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audio_streamview.cc

/*
    Copyright (C) 2001, 2006 Paul Davis 

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include <cmath>
#include <cassert>

#include <gtkmm.h>

#include <gtkmm2ext/gtk_ui.h>

#include <ardour/audioplaylist.h>
#include <ardour/audioregion.h>
#include <ardour/audiofilesource.h>
#include <ardour/audio_diskstream.h>
#include <ardour/audio_track.h>
#include <ardour/playlist_templates.h>
#include <ardour/source.h>
#include <ardour/region_factory.h>
#include <ardour/profile.h>

#include "audio_streamview.h"
#include "audio_region_view.h"
#include "tape_region_view.h"
#include "audio_time_axis.h"
#include "canvas-waveview.h"
#include "canvas-simplerect.h"
#include "region_selection.h"
#include "selection.h"
#include "public_editor.h"
#include "ardour_ui.h"
#include "crossfade_view.h"
#include "rgb_macros.h"
#include "gui_thread.h"
#include "utils.h"

#include "i18n.h"

using namespace ARDOUR;
using namespace PBD;
using namespace Editing;

AudioStreamView::AudioStreamView (AudioTimeAxisView& tv)
      : StreamView (tv)
{
      crossfades_visible = true;
      _waveform_scale = LinearWaveform;
      _waveform_shape = Traditional;

      color_handler ();

      _amplitude_above_axis = 1.0;

      use_rec_regions = tv.editor.show_waveforms_recording ();
      last_rec_peak_frame = 0;

}

AudioStreamView::~AudioStreamView ()
{
}

int
AudioStreamView::set_height (gdouble h)
{
      /* limit the values to something sane-ish */
      if (h < 10.0 || h > 1000.0) {
            return -1;
      }

      StreamView::set_height(h);

      for (CrossfadeViewList::iterator i = crossfade_views.begin(); i != crossfade_views.end(); ++i) {
            (*i)->set_height (h);
      }

      return 0;
}

int 
AudioStreamView::set_samples_per_unit (gdouble spp)
{
      StreamView::set_samples_per_unit(spp);

      for (CrossfadeViewList::iterator xi = crossfade_views.begin(); xi != crossfade_views.end(); ++xi) {
            (*xi)->set_samples_per_unit (spp);
      }

      return 0;
}

int 
AudioStreamView::set_amplitude_above_axis (gdouble app)
{
      RegionViewList::iterator i;

      if (app < 1.0) {
            return -1;
      }

      _amplitude_above_axis = app;

      for (i = region_views.begin(); i != region_views.end(); ++i) {
            AudioRegionView* const arv = dynamic_cast<AudioRegionView*>(*i);
            if (arv)
                  arv->set_amplitude_above_axis (app);
      }

      return 0;
}

void
AudioStreamView::add_region_view_internal (boost::shared_ptr<Region> r, bool wait_for_waves, bool recording)
{
      AudioRegionView *region_view = 0;

      ENSURE_GUI_THREAD (bind (mem_fun (*this, &AudioStreamView::add_region_view), r));

      boost::shared_ptr<AudioRegion> region = boost::dynamic_pointer_cast<AudioRegion> (r);

      if (region == 0) {
            return;
      }

      for (list<RegionView *>::iterator i = region_views.begin(); i != region_views.end(); ++i) {
            if ((*i)->region() == r) {
                  
                  /* great. we already have a AudioRegionView for this Region. use it again. */
                  
                  (*i)->set_valid (true);

                  // this might not be necessary
                  AudioRegionView* const arv = dynamic_cast<AudioRegionView*>(*i);
                  if (arv) {
                        arv->set_waveform_scale (_waveform_scale);
                        arv->set_waveform_shape (_waveform_shape);
                  }
                        
                  return;
            }
      }

      switch (_trackview.audio_track()->mode()) {
      case Normal:
            if (recording) {
                  region_view = new AudioRegionView (canvas_group, _trackview, region, 
                                       _samples_per_unit, region_color, recording, TimeAxisViewItem::Visibility(TimeAxisViewItem::ShowFrame | TimeAxisViewItem::HideFrameRight));
            } else {
                  region_view = new AudioRegionView (canvas_group, _trackview, region, 
                                             _samples_per_unit, region_color);
            }
            break;
      case Destructive:
            region_view = new TapeAudioRegionView (canvas_group, _trackview, region, 
                                           _samples_per_unit, region_color);
            break;
      default:
            fatal << string_compose (_("programming error: %1"), "illegal track mode in ::add_region_view_internal") << endmsg;
            /*NOTREACHED*/

