/** @return operation that reverts the effect of the latest local operation in the given editor */
protected Operation calcUndoOperation(SPath editor) {
if (!undoHistory.canUndo(editor)) return new NoOperation(); // nothing to undo
Operation lastLocal = undoHistory.getLatestLocal(editor);
assert lastLocal != null;
Operation undoOperation = lastLocal.invert();
for (EditorHistoryEntry entry : undoHistory.entriesToLatestLocal(editor)) {
Operation operation = entry.getOperation();
undoOperation = transformation.transform(undoOperation, operation, Boolean.TRUE);
log.debug("transformed undo: " + undoOperation);
}
undoHistory.replaceType(editor, lastLocal, Type.LOCAL, Type.REMOTE);
// it is not relevant any more, so it is set remote
undoHistory.add(editor, Type.REDOABLE, undoOperation); // save for redo
return undoOperation;
}
/** @return operation that reverts the effect of the latest undo in the given editor */
protected Operation calcRedoOperation(SPath editor) {
if (!undoHistory.canRedo(editor)) return new NoOperation(); // nothing to redo
Operation lastUndo = undoHistory.getLatestRedoable(editor);
assert lastUndo != null;
Operation redoOperation = lastUndo.invert();
for (EditorHistoryEntry entry : undoHistory.entriesToLatestRedoable(editor)) {
redoOperation = transformation.transform(redoOperation, entry.getOperation(), Boolean.TRUE);
}
undoHistory.replaceType(editor, lastUndo, Type.REDOABLE, Type.REMOTE);
// it is not relevant any more, so it is set remote
undoHistory.add(editor, Type.LOCAL, redoOperation);
log.debug("adding " + lastUndo + " (cause: redo internal)");
return redoOperation;
}
