip *strip, void *user_data)
{
  BlendDataReader *reader = static_cast<BlendDataReader *>(user_data);

  strip->runtime = MEM_new<StripRuntime>(__func__);
  /* Do as early as possible, so that other parts of reading can rely on valid session UID. */
  relations_session_uid_generate(strip);

  BLO_read_struct(reader, Strip, &strip->input1);
  BLO_read_struct(reader, Strip, &strip->input2);
  BLO_read_string(reader, &strip->scene_view_layer_name);

  if (strip->effectdata) {
    switch (strip->type) {
      case STRIP_TYPE_COLOR:
        BLO_read_struct_nonnull(reader, SolidColorVars, &strip->effectdata);
        break;
      case STRIP_TYPE_SPEED: {
        if (BLO_read_struct_nonnull(reader, SpeedControlVars, &strip->effectdata)) {
          SpeedControlVars *speed = static_cast<SpeedControlVars *>(strip->effectdata);
          speed->frameMap = nullptr;
        }
      } break;
      case STRIP_TYPE_WIPE:
        BLO_read_struct_nonnull(reader, WipeVars, &strip->effectdata);
        break;
      case STRIP_TYPE_GLOW:
        BLO_read_struct_nonnull(reader, GlowVars, &strip->effectdata);
        break;
      case STRIP_TYPE_TRANSFORM_LEGACY:
        BLO_read_struct_nonnull(reader, TransformVarsLegacy, &strip->effectdata);
        break;
      case STRIP_TYPE_GAUSSIAN_BLUR:
        BLO_read_struct_nonnull(reader, GaussianBlurVars, &strip->effectdata);
        break;
      case STRIP_TYPE_TEXT: {
        if (BLO_read_struct_nonnull(reader, TextVars, &strip->effectdata)) {
          TextVars *text = static_cast<TextVars *>(strip->effectdata);
          BLO_read_string(reader, &text->text_ptr);
          text->text_len_bytes = text->text_ptr ? strlen(text->text_ptr) : 0;
          text->text_blf_id = STRIP_FONT_NOT_LOADED;
          text->runtime = nullptr;
        }
      } break;
      case STRIP_TYPE_COLORMIX:
        BLO_read_struct_nonnull(reader, ColorMixVars, &strip->effectdata);
        break;
      case STRIP_TYPE_COMPOSITOR:
        BLO_read_struct_nonnull(reader, CompositorEffectVars, &strip->effectdata);
        break;
      default:
        BLI_assert_unreachable();
        strip->effectdata = nullptr;
        break;
    }
  }

  BLO_read_struct(reader, Stereo3dFormat, &strip->stereo3d_format);

  BLO_read_struct(reader, IDProperty, &strip->prop);
  IDP_BlendDataRead(reader, &strip->prop);
  BLO_read_struct(reader, IDProperty, &strip->system_properties);
  IDP_BlendDataRead(reader, &strip->system_properties);

  BLO_read_struct(reader, StripData, &strip->data);
  if (strip->data) {
    /* `STRIP_TYPE_SOUND_HD` case needs to be kept here, for backward compatibility. */
    if (ELEM(strip->type,
             STRIP_TYPE_IMAGE,
             STRIP_TYPE_MOVIE,
             STRIP_TYPE_SOUND,
             STRIP_TYPE_SOUND_HD))
    {
      /* FIXME In #STRIP_TYPE_IMAGE case, there is currently no available information about the
       * length of the stored array of #StripElem.
       *
       * This is 'not a problem' because the reading code only checks that the loaded buffer is at
       * least large enough for the requested data (here a single #StripElem item), and always
       * assign the whole read memory (without any truncating). But relying on this behavior is
       * weak and should be addressed. */
      BLO_read_struct(reader, StripElem, &strip->data->stripdata);
    }
    else {
      strip->data->stripdata = nullptr;
    }
    BLO_read_struct(reader, StripCrop, &strip->data->crop);
    BLO_read_struct(reader, StripTransform, &strip->data->transform);
    BLO_read_struct(reader, StripProxy, &strip->data->proxy);
    if (strip->data->proxy) {
      strip->data->proxy->anim = nullptr;
    }
    else if (strip->flag & SEQ_USE_PROXY) {
      proxy_set(strip, true);
    }

    /* need to load color balance to it could be converted to modifier */
    BLO_read_struct(reader, StripColorBalance, &strip->data->color_balance_legacy);
  }

  modifier_blend_read_data(reader, &strip->modifiers);

  BLO_read_struct_list(reader, StripConnection, &strip->connections);
  for (StripConnection &con : strip->connections) {
    if (con.strip_ref) {
      BLO_read_struct(reader, Strip, &con.strip_ref);
    }
  }

