json-crdt-repo/lib/undo-redo/UndoRedoStack.js

JSON CRDT server and syncing local-first browser client

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.UndoRedoStack = void 0;
const timeout_1 = require("thingies/lib/timeout");
const timeout2 = (ms, promise) => (0, timeout_1.timeout)(ms, promise).catch(() => undefined);
class UndoRedoStack {
    constructor() {
        this.undoStack = [];
        this.redoStack = [];
        this.locked = false;
    }
    undoLength() {
        return this.undoStack.length;
    }
    redoLength() {
        return this.redoStack.length;
    }
    push(undo) {
        const redoStack = this.redoStack;
        this.redoStack = [];
        this.undoStack.push(undo);
        return redoStack;
    }
    async undo() {
        if (this.locked)
            return 0;
        this.locked = true;
        try {
            const undo = this.undoStack.pop();
            if (!undo)
                return -1;
            let redo = undo.undo();
            if (redo && typeof redo === 'object' && typeof redo.then === 'function') {
                redo = await timeout2(2000, Promise.resolve(redo));
                if (!redo)
                    return -2;
            }
            this.redoStack.push(redo);
            return 1;
        }
        finally {
            this.locked = false;
        }
    }
    async redo() {
        if (this.locked)
            return 0;
        this.locked = true;
        try {
            const redo = this.redoStack.pop();
            if (!redo)
                return -1;
            let undo = redo.redo();
            if (undo && typeof undo === 'object' && typeof undo.then === 'function') {
                undo = await timeout2(2000, Promise.resolve(undo));
                if (!undo)
                    return -2;
            }
            this.undoStack.push(undo);
            return 1;
        }
        catch {
            return -3;
        }
        finally {
            this.locked = false;
        }
    }
}
exports.UndoRedoStack = UndoRedoStack;