ROADMAP.md

Feature: Undo

• setup empty undo[] array
• setup currentUndo index value
• when .save() is called, snapshot the tiles[] array and unshift it onto undo[]; update currentUndo = 0
• when ctrl+z is fired, update this.currentUndo += 1; assign this.tiles = this.undo[this.currentUndo]
• when ctrl+shift+z is fired, update this.currentUndo -= 1; assign this.tiles = this.undo[this.currentUndo]

Notes:

• need a macro for undoAction(direction) where direction = +-1

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