sequencer_select.cc

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/* SPDX-FileCopyrightText: 2001-2002 NaN Holding BV. All rights reserved.
 *
 * SPDX-License-Identifier: GPL-2.0-or-later */

 
#include <cmath>
#include <cstdlib>
#include <cstring>
 
#include "MEM_guardedalloc.h"
 
#include "BLI_blenlib.h"
#include "BLI_ghash.h"
#include "BLI_math_geom.h"
#include "BLI_math_vector.h"
#include "BLI_math_vector_types.hh"
#include "BLI_utildefines.h"
 
#include "DNA_scene_types.h"
#include "DNA_space_types.h"
 
#include "BKE_context.hh"
#include "BKE_report.hh"
 
#include "WM_api.hh"
#include "WM_types.hh"
 
#include "RNA_define.hh"
 
#include "SEQ_channels.hh"
#include "SEQ_connect.hh"
#include "SEQ_effects.hh"
#include "SEQ_iterator.hh"
#include "SEQ_relations.hh"
#include "SEQ_retiming.hh"
#include "SEQ_select.hh"
#include "SEQ_sequencer.hh"
#include "SEQ_time.hh"
#include "SEQ_transform.hh"
 
/* For menu, popup, icons, etc. */
 
#include "ED_outliner.hh"
#include "ED_screen.hh"
#include "ED_select_utils.hh"
#include "ED_sequencer.hh"
 
#include "UI_view2d.hh"
 
/* Own include. */
#include "sequencer_intern.hh"
 
/* -------------------------------------------------------------------- */
 
class MouseCoords {
 public:
  blender::int2 region;
  blender::float2 view;
 
  MouseCoords(const View2D *v2d, int x, int y)
  {
    region[0] = x;
    region[1] = y;
    UI_view2d_region_to_view(v2d, x, y, &view[0], &view[1]);
  }
};
 
blender::VectorSet<Sequence *> all_strips_from_context(bContext *C)
{
  Scene *scene = CTX_data_scene(C);
  Editing *ed = SEQ_editing_get(scene);
  ListBase *seqbase = SEQ_active_seqbase_get(ed);
  ListBase *channels = SEQ_channels_displayed_get(ed);
 
  const bool is_preview = sequencer_view_has_preview_poll(C);
  if (is_preview) {
    return SEQ_query_rendered_strips(scene, channels, seqbase, scene->r.cfra, 0);
  }
 
  return SEQ_query_all_strips(seqbase);
}
 
blender::VectorSet<Sequence *> ED_sequencer_selected_strips_from_context(bContext *C)
{
  const Scene *scene = CTX_data_scene(C);
  Editing *ed = SEQ_editing_get(scene);
  ListBase *seqbase = SEQ_active_seqbase_get(ed);
  ListBase *channels = SEQ_channels_displayed_get(ed);
 
  const bool is_preview = sequencer_view_has_preview_poll(C);
 
  if (is_preview) {
    blender::VectorSet strips = SEQ_query_rendered_strips(
        scene, channels, seqbase, scene->r.cfra, 0);
    strips.remove_if([&](Sequence *seq) { return (seq->flag & SELECT) == 0; });
    return strips;
  }
 
  return SEQ_query_selected_strips(seqbase);
}
 
static void select_surrounding_handles(Scene *scene, Sequence *test) /* XXX BRING BACK */
{
  Sequence *neighbor;
 
  neighbor = find_neighboring_sequence(scene, test, SEQ_SIDE_LEFT, -1);
  if (neighbor) {
    /* Only select neighbor handle if matching handle from test seq is also selected,
     * or if neighbor was not selected at all up till now.
     * Otherwise, we get odd mismatch when shift-alt-rmb selecting neighbor strips... */
    if (!(neighbor->flag & SELECT) || (test->flag & SEQ_LEFTSEL)) {
      neighbor->flag |= SEQ_RIGHTSEL;
    }
    neighbor->flag |= SELECT;
    recurs_sel_seq(neighbor);
  }
  neighbor = find_neighboring_sequence(scene, test, SEQ_SIDE_RIGHT, -1);
  if (neighbor) {
    if (!(neighbor->flag & SELECT) || (test->flag & SEQ_RIGHTSEL)) { /* See comment above. */
      neighbor->flag |= SEQ_LEFTSEL;
    }
    neighbor->flag |= SELECT;
    recurs_sel_seq(neighbor);
  }
}
 
/* Used for mouse selection in SEQUENCER_OT_select. */
static void select_active_side(
    const Scene *scene, ListBase *seqbase, int sel_side, int channel, int frame)
{
 
  LISTBASE_FOREACH (Sequence *, seq, seqbase) {
    if (channel == seq->machine) {
      switch (sel_side) {
        case SEQ_SIDE_LEFT:
          if (frame > SEQ_time_left_handle_frame_get(scene, seq)) {
            seq->flag &= ~(SEQ_RIGHTSEL | SEQ_LEFTSEL);
            seq->flag |= SELECT;
          }
          break;
        case SEQ_SIDE_RIGHT:
          if (frame < SEQ_time_left_handle_frame_get(scene, seq)) {
            seq->flag &= ~(SEQ_RIGHTSEL | SEQ_LEFTSEL);
            seq->flag |= SELECT;
          }
          break;
        case SEQ_SIDE_BOTH:
          seq->flag &= ~(SEQ_RIGHTSEL | SEQ_LEFTSEL);
          seq->flag |= SELECT;
          break;
      }
    }
  }
}
 
/* Used for mouse selection in SEQUENCER_OT_select_side. */
static void select_active_side_range(const Scene *scene,
                                     ListBase *seqbase,
                                     const int sel_side,
                                     const int frame_ranges[SEQ_MAX_CHANNELS],
                                     const int frame_ignore)
{
  LISTBASE_FOREACH (Sequence *, seq, seqbase) {
    if (seq->machine < SEQ_MAX_CHANNELS) {
      const int frame = frame_ranges[seq->machine];
      if (frame == frame_ignore) {
        continue;
      }
      switch (sel_side) {
        case SEQ_SIDE_LEFT:
          if (frame > SEQ_time_left_handle_frame_get(scene, seq)) {
            seq->flag &= ~(SEQ_RIGHTSEL | SEQ_LEFTSEL);
            seq->flag |= SELECT;
          }
          break;
        case SEQ_SIDE_RIGHT:
          if (frame < SEQ_time_left_handle_frame_get(scene, seq)) {
            seq->flag &= ~(SEQ_RIGHTSEL | SEQ_LEFTSEL);
            seq->flag |= SELECT;
          }
          break;
        case SEQ_SIDE_BOTH:
          seq->flag &= ~(SEQ_RIGHTSEL | SEQ_LEFTSEL);
          seq->flag |= SELECT;
          break;
      }
    }
  }
}
 
/* Used alongside `select_linked_time` helper function in SEQUENCER_OT_select. */
static void select_linked_time_seq(const Scene *scene,
                                   const Sequence *seq_source,
                                   const eSeqHandle handle_clicked)
{
  ListBase *seqbase = SEQ_active_seqbase_get(scene->ed);
  int source_left = SEQ_time_left_handle_frame_get(scene, seq_source);
  int source_right = SEQ_time_right_handle_frame_get(scene, seq_source);
 
  LISTBASE_FOREACH (Sequence *, seq_dest, seqbase) {
    if (seq_source->machine != seq_dest->machine) {
      const bool left_match = (SEQ_time_left_handle_frame_get(scene, seq_dest) == source_left);
      const bool right_match = (SEQ_time_right_handle_frame_get(scene, seq_dest) == source_right);
 
      if (left_match && right_match) {
        /* Direct match, copy all selection settings. */
        seq_dest->flag &= ~(SEQ_ALLSEL);
        seq_dest->flag |= seq_source->flag & (SEQ_ALLSEL);
        recurs_sel_seq(seq_dest);
      }
      else if (left_match && handle_clicked == SEQ_HANDLE_LEFT) {
        seq_dest->flag &= ~(SELECT | SEQ_LEFTSEL);
        seq_dest->flag |= seq_source->flag & (SELECT | SEQ_LEFTSEL);
        recurs_sel_seq(seq_dest);
      }
      else if (right_match && handle_clicked == SEQ_HANDLE_RIGHT) {
        seq_dest->flag &= ~(SELECT | SEQ_RIGHTSEL);
        seq_dest->flag |= seq_source->flag & (SELECT | SEQ_RIGHTSEL);
        recurs_sel_seq(seq_dest);
      }
    }
  }
}
 
#if 0 /* BRING BACK */
void select_surround_from_last(Scene *scene)
{
  Sequence *seq = get_last_seq(scene);
 
  if (seq == nullptr) {
    return;
  }
 
  select_surrounding_handles(scene, seq);
}
#endif
 
void ED_sequencer_select_sequence_single(Scene *scene, Sequence *seq, bool deselect_all)
{
  Editing *ed = SEQ_editing_get(scene);
 
  if (deselect_all) {
    ED_sequencer_deselect_all(scene);
  }
 
  SEQ_select_active_set(scene, seq);
 
  if (ELEM(seq->type, SEQ_TYPE_IMAGE, SEQ_TYPE_MOVIE)) {
    if (seq->strip) {
      BLI_strncpy(ed->act_imagedir, seq->strip->dirpath, FILE_MAXDIR);
    }
  }
  else if (seq->type == SEQ_TYPE_SOUND_RAM) {
    if (seq->strip) {
      BLI_strncpy(ed->act_sounddir, seq->strip->dirpath, FILE_MAXDIR);
    }
  }
  seq->flag |= SELECT;
  recurs_sel_seq(seq);
}
 
void seq_rectf(const Scene *scene, const Sequence *seq, rctf *r_rect)
{
  r_rect->xmin = SEQ_time_left_handle_frame_get(scene, seq);
  r_rect->xmax = SEQ_time_right_handle_frame_get(scene, seq);
  r_rect->ymin = seq->machine + SEQ_STRIP_OFSBOTTOM;
  r_rect->ymax = seq->machine + SEQ_STRIP_OFSTOP;
}
 
Sequence *find_neighboring_sequence(Scene *scene, Sequence *test, int lr, int sel)
{
  /* sel: 0==unselected, 1==selected, -1==don't care. */
  Editing *ed = SEQ_editing_get(scene);
 
  if (ed == nullptr) {
    return nullptr;
  }
 
  if (sel > 0) {
    sel = SELECT;
  }
  LISTBASE_FOREACH (Sequence *, seq, ed->seqbasep) {
    if ((seq != test) && (test->machine == seq->machine) &&
        ((sel == -1) || (sel && (seq->flag & SELECT)) || (sel == 0 && (seq->flag & SELECT) == 0)))
    {
      switch (lr) {
        case SEQ_SIDE_LEFT:
          if (SEQ_time_left_handle_frame_get(scene, test) ==
              SEQ_time_right_handle_frame_get(scene, seq))
          {
            return seq;
          }
          break;
        case SEQ_SIDE_RIGHT:
          if (SEQ_time_right_handle_frame_get(scene, test) ==
              SEQ_time_left_handle_frame_get(scene, seq))
          {
            return seq;
          }
          break;
      }
    }
  }
  return nullptr;
}
 
Sequence *find_nearest_seq(const Scene *scene,
                           const View2D *v2d,
                           const int mval[2],
                           eSeqHandle *r_hand)
{
  Sequence *seq;
  Editing *ed = SEQ_editing_get(scene);
  float x, y;
  float pixelx;
  float handsize;
  float displen;
  *r_hand = SEQ_HANDLE_NONE;
 
  if (ed == nullptr) {
    return nullptr;
  }
 
  pixelx = BLI_rctf_size_x(&v2d->cur) / BLI_rcti_size_x(&v2d->mask);
 