      }

      region_view->init (region_color, wait_for_waves);
      region_view->set_amplitude_above_axis(_amplitude_above_axis);
      region_views.push_front (region_view);

      /* if its the special single-sample length that we use for rec-regions, make it 
         insensitive to events 
      */

      if (region->length() == 1) {
            region_view->set_sensitive (false);
      }

      /* if this was the first one, then lets query the waveform scale and shape.
         otherwise, we set it to the current value */
         
      if (region_views.size() == 1) {
            if (region_view->waveform_logscaled()) {
                  _waveform_scale = LogWaveform;
            } else {
                  _waveform_scale = LinearWaveform;
            }

            if (region_view->waveform_rectified()) {
                  _waveform_shape = Rectified;
            } else {
                  _waveform_shape = Traditional;
            }
      }
      else {
            region_view->set_waveform_scale(_waveform_scale);
            region_view->set_waveform_shape(_waveform_shape);
      }
      
      /* follow global waveform setting */

      region_view->set_waveform_visible(_trackview.editor.show_waveforms());

      /* catch regionview going away */
      region->GoingAway.connect (bind (mem_fun (*this, &AudioStreamView::remove_region_view), boost::weak_ptr<Region> (r)));

      RegionViewAdded (region_view);
}

void
AudioStreamView::remove_region_view (boost::weak_ptr<Region> weak_r)
{
      ENSURE_GUI_THREAD (bind (mem_fun (*this, &AudioStreamView::remove_region_view), weak_r));

      boost::shared_ptr<Region> r (weak_r.lock());

      if (!r) {
            return;
      }

      if (!_trackview.session().deletion_in_progress()) {

            for (list<CrossfadeView *>::iterator i = crossfade_views.begin(); i != crossfade_views.end();) {
                  list<CrossfadeView*>::iterator tmp;
                  
                  tmp = i;
                  ++tmp;
                  
                  boost::shared_ptr<AudioRegion> ar = boost::dynamic_pointer_cast<AudioRegion>(r);
                  if (ar && (*i)->crossfade->involves (ar)) {
                        delete *i;
                        crossfade_views.erase (i);
                  }
                  
                  i = tmp;
            }
      }


      StreamView::remove_region_view(r);
}

void
AudioStreamView::undisplay_diskstream ()
{
      StreamView::undisplay_diskstream();

      for (CrossfadeViewList::iterator i = crossfade_views.begin(); i != crossfade_views.end(); ++i) {
            delete *i;
      }

      crossfade_views.clear ();
}

void
AudioStreamView::playlist_modified ()
{
      ENSURE_GUI_THREAD (mem_fun (*this, &AudioStreamView::playlist_modified));

      StreamView::playlist_modified();
      
      /* make sure xfades are on top and all the regionviews are stacked correctly. */

      for (list<CrossfadeView *>::iterator i = crossfade_views.begin(); i != crossfade_views.end(); ++i) {
            (*i)->get_canvas_group()->raise_to_top();
      }
}

void
AudioStreamView::playlist_changed (boost::weak_ptr<Diskstream> wptr)
{
      ENSURE_GUI_THREAD (bind (mem_fun (*this, &AudioStreamView::playlist_changed), wptr));

      boost::shared_ptr<Diskstream> ds  = wptr.lock();

      if (!ds) {
            return;
      }

      StreamView::playlist_changed(ds);

      boost::shared_ptr<AudioPlaylist> apl = boost::dynamic_pointer_cast<AudioPlaylist>(ds->playlist());
      if (apl)
            playlist_connections.push_back (apl->NewCrossfade.connect (mem_fun (*this, &AudioStreamView::add_crossfade)));
}

void
AudioStreamView::add_crossfade_weak (boost::weak_ptr<Crossfade> crossfade)
{
      boost::shared_ptr<Crossfade> sp (crossfade.lock());

      if (!sp) {
            return;
      }

      add_crossfade (sp);
}

void
AudioStreamView::add_crossfade (boost::shared_ptr<Crossfade> crossfade)
{
      AudioRegionView* lview = 0;
      AudioRegionView* rview = 0;

