safe gltf with fontcollection objects

__init__.py

@@ -328,14 +328,69 @@ class FONT3D_OT_SaveFontToFile(bpy.types.Operator):
         font3d_data = scene.font3d_data
         font3d = scene.font3d
 
-        selected_font = font3d_data.available_fonts[font3d_data.active_font_index]
+        fontcollection = bpy.data.collections.get("Font3D")
 
-        print(selected_font.font_name)
+        # needed to restore current state later
+        fontcollection_was_linked = False
+        previous_objects = []
+        fontcollection_objects = []
+
+        # hide fontcollection
+        if fontcollection is None:
+            self.report({'INFO'}, f"{bl_info['name']}: There is no collection")
+            return {'CANCELLED'}
+        elif scene.collection.children.find(fontcollection.name) > 0:
+            scene.collection.children.unlink(fontcollection)
+            fontcollection_was_linked = True
+
+        # collect and hide previous objects
+        for o in scene.objects:
+            previous_objects.append(o)
+            scene.collection.objects.unlink(o)
+
+        # show fontcollection
+        # if scene.collection.children.find(fontcollection.name) < 0:
+            # scene.collection.children.link(fontcollection)
+        # link fontcollection
+        for o in fontcollection.objects:
+            fontcollection_objects.append(o)
+            fontcollection.objects.unlink(o)
+            scene.collection.objects.link(o)
+
+        # get save data
+        selected_font = font3d_data.available_fonts[font3d_data.active_font_index]
 
         if selected_font == "":
             butils.ShowMessageBox("Warning", 'ERROR', "no font selected")
             return {'CANCELLED'}
 
+        print(selected_font.font_name)
+        # save as gltf
+        bpy.ops.export_scene.gltf(
+            filepath="/home/jrkb/Downloads/toast/maker.gltf",
+            check_existing=False,
+            export_format='GLTF_SEPARATE',
+            export_extras=True,
+            export_hierarchy_full_collections=True,
+            use_active_collection_with_nested=True,
+        )
+
+        # restore from previous state
+        def restore():
+            for o in scene.objects:
+                scene.collection.objects.unlink(o)
+
+            for o in previous_objects:
+                scene.collection.objects.link(o)
+
+            for o in fontcollection_objects:
+                fontcollection.objects.link(o)
+
+            if fontcollection_was_linked:
+                scene.collection.children.link(fontcollection)
+
+        bpy.app.timers.register(restore, first_interval=5)
+
         return {'FINISHED'}