letsfindaway
commented
2 years ago Note that the second point needs careful evaluation for several reasons:
- Currently objects like images etc assume that there is a 1:1 relationship between the item on the scene and the image file. When the item is deleted, the file will be deleted. Reusing such a file would indeed require that all such operations go through a foreign object manager which knows about the usage of a file.
- When opening a document with a previous version of OpenBoard, then this version is not aware of that and might delete objects which are still referenced from elsewhere.
So I think it would be too dangerous to do this optimization. And then also the first step is not needed. So finally we would end up with the last step doing a cleanup of unreferenced files.
For the third point note that there is no "save document" function. The UBPersistenceManager only handles scenes, not documents for saving. An idea is to execute this function on the very first call to UBPersistenceManager::persistDocumentScene for a document. This would need a flag in the UBDocumentProxy to mark whether the cleanup was already performed. Implementation of the operation should be in the UBPersistenceManager. It knows about the naming of scene files and already has the private: static QStringList getSceneFileNames(const QString& folder) function, which is very helpful for this.
To solve issue https://github.com/OpenBoard-org/OpenBoard/issues/671, problem 2 I propose to add a
ForeignObjectManager, which keeps track of the objects in a document and their usage. It could probably do the following:objects,videosandaudiosdirectories and creates a list of UUIDs and document sizes (as a very first rough and easy to collect identifier).page<nnn>.svgfiles for any referenced UUIDs. This creates a list of referenced objects. All existing, but not referred objects are then deleted from the document.