  UI_view2d_region_to_view(v2d, mval[0], mval[1], &x, &y);
 
  seq = static_cast<Sequence *>(ed->seqbasep->first);
 
  while (seq) {
    if (seq->machine == int(y)) {
      /* Check for both normal strips, and strips that have been flipped horizontally. */
      if (((SEQ_time_left_handle_frame_get(scene, seq) <
            SEQ_time_right_handle_frame_get(scene, seq)) &&
           (SEQ_time_left_handle_frame_get(scene, seq) <= x &&
            SEQ_time_right_handle_frame_get(scene, seq) >= x)) ||
          ((SEQ_time_left_handle_frame_get(scene, seq) >
            SEQ_time_right_handle_frame_get(scene, seq)) &&
           (SEQ_time_left_handle_frame_get(scene, seq) >= x &&
            SEQ_time_right_handle_frame_get(scene, seq) <= x)))
      {
        if (SEQ_transform_sequence_can_be_translated(seq)) {
 
          /* Clamp handles to defined size in pixel space. */
          handsize = 4.0f * sequence_handle_size_get_clamped(scene, seq, pixelx);
          displen = float(abs(SEQ_time_left_handle_frame_get(scene, seq) -
                              SEQ_time_right_handle_frame_get(scene, seq)));
 
          /* Don't even try to grab the handles of small strips. */
          if (displen / pixelx > 16) {
 
            /* Set the max value to handle to 1/3 of the total len when its
             * less than 28. This is important because otherwise selecting
             * handles happens even when you click in the middle. */
            if ((displen / 3) < 30 * pixelx) {
              handsize = displen / 3;
            }
            else {
              CLAMP(handsize, 7 * pixelx, 30 * pixelx);
            }
 
            if (handsize + SEQ_time_left_handle_frame_get(scene, seq) >= x) {
              *r_hand = SEQ_HANDLE_LEFT;
            }
            else if (-handsize + SEQ_time_right_handle_frame_get(scene, seq) <= x) {
              *r_hand = SEQ_HANDLE_RIGHT;
            }
          }
        }
        return seq;
      }
    }
    seq = static_cast<Sequence *>(seq->next);
  }
  return nullptr;
}
 
#if 0
static void select_neighbor_from_last(Scene *scene, int lr)
{
  Sequence *seq = SEQ_select_active_get(scene);
  Sequence *neighbor;
  bool changed = false;
  if (seq) {
    neighbor = find_neighboring_sequence(scene, seq, lr, -1);
    if (neighbor) {
      switch (lr) {
        case SEQ_SIDE_LEFT:
          neighbor->flag |= SELECT;
          recurs_sel_seq(neighbor);
          neighbor->flag |= SEQ_RIGHTSEL;
          seq->flag |= SEQ_LEFTSEL;
          break;
        case SEQ_SIDE_RIGHT:
          neighbor->flag |= SELECT;
          recurs_sel_seq(neighbor);
          neighbor->flag |= SEQ_LEFTSEL;
          seq->flag |= SEQ_RIGHTSEL;
          break;
      }
      seq->flag |= SELECT;
      changed = true;
    }
  }
  if (changed) {
    /* Pass. */
  }
}
#endif
 
void recurs_sel_seq(Sequence *seq_meta)
{
  Sequence *seq;
  seq = static_cast<Sequence *>(seq_meta->seqbase.first);
 
  while (seq) {
 
    if (seq_meta->flag & (SEQ_LEFTSEL + SEQ_RIGHTSEL)) {
      seq->flag &= ~SEQ_ALLSEL;
    }
    else if (seq_meta->flag & SELECT) {
      seq->flag |= SELECT;
    }
    else {
      seq->flag &= ~SEQ_ALLSEL;
    }
 
    if (seq->seqbase.first) {
      recurs_sel_seq(seq);
    }
 
    seq = static_cast<Sequence *>(seq->next);
  }
}
 
static bool seq_point_image_isect(const Scene *scene, const Sequence *seq, float point[2])
{
  float seq_image_quad[4][2];
  SEQ_image_transform_final_quad_get(scene, seq, seq_image_quad);
  return isect_point_quad_v2(
      point, seq_image_quad[0], seq_image_quad[1], seq_image_quad[2], seq_image_quad[3]);
}
 
static void sequencer_select_do_updates(bContext *C, Scene *scene)
{
  ED_outliner_select_sync_from_sequence_tag(C);
  WM_event_add_notifier(C, NC_SCENE | ND_SEQUENCER | NA_SELECTED, scene);
}

 
/* -------------------------------------------------------------------- */
 
static int sequencer_de_select_all_exec(bContext *C, wmOperator *op)
{
  int action = RNA_enum_get(op->ptr, "action");
  Scene *scene = CTX_data_scene(C);
 
  if (sequencer_view_has_preview_poll(C) && !sequencer_view_preview_only_poll(C)) {
    return OPERATOR_CANCELLED;
  }
 
  if (sequencer_retiming_mode_is_active(C) && retiming_keys_can_be_displayed(CTX_wm_space_seq(C)))
  {
    return sequencer_retiming_select_all_exec(C, op);
  }
 
  blender::VectorSet strips = all_strips_from_context(C);
 
  if (action == SEL_TOGGLE) {
    action = SEL_SELECT;
    for (Sequence *seq : strips) {
      if (seq->flag & SEQ_ALLSEL) {
        action = SEL_DESELECT;
        break;
      }
    }
  }
 
  for (Sequence *seq : strips) {
    switch (action) {
      case SEL_SELECT:
        seq->flag &= ~(SEQ_LEFTSEL + SEQ_RIGHTSEL);
        seq->flag |= SELECT;
        break;
      case SEL_DESELECT:
        seq->flag &= ~SEQ_ALLSEL;
        break;
      case SEL_INVERT:
        if (seq->flag & SEQ_ALLSEL) {
          seq->flag &= ~SEQ_ALLSEL;
        }
        else {
          seq->flag &= ~(SEQ_LEFTSEL + SEQ_RIGHTSEL);
          seq->flag |= SELECT;
        }
        break;
    }
  }
  ED_outliner_select_sync_from_sequence_tag(C);
  WM_event_add_notifier(C, NC_SCENE | ND_SEQUENCER | NA_SELECTED, scene);
 
  return OPERATOR_FINISHED;
}
 
void SEQUENCER_OT_select_all(wmOperatorType *ot)
{
  /* Identifiers. */
  ot->name = "(De)select All";
  ot->idname = "SEQUENCER_OT_select_all";
  ot->description = "Select or deselect all strips";
 
  /* Api callbacks. */
  ot->exec = sequencer_de_select_all_exec;
  ot->poll = sequencer_edit_poll;
 
  /* Flags. */
  ot->flag = OPTYPE_UNDO;
 
  WM_operator_properties_select_all(ot);
}

 
/* -------------------------------------------------------------------- */
 
static int sequencer_select_inverse_exec(bContext *C, wmOperator * /*op*/)
{
  Scene *scene = CTX_data_scene(C);
 
  if (sequencer_view_has_preview_poll(C) && !sequencer_view_preview_only_poll(C)) {
    return OPERATOR_CANCELLED;
  }
 
  blender::VectorSet strips = all_strips_from_context(C);
 
  for (Sequence *seq : strips) {
    if (seq->flag & SELECT) {
      seq->flag &= ~SEQ_ALLSEL;
    }
    else {
      seq->flag &= ~(SEQ_LEFTSEL + SEQ_RIGHTSEL);
      seq->flag |= SELECT;
    }
  }
 
  ED_outliner_select_sync_from_sequence_tag(C);
  WM_event_add_notifier(C, NC_SCENE | ND_SEQUENCER | NA_SELECTED, scene);
 
  return OPERATOR_FINISHED;
}
 
void SEQUENCER_OT_select_inverse(wmOperatorType *ot)
{
  /* Identifiers. */
  ot->name = "Select Inverse";
  ot->idname = "SEQUENCER_OT_select_inverse";
  ot->description = "Select unselected strips";
 
  /* Api callbacks. */
  ot->exec = sequencer_select_inverse_exec;
  ot->poll = sequencer_edit_poll;
 
  /* Flags. */
  ot->flag = OPTYPE_UNDO;
}

 
/* -------------------------------------------------------------------- */
 
static void sequencer_select_set_active(Scene *scene, Sequence *seq)
{
  Editing *ed = SEQ_editing_get(scene);
 
  SEQ_select_active_set(scene, seq);
 
  if (ELEM(seq->type, SEQ_TYPE_IMAGE, SEQ_TYPE_MOVIE)) {
    if (seq->strip) {
      BLI_strncpy(ed->act_imagedir, seq->strip->dirpath, FILE_MAXDIR);
    }
  }
  else if (seq->type == SEQ_TYPE_SOUND_RAM) {
    if (seq->strip) {
      BLI_strncpy(ed->act_sounddir, seq->strip->dirpath, FILE_MAXDIR);
    }
  }
  recurs_sel_seq(seq);
}
 
static void sequencer_select_side_of_frame(const bContext *C,
                                           const View2D *v2d,
                                           const int mval[2],
                                           Scene *scene)
{
  Editing *ed = SEQ_editing_get(scene);
 
  const float x = UI_view2d_region_to_view_x(v2d, mval[0]);
  LISTBASE_FOREACH (Sequence *, seq_iter, SEQ_active_seqbase_get(ed)) {
    if (((x < scene->r.cfra) &&
         (SEQ_time_right_handle_frame_get(scene, seq_iter) <= scene->r.cfra)) ||
        ((x >= scene->r.cfra) &&
         (SEQ_time_left_handle_frame_get(scene, seq_iter) >= scene->r.cfra)))
    {
      /* Select left or right. */
      seq_iter->flag |= SELECT;
      recurs_sel_seq(seq_iter);
    }
  }
 
  {
    SpaceSeq *sseq = CTX_wm_space_seq(C);
    if (sseq && sseq->flag & SEQ_MARKER_TRANS) {
 
      LISTBASE_FOREACH (TimeMarker *, tmarker, &scene->markers) {
        if (((x < scene->r.cfra) && (tmarker->frame <= scene->r.cfra)) ||
            ((x >= scene->r.cfra) && (tmarker->frame >= scene->r.cfra)))
        {
          tmarker->flag |= SELECT;
        }
        else {
          tmarker->flag &= ~SELECT;
        }
      }
    }
  }
}
 
static void sequencer_select_linked_handle(const bContext *C,
                                           Sequence *seq,
                                           const eSeqHandle handle_clicked)
{
  Scene *scene = CTX_data_scene(C);
  Editing *ed = SEQ_editing_get(scene);
  if (!ELEM(handle_clicked, SEQ_HANDLE_LEFT, SEQ_HANDLE_RIGHT)) {
    /* First click selects the strip and its adjacent handles (if valid).
     * Second click selects the strip,
     * both of its handles and its adjacent handles (if valid). */
    const bool is_striponly_selected = ((seq->flag & SEQ_ALLSEL) == SELECT);
    seq->flag &= ~SEQ_ALLSEL;
    seq->flag |= is_striponly_selected ? SEQ_ALLSEL : SELECT;
    select_surrounding_handles(scene, seq);
  }
  else {
    /* Always select the strip under the cursor. */
    seq->flag |= SELECT;
 
    /* First click selects adjacent handles on that side.
     * Second click selects all strips in that direction.
     * If there are no adjacent strips, it just selects all in that direction.
     */
    const int sel_side = (handle_clicked == SEQ_HANDLE_LEFT) ? SEQ_SIDE_LEFT : SEQ_SIDE_RIGHT;
 
