rekordbox_set_list_manager.controllers.undo_stack

Generic JSON-snapshot undo/redo stack.

Classes

UndoStack

Undo/redo stack that stores serialised snapshots of type T.

Module Contents

class rekordbox_set_list_manager.controllers.undo_stack.UndoStack[T](max_size=_DEFAULT_MAX)

Undo/redo stack that stores serialised snapshots of type T.

Usage:

stack: UndoStack[str] = UndoStack()

# Before a mutation:
stack.push(current_snapshot)

# Undo:
prev = stack.undo(current_snapshot)

# Redo:
next_ = stack.redo(current_snapshot)

Parameters:

max_size (int)

property can_undo: bool

Return True if there are undo steps available.

Return type:

bool

property can_redo: bool

Return True if there are redo steps available.

Return type:

bool

push(snapshot)

Record snapshot before a mutation. Clears the redo stack.

Parameters:

snapshot (T) – The serialised project state to push onto the undo history.

Return type:

None

undo(current)

Undo one step. Returns the previous snapshot, or None if empty.

The caller must pass the current snapshot so it can be pushed to the redo stack.

Parameters:

current (T) – The current serialised state, saved to the redo stack.

Returns:

The previous snapshot to restore, or None if the undo stack is empty.

Return type:

T | None

redo(current)

Redo one step. Returns the next snapshot, or None if empty.

The caller must pass the current snapshot so it can be pushed back to the undo stack.

Parameters:

current (T) – The current serialised state, saved back to the undo stack.

Returns:

The next snapshot to restore, or None if the redo stack is empty.

Return type:

T | None

clear()

Discard all undo and redo history.

Return type:

None