Files
photo-renamer/src/renderer/history.js
T

43 lines
1.1 KiB
JavaScript

const MAX = 50;
let _stack = [];
let _cursor = -1;
let _onUpdate = null;
export function setOnUpdate(fn) {
_onUpdate = fn;
}
export function push(files, affectedPaths = null) {
_stack = _stack.slice(0, _cursor + 1);
_stack.push({ files: [...files], affectedPaths: affectedPaths ? new Set(affectedPaths) : null });
if (_stack.length > MAX) _stack.shift();
_cursor = _stack.length - 1;
_onUpdate?.();
}
// Returns { files, affectedPaths } where affectedPaths are from the entry being undone
export function undo() {
if (!canUndo()) return null;
const affectedPaths = _stack[_cursor].affectedPaths;
--_cursor;
_onUpdate?.();
return { files: [..._stack[_cursor].files], affectedPaths };
}
// Returns { files, affectedPaths } from the entry being redone
export function redo() {
if (!canRedo()) return null;
++_cursor;
_onUpdate?.();
return { files: [..._stack[_cursor].files], affectedPaths: _stack[_cursor].affectedPaths };
}
export function canUndo() { return _cursor > 0; }
export function canRedo() { return _cursor < _stack.length - 1; }
export function reset() {
_stack = [];
_cursor = -1;
_onUpdate?.();
}