    Sequence *neighbor = find_neighboring_sequence(scene, seq, sel_side, -1);
    if (neighbor) {
      switch (sel_side) {
        case SEQ_SIDE_LEFT:
          if ((seq->flag & SEQ_LEFTSEL) && (neighbor->flag & SEQ_RIGHTSEL)) {
            seq->flag |= SELECT;
            select_active_side(scene,
                               ed->seqbasep,
                               SEQ_SIDE_LEFT,
                               seq->machine,
                               SEQ_time_left_handle_frame_get(scene, seq));
          }
          else {
            seq->flag |= SELECT;
            neighbor->flag |= SELECT;
            recurs_sel_seq(neighbor);
            neighbor->flag |= SEQ_RIGHTSEL;
            seq->flag |= SEQ_LEFTSEL;
          }
          break;
        case SEQ_SIDE_RIGHT:
          if ((seq->flag & SEQ_RIGHTSEL) && (neighbor->flag & SEQ_LEFTSEL)) {
            seq->flag |= SELECT;
            select_active_side(scene,
                               ed->seqbasep,
                               SEQ_SIDE_RIGHT,
                               seq->machine,
                               SEQ_time_left_handle_frame_get(scene, seq));
          }
          else {
            seq->flag |= SELECT;
            neighbor->flag |= SELECT;
            recurs_sel_seq(neighbor);
            neighbor->flag |= SEQ_LEFTSEL;
            seq->flag |= SEQ_RIGHTSEL;
          }
          break;
      }
    }
    else {
 
      select_active_side(
          scene, ed->seqbasep, sel_side, seq->machine, SEQ_time_left_handle_frame_get(scene, seq));
    }
  }
}

struct SeqSelect_Link {
  SeqSelect_Link *next, *prev;
  Sequence *seq;
  float center_dist_sq;
};
 
static int seq_sort_for_depth_select(const void *a, const void *b)
{
  const SeqSelect_Link *slink_a = static_cast<const SeqSelect_Link *>(a);
  const SeqSelect_Link *slink_b = static_cast<const SeqSelect_Link *>(b);
 
  /* Exactly overlapping strips, sort by machine (so the top-most is first). */
  if (slink_a->seq->machine < slink_b->seq->machine) {
    return 1;
  }
  if (slink_a->seq->machine > slink_b->seq->machine) {
    return -1;
  }
  return 0;
}
 
static int seq_sort_for_center_select(const void *a, const void *b)
{
  const SeqSelect_Link *slink_a = static_cast<const SeqSelect_Link *>(a);
  const SeqSelect_Link *slink_b = static_cast<const SeqSelect_Link *>(b);
  if (slink_a->center_dist_sq > slink_b->center_dist_sq) {
    return 1;
  }
  if (slink_a->center_dist_sq < slink_b->center_dist_sq) {
    return -1;
  }
 
  /* Exactly overlapping strips, use depth. */
  return seq_sort_for_depth_select(a, b);
}

static Sequence *seq_select_seq_from_preview(
    const bContext *C, const int mval[2], const bool toggle, const bool extend, const bool center)
{
  Scene *scene = CTX_data_scene(C);
  Editing *ed = SEQ_editing_get(scene);
  ListBase *seqbase = SEQ_active_seqbase_get(ed);
  ListBase *channels = SEQ_channels_displayed_get(ed);
  SpaceSeq *sseq = CTX_wm_space_seq(C);
  View2D *v2d = UI_view2d_fromcontext(C);
 
  float mouseco_view[2];
  UI_view2d_region_to_view(v2d, mval[0], mval[1], &mouseco_view[0], &mouseco_view[1]);
 
  /* Always update the coordinates (check extended after). */
  const bool use_cycle = (!WM_cursor_test_motion_and_update(mval) || extend || toggle);
 
  /* Allow strips this far from the closest center to be included.
   * This allows cycling over center points which are near enough
   * to overlapping from the users perspective. */
  const float center_dist_sq_max = square_f(75.0f * U.pixelsize);
  const float center_scale_px[2] = {
      UI_view2d_scale_get_x(v2d),
      UI_view2d_scale_get_y(v2d),
  };
 
  blender::VectorSet strips = SEQ_query_rendered_strips(
      scene, channels, seqbase, scene->r.cfra, sseq->chanshown);
 
  SeqSelect_Link *slink_active = nullptr;
  Sequence *seq_active = SEQ_select_active_get(scene);
  ListBase strips_ordered = {nullptr};
  for (Sequence *seq : strips) {
    bool isect = false;
    float center_dist_sq_test = 0.0f;
    if (center) {
      /* Detect overlapping center points (scaled by the zoom level). */
      float co[2];
      SEQ_image_transform_origin_offset_pixelspace_get(scene, seq, co);
      sub_v2_v2(co, mouseco_view);
      mul_v2_v2(co, center_scale_px);
      center_dist_sq_test = len_squared_v2(co);
      isect = center_dist_sq_test <= center_dist_sq_max;
      if (isect) {
        /* Use an active strip penalty for "center" selection when cycle is enabled. */
        if (use_cycle && (seq == seq_active) && (seq_active->flag & SELECT)) {
          center_dist_sq_test = square_f(sqrtf(center_dist_sq_test) + (3.0f * U.pixelsize));
        }
      }
    }
    else {
      isect = seq_point_image_isect(scene, seq, mouseco_view);
    }
 
    if (isect) {
      SeqSelect_Link *slink = MEM_cnew<SeqSelect_Link>(__func__);
      slink->seq = seq;
      slink->center_dist_sq = center_dist_sq_test;
      BLI_addtail(&strips_ordered, slink);
 
      if (seq == seq_active) {
        slink_active = slink;
      }
    }
  }
 
  BLI_listbase_sort(&strips_ordered,
                    center ? seq_sort_for_center_select : seq_sort_for_depth_select);
 
  SeqSelect_Link *slink_select = static_cast<SeqSelect_Link *>(strips_ordered.first);
  Sequence *seq_select = nullptr;
  if (slink_select != nullptr) {
    /* Only use special behavior for the active strip when it's selected. */
    if ((center == false) && slink_active && (seq_active->flag & SELECT)) {
      if (use_cycle) {
        if (slink_active->next) {
          slink_select = slink_active->next;
        }
      }
      else {
        /* Match object selection behavior: keep the current active item unless cycle is enabled.
         * Clicking again in the same location will cycle away from the active object. */
        slink_select = slink_active;
      }
    }
    seq_select = slink_select->seq;
  }
 
  BLI_freelistN(&strips_ordered);
 
  return seq_select;
}
 
bool ED_sequencer_handle_is_selected(const Sequence *seq, eSeqHandle handle)
{
  return ((handle == SEQ_HANDLE_LEFT) && (seq->flag & SEQ_LEFTSEL)) ||
         ((handle == SEQ_HANDLE_RIGHT) && (seq->flag & SEQ_RIGHTSEL));
}
 
static bool element_already_selected(const StripSelection &selection)
{
  if (selection.seq1 == nullptr) {
    return false;
  }
  const bool seq1_already_selected = ((selection.seq1->flag & SELECT) != 0);
  if (selection.seq2 == nullptr) {
    const bool handle_already_selected = ED_sequencer_handle_is_selected(selection.seq1,
                                                                         selection.handle) ||
                                         selection.handle == SEQ_HANDLE_NONE;
    return seq1_already_selected && handle_already_selected;
  }
  const bool seq2_already_selected = ((selection.seq2->flag & SELECT) != 0);
  const int seq1_handle = selection.seq1->flag & (SEQ_RIGHTSEL | SEQ_LEFTSEL);
  const int seq2_handle = selection.seq2->flag & (SEQ_RIGHTSEL | SEQ_LEFTSEL);
  /* Handles must be selected in XOR fashion, with `seq1` matching `handle_clicked`. */
  const bool both_handles_selected = seq1_handle == selection.handle && seq2_handle != 0 &&
                                     seq1_handle != seq2_handle;
  return seq1_already_selected && seq2_already_selected && both_handles_selected;
}
 
static void sequencer_select_connected_strips(const StripSelection &selection)
{
  blender::VectorSet<Sequence *> sources;
  sources.add(selection.seq1);
  if (selection.seq2) {
    sources.add(selection.seq2);
  }
 
  for (Sequence *source : sources) {
    blender::VectorSet<Sequence *> connections = SEQ_get_connected_strips(source);
    for (Sequence *connection : connections) {
      /* Copy selection settings exactly for connected strips. */
      connection->flag &= ~(SEQ_ALLSEL);
      connection->flag |= source->flag & (SEQ_ALLSEL);
    }
  }
}
 
static void sequencer_select_strip_impl(const Editing *ed,
                                        Sequence *seq,
                                        const eSeqHandle handle_clicked,
                                        const bool extend,
                                        const bool deselect,
                                        const bool toggle)
{
  const bool is_active = (ed->act_seq == seq);
 
  /* Exception for active strip handles. */
  if ((handle_clicked != SEQ_HANDLE_NONE) && (seq->flag & SELECT) && is_active && toggle) {
    if (handle_clicked == SEQ_HANDLE_LEFT) {
      seq->flag ^= SEQ_LEFTSEL;
    }
    else if (handle_clicked == SEQ_HANDLE_RIGHT) {
      seq->flag ^= SEQ_RIGHTSEL;
    }
    return;
  }
 
  /* Select strip. */
  /* Match object selection behavior. */
  int action = -1;
  if (extend) {
    action = 1;
  }
  else if (deselect) {
    action = 0;
  }
  else {
    if (!((seq->flag & SELECT) && is_active)) {
      action = 1;
    }
    else if (toggle) {
      action = 0;
    }
  }
 
  if (action == 1) {
    seq->flag |= SELECT;
    if (handle_clicked == SEQ_HANDLE_LEFT) {
      seq->flag |= SEQ_LEFTSEL;
    }
    if (handle_clicked == SEQ_HANDLE_RIGHT) {
      seq->flag |= SEQ_RIGHTSEL;
    }
  }
  else if (action == 0) {
    seq->flag &= ~SEQ_ALLSEL;
  }
}
 
static void select_linked_time(const Scene *scene,
                               const StripSelection &selection,
                               const bool extend,
                               const bool deselect,
                               const bool toggle)
{
  Editing *ed = SEQ_editing_get(scene);
 
  sequencer_select_strip_impl(ed, selection.seq1, selection.handle, extend, deselect, toggle);
  select_linked_time_seq(scene, selection.seq1, selection.handle);
 
  if (selection.seq2 != nullptr) {
    eSeqHandle seq2_handle_clicked = (selection.handle == SEQ_HANDLE_LEFT) ? SEQ_HANDLE_RIGHT :
                                                                             SEQ_HANDLE_LEFT;
    sequencer_select_strip_impl(ed, selection.seq2, seq2_handle_clicked, extend, deselect, toggle);
    select_linked_time_seq(scene, selection.seq2, seq2_handle_clicked);
  }
}
 
/* Similar to `sequence_handle_size_get_clamped()` but allows for larger clickable area. */
static float clickable_handle_size_get(const Scene *scene, const Sequence *seq, const View2D *v2d)
{
  const float pixelx = 1 / UI_view2d_scale_get_x(v2d);
  const float strip_len = SEQ_time_right_handle_frame_get(scene, seq) -
                          SEQ_time_left_handle_frame_get(scene, seq);
  return min_ff(15.0f * pixelx * U.pixelsize, strip_len / 4);
}
 
bool ED_sequencer_can_select_handle(const Scene *scene, const Sequence *seq, const View2D *v2d)
{
  if (SEQ_effect_get_num_inputs(seq->type) > 0) {
    return false;
  }
 