  BLO_read_struct_list(reader, SeqTimelineChannel, &strip->channels);

  if (strip->retiming_keys != nullptr) {
    if (!BLO_read_array(reader, &strip->retiming_keys, retiming_keys_count(strip))) {
      strip->retiming_keys_num = 0;
    }
  }

  return true;
}
void blend_read(BlendDataReader *reader, ListBaseT<Strip> *seqbase)
{
  foreach_strip(seqbase, strip_read_data_cb, reader);
}

static bool strip_doversion_250_sound_proxy_update_cb(Strip *strip, void *user_data)
{
  Main *bmain = static_cast<Main *>(user_data);
  if (strip->type == STRIP_TYPE_SOUND_HD) {
    char filepath_abs[FILE_MAX];
    BLI_path_join(filepath_abs,
                  sizeof(filepath_abs),
                  strip->data->dirpath,
                  strip->data->stripdata->filename);
    BLI_path_abs(filepath_abs, BKE_main_blendfile_path(bmain));
    strip->sound = BKE_sound_new_file(bmain, filepath_abs);
    strip->type = STRIP_TYPE_SOUND;
  }
  return true;
}

void doversion_250_sound_proxy_update(Main *bmain, Editing *ed)
{
  foreach_strip(&ed->seqbase, strip_doversion_250_sound_proxy_update_cb, bmain);
}

/* Depsgraph update functions. */

static bool seq_mute_sound_strips_cb(Strip *strip, void *user_data)
{
  Scene *scene = static_cast<Scene *>(user_data);
  strip->runtime->remove_scene_sound(scene);
  strip->runtime->clear_sound_time_stretch();
  return true;
}

/* Adds sound of strip to the `scene->sound_scene` - "sound timeline". */
static void strip_update_mix_sounds(Scene *scene, Strip *strip)
{
  if (strip->runtime->scene_sound != nullptr) {
    return;
  }

  if (strip->sound != nullptr) {
    /* Adds `strip->sound->playback_handle` to `scene->sound_scene` */
    strip->runtime->scene_sound = BKE_sound_add_scene_sound(scene, strip);
  }
  else if (strip->type == STRIP_TYPE_SCENE && strip->scene != nullptr) {
    /* Adds `strip->scene->sound_scene` to `scene->sound_scene`. */
    BKE_sound_ensure_scene(strip->scene);
    strip->runtime->scene_sound = BKE_sound_scene_add_scene_sound(scene, strip);
  }
}

static void strip_update_sound_properties(const Scene *scene, const Strip *strip)
{
  const Strip *meta = lookup_meta_by_strip(editing_get(scene), strip);
  float output_volume = strip->volume;
  if (meta != nullptr) {
    output_volume *= meta->volume;
  }
  const int frame = BKE_scene_frame_get(scene);
  BKE_sound_set_scene_sound_volume_at_frame(strip->runtime->scene_sound,
                                            frame,
                                            output_volume,
                                            (strip->flag & SEQ_AUDIO_VOLUME_ANIMATED) != 0);
  retiming_sound_animation_data_set(scene, strip);
  BKE_sound_set_scene_sound_pan_at_frame(
      strip->runtime->scene_sound, frame, strip->pan, (strip->flag & SEQ_AUDIO_PAN_ANIMATED) != 0);
}

static void strip_update_sound_modifiers(Strip *strip)
{
  AUD_Sound sound_handle = BKE_sound_playback_handle_get(strip->sound);
  bool needs_update = false;
  int sound_modifiers_count = 0;

  for (StripModifierData &smd : strip->modifiers) {
    sound_handle = sound_modifier_recreator(strip, &smd, sound_handle, needs_update);
    sound_modifiers_count++;
  }

  /* Check if a modifier was removed. It is particularly needed when the last modifier is removed
   * and the `scene_sound` handle has to be updated but all the previous modifiers detect no change
   * and `needs_update` remains false. */
  if (strip->runtime->sound_modifiers_count != sound_modifiers_count) {
    needs_update = true;
    strip->runtime->sound_modifiers_count = sound_modifiers_count;
  }

  if (needs_update) {
    /* Assign modified sound back to `strip`. */
    BKE_sound_update_sequence_handle(strip->runtime->scene_sound, sound_handle);
  }
}

static bool must_update_strip_sound(Scene *scene, Strip *strip)
{
  return (scene->id.recalc & (ID_RECALC_AUDIO | ID_RECALC_SYNC_TO_EVAL)) != 0 ||
         (strip->sound->id.recalc & (ID_RECALC_AUDIO | ID_RECALC_SYNC_TO_EVAL)) != 0;
}

static void seq_update_sound_strips(Scene *scene, Strip *strip)
{
  if (strip->sound == nullptr || !must_update_strip_sound(scene, strip)) {
    return;
  }

