Konami Code as a Vue3 composable

App.vue

<script setup>
import konamiCode from "../composables/konamiCode";
import { onMounted } from "vue";

const { startKonamiCodeListener } = konamiCode();

onMounted(() => {
    startKonamiCodeListener(() => { console.log('God Mode Activated'); });
});
</script>

konamiCode.js

export default function konamiCode() {
    const KONAMI_CODE = [
        'ArrowUp',
        'ArrowUp',
        'ArrowDown',
        'ArrowDown',
        'ArrowLeft',
        'ArrowRight',
        'ArrowLeft',
        'ArrowRight',
        'b',
        'a',
    ];
    let c = 0;

    function startKonamiCodeListener(cb) {
        window.addEventListener("keydown", (e) => {
            c = (e.key === KONAMI_CODE[c] ? c + 1 : (e.key !== 'ArrowUp' ? 0 : (c ? (KONAMI_CODE[c-1] === 'ArrowUp' ? c : 0) : 0)));
            if (c === KONAMI_CODE.length) {
                cb()
            }
        });
    }

    return {
        startKonamiCodeListener
    }
}

This is one of the few implementations I could find that take into account the possibility of hitting "up" 3 times at the beginning (which would be a valid input) without resetting a counter