  Editing *ed = SEQ_editing_get(scene);
  ListBase *channels = SEQ_channels_displayed_get(ed);
  if (SEQ_transform_is_locked(channels, seq)) {
    return false;
  }
 
  int min_len = 25 * U.pixelsize;
  if ((U.sequencer_editor_flag & USER_SEQ_ED_SIMPLE_TWEAKING) == 0) {
    min_len = 15 * U.pixelsize;
  }
 
  const float pixelx = 1 / UI_view2d_scale_get_x(v2d);
  const int strip_len = SEQ_time_right_handle_frame_get(scene, seq) -
                        SEQ_time_left_handle_frame_get(scene, seq);
  if (strip_len / pixelx < min_len) {
    return false;
  }
  return true;
}
 
static void strip_clickable_areas_get(const Scene *scene,
                                      const Sequence *seq,
                                      const View2D *v2d,
                                      rctf *r_body,
                                      rctf *r_left_handle,
                                      rctf *r_right_handle)
{
  seq_rectf(scene, seq, r_body);
  *r_left_handle = *r_body;
  *r_right_handle = *r_body;
 
  const float handsize = clickable_handle_size_get(scene, seq, v2d);
  BLI_rctf_pad(r_left_handle, handsize / 3, 0.0f);
  BLI_rctf_pad(r_right_handle, handsize / 3, 0.0f);
  r_left_handle->xmax = r_body->xmin + handsize;
  r_right_handle->xmin = r_body->xmax - handsize;
  BLI_rctf_pad(r_body, -handsize, 0.0f);
}
 
static rctf strip_clickable_area_get(const Scene *scene, const View2D *v2d, const Sequence *seq)
{
  rctf body, left, right;
  strip_clickable_areas_get(scene, seq, v2d, &body, &left, &right);
  BLI_rctf_union(&body, &left);
  BLI_rctf_union(&body, &right);
  return body;
}
 
static float strip_to_frame_distance(const Scene *scene,
                                     const View2D *v2d,
                                     const Sequence *seq,
                                     float timeline_frame)
{
  rctf body, left, right;
  strip_clickable_areas_get(scene, seq, v2d, &body, &left, &right);
  return BLI_rctf_length_x(&body, timeline_frame);
}
 
/* Get strips that can be selected by click. */
static blender::Vector<Sequence *> mouseover_strips_sorted_get(const Scene *scene,
                                                               const View2D *v2d,
                                                               float mouse_co[2])
{
  Editing *ed = SEQ_editing_get(scene);
 
  blender::Vector<Sequence *> strips;
  LISTBASE_FOREACH (Sequence *, seq, ed->seqbasep) {
    if (seq->machine != int(mouse_co[1])) {
      continue;
    }
    if (SEQ_time_left_handle_frame_get(scene, seq) > v2d->cur.xmax) {
      continue;
    }
    if (SEQ_time_right_handle_frame_get(scene, seq) < v2d->cur.xmin) {
      continue;
    }
    const rctf body = strip_clickable_area_get(scene, v2d, seq);
    if (!BLI_rctf_isect_pt_v(&body, mouse_co)) {
      continue;
    }
    strips.append(seq);
  }
 
  BLI_assert(strips.size() <= 2);
 
  /* Ensure that `strips[0]` is the strip closest to the mouse cursor. */
  if (strips.size() == 2 && strip_to_frame_distance(scene, v2d, strips[0], mouse_co[0]) >
                                strip_to_frame_distance(scene, v2d, strips[1], mouse_co[0]))
  {
    std::swap(strips[0], strips[1]);
  }
 
  return strips;
}
 
static bool strips_are_adjacent(const Scene *scene, const Sequence *seq1, const Sequence *seq2)
{
  const int s1_left = SEQ_time_left_handle_frame_get(scene, seq1);
  const int s1_right = SEQ_time_right_handle_frame_get(scene, seq1);
  const int s2_left = SEQ_time_left_handle_frame_get(scene, seq2);
  const int s2_right = SEQ_time_right_handle_frame_get(scene, seq2);
 
  return s1_right == s2_left || s1_left == s2_right;
}
 
static eSeqHandle get_strip_handle_under_cursor(const Scene *scene,
                                                const Sequence *seq,
                                                const View2D *v2d,
                                                float mouse_co[2])
{
  if (!ED_sequencer_can_select_handle(scene, seq, v2d)) {
    return SEQ_HANDLE_NONE;
  }
 
  rctf body, left, right;
  strip_clickable_areas_get(scene, seq, v2d, &body, &left, &right);
  if (BLI_rctf_isect_pt_v(&left, mouse_co)) {
    return SEQ_HANDLE_LEFT;
  }
  if (BLI_rctf_isect_pt_v(&right, mouse_co)) {
    return SEQ_HANDLE_RIGHT;
  }
 
  return SEQ_HANDLE_NONE;
}
 
static bool is_mouse_over_both_handles_of_adjacent_strips(const Scene *scene,
                                                          blender::Vector<Sequence *> strips,
                                                          const View2D *v2d,
                                                          float mouse_co[2])
{
  const eSeqHandle seq1_handle = get_strip_handle_under_cursor(scene, strips[0], v2d, mouse_co);
 
  if (seq1_handle == SEQ_HANDLE_NONE) {
    return false;
  }
  if (!strips_are_adjacent(scene, strips[0], strips[1])) {
    return false;
  }
  const eSeqHandle seq2_handle = get_strip_handle_under_cursor(scene, strips[1], v2d, mouse_co);
  if (seq1_handle == SEQ_HANDLE_RIGHT && seq2_handle != SEQ_HANDLE_LEFT) {
    return false;
  }
  else if (seq1_handle == SEQ_HANDLE_LEFT && seq2_handle != SEQ_HANDLE_RIGHT) {
    return false;
  }
 
  return true;
}
 
StripSelection ED_sequencer_pick_strip_and_handle(const Scene *scene,
                                                  const View2D *v2d,
                                                  float mouse_co[2])
{
  blender::Vector<Sequence *> strips = mouseover_strips_sorted_get(scene, v2d, mouse_co);
 
  StripSelection selection;
 
  if (strips.size() == 0) {
    return selection;
  }
 
  selection.seq1 = strips[0];
  selection.handle = get_strip_handle_under_cursor(scene, selection.seq1, v2d, mouse_co);
 
  if (strips.size() == 2 && (U.sequencer_editor_flag & USER_SEQ_ED_SIMPLE_TWEAKING) != 0 &&
      is_mouse_over_both_handles_of_adjacent_strips(scene, strips, v2d, mouse_co))
  {
    selection.seq2 = strips[1];
  }
 
  return selection;
}
 
int sequencer_select_exec(bContext *C, wmOperator *op)
{
  const View2D *v2d = UI_view2d_fromcontext(C);
  Scene *scene = CTX_data_scene(C);
  Editing *ed = SEQ_editing_get(scene);
  ARegion *region = CTX_wm_region(C);
 
  if (ed == nullptr) {
    return OPERATOR_CANCELLED;
  }
 
  if (region->regiontype == RGN_TYPE_PREVIEW) {
    if (!sequencer_view_preview_only_poll(C)) {
      return OPERATOR_CANCELLED;
    }
    const SpaceSeq *sseq = CTX_wm_space_seq(C);
    if (sseq->mainb != SEQ_DRAW_IMG_IMBUF) {
      return OPERATOR_CANCELLED;
    }
  }
 
  bool was_retiming = sequencer_retiming_mode_is_active(C);
 
  MouseCoords mouse_co(v2d, RNA_int_get(op->ptr, "mouse_x"), RNA_int_get(op->ptr, "mouse_y"));
 
  /* Check to see if the mouse cursor intersects with the retiming box; if so, `seq_key_owner` is
   * set. If the cursor intersects with a retiming key, `key` will be set too. */
  Sequence *seq_key_owner = nullptr;
  SeqRetimingKey *key = retiming_mouseover_key_get(C, mouse_co.region, &seq_key_owner);
 
  /* If no key was found, the mouse cursor may still intersect with a "fake key" that has not been
   * realized yet. */
  if (seq_key_owner != nullptr && key == nullptr &&
      retiming_keys_can_be_displayed(CTX_wm_space_seq(C)) &&
      SEQ_retiming_data_is_editable(seq_key_owner))
  {
    key = try_to_realize_fake_keys(C, seq_key_owner, mouse_co.region);
  }
 
  if (key != nullptr) {
    if (!was_retiming) {
      ED_sequencer_deselect_all(scene);
    }
    /* Attempt to realize any other connected strips' fake keys. */
    if (SEQ_is_strip_connected(seq_key_owner)) {
      const int key_frame = SEQ_retiming_key_timeline_frame_get(scene, seq_key_owner, key);
      blender::VectorSet<Sequence *> connections = SEQ_get_connected_strips(seq_key_owner);
      for (Sequence *connection : connections) {
        if (key_frame == left_fake_key_frame_get(C, connection) ||
            key_frame == right_fake_key_frame_get(C, connection))
        {
          realize_fake_keys(scene, connection);
        }
      }
    }
    return sequencer_retiming_key_select_exec(C, op, key, seq_key_owner);
  }
 
  /* We should only reach here if no retiming selection is happening. */
  if (was_retiming) {
    SEQ_retiming_selection_clear(ed);
    WM_event_add_notifier(C, NC_SCENE | ND_SEQUENCER, scene);
  }
 
  bool extend = RNA_boolean_get(op->ptr, "extend");
  bool deselect = RNA_boolean_get(op->ptr, "deselect");
  bool deselect_all = RNA_boolean_get(op->ptr, "deselect_all");
  bool toggle = RNA_boolean_get(op->ptr, "toggle");
  bool center = RNA_boolean_get(op->ptr, "center");
 
  StripSelection selection;
  if (region->regiontype == RGN_TYPE_PREVIEW) {
    selection.seq1 = seq_select_seq_from_preview(C, mouse_co.region, toggle, extend, center);
  }
  else {
    selection = ED_sequencer_pick_strip_and_handle(scene, v2d, mouse_co.view);
  }
 
  /* NOTE: `side_of_frame` and `linked_time` functionality is designed to be shared on one
   * keymap, therefore both properties can be true at the same time. */
  if (selection.seq1 && RNA_boolean_get(op->ptr, "linked_time")) {
    if (!extend && !toggle) {
      ED_sequencer_deselect_all(scene);
    }
    select_linked_time(scene, selection, extend, deselect, toggle);
    sequencer_select_do_updates(C, scene);
    sequencer_select_set_active(scene, selection.seq1);
    return OPERATOR_FINISHED;
  }
 
  /* Select left, right or overlapping the current frame. */
  if (RNA_boolean_get(op->ptr, "side_of_frame")) {
    if (!extend && !toggle) {
      ED_sequencer_deselect_all(scene);
    }
    sequencer_select_side_of_frame(C, v2d, mouse_co.region, scene);
    sequencer_select_do_updates(C, scene);
    return OPERATOR_FINISHED;
  }
 
  /* On Alt selection, select the strip and bordering handles. */
  if (selection.seq1 && RNA_boolean_get(op->ptr, "linked_handle")) {
    if (!extend && !toggle) {
      ED_sequencer_deselect_all(scene);
    }
    sequencer_select_linked_handle(C, selection.seq1, selection.handle);
    sequencer_select_do_updates(C, scene);
    sequencer_select_set_active(scene, selection.seq1);
    return OPERATOR_FINISHED;
  }
 
  const bool wait_to_deselect_others = RNA_boolean_get(op->ptr, "wait_to_deselect_others");
  const bool already_selected = element_already_selected(selection);
 
  SpaceSeq *sseq = CTX_wm_space_seq(C);
  if (selection.handle != SEQ_HANDLE_NONE && already_selected) {
    sseq->flag &= ~SPACE_SEQ_DESELECT_STRIP_HANDLE;
  }
  else {
    sseq->flag |= SPACE_SEQ_DESELECT_STRIP_HANDLE;
  }
  const bool ignore_connections = RNA_boolean_get(op->ptr, "ignore_connections");
 
  /* Clicking on already selected element falls on modal operation.
   * All strips are deselected on mouse button release unless extend mode is used. */
  if (already_selected && wait_to_deselect_others && !toggle && !ignore_connections) {
    return OPERATOR_RUNNING_MODAL;
  }
 
  bool changed = false;
 