      /* we do not allow shared_ptr<T> to be bound to slots */
      
      ENSURE_GUI_THREAD (bind (mem_fun (*this, &AudioStreamView::add_crossfade_weak), boost::weak_ptr<Crossfade> (crossfade)));

      /* first see if we already have a CrossfadeView for this Crossfade */

      for (list<CrossfadeView *>::iterator i = crossfade_views.begin(); i != crossfade_views.end(); ++i) {
            if ((*i)->crossfade == crossfade) {
                  if (!crossfades_visible) {
                        (*i)->hide();
                  } else {
                        (*i)->show ();
                  }
                  (*i)->set_valid (true);
                  return;
            }
      }

      /* create a new one */

      for (list<RegionView *>::iterator i = region_views.begin(); i != region_views.end(); ++i) {
            AudioRegionView* arv = dynamic_cast<AudioRegionView*>(*i);

            if (!lview && arv && (arv->region() == crossfade->out())) {
                  lview = arv;
            }
            if (!rview && arv && (arv->region() == crossfade->in())) {
                  rview = arv;
            }
      }

      CrossfadeView *cv = new CrossfadeView (_trackview.canvas_display,
                                     _trackview,
                                      crossfade,
                                     _samples_per_unit,
                                     region_color,
                                     *lview, *rview);

      crossfade->Invalidated.connect (mem_fun (*this, &AudioStreamView::remove_crossfade));
      crossfade_views.push_back (cv);

      if (!Config->get_xfades_visible() || !crossfades_visible) {
            cv->hide ();
      }
}

void
AudioStreamView::remove_crossfade (boost::shared_ptr<Crossfade> xfade)
{
      ENSURE_GUI_THREAD (bind (mem_fun (*this, &AudioStreamView::remove_crossfade), xfade));

      for (list<CrossfadeView*>::iterator i = crossfade_views.begin(); i != crossfade_views.end(); ++i) {
            if ((*i)->crossfade == xfade) {
                  delete *i;
                  crossfade_views.erase (i);
                  break;
            }
      }
}

void
AudioStreamView::redisplay_diskstream ()
{
      list<RegionView *>::iterator i, tmp;
      list<CrossfadeView*>::iterator xi, tmpx;

      for (i = region_views.begin(); i != region_views.end(); ++i) {
            (*i)->set_valid (false);
      }

      for (xi = crossfade_views.begin(); xi != crossfade_views.end(); ++xi) {
            (*xi)->set_valid (false);
            if ((*xi)->visible()) {
                  (*xi)->show ();
            }
      }

      if (_trackview.is_audio_track()) {
            _trackview.get_diskstream()->playlist()->foreach_region (static_cast<StreamView*>(this), &StreamView::add_region_view);

            boost::shared_ptr<AudioPlaylist> apl = boost::dynamic_pointer_cast<AudioPlaylist>(_trackview.get_diskstream()->playlist());
            if (apl)
                  apl->foreach_crossfade (this, &AudioStreamView::add_crossfade);
      }

      for (i = region_views.begin(); i != region_views.end(); ) {
            tmp = i;
            tmp++;

            if (!(*i)->is_valid()) {
                  delete *i;
                  region_views.erase (i);
            } 

            i = tmp;
      }

      for (xi = crossfade_views.begin(); xi != crossfade_views.end();) {
            tmpx = xi;
            tmpx++;

            if (!(*xi)->valid()) {
                  delete *xi;
                  crossfade_views.erase (xi);
            }

            xi = tmpx;
      }

      /* now fix layering */

      for (RegionViewList::iterator i = region_views.begin(); i != region_views.end(); ++i) {
            region_layered (*i);
      }
}

void
AudioStreamView::set_show_waveforms (bool yn)
{
      for (list<RegionView *>::iterator i = region_views.begin(); i != region_views.end(); ++i) {
            AudioRegionView* const arv = dynamic_cast<AudioRegionView*>(*i);
            if (arv) {
                  arv->set_waveform_visible (yn);
            }
      }
}