  /* Ensure strip is playing correct sound. */
  if (strip->modifiers.is_empty()) {
    /* No modifiers: ensure we are playing the sound ID. However do not do this
     * if we are pitch correcting, as the proper playback handle will be assigned there.
     * Changing between original file sound and the pitch correction sound produces garbage
     * audio in renders. */
    if (strip->runtime->sound_time_stretch == nullptr) {
      BKE_sound_update_scene_sound(strip->runtime->scene_sound, strip->sound);
    }
  }
  else {
    /* Use Playback handle from sound ID as input for modifier stack. */
    strip_update_sound_modifiers(strip);
  }
}

static bool scene_sequencer_is_used(const Scene *scene, ListBaseT<Strip> *seqbase)
{
  bool sequencer_is_used = false;
  for (Strip &strip_iter : *seqbase) {
    if (strip_iter.scene == scene && (strip_iter.flag & SEQ_SCENE_STRIPS) != 0) {
      sequencer_is_used = true;
    }
    if (strip_iter.type == STRIP_TYPE_META) {
      sequencer_is_used |= scene_sequencer_is_used(scene, &strip_iter.seqbase);
    }
  }

  return sequencer_is_used;
}

static void seq_update_scene_strip_sound(const Scene *scene, Strip *strip)
{
  if (strip->type != STRIP_TYPE_SCENE || strip->scene == nullptr) {
    return;
  }

  /* Set `strip->scene` volume.
   * NOTE: Currently this doesn't work well, when this property is animated. Scene strip volume is
   * also controlled by `strip_update_sound_properties()` via `strip->volume` which works if
   * animated.
   *
   * Ideally, the entire `BKE_scene_update_sound()` will happen from a dependency graph, so
   * then it is no longer needed to do such manual forced updates. */
  BKE_sound_set_scene_volume(strip->scene, strip->scene->audio.volume);

  /* Mute sound when all scene strips using particular scene are not rendering sequencer strips. */
  bool sequencer_is_used = scene_sequencer_is_used(strip->scene, &scene->ed->seqbase);

  if (!sequencer_is_used && strip->scene->runtime->audio.sound_scene != nullptr &&
      strip->scene->ed != nullptr)
  {
    foreach_strip(&strip->scene->ed->seqbase, seq_mute_sound_strips_cb, strip->scene);
  }
}

static bool strip_sound_update_cb(Strip *strip, void *user_data)
{
  Scene *scene = static_cast<Scene *>(user_data);

  strip_update_mix_sounds(scene, strip);

  if (strip->runtime->scene_sound == nullptr) {
    return true;
  }

  seq_update_sound_strips(scene, strip);
  seq_update_scene_strip_sound(scene, strip);
  strip_update_sound_properties(scene, strip);
  return true;
}

void eval_strips(Depsgraph *depsgraph, Scene *scene, ListBaseT<Strip> *seqbase)
{
  DEG_debug_print_eval(depsgraph, __func__, scene->id.name, scene);

  /* Note: sequencer caches are stored on the original scene, not the evaluated copy. */
  relations_invalidate_temporary_animation_frame(DEG_get_original(scene));

  BKE_sound_ensure_scene(scene);

  foreach_strip(seqbase, strip_sound_update_cb, scene);

  edit_update_muting(scene->ed);
  sound_update_bounds_all(scene);
}

EditingRuntime::~EditingRuntime()
{
  MEM_delete(this->compositor_cache);
}

CompositorCache &EditingRuntime::ensure_compositor_cache()
{
  if (this->compositor_cache == nullptr) {
    this->compositor_cache = MEM_new<CompositorCache>(__func__);
  }
  return *this->compositor_cache;
}

}  // namespace seq

Editing::Editing()
{
  this->runtime = MEM_new<seq::EditingRuntime>(__func__);
}

Editing::~Editing()
{
  MEM_delete(this->runtime);
}

ListBaseT<Strip> *Editing::current_strips()
{
  if (this->current_meta_strip) {
    return &this->current_meta_strip->seqbase;
  }
  return &this->seqbase;
}

ListBaseT<Strip> *Editing::current_strips() const
{
  if (this->current_meta_strip) {
    return &this->current_meta_strip->seqbase;
  }
  /* NOTE: Const correctness is non-existent with ListBaseT anyway. */
  return &const_cast<ListBaseT<Strip> &>(this->seqbase);
}

ListBaseT<SeqTimelineChannel> *Editing::current_channels()
{
  if (this->current_meta_strip) {
    return &this->current_meta_strip->channels;
  }
  return &this->channels;
}

ListBaseT<SeqTimelineChannel> *Editing::current_channels() const
{
  if (this->current_meta_strip) {
    return &this->current_meta_strip->channels;
  }
  /* NOTE: Const correctness is non-existent with ListBaseT anyway. */
  return &const_cast<ListBaseT<SeqTimelineChannel> &>(this->channels);
}

bool Strip::is_effect() const
{
  return blender::seq::strip_type_is_effect(this->type);
}

int Strip::effect_num_inputs_get() const
{
  /* Compositor can have varying amount of inputs; return based on assigned inputs. */
  if (this->type == STRIP_TYPE_COMPOSITOR) {
    return this->input1 && this->input2 ? 2 : this->input1 ? 1 : 0;
  }
  return blender::seq::effect_type_get_min_num_inputs(this->type);
}

bool StripModifierData::is_type_sound() const
{
  return ELEM(
      this->type, eSeqModifierType_SoundEqualizer, eSeqModifierType_Echo, eSeqModifierType_Pitch);
}

}  // namespace blender