  /* Deselect everything */
  if (deselect_all ||
      (selection.seq1 && (extend == false && deselect == false && toggle == false)))
  {
    changed |= ED_sequencer_deselect_all(scene);
  }
 
  /* Nothing to select, but strips could be deselected. */
  if (!selection.seq1) {
    if (changed) {
      sequencer_select_do_updates(C, scene);
    }
    return changed ? OPERATOR_FINISHED : OPERATOR_CANCELLED;
  }
 
  /* Do actual selection. */
  sequencer_select_strip_impl(ed, selection.seq1, selection.handle, extend, deselect, toggle);
  if (selection.seq2 != nullptr) {
    /* Invert handle selection for second strip */
    eSeqHandle seq2_handle_clicked = (selection.handle == SEQ_HANDLE_LEFT) ? SEQ_HANDLE_RIGHT :
                                                                             SEQ_HANDLE_LEFT;
    sequencer_select_strip_impl(ed, selection.seq2, seq2_handle_clicked, extend, deselect, toggle);
  }
 
  if (!ignore_connections) {
    sequencer_select_connected_strips(selection);
  }
 
  sequencer_select_do_updates(C, scene);
  sequencer_select_set_active(scene, selection.seq1);
  return OPERATOR_FINISHED;
}
 
static int sequencer_select_invoke(bContext *C, wmOperator *op, const wmEvent *event)
{
  const int retval = WM_generic_select_invoke(C, op, event);
  ARegion *region = CTX_wm_region(C);
  if (region && (region->regiontype == RGN_TYPE_PREVIEW)) {
    return WM_operator_flag_only_pass_through_on_press(retval, event);
  }
  return retval;
}
 
void SEQUENCER_OT_select(wmOperatorType *ot)
{
  PropertyRNA *prop;
 
  /* Identifiers. */
  ot->name = "Select";
  ot->idname = "SEQUENCER_OT_select";
  ot->description = "Select a strip (last selected becomes the \"active strip\")";
 
  /* Api callbacks. */
  ot->exec = sequencer_select_exec;
  ot->invoke = sequencer_select_invoke;
  ot->modal = WM_generic_select_modal;
  ot->poll = ED_operator_sequencer_active;
  ot->get_name = ED_select_pick_get_name;
 
  /* Flags. */
  ot->flag = OPTYPE_UNDO;
 
  /* Properties. */
  WM_operator_properties_generic_select(ot);
 
  WM_operator_properties_mouse_select(ot);
 
  prop = RNA_def_boolean(
      ot->srna,
      "center",
      false,
      "Center",
      "Use the object center when selecting, in edit mode used to extend object selection");
  RNA_def_property_flag(prop, PROP_SKIP_SAVE);
 
  prop = RNA_def_boolean(ot->srna,
                         "linked_handle",
                         false,
                         "Linked Handle",
                         "Select handles next to the active strip");
  RNA_def_property_flag(prop, PROP_SKIP_SAVE);
 
  prop = RNA_def_boolean(ot->srna,
                         "linked_time",
                         false,
                         "Linked Time",
                         "Select other strips or handles at the same time, or all retiming keys "
                         "after the current in retiming mode");
  RNA_def_property_flag(prop, PROP_SKIP_SAVE);
 
  prop = RNA_def_boolean(
      ot->srna,
      "side_of_frame",
      false,
      "Side of Frame",
      "Select all strips on same side of the current frame as the mouse cursor");
  RNA_def_property_flag(prop, PROP_SKIP_SAVE);
 
  prop = RNA_def_boolean(ot->srna,
                         "ignore_connections",
                         false,
                         "Ignore Connections",
                         "Select strips individually whether or not they are connected");
  RNA_def_property_flag(prop, PROP_SKIP_SAVE);
}

 
/* -------------------------------------------------------------------- */
 
static int sequencer_select_handle_exec(bContext *C, wmOperator *op)
{
  const View2D *v2d = UI_view2d_fromcontext(C);
  Scene *scene = CTX_data_scene(C);
  Editing *ed = SEQ_editing_get(scene);
 
  if (ed == nullptr) {
    return OPERATOR_CANCELLED;
  }
 
  if ((U.sequencer_editor_flag & USER_SEQ_ED_SIMPLE_TWEAKING) == 0) {
    return OPERATOR_CANCELLED | OPERATOR_PASS_THROUGH;
  }
 
  MouseCoords mouse_co(v2d, RNA_int_get(op->ptr, "mouse_x"), RNA_int_get(op->ptr, "mouse_y"));
 
  StripSelection selection = ED_sequencer_pick_strip_and_handle(scene, v2d, mouse_co.view);
  if (selection.seq1 == nullptr || selection.handle == SEQ_HANDLE_NONE) {
    return OPERATOR_CANCELLED | OPERATOR_PASS_THROUGH;
  }
 
  /* Ignore clicks on retiming keys. */
  Sequence *seq_key_test = nullptr;
  SeqRetimingKey *key = retiming_mouseover_key_get(C, mouse_co.region, &seq_key_test);
  if (key != nullptr) {
    return OPERATOR_CANCELLED | OPERATOR_PASS_THROUGH;
  }
 
  SpaceSeq *sseq = CTX_wm_space_seq(C);
  if (element_already_selected(selection)) {
    sseq->flag &= ~SPACE_SEQ_DESELECT_STRIP_HANDLE;
    return OPERATOR_CANCELLED | OPERATOR_PASS_THROUGH;
  }
  else {
    sseq->flag |= SPACE_SEQ_DESELECT_STRIP_HANDLE;
    ED_sequencer_deselect_all(scene);
  }
 
  /* Do actual selection. */
  sequencer_select_strip_impl(ed, selection.seq1, selection.handle, false, false, false);
  if (selection.seq2 != nullptr) {
    /* Invert handle selection for second strip */
    eSeqHandle seq2_handle_clicked = (selection.handle == SEQ_HANDLE_LEFT) ? SEQ_HANDLE_RIGHT :
                                                                             SEQ_HANDLE_LEFT;
    sequencer_select_strip_impl(ed, selection.seq2, seq2_handle_clicked, false, false, false);
  }
 
  const bool ignore_connections = RNA_boolean_get(op->ptr, "ignore_connections");
  if (!ignore_connections) {
    sequencer_select_connected_strips(selection);
  }
 
  SEQ_retiming_selection_clear(ed);
  sequencer_select_do_updates(C, scene);
  sequencer_select_set_active(scene, selection.seq1);
  return OPERATOR_FINISHED | OPERATOR_PASS_THROUGH;
}
 
static int sequencer_select_handle_invoke(bContext *C, wmOperator *op, const wmEvent *event)
{
  ARegion *region = CTX_wm_region(C);
 
  int mval[2];
  WM_event_drag_start_mval(event, region, mval);
 
  RNA_int_set(op->ptr, "mouse_x", mval[0]);
  RNA_int_set(op->ptr, "mouse_y", mval[1]);
 
  return sequencer_select_handle_exec(C, op);
}
 
void SEQUENCER_OT_select_handle(wmOperatorType *ot)
{
  PropertyRNA *prop;
 
  /* Identifiers. */
  ot->name = "Select Handle";
  ot->idname = "SEQUENCER_OT_select_handle";
  ot->description = "Select strip handle";
 
  /* Api callbacks. */
  ot->exec = sequencer_select_handle_exec;
  ot->invoke = sequencer_select_handle_invoke;
  ot->poll = ED_operator_sequencer_active;
 
  /* Flags. */
  ot->flag = OPTYPE_UNDO;
 
  /* Properties. */
  WM_operator_properties_generic_select(ot);
 
  prop = RNA_def_boolean(ot->srna,
                         "ignore_connections",
                         false,
                         "Ignore Connections",
                         "Select strips individually whether or not they are connected");
  RNA_def_property_flag(prop, PROP_SKIP_SAVE);
}

 
/* -------------------------------------------------------------------- */
 
/* Run recursively to select linked. */
static bool select_linked_internal(Scene *scene)
{
  Editing *ed = SEQ_editing_get(scene);
 
  if (ed == nullptr) {
    return false;
  }
 
  bool changed = false;
 
  LISTBASE_FOREACH (Sequence *, seq, SEQ_active_seqbase_get(ed)) {
    if ((seq->flag & SELECT) == 0) {
      continue;
    }
    /* Only get unselected neighbors. */
    Sequence *neighbor = find_neighboring_sequence(scene, seq, SEQ_SIDE_LEFT, 0);
    if (neighbor) {
      neighbor->flag |= SELECT;
      recurs_sel_seq(neighbor);
      changed = true;
    }
    neighbor = find_neighboring_sequence(scene, seq, SEQ_SIDE_RIGHT, 0);
    if (neighbor) {
      neighbor->flag |= SELECT;
      recurs_sel_seq(neighbor);
      changed = true;
    }
  }
 
  return changed;
}
 
/* Select only one linked strip on each side. */
static bool select_more_less_seq__internal(Scene *scene, bool select_more)
{
  Editing *ed = SEQ_editing_get(scene);
 
  if (ed == nullptr) {
    return false;
  }
 
  GSet *neighbors = BLI_gset_new(BLI_ghashutil_ptrhash, BLI_ghashutil_ptrcmp, "Linked strips");
  const int neighbor_selection_filter = select_more ? 0 : SELECT;
  const int selection_filter = select_more ? SELECT : 0;
 
  LISTBASE_FOREACH (Sequence *, seq, SEQ_active_seqbase_get(ed)) {
    if ((seq->flag & SELECT) != selection_filter) {
      continue;
    }
    Sequence *neighbor = find_neighboring_sequence(
        scene, seq, SEQ_SIDE_LEFT, neighbor_selection_filter);
    if (neighbor) {
      BLI_gset_add(neighbors, neighbor);
    }
    neighbor = find_neighboring_sequence(scene, seq, SEQ_SIDE_RIGHT, neighbor_selection_filter);
    if (neighbor) {
      BLI_gset_add(neighbors, neighbor);
    }
  }
 
  bool changed = false;
  GSetIterator gsi;
  BLI_gsetIterator_init(&gsi, neighbors);
  while (!BLI_gsetIterator_done(&gsi)) {
    Sequence *neighbor = static_cast<Sequence *>(BLI_gsetIterator_getKey(&gsi));
    if (select_more) {
      neighbor->flag |= SELECT;
      recurs_sel_seq(neighbor);
    }
    else {
      neighbor->flag &= ~SELECT;
    }
    changed = true;
    BLI_gsetIterator_step(&gsi);
  }
 
  BLI_gset_free(neighbors, nullptr);
  return changed;
}
 
static int sequencer_select_more_exec(bContext *C, wmOperator * /*op*/)
{
  Scene *scene = CTX_data_scene(C);
 
  if (!select_more_less_seq__internal(scene, true)) {
    return OPERATOR_CANCELLED;
  }
 
  ED_outliner_select_sync_from_sequence_tag(C);
 
  WM_event_add_notifier(C, NC_SCENE | ND_SEQUENCER | NA_SELECTED, scene);
 
  return OPERATOR_FINISHED;
}
 
void SEQUENCER_OT_select_more(wmOperatorType *ot)
{
  /* Identifiers. */
  ot->name = "Select More";
  ot->idname = "SEQUENCER_OT_select_more";
  ot->description = "Select more strips adjacent to the current selection";
 
  /* Api callbacks. */
  ot->exec = sequencer_select_more_exec;
  ot->poll = sequencer_edit_poll;
 
  /* Flags. */
  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
}

 
/* -------------------------------------------------------------------- */
 
static int sequencer_select_less_exec(bContext *C, wmOperator * /*op*/)
{
  Scene *scene = CTX_data_scene(C);
 
  if (!select_more_less_seq__internal(scene, false)) {
    return OPERATOR_CANCELLED;
  }
 
  ED_outliner_select_sync_from_sequence_tag(C);
 
