[gnome-music/wip/jfelder/songeditor-gtk4: 25/32] selectiontoolbar: Add support to launch song editor dialog

[Jean Felder <jfelder src gnome org>]

commit c3c34b6df85e3eb8095f18b7fd4341baa6048671
Author: Sumaid Syed <sumaidsyed gmail com>
Date:   Thu Jan 23 14:18:55 2020 +0100

    selectiontoolbar: Add support to launch song editor dialog
    
    This dialog can be displayed if only one song is selected.
    
    Based on an initial patch by Jean Felder.

 data/ui/SelectionToolbar.ui            |  8 ++++++++
 gnomemusic/widgets/selectiontoolbar.py | 16 +++++++++++-----
 gnomemusic/window.py                   | 21 +++++++++++++++++++++
 3 files changed, 40 insertions(+), 5 deletions(-)
---
diff --git a/data/ui/SelectionToolbar.ui b/data/ui/SelectionToolbar.ui
index 852b73676..b1f4dd18d 100644
--- a/data/ui/SelectionToolbar.ui
+++ b/data/ui/SelectionToolbar.ui
@@ -12,5 +12,13 @@
         <signal name="clicked" handler="_on_add_to_playlist_button_clicked" swapped="no"/>
       </object>
     </child>
+    <child>
+      <object class="GtkButton" id="_edit_details_button">
+        <property name="label" translatable="yes">Edit Details</property>
+        <property name="sensitive">False</property>
+        <property name="receives_default">True</property>
+        <signal name="clicked" handler="_on_edit_tags_button_clicked" swapped="no"/>
+      </object>
+    </child>
   </template>
 </interface>
diff --git a/gnomemusic/widgets/selectiontoolbar.py b/gnomemusic/widgets/selectiontoolbar.py
index f3a34bc4a..439b50f7a 100644
--- a/gnomemusic/widgets/selectiontoolbar.py
+++ b/gnomemusic/widgets/selectiontoolbar.py
@@ -31,9 +31,11 @@ class SelectionToolbar(Gtk.ActionBar):
     __gtype_name__ = 'SelectionToolbar'
 
     _add_to_playlist_button = Gtk.Template.Child()
+    _edit_details_button = Gtk.Template.Child()
 
     __gsignals__ = {
-        'add-to-playlist': (GObject.SignalFlags.RUN_FIRST, None, ())
+        'add-to-playlist': (GObject.SignalFlags.RUN_FIRST, None, ()),
+        "edit-details": (GObject.SignalFlags.RUN_FIRST, None, ())
     }
 
     selected_songs_count = GObject.Property(type=int, default=0, minimum=0)
@@ -50,8 +52,12 @@ class SelectionToolbar(Gtk.ActionBar):
     def _on_add_to_playlist_button_clicked(self, widget):
         self.emit('add-to-playlist')
 
+    @Gtk.Template.Callback()
+    def _on_edit_tags_button_clicked(self, widget):
+        self.emit("edit-details")
+
     def _on_songs_selection_changed(self, widget, data):
-        if self.props.selected_songs_count > 0:
-            self._add_to_playlist_button.props.sensitive = True
-        else:
-            self._add_to_playlist_button.props.sensitive = False
+        selection_size: int = self.props.selected_songs_count
+
+        self._add_to_playlist_button.props.sensitive = (selection_size > 0)
+        self._edit_details_button.props.sensitive = (selection_size == 1)
diff --git a/gnomemusic/window.py b/gnomemusic/window.py
index a79753817..a48187f55 100644
--- a/gnomemusic/window.py
+++ b/gnomemusic/window.py
@@ -44,6 +44,7 @@ from gnomemusic.widgets.playertoolbar import PlayerToolbar  # noqa: F401
 from gnomemusic.widgets.playlistdialog import PlaylistDialog
 from gnomemusic.widgets.searchheaderbar import SearchHeaderBar
 from gnomemusic.widgets.selectiontoolbar import SelectionToolbar  # noqa: F401
+from gnomemusic.widgets.songeditordialog import SongEditorDialog
 from gnomemusic.windowplacement import WindowPlacement
 
 
@@ -165,6 +166,7 @@ class Window(Adw.ApplicationWindow):
 
         self._selection_toolbar.connect(
             'add-to-playlist', self._on_add_to_playlist)
+        self._selection_toolbar.connect("edit-details", self._on_edit_tags)
         self._search.connect("notify::state", self._on_search_state_changed)
 
         self._headerbar.props.state = HeaderBar.State.MAIN
@@ -471,6 +473,25 @@ class Window(Adw.ApplicationWindow):
         self._playlist_dialog.connect("response", on_response)
         self._playlist_dialog.present()
 
+    def _on_edit_tags(self, widget: SelectionToolbar) -> None:
+        def on_response(dialog: PlaylistDialog, response_id: int) -> None:
+            self.props.selection_mode = False
+            song_editor_dialog.destroy()
+
+        if self._stack.get_visible_child() == self.views[View.PLAYLIST]:
+            return
+
+        coreselection = self._app.props.coreselection
+        selected_songs = coreselection.props.selected_songs
+
+        if len(selected_songs) < 1:
+            return
+
+        song_editor_dialog = SongEditorDialog(self._app, selected_songs[0])
+        song_editor_dialog.props.transient_for = self
+        song_editor_dialog.connect("response", on_response)
+        song_editor_dialog.present()
+
     def set_player_visible(self, visible):
         """Set PlayWidget action visibility