[pitivi] timeline: Support deleting a clip and shifting following ones

[Alexandru Băluț <alexbalut src gnome org>]

commit fa15e48aa65d93db67764e5bd8609b93f161e12a
Author: Michał Górny <mgorny gentoo org>
Date:   Mon Sep 25 22:49:18 2017 +0200

    timeline: Support deleting a clip and shifting following ones
    
    Add a new function to delete selected clips with shifting the clips
    following them, accessible via shift+del. Shifting is only performed if
    no other clips overlap with the removed clips, and is done by the length
    of continuous removed interval.
    
    https://phabricator.freedesktop.org/T7832

 pitivi/timeline/timeline.py |   49 +++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 49 insertions(+), 0 deletions(-)
---
diff --git a/pitivi/timeline/timeline.py b/pitivi/timeline/timeline.py
index d2c7e2f..d20ed23 100644
--- a/pitivi/timeline/timeline.py
+++ b/pitivi/timeline/timeline.py
@@ -1417,6 +1417,7 @@ class TimelineContainer(Gtk.Grid, Zoomable, Loggable):
     def updateActions(self):
         selection_non_empty = bool(self.timeline.selection)
         self.delete_action.set_enabled(selection_non_empty)
+        self.delete_and_shift_action.set_enabled(selection_non_empty)
         self.group_action.set_enabled(selection_non_empty)
         self.ungroup_action.set_enabled(selection_non_empty)
         self.copy_action.set_enabled(selection_non_empty)
@@ -1507,6 +1508,12 @@ class TimelineContainer(Gtk.Grid, Zoomable, Loggable):
         self.app.shortcuts.add("timeline.delete-selected-clips", ["Delete"],
                                _("Delete selected clips"))
 
+        self.delete_and_shift_action = Gio.SimpleAction.new("delete-selected-clips-and-shift", None)
+        self.delete_and_shift_action.connect("activate", self._delete_selected_and_shift)
+        group.add_action(self.delete_and_shift_action)
+        self.app.shortcuts.add("timeline.delete-selected-clips-and-shift", ["<Shift>Delete"],
+                               _("Delete selected clips and shift following ones"))
+
         self.group_action = Gio.SimpleAction.new("group-selected-clips", None)
         self.group_action.connect("activate", self._group_selected_cb)
         group.add_action(self.group_action)
@@ -1635,6 +1642,48 @@ class TimelineContainer(Gtk.Grid, Zoomable, Loggable):
 
             self.timeline.selection.setSelection([], SELECT)
 
+    def _delete_selected_and_shift(self, unused_action, unused_parameter):
+        if self.ges_timeline:
+            with self.app.action_log.started("delete clip and shift",
+                                             
finalizing_action=CommitTimelineFinalizingAction(self._project.pipeline),
+                                             toplevel=True):
+                start = []
+                end = []
+
+                # remove the clips and store their start/end positions
+                for clip in self.timeline.selection:
+                    if isinstance(clip, GES.TransitionClip):
+                        continue
+                    layer = clip.get_layer()
+                    start.append(clip.start)
+                    end.append(clip.start + clip.duration)
+                    layer.remove_clip(clip)
+
+                if start:
+                    start = min(start)
+                    end = max(end)
+                    found_overlapping = False
+
+                    # check if any other clips occur during that period
+                    for layer in self.ges_timeline.layers:
+                        for clip in layer.get_clips():
+                            clip_end = clip.start + clip.duration
+                            if clip_end > start and clip.start < end:
+                                found_overlapping = True
+                                break
+                        if found_overlapping:
+                            break
+
+                    if not found_overlapping:
+                        # now shift everything following cut time
+                        shift_by = end - start
+                        for layer in self.ges_timeline.layers:
+                            for clip in layer.get_clips():
+                                if clip.start >= end:
+                                    clip.set_start(clip.start - shift_by)
+
+            self.timeline.selection.setSelection([], SELECT)
+
     def _ungroup_selected_cb(self, unused_action, unused_parameter):
         if not self.ges_timeline:
             self.info("No ges_timeline set yet!")