  WM_event_add_notifier(C, NC_SCENE | ND_SEQUENCER | NA_SELECTED, scene);
 
  return OPERATOR_FINISHED;
}
 
void SEQUENCER_OT_select_less(wmOperatorType *ot)
{
  /* Identifiers. */
  ot->name = "Select Less";
  ot->idname = "SEQUENCER_OT_select_less";
  ot->description = "Shrink the current selection of adjacent selected strips";
 
  /* Api callbacks. */
  ot->exec = sequencer_select_less_exec;
  ot->poll = sequencer_edit_poll;
 
  /* Flags. */
  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
}

 
/* -------------------------------------------------------------------- */
 
static int sequencer_select_linked_pick_invoke(bContext *C, wmOperator *op, const wmEvent *event)
{
  Scene *scene = CTX_data_scene(C);
  View2D *v2d = UI_view2d_fromcontext(C);
 
  bool extend = RNA_boolean_get(op->ptr, "extend");
 
  Sequence *mouse_seq;
  eSeqHandle hand;
  int selected;
 
  /* This works like UV, not mesh. */
  mouse_seq = find_nearest_seq(scene, v2d, event->mval, &hand);
  if (!mouse_seq) {
    return OPERATOR_FINISHED; /* User error as with mesh?? */
  }
 
  if (extend == 0) {
    ED_sequencer_deselect_all(scene);
  }
 
  mouse_seq->flag |= SELECT;
  recurs_sel_seq(mouse_seq);
 
  selected = 1;
  while (selected) {
    selected = select_linked_internal(scene);
  }
 
  ED_outliner_select_sync_from_sequence_tag(C);
 
  WM_event_add_notifier(C, NC_SCENE | ND_SEQUENCER | NA_SELECTED, scene);
 
  return OPERATOR_FINISHED;
}
 
void SEQUENCER_OT_select_linked_pick(wmOperatorType *ot)
{
  /* Identifiers. */
  ot->name = "Select Pick Linked";
  ot->idname = "SEQUENCER_OT_select_linked_pick";
  ot->description = "Select a chain of linked strips nearest to the mouse pointer";
 
  /* Api callbacks. */
  ot->invoke = sequencer_select_linked_pick_invoke;
  ot->poll = ED_operator_sequencer_active;
 
  /* Flags. */
  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 
  /* Properties. */
  PropertyRNA *prop;
  prop = RNA_def_boolean(ot->srna, "extend", false, "Extend", "Extend the selection");
  RNA_def_property_flag(prop, PROP_SKIP_SAVE);
}

 
/* -------------------------------------------------------------------- */
 
static int sequencer_select_linked_exec(bContext *C, wmOperator * /*op*/)
{
  Scene *scene = CTX_data_scene(C);
  bool selected;
 
  selected = true;
  while (selected) {
    selected = select_linked_internal(scene);
  }
 
  ED_outliner_select_sync_from_sequence_tag(C);
 
  WM_event_add_notifier(C, NC_SCENE | ND_SEQUENCER | NA_SELECTED, scene);
 
  return OPERATOR_FINISHED;
}
 
void SEQUENCER_OT_select_linked(wmOperatorType *ot)
{
  /* Identifiers. */
  ot->name = "Select Linked";
  ot->idname = "SEQUENCER_OT_select_linked";
  ot->description = "Select all strips adjacent to the current selection";
 
  /* Api callbacks. */
  ot->exec = sequencer_select_linked_exec;
  ot->poll = sequencer_edit_poll;
 
  /* Flags. */
  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
}

 
/* -------------------------------------------------------------------- */
 
enum {
  SEQ_SELECT_HANDLES_SIDE_LEFT,
  SEQ_SELECT_HANDLES_SIDE_RIGHT,
  SEQ_SELECT_HANDLES_SIDE_BOTH,
  SEQ_SELECT_HANDLES_SIDE_LEFT_NEIGHBOR,
  SEQ_SELECT_HANDLES_SIDE_RIGHT_NEIGHBOR,
  SEQ_SELECT_HANDLES_SIDE_BOTH_NEIGHBORS,
};
 
static const EnumPropertyItem prop_select_handles_side_types[] = {
    {SEQ_SELECT_HANDLES_SIDE_LEFT, "LEFT", 0, "Left", ""},
    {SEQ_SELECT_HANDLES_SIDE_RIGHT, "RIGHT", 0, "Right", ""},
    {SEQ_SELECT_HANDLES_SIDE_BOTH, "BOTH", 0, "Both", ""},
    {SEQ_SELECT_HANDLES_SIDE_LEFT_NEIGHBOR, "LEFT_NEIGHBOR", 0, "Left Neighbor", ""},
    {SEQ_SELECT_HANDLES_SIDE_RIGHT_NEIGHBOR, "RIGHT_NEIGHBOR", 0, "Right Neighbor", ""},
    {SEQ_SELECT_HANDLES_SIDE_BOTH_NEIGHBORS, "BOTH_NEIGHBORS", 0, "Both Neighbors", ""},
    {0, nullptr, 0, nullptr, nullptr},
};
 
static int sequencer_select_handles_exec(bContext *C, wmOperator *op)
{
  Scene *scene = CTX_data_scene(C);
  Editing *ed = SEQ_editing_get(scene);
  int sel_side = RNA_enum_get(op->ptr, "side");
  LISTBASE_FOREACH (Sequence *, seq, ed->seqbasep) {
    if (seq->flag & SELECT) {
      Sequence *l_neighbor = find_neighboring_sequence(scene, seq, SEQ_SIDE_LEFT, -1);
      Sequence *r_neighbor = find_neighboring_sequence(scene, seq, SEQ_SIDE_RIGHT, -1);
 
      switch (sel_side) {
        case SEQ_SELECT_HANDLES_SIDE_LEFT:
          seq->flag &= ~SEQ_RIGHTSEL;
          seq->flag |= SEQ_LEFTSEL;
          break;
        case SEQ_SELECT_HANDLES_SIDE_RIGHT:
          seq->flag &= ~SEQ_LEFTSEL;
          seq->flag |= SEQ_RIGHTSEL;
          break;
        case SEQ_SELECT_HANDLES_SIDE_BOTH:
          seq->flag |= SEQ_LEFTSEL | SEQ_RIGHTSEL;
          break;
        case SEQ_SELECT_HANDLES_SIDE_LEFT_NEIGHBOR:
          if (l_neighbor) {
            if (!(l_neighbor->flag & SELECT)) {
              l_neighbor->flag |= SEQ_RIGHTSEL;
            }
          }
          break;
        case SEQ_SELECT_HANDLES_SIDE_RIGHT_NEIGHBOR:
          if (r_neighbor) {
            if (!(r_neighbor->flag & SELECT)) {
              r_neighbor->flag |= SEQ_LEFTSEL;
            }
          }
          break;
        case SEQ_SELECT_HANDLES_SIDE_BOTH_NEIGHBORS:
          if (l_neighbor) {
            if (!(l_neighbor->flag & SELECT)) {
              l_neighbor->flag |= SEQ_RIGHTSEL;
            }
          }
          if (r_neighbor) {
            if (!(r_neighbor->flag & SELECT)) {
              r_neighbor->flag |= SEQ_LEFTSEL;
            }
            break;
          }
      }
    }
  }
  /*   Select strips */
  LISTBASE_FOREACH (Sequence *, seq, ed->seqbasep) {
    if ((seq->flag & SEQ_LEFTSEL) || (seq->flag & SEQ_RIGHTSEL)) {
      if (!(seq->flag & SELECT)) {
        seq->flag |= SELECT;
        recurs_sel_seq(seq);
      }
    }
  }
 
  ED_outliner_select_sync_from_sequence_tag(C);
 
  WM_event_add_notifier(C, NC_SCENE | ND_SEQUENCER | NA_SELECTED, scene);
 
  return OPERATOR_FINISHED;
}
 
void SEQUENCER_OT_select_handles(wmOperatorType *ot)
{
  /* Identifiers. */
  ot->name = "Select Handles";
  ot->idname = "SEQUENCER_OT_select_handles";
  ot->description = "Select gizmo handles on the sides of the selected strip";
 
  /* Api callbacks. */
  ot->exec = sequencer_select_handles_exec;
  ot->poll = sequencer_edit_poll;
 
  /* Flags. */
  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 
  /* Properties. */
  RNA_def_enum(ot->srna,
               "side",
               prop_select_handles_side_types,
               SEQ_SELECT_HANDLES_SIDE_BOTH,
               "Side",
               "The side of the handle that is selected");
}

 
/* -------------------------------------------------------------------- */
 
static int sequencer_select_side_of_frame_exec(bContext *C, wmOperator *op)
{
  Scene *scene = CTX_data_scene(C);
  Editing *ed = SEQ_editing_get(scene);
  const bool extend = RNA_boolean_get(op->ptr, "extend");
  const int side = RNA_enum_get(op->ptr, "side");
 
  if (ed == nullptr) {
    return OPERATOR_CANCELLED;
  }
  if (extend == false) {
    ED_sequencer_deselect_all(scene);
  }
  const int timeline_frame = scene->r.cfra;
  LISTBASE_FOREACH (Sequence *, seq, SEQ_active_seqbase_get(ed)) {
    bool test = false;
    switch (side) {
      case -1:
        test = (timeline_frame >= SEQ_time_right_handle_frame_get(scene, seq));
        break;
      case 1:
        test = (timeline_frame <= SEQ_time_left_handle_frame_get(scene, seq));
        break;
      case 2:
        test = SEQ_time_strip_intersects_frame(scene, seq, timeline_frame);
        break;
    }
 
    if (test) {
      seq->flag |= SELECT;
      recurs_sel_seq(seq);
    }
  }
 
  ED_outliner_select_sync_from_sequence_tag(C);
 
  WM_event_add_notifier(C, NC_SCENE | ND_SEQUENCER | NA_SELECTED, scene);
 
  return OPERATOR_FINISHED;
}
 
void SEQUENCER_OT_select_side_of_frame(wmOperatorType *ot)
{
  static const EnumPropertyItem sequencer_select_left_right_types[] = {
      {-1, "LEFT", 0, "Left", "Select to the left of the current frame"},
      {1, "RIGHT", 0, "Right", "Select to the right of the current frame"},
      {2, "CURRENT", 0, "Current Frame", "Select intersecting with the current frame"},
      {0, nullptr, 0, nullptr, nullptr},
  };
 
  /* Identifiers. */
  ot->name = "Select Side of Frame";
  ot->idname = "SEQUENCER_OT_select_side_of_frame";
  ot->description = "Select strips relative to the current frame";
 
  /* Api callbacks. */
  ot->exec = sequencer_select_side_of_frame_exec;
  ot->poll = ED_operator_sequencer_active;
 
  /* Flags. */
  ot->flag = OPTYPE_UNDO;
 
  /* Properties. */
  PropertyRNA *prop;
  prop = RNA_def_boolean(ot->srna, "extend", false, "Extend", "Extend the selection");
  RNA_def_property_flag(prop, PROP_SKIP_SAVE);
  ot->prop = RNA_def_enum(ot->srna, "side", sequencer_select_left_right_types, 0, "Side", "");
}

 
/* -------------------------------------------------------------------- */
 
static int sequencer_select_side_exec(bContext *C, wmOperator *op)
{
  Scene *scene = CTX_data_scene(C);
  Editing *ed = SEQ_editing_get(scene);
 
  const int sel_side = RNA_enum_get(op->ptr, "side");
  const int frame_init = sel_side == SEQ_SIDE_LEFT ? INT_MIN : INT_MAX;
  int frame_ranges[SEQ_MAX_CHANNELS];
  bool selected = false;
 
  copy_vn_i(frame_ranges, ARRAY_SIZE(frame_ranges), frame_init);
 