void
AudioStreamView::set_waveform_shape (WaveformShape shape)
{
      for (RegionViewList::iterator i = region_views.begin(); i != region_views.end(); ++i) {
            AudioRegionView* const arv = dynamic_cast<AudioRegionView*>(*i);
            if (arv)
                  arv->set_waveform_shape (shape);
      }
      _waveform_shape = shape;
}           

void
AudioStreamView::set_waveform_scale (WaveformScale scale)
{
      for (RegionViewList::iterator i = region_views.begin(); i != region_views.end(); ++i) {
            AudioRegionView* const arv = dynamic_cast<AudioRegionView*>(*i);
            if (arv) 
                  arv->set_waveform_scale (scale);
      }
      _waveform_scale = scale;
}           

void
AudioStreamView::setup_rec_box ()
{
      //cerr << _trackview.name() << " streamview SRB region_views.size() = " << region_views.size() << endl;

      if (_trackview.session().transport_rolling()) {

            // cerr << "\trolling\n";

            if (!rec_active && 
                _trackview.session().record_status() == Session::Recording && 
                _trackview.get_diskstream()->record_enabled()) {
                  if (_trackview.audio_track()->mode() == Normal && use_rec_regions && rec_regions.size() == rec_rects.size()) {

                        /* add a new region, but don't bother if they set use_rec_regions mid-record */

                        SourceList sources;

                        for (list<sigc::connection>::iterator prc = peak_ready_connections.begin(); prc != peak_ready_connections.end(); ++prc) {
                              (*prc).disconnect();
                        }
                        peak_ready_connections.clear();
                              
                        // FIXME
                        boost::shared_ptr<AudioDiskstream> ads = boost::dynamic_pointer_cast<AudioDiskstream>(_trackview.get_diskstream());
                        assert(ads);

                        for (uint32_t n=0; n < ads->n_channels(); ++n) {
                              boost::shared_ptr<AudioFileSource> src = boost::static_pointer_cast<AudioFileSource> (ads->write_source (n));
                              if (src) {
                                    sources.push_back (src);
                                    peak_ready_connections.push_back (src->PeakRangeReady.connect (bind (mem_fun (*this, &AudioStreamView::rec_peak_range_ready), boost::weak_ptr<Source>(src))));
                              }
                        }

                        // handle multi
                        
                        nframes_t start = 0;
                        if (rec_regions.size() > 0) {
                              start = rec_regions.back()->start() + _trackview.get_diskstream()->get_captured_frames(rec_regions.size()-1);
                        }
                        
                        boost::shared_ptr<AudioRegion> region (boost::dynamic_pointer_cast<AudioRegion>
                                                       (RegionFactory::create (sources, start, 1 , "", 0, (Region::Flag)(Region::DefaultFlags | Region::DoNotSaveState), false)));
                        region->set_position (_trackview.session().transport_frame(), this);

                        rec_regions.push_back (region);
                  }
                  
                  /* start a new rec box */

                  boost::shared_ptr<AudioTrack> at = _trackview.audio_track ();
                  boost::shared_ptr<AudioDiskstream> ds = at->audio_diskstream();
                  nframes_t frame_pos = ds->current_capture_start ();
                  gdouble xstart = _trackview.editor.frame_to_pixel (frame_pos);
                  gdouble xend;
                  uint32_t fill_color;

                  switch (at->mode()) {
                  case Normal:
                        xend = xstart;
                        fill_color = ARDOUR_UI::config()->canvasvar_RecordingRect.get();
                        break;

                  case Destructive:
                        xend = xstart + 2;
                        fill_color = ARDOUR_UI::config()->canvasvar_RecordingRect.get();
                        /* make the recording rect translucent to allow
                           the user to see the peak data coming in, etc.
                        */
                        fill_color = UINT_RGBA_CHANGE_A (fill_color, 120);
                        break;
                  }
                  
