edit-dialog: implement moving events between sources

After adding the button in the headerbar, it is natural to
bring back the ability to move events between sources.

This commit finally includes the usage of GcalManager:move_event_to_source
function, which was implemented ages ago.

src/gcal-edit-dialog.c

@@ -77,6 +77,7 @@ struct _GcalEditDialog
 
   /* new data holders */
   GcalEvent        *event;
+  ESource          *selected_source;
 
   /* flags */
   gboolean          format_24h;
@@ -191,13 +192,13 @@ on_calendar_selected (GSimpleAction *action,
                       GVariant      *value,
                       gpointer       user_data)
 {
-  GcalEditDialog *dialog;
+  GcalEditDialog *self;
   GList *list;
   GList *aux;
   gchar *uid;
 
-  dialog = GCAL_EDIT_DIALOG (user_data);
+  self = GCAL_EDIT_DIALOG (user_data);
-  list = gcal_manager_get_sources (dialog->manager);
+  list = gcal_manager_get_sources (self->manager);
 
   /* retrieve selected calendar uid */
   g_variant_get (value, "s", &uid);
@@ -217,11 +218,12 @@ on_calendar_selected (GSimpleAction *action,
         get_color_name_from_source (source, &color);
 
         pix = gcal_get_pixbuf_from_color (&color, 16);
-        gtk_image_set_from_pixbuf (GTK_IMAGE (dialog->source_image), pix);
+        gtk_image_set_from_pixbuf (GTK_IMAGE (self->source_image), pix);
         g_object_unref (pix);
 
-        gcal_event_set_source (dialog->event, source);
+        self->selected_source = source;
-        gtk_header_bar_set_subtitle (GTK_HEADER_BAR (dialog->titlebar),
+
+        gtk_header_bar_set_subtitle (GTK_HEADER_BAR (self->titlebar),
                                      e_source_get_display_name (source));
         break;
       }
@@ -589,6 +591,29 @@ gcal_edit_dialog_action_button_clicked (GtkWidget *widget,
       g_clear_pointer (&start_date, g_date_time_unref);
       g_clear_pointer (&end_date, g_date_time_unref);
 
+      /* Update the source if needed */
+      if (dialog->selected_source &&
+          gcal_event_get_source (dialog->event) != dialog->selected_source)
+        {
+          /*
+           * When we're creating the event, it has no source set, so we simply
+           * set the source. When editing the event, however, we're actually
+           * moving it from one source to another.
+           */
+          if (!gcal_event_get_source (dialog->event))
+            {
+              gcal_event_set_source (dialog->event, dialog->selected_source);
+            }
+          else
+            {
+              gcal_manager_move_event_to_source (dialog->manager,
+                                                 dialog->event,
+                                                 dialog->selected_source);
+            }
+        }
+
+      dialog->selected_source = NULL;
+
       /* Send the response */
       gtk_dialog_response (GTK_DIALOG (dialog),
                            dialog->event_is_new ? GCAL_RESPONSE_CREATE_EVENT : GCAL_RESPONSE_SAVE_EVENT);
@@ -955,10 +980,6 @@ gcal_edit_dialog_set_event_is_new (GcalEditDialog *dialog,
   dialog->event_is_new = event_is_new;
 
   gtk_widget_set_visible (dialog->delete_button, !event_is_new);
-
-  /* FIXME: implement moving events to other sources */
-  gtk_widget_set_sensitive (dialog->sources_button, event_is_new);
-  gtk_button_set_relief (GTK_BUTTON (dialog->sources_button), event_is_new ? GTK_RELIEF_NORMAL : GTK_RELIEF_NONE);
 }
 
 GcalEvent*