  LISTBASE_FOREACH (Sequence *, seq, ed->seqbasep) {
    if (UNLIKELY(seq->machine >= SEQ_MAX_CHANNELS)) {
      continue;
    }
    int *frame_limit_p = &frame_ranges[seq->machine];
    if (seq->flag & SELECT) {
      selected = true;
      if (sel_side == SEQ_SIDE_LEFT) {
        *frame_limit_p = max_ii(*frame_limit_p, SEQ_time_left_handle_frame_get(scene, seq));
      }
      else {
        *frame_limit_p = min_ii(*frame_limit_p, SEQ_time_left_handle_frame_get(scene, seq));
      }
    }
  }
 
  if (selected == false) {
    return OPERATOR_CANCELLED;
  }
 
  select_active_side_range(scene, ed->seqbasep, sel_side, frame_ranges, frame_init);
 
  ED_outliner_select_sync_from_sequence_tag(C);
 
  WM_event_add_notifier(C, NC_SCENE | ND_SEQUENCER | NA_SELECTED, scene);
 
  return OPERATOR_FINISHED;
}
 
void SEQUENCER_OT_select_side(wmOperatorType *ot)
{
  /* Identifiers. */
  ot->name = "Select Side";
  ot->idname = "SEQUENCER_OT_select_side";
  ot->description = "Select strips on the nominated side of the selected strips";
 
  /* Api callbacks. */
  ot->exec = sequencer_select_side_exec;
  ot->poll = sequencer_edit_poll;
 
  /* Flags. */
  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 
  /* Properties. */
  RNA_def_enum(ot->srna,
               "side",
               prop_side_types,
               SEQ_SIDE_BOTH,
               "Side",
               "The side to which the selection is applied");
}

 
/* -------------------------------------------------------------------- */
 
static bool seq_box_select_rect_image_isect(const Scene *scene,
                                            const Sequence *seq,
                                            const rctf *rect)
{
  float seq_image_quad[4][2];
  SEQ_image_transform_final_quad_get(scene, seq, seq_image_quad);
  float rect_quad[4][2] = {{rect->xmax, rect->ymax},
                           {rect->xmax, rect->ymin},
                           {rect->xmin, rect->ymin},
                           {rect->xmin, rect->ymax}};
 
  return seq_point_image_isect(scene, seq, rect_quad[0]) ||
         seq_point_image_isect(scene, seq, rect_quad[1]) ||
         seq_point_image_isect(scene, seq, rect_quad[2]) ||
         seq_point_image_isect(scene, seq, rect_quad[3]) ||
         isect_point_quad_v2(
             seq_image_quad[0], rect_quad[0], rect_quad[1], rect_quad[2], rect_quad[3]) ||
         isect_point_quad_v2(
             seq_image_quad[1], rect_quad[0], rect_quad[1], rect_quad[2], rect_quad[3]) ||
         isect_point_quad_v2(
             seq_image_quad[2], rect_quad[0], rect_quad[1], rect_quad[2], rect_quad[3]) ||
         isect_point_quad_v2(
             seq_image_quad[3], rect_quad[0], rect_quad[1], rect_quad[2], rect_quad[3]);
}
 
static void seq_box_select_seq_from_preview(const bContext *C,
                                            const rctf *rect,
                                            const eSelectOp mode)
{
  Scene *scene = CTX_data_scene(C);
  Editing *ed = SEQ_editing_get(scene);
  ListBase *seqbase = SEQ_active_seqbase_get(ed);
  ListBase *channels = SEQ_channels_displayed_get(ed);
  SpaceSeq *sseq = CTX_wm_space_seq(C);
 
  blender::VectorSet strips = SEQ_query_rendered_strips(
      scene, channels, seqbase, scene->r.cfra, sseq->chanshown);
  for (Sequence *seq : strips) {
    if (!seq_box_select_rect_image_isect(scene, seq, rect)) {
      continue;
    }
 
    if (ELEM(mode, SEL_OP_ADD, SEL_OP_SET)) {
      seq->flag |= SELECT;
    }
    else {
      BLI_assert(mode == SEL_OP_SUB);
      seq->flag &= ~SELECT;
    }
  }
}
 
static int sequencer_box_select_exec(bContext *C, wmOperator *op)
{
  Scene *scene = CTX_data_scene(C);
  View2D *v2d = UI_view2d_fromcontext(C);
  Editing *ed = SEQ_editing_get(scene);
 
  if (ed == nullptr) {
    return OPERATOR_CANCELLED;
  }
 
  if (sequencer_retiming_mode_is_active(C) && retiming_keys_can_be_displayed(CTX_wm_space_seq(C)))
  {
    return sequencer_retiming_box_select_exec(C, op);
  }
 
  const eSelectOp sel_op = eSelectOp(RNA_enum_get(op->ptr, "mode"));
  const bool handles = RNA_boolean_get(op->ptr, "include_handles");
  const bool select = (sel_op != SEL_OP_SUB);
 
  bool changed = false;
 
  if (SEL_OP_USE_PRE_DESELECT(sel_op)) {
    changed |= ED_sequencer_deselect_all(scene);
  }
 
  rctf rectf;
  WM_operator_properties_border_to_rctf(op, &rectf);
  UI_view2d_region_to_view_rctf(v2d, &rectf, &rectf);
 
  ARegion *region = CTX_wm_region(C);
  if (region->regiontype == RGN_TYPE_PREVIEW) {
    if (!sequencer_view_preview_only_poll(C)) {
      return OPERATOR_CANCELLED;
    }
    seq_box_select_seq_from_preview(C, &rectf, sel_op);
    sequencer_select_do_updates(C, scene);
    return OPERATOR_FINISHED;
  }
 
  LISTBASE_FOREACH (Sequence *, seq, ed->seqbasep) {
    rctf rq;
    seq_rectf(scene, seq, &rq);
    if (BLI_rctf_isect(&rq, &rectf, nullptr)) {
      if (handles) {
        /* Get the handles draw size. */
        float pixelx = BLI_rctf_size_x(&v2d->cur) / BLI_rcti_size_x(&v2d->mask);
        float handsize = sequence_handle_size_get_clamped(scene, seq, pixelx) * 4;
 
        /* Right handle. */
        if (rectf.xmax > (SEQ_time_right_handle_frame_get(scene, seq) - handsize)) {
          if (select) {
            seq->flag |= SELECT | SEQ_RIGHTSEL;
          }
          else {
            /* Deselect the strip if it's left with no handles selected. */
            if ((seq->flag & SEQ_RIGHTSEL) && ((seq->flag & SEQ_LEFTSEL) == 0)) {
              seq->flag &= ~SELECT;
            }
            seq->flag &= ~SEQ_RIGHTSEL;
          }
 
          changed = true;
        }
        /* Left handle. */
        if (rectf.xmin < (SEQ_time_left_handle_frame_get(scene, seq) + handsize)) {
          if (select) {
            seq->flag |= SELECT | SEQ_LEFTSEL;
          }
          else {
            /* Deselect the strip if it's left with no handles selected. */
            if ((seq->flag & SEQ_LEFTSEL) && ((seq->flag & SEQ_RIGHTSEL) == 0)) {
              seq->flag &= ~SELECT;
            }
            seq->flag &= ~SEQ_LEFTSEL;
          }
        }
 
        changed = true;
      }
 
      /* Regular box selection. */
      else {
        SET_FLAG_FROM_TEST(seq->flag, select, SELECT);
        seq->flag &= ~(SEQ_LEFTSEL | SEQ_RIGHTSEL);
        changed = true;
      }
 
      const bool ignore_connections = RNA_boolean_get(op->ptr, "ignore_connections");
      if (!ignore_connections) {
        /* Propagate selection to connected strips. */
        StripSelection selection;
        selection.seq1 = seq;
        sequencer_select_connected_strips(selection);
      }
    }
  }
 
  if (!changed) {
    return OPERATOR_CANCELLED;
  }
 
  sequencer_select_do_updates(C, scene);
 
  return OPERATOR_FINISHED;
}
 
static int sequencer_box_select_invoke(bContext *C, wmOperator *op, const wmEvent *event)
{
  Scene *scene = CTX_data_scene(C);
  const View2D *v2d = UI_view2d_fromcontext(C);
  ARegion *region = CTX_wm_region(C);
 
  if (region->regiontype == RGN_TYPE_PREVIEW && !sequencer_view_preview_only_poll(C)) {
    return OPERATOR_CANCELLED;
  }
 
  const bool tweak = RNA_boolean_get(op->ptr, "tweak");
 
  if (tweak) {
    int mval[2];
    float mouse_co[2];
    WM_event_drag_start_mval(event, region, mval);
    UI_view2d_region_to_view(v2d, mval[0], mval[1], &mouse_co[0], &mouse_co[1]);
 
    StripSelection selection = ED_sequencer_pick_strip_and_handle(scene, v2d, mouse_co);
 
    if (selection.seq1 != nullptr) {
      return OPERATOR_CANCELLED | OPERATOR_PASS_THROUGH;
    }
  }
 
  return WM_gesture_box_invoke(C, op, event);
}
 
void SEQUENCER_OT_select_box(wmOperatorType *ot)
{
  PropertyRNA *prop;
 
  /* Identifiers. */
  ot->name = "Box Select";
  ot->idname = "SEQUENCER_OT_select_box";
  ot->description = "Select strips using box selection";
 
  /* Api callbacks. */
  ot->invoke = sequencer_box_select_invoke;
  ot->exec = sequencer_box_select_exec;
  ot->modal = WM_gesture_box_modal;
  ot->cancel = WM_gesture_box_cancel;
 
  ot->poll = ED_operator_sequencer_active;
 
  /* Flags. */
  ot->flag = OPTYPE_UNDO;
 
  /* Properties. */
  WM_operator_properties_gesture_box(ot);
  WM_operator_properties_select_operation_simple(ot);
 
  prop = RNA_def_boolean(
      ot->srna,
      "tweak",
      false,
      "Tweak",
      "Make box select pass through to sequence slide when the cursor is hovering on a strip");
  RNA_def_property_flag(prop, PROP_SKIP_SAVE);
 
  prop = RNA_def_boolean(
      ot->srna, "include_handles", false, "Select Handles", "Select the strips and their handles");
  RNA_def_property_flag(prop, PROP_SKIP_SAVE);
 
  prop = RNA_def_boolean(ot->srna,
                         "ignore_connections",
                         false,
                         "Ignore Connections",
                         "Select strips individually whether or not they are connected");
  RNA_def_property_flag(prop, PROP_SKIP_SAVE);
}

 
/* -------------------------------------------------------------------- */
 
enum {
  SEQ_SELECT_GROUP_TYPE,
  SEQ_SELECT_GROUP_TYPE_BASIC,
  SEQ_SELECT_GROUP_TYPE_EFFECT,
  SEQ_SELECT_GROUP_DATA,
  SEQ_SELECT_GROUP_EFFECT,
  SEQ_SELECT_GROUP_EFFECT_LINK,
  SEQ_SELECT_GROUP_OVERLAP,
};
 
static const EnumPropertyItem sequencer_prop_select_grouped_types[] = {
    {SEQ_SELECT_GROUP_TYPE, "TYPE", 0, "Type", "Shared strip type"},
    {SEQ_SELECT_GROUP_TYPE_BASIC,
     "TYPE_BASIC",
     0,
     "Global Type",
     "All strips of same basic type (graphical or sound)"},
    {SEQ_SELECT_GROUP_TYPE_EFFECT,
     "TYPE_EFFECT",
     0,
     "Effect Type",
     "Shared strip effect type (if active strip is not an effect one, select all non-effect "
     "strips)"},
    {SEQ_SELECT_GROUP_DATA, "DATA", 0, "Data", "Shared data (scene, image, sound, etc.)"},
    {SEQ_SELECT_GROUP_EFFECT, "EFFECT", 0, "Effect", "Shared effects"},
    {SEQ_SELECT_GROUP_EFFECT_LINK,
     "EFFECT_LINK",
     0,
     "Effect/Linked",
     "Other strips affected by the active one (sharing some time, and below or "
     "effect-assigned)"},
    {SEQ_SELECT_GROUP_OVERLAP, "OVERLAP", 0, "Overlap", "Overlapping time"},
    {0, nullptr, 0, nullptr, nullptr},
};
 