                  ArdourCanvas::SimpleRect * rec_rect = new Gnome::Canvas::SimpleRect (*canvas_group);
                  rec_rect->property_x1() = xstart;
                  rec_rect->property_y1() = 1.0;
                  rec_rect->property_x2() = xend;
                  rec_rect->property_y2() = (double) _trackview.current_height() - 1;
                  rec_rect->property_outline_color_rgba() = ARDOUR_UI::config()->canvasvar_TimeAxisFrame.get();
                  rec_rect->property_outline_what() = 0x1 | 0x2 | 0x4 | 0x8;
                  rec_rect->property_fill_color_rgba() = fill_color;
                  
                  RecBoxInfo recbox;
                  recbox.rectangle = rec_rect;
                  recbox.start = _trackview.session().transport_frame();
                  recbox.length = 0;
                  
                  rec_rects.push_back (recbox);
                  
                  screen_update_connection.disconnect();
                  screen_update_connection = ARDOUR_UI::instance()->SuperRapidScreenUpdate.connect (mem_fun (*this, &AudioStreamView::update_rec_box));     
                  rec_updating = true;
                  rec_active = true;

            } else if (rec_active &&
                     (_trackview.session().record_status() != Session::Recording ||
                      !_trackview.get_diskstream()->record_enabled())) {
                  screen_update_connection.disconnect();
                  rec_active = false;
                  rec_updating = false;
            }
            
      } else {

            // cerr << "\tNOT rolling, rec_rects = " << rec_rects.size() << " rec_regions = " << rec_regions.size() << endl;

            if (!rec_rects.empty() || !rec_regions.empty()) {

                  /* disconnect rapid update */
                  screen_update_connection.disconnect();

                  for (list<sigc::connection>::iterator prc = peak_ready_connections.begin(); prc != peak_ready_connections.end(); ++prc) {
                        (*prc).disconnect();
                  }
                  peak_ready_connections.clear();

                  rec_updating = false;
                  rec_active = false;
                  last_rec_peak_frame = 0;
                  
                  /* remove temp regions */

                  for (list<boost::shared_ptr<Region> >::iterator iter = rec_regions.begin(); iter != rec_regions.end(); ) {
                        list<boost::shared_ptr<Region> >::iterator tmp;

                        tmp = iter;
                        ++tmp;

                        (*iter)->drop_references ();

                        iter = tmp;
                  }
                        
                  rec_regions.clear();

                  // cerr << "\tclear " << rec_rects.size() << " rec rects\n";

                  /* transport stopped, clear boxes */
                  for (vector<RecBoxInfo>::iterator iter=rec_rects.begin(); iter != rec_rects.end(); ++iter) {
                        RecBoxInfo &rect = (*iter);
                        delete rect.rectangle;
                  }
                  
                  rec_rects.clear();
                  
            }
      }
}

void
AudioStreamView::foreach_crossfadeview (void (CrossfadeView::*pmf)(void))
{
      for (list<CrossfadeView*>::iterator i = crossfade_views.begin(); i != crossfade_views.end(); ++i) {
            ((*i)->*pmf) ();
      }
}

void
AudioStreamView::rec_peak_range_ready (nframes_t start, nframes_t cnt, boost::weak_ptr<Source> weak_src)
{
      ENSURE_GUI_THREAD(bind (mem_fun (*this, &AudioStreamView::rec_peak_range_ready), start, cnt, weak_src));
      
      boost::shared_ptr<Source> src (weak_src.lock());

      if (!src) {
            return; 
      }

      // this is called from the peak building thread
      
      if (rec_peak_ready_map.size() == 0 || start+cnt > last_rec_peak_frame) {
            last_rec_peak_frame = start + cnt;
      }
      
      rec_peak_ready_map[src] = true;
      
      if (rec_peak_ready_map.size() == _trackview.get_diskstream()->n_channels()) {
            this->update_rec_regions ();
            rec_peak_ready_map.clear();
      }
}

void
AudioStreamView::update_rec_regions ()
{
      if (use_rec_regions) {
            uint32_t n = 0;

            for (list<boost::shared_ptr<Region> >::iterator iter = rec_regions.begin(); iter != rec_regions.end(); n++) {

                  list<boost::shared_ptr<Region> >::iterator tmp;

                  tmp = iter;
                  ++tmp;

                  if (!canvas_item_visible (rec_rects[n].rectangle)) {
                        /* rect already hidden, this region is done */
                        iter = tmp;
                        continue;
                  }
                  
                  boost::shared_ptr<AudioRegion> region = boost::dynamic_pointer_cast<AudioRegion>(*iter);
                  if (!region) {
                        continue;
                  }

                  nframes_t origlen = region->length();

                  if (region == rec_regions.back() && rec_active) {

                        if (last_rec_peak_frame > region->start()) {

                              nframes_t nlen = last_rec_peak_frame - region->start();

