Vue Track changes in textarea

<!DOCTYPE html>
<html>
<head>
    <script src="https://unpkg.com/vue@3/dist/vue.global.js"></script>
</head>
<body>
    <h3>Vue track changes in textarea</h3>
    <div id="app">
        <textarea v-model="currentValue" @input="onInput"></textarea>
        <button @click="undo">Undo</button>
        <button @click="redo">Redo</button>
    </div>
    <script type="module">
        const app = Vue.createApp({
            data() {
                return {
                    currentValue: '',
                    history: [],
                    future: []
                }
            },
            methods: {
                onInput(event) {
                    const newValue = event.target.value;
                    this.future = [];
                    this.history.push(newValue);
                },
                undo() {
                    if (this.history.length > 0) {
                        const previousValue = this.history.pop();
                        this.future.push(this.currentValue);
                        this.currentValue = previousValue;
                    }
                },
                redo() {
                    if (this.future.length > 0) {
                        const nextValue = this.future.pop();
                        this.history.push(this.currentValue);
                        this.currentValue = nextValue;
                    }
                }
            }
        });app.mount('#app');
    </script>
    <style scoped>
        textarea {
            width: 100%;
            height: 200px;
            padding: 10px;
            font-size: 16px;
            border: 1px solid #ccc;
        }

button {
            padding: 10px 20px;
            font-size: 16px;
            background-color: #007bff;
            color: #fff;
            border: none;
            border-radius: 5px;
            cursor: pointer;
            margin-right: 10px;
        }

button:hover {
            background-color: #0062cc;
        }

button:disabled {
            background-color: #ccc;
            cursor: default;
        }
    </style>
</body>
</html>