#define SEQ_IS_SOUND(_seq) ((_seq->type & SEQ_TYPE_SOUND_RAM) && !(_seq->type & SEQ_TYPE_EFFECT))
 
#define SEQ_IS_EFFECT(_seq) ((_seq->type & SEQ_TYPE_EFFECT) != 0)
 
#define SEQ_USE_DATA(_seq) \
  (ELEM(_seq->type, SEQ_TYPE_SCENE, SEQ_TYPE_MOVIECLIP, SEQ_TYPE_MASK) || SEQ_HAS_PATH(_seq))
 
#define SEQ_CHANNEL_CHECK(_seq, _chan) ELEM((_chan), 0, (_seq)->machine)
 
static bool select_grouped_type(blender::Span<Sequence *> strips,
                                ListBase * /*seqbase*/,
                                Sequence *actseq,
                                const int channel)
{
  bool changed = false;
 
  for (Sequence *seq : strips) {
    if (SEQ_CHANNEL_CHECK(seq, channel) && seq->type == actseq->type) {
      seq->flag |= SELECT;
      changed = true;
    }
  }
 
  return changed;
}
 
static bool select_grouped_type_basic(blender::Span<Sequence *> strips,
                                      ListBase * /*seqbase*/,
                                      Sequence *actseq,
                                      const int channel)
{
  bool changed = false;
  const bool is_sound = SEQ_IS_SOUND(actseq);
 
  for (Sequence *seq : strips) {
    if (SEQ_CHANNEL_CHECK(seq, channel) && (is_sound ? SEQ_IS_SOUND(seq) : !SEQ_IS_SOUND(seq))) {
      seq->flag |= SELECT;
      changed = true;
    }
  }
 
  return changed;
}
 
static bool select_grouped_type_effect(blender::Span<Sequence *> strips,
                                       ListBase * /*seqbase*/,
                                       Sequence *actseq,
                                       const int channel)
{
  bool changed = false;
  const bool is_effect = SEQ_IS_EFFECT(actseq);
 
  for (Sequence *seq : strips) {
    if (SEQ_CHANNEL_CHECK(seq, channel) && (is_effect ? SEQ_IS_EFFECT(seq) : !SEQ_IS_EFFECT(seq)))
    {
      seq->flag |= SELECT;
      changed = true;
    }
  }
 
  return changed;
}
 
static bool select_grouped_data(blender::Span<Sequence *> strips,
                                ListBase * /*seqbase*/,
                                Sequence *actseq,
                                const int channel)
{
  bool changed = false;
  const char *dirpath = actseq->strip ? actseq->strip->dirpath : nullptr;
 
  if (!SEQ_USE_DATA(actseq)) {
    return changed;
  }
 
  if (SEQ_HAS_PATH(actseq) && dirpath) {
    for (Sequence *seq : strips) {
      if (SEQ_CHANNEL_CHECK(seq, channel) && SEQ_HAS_PATH(seq) && seq->strip &&
          STREQ(seq->strip->dirpath, dirpath))
      {
        seq->flag |= SELECT;
        changed = true;
      }
    }
  }
  else if (actseq->type == SEQ_TYPE_SCENE) {
    Scene *sce = actseq->scene;
    for (Sequence *seq : strips) {
      if (SEQ_CHANNEL_CHECK(seq, channel) && seq->type == SEQ_TYPE_SCENE && seq->scene == sce) {
        seq->flag |= SELECT;
        changed = true;
      }
    }
  }
  else if (actseq->type == SEQ_TYPE_MOVIECLIP) {
    MovieClip *clip = actseq->clip;
    for (Sequence *seq : strips) {
      if (SEQ_CHANNEL_CHECK(seq, channel) && seq->type == SEQ_TYPE_MOVIECLIP && seq->clip == clip)
      {
        seq->flag |= SELECT;
        changed = true;
      }
    }
  }
  else if (actseq->type == SEQ_TYPE_MASK) {
    Mask *mask = actseq->mask;
    for (Sequence *seq : strips) {
      if (SEQ_CHANNEL_CHECK(seq, channel) && seq->type == SEQ_TYPE_MASK && seq->mask == mask) {
        seq->flag |= SELECT;
        changed = true;
      }
    }
  }
 
  return changed;
}
 
static bool select_grouped_effect(blender::Span<Sequence *> strips,
                                  ListBase * /*seqbase*/,
                                  Sequence *actseq,
                                  const int channel)
{
  bool changed = false;
  bool effects[SEQ_TYPE_MAX + 1];
 
  for (int i = 0; i <= SEQ_TYPE_MAX; i++) {
    effects[i] = false;
  }
 
  for (Sequence *seq : strips) {
    if (SEQ_CHANNEL_CHECK(seq, channel) && (seq->type & SEQ_TYPE_EFFECT) &&
        SEQ_relation_is_effect_of_strip(seq, actseq))
    {
      effects[seq->type] = true;
    }
  }
 
  for (Sequence *seq : strips) {
    if (SEQ_CHANNEL_CHECK(seq, channel) && effects[seq->type]) {
      if (seq->seq1) {
        seq->seq1->flag |= SELECT;
      }
      if (seq->seq2) {
        seq->seq2->flag |= SELECT;
      }
      changed = true;
    }
  }
 
  return changed;
}
 
static bool select_grouped_time_overlap(const Scene *scene,
                                        blender::Span<Sequence *> strips,
                                        ListBase * /*seqbase*/,
                                        Sequence *actseq)
{
  bool changed = false;
 
  for (Sequence *seq : strips) {
    if (SEQ_time_left_handle_frame_get(scene, seq) <
            SEQ_time_right_handle_frame_get(scene, actseq) &&
        SEQ_time_right_handle_frame_get(scene, seq) >
            SEQ_time_left_handle_frame_get(scene, actseq))
    {
      seq->flag |= SELECT;
      changed = true;
    }
  }
 
  return changed;
}
 
/* Query strips that are in lower channel and intersect in time with seq_reference. */
static void query_lower_channel_strips(const Scene *scene,
                                       Sequence *seq_reference,
                                       ListBase *seqbase,
                                       blender::VectorSet<Sequence *> &strips)
{
  LISTBASE_FOREACH (Sequence *, seq_test, seqbase) {
    if (seq_test->machine > seq_reference->machine) {
      continue; /* Not lower channel. */
    }
    if (SEQ_time_right_handle_frame_get(scene, seq_test) <=
            SEQ_time_left_handle_frame_get(scene, seq_reference) ||
        SEQ_time_left_handle_frame_get(scene, seq_test) >=
            SEQ_time_right_handle_frame_get(scene, seq_reference))
    {
      continue; /* Not intersecting in time. */
    }
    strips.add(seq_test);
  }
}
 
/* Select all strips within time range and with lower channel of initial selection. Then select
 * effect chains of these strips. */
static bool select_grouped_effect_link(const Scene *scene,
                                       blender::VectorSet<Sequence *> strips,
                                       ListBase *seqbase,
                                       Sequence * /*actseq*/,
                                       const int /*channel*/)
{
  /* Get collection of strips. */
  strips.remove_if([&](Sequence *seq) { return (seq->flag & SELECT) == 0; });
  const int selected_strip_count = strips.size();
  /* XXX: this uses scene as arg, so it does not work with iterator :( I had thought about this,
   * but expand function is just so useful... I can just add scene and inject it I guess. */
  SEQ_iterator_set_expand(scene, seqbase, strips, query_lower_channel_strips);
  SEQ_iterator_set_expand(scene, seqbase, strips, SEQ_query_strip_effect_chain);
 
  /* Check if other strips will be affected. */
  const bool changed = strips.size() > selected_strip_count;
 
  /* Actual logic. */
  for (Sequence *seq : strips) {
    seq->flag |= SELECT;
  }
 
  return changed;
}
 
#undef SEQ_IS_SOUND
#undef SEQ_IS_EFFECT
#undef SEQ_USE_DATA
 
static int sequencer_select_grouped_exec(bContext *C, wmOperator *op)
{
  Scene *scene = CTX_data_scene(C);
  ListBase *seqbase = SEQ_active_seqbase_get(SEQ_editing_get(scene));
  Sequence *actseq = SEQ_select_active_get(scene);
 
  const bool is_preview = sequencer_view_has_preview_poll(C);
  if (is_preview && !sequencer_view_preview_only_poll(C)) {
    return OPERATOR_CANCELLED;
  }
 
  blender::VectorSet strips = all_strips_from_context(C);
 
  if (actseq == nullptr || (is_preview && !strips.contains(actseq))) {
    BKE_report(op->reports, RPT_ERROR, "No active sequence!");
    return OPERATOR_CANCELLED;
  }
 
  const int type = RNA_enum_get(op->ptr, "type");
  const int channel = RNA_boolean_get(op->ptr, "use_active_channel") ? actseq->machine : 0;
  const bool extend = RNA_boolean_get(op->ptr, "extend");
 
  bool changed = false;
 
  if (!extend) {
    LISTBASE_FOREACH (Sequence *, seq, seqbase) {
      seq->flag &= ~SELECT;
      changed = true;
    }
  }
 
  switch (type) {
    case SEQ_SELECT_GROUP_TYPE:
      changed |= select_grouped_type(strips, seqbase, actseq, channel);
      break;
    case SEQ_SELECT_GROUP_TYPE_BASIC:
      changed |= select_grouped_type_basic(strips, seqbase, actseq, channel);
      break;
    case SEQ_SELECT_GROUP_TYPE_EFFECT:
      changed |= select_grouped_type_effect(strips, seqbase, actseq, channel);
      break;
    case SEQ_SELECT_GROUP_DATA:
      changed |= select_grouped_data(strips, seqbase, actseq, channel);
      break;
    case SEQ_SELECT_GROUP_EFFECT:
      changed |= select_grouped_effect(strips, seqbase, actseq, channel);
      break;
    case SEQ_SELECT_GROUP_EFFECT_LINK:
      changed |= select_grouped_effect_link(scene, strips, seqbase, actseq, channel);
      break;
    case SEQ_SELECT_GROUP_OVERLAP:
      changed |= select_grouped_time_overlap(scene, strips, seqbase, actseq);
      break;
    default:
      BLI_assert(0);
      break;
  }
 
  if (changed) {
    ED_outliner_select_sync_from_sequence_tag(C);
    WM_event_add_notifier(C, NC_SCENE | ND_SEQUENCER | NA_SELECTED, scene);
    return OPERATOR_FINISHED;
  }
 
  return OPERATOR_CANCELLED;
}
 
void SEQUENCER_OT_select_grouped(wmOperatorType *ot)
{
  /* Identifiers. */
  ot->name = "Select Grouped";
  ot->idname = "SEQUENCER_OT_select_grouped";
  ot->description = "Select all strips grouped by various properties";
 
  /* Api callbacks. */
  ot->invoke = WM_menu_invoke;
  ot->exec = sequencer_select_grouped_exec;
  ot->poll = sequencer_edit_poll;
 
  /* Flags. */
  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 
  /* Properties. */
  ot->prop = RNA_def_enum(ot->srna, "type", sequencer_prop_select_grouped_types, 0, "Type", "");
  RNA_def_boolean(ot->srna,
                  "extend",
                  false,
                  "Extend",
                  "Extend selection instead of deselecting everything first");
  RNA_def_boolean(ot->srna,
                  "use_active_channel",
                  false,
                  "Same Channel",
                  "Only consider strips on the same channel as the active one");
}