                              if (nlen != region->length()) {

                                    region->freeze ();
                                    region->set_position (_trackview.get_diskstream()->get_capture_start_frame(n), this);
                                    region->set_length (nlen, this);
                                    region->thaw ("updated");

                                    if (origlen == 1) {
                                          /* our special initial length */
                                          add_region_view_internal (region, false, true);
                                    }

                                    /* also update rect */
                                    ArdourCanvas::SimpleRect * rect = rec_rects[n].rectangle;
                                    gdouble xend = _trackview.editor.frame_to_pixel (region->position() + region->length());
                                    rect->property_x2() = xend;
                              }
                        }

                  } else {

                        nframes_t nlen = _trackview.get_diskstream()->get_captured_frames(n);

                        if (nlen != region->length()) {

                              if (region->source(0)->length() >= region->start() + nlen) {

                                    region->freeze ();
                                    region->set_position (_trackview.get_diskstream()->get_capture_start_frame(n), this);
                                    region->set_length (nlen, this);
                                    region->thaw ("updated");
                                    
                                    if (origlen == 1) {
                                          /* our special initial length */
                                          add_region_view_internal (region, false, true);
                                    }
                                    
                                    /* also hide rect */
                                    ArdourCanvas::Item * rect = rec_rects[n].rectangle;
                                    rect->hide();

                              }
                        }
                  }

                  iter = tmp;
            }
      }
}

void
AudioStreamView::show_all_fades ()
{
      for (list<RegionView*>::iterator i = region_views.begin(); i != region_views.end(); ++i) {
            AudioRegionView* const arv = dynamic_cast<AudioRegionView*>(*i);
            if (arv) {
                  arv->set_fade_visibility (true);
            }
      }
}

void
AudioStreamView::hide_all_fades ()
{
      for (list<RegionView*>::iterator i = region_views.begin(); i != region_views.end(); ++i) {
            AudioRegionView* const arv = dynamic_cast<AudioRegionView*>(*i);
            if (arv) {
                  arv->set_fade_visibility (false);
            }
      }
}

void
AudioStreamView::show_all_xfades ()
{
      foreach_crossfadeview (&CrossfadeView::show);
      crossfades_visible = true;
}

void
AudioStreamView::hide_all_xfades ()
{
      foreach_crossfadeview (&CrossfadeView::hide);
      crossfades_visible = false;
}

void
AudioStreamView::hide_xfades_involving (AudioRegionView& rv)
{
      for (list<CrossfadeView *>::iterator i = crossfade_views.begin(); i != crossfade_views.end(); ++i) {
            if ((*i)->crossfade->involves (rv.audio_region())) {
                  (*i)->fake_hide ();
            }
      }
}

void
AudioStreamView::reveal_xfades_involving (AudioRegionView& rv)
{
      for (list<CrossfadeView *>::iterator i = crossfade_views.begin(); i != crossfade_views.end(); ++i) {
            if ((*i)->crossfade->involves (rv.audio_region()) && (*i)->visible()) {
                  (*i)->show ();
            }
      }
}

void
AudioStreamView::color_handler ()
{
      if (_trackview.is_track()) {
            canvas_rect->property_fill_color_rgba() = ARDOUR_UI::config()->canvasvar_AudioTrackBase.get();
      }

      if (!_trackview.is_track()) {
            if (Profile->get_sae() && _trackview.route()->master()) {
                  canvas_rect->property_fill_color_rgba() = ARDOUR_UI::config()->canvasvar_AudioMasterBusBase.get();
            } else {
                  canvas_rect->property_fill_color_rgba() = ARDOUR_UI::config()->canvasvar_AudioBusBase.get();
            }
      }
}


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