function checkServiceWorkerSupport() {
    if (!"serviceWorker" in navigator || !"PushManager" in window)
        throw new Error("Your browser does not have Service Worker support")
}

async function unregisterPush() {
    checkServiceWorkerSupport();

    const registration = await navigator.serviceWorker.getRegistration();
    if (!registration) return;

    const subscription = await reg.pushManager.getSubscription();
    if (!subscription) return;

    await subscription.unsubscribe();
}

async function registerPush(publicKey) {
    checkServiceWorkerSupport();

    const registration = await navigator.serviceWorker.register("/assets/custom/serviceWorker.js");
    console.log("Service Worker registered");

    let subscription = await registration.pushManager.getSubscription();

    if (!subscription) {
        const applicationServerKey = urlBase64ToUint8Array(publicKey);
        subscription = await registration.pushManager.subscribe({
            userVisibleOnly: true,
            applicationServerKey
        });
        console.log("Push subscription obtained");
    }

    const response = await fetch(`${window.GLOBAL_ENV.API_ENDPOINT}/v9/users/@me/devices`, {
        method: "POST",
        headers: {
            "Content-Type": "application/json",
            "Authorization": localStorage.token
        },
        body: JSON.stringify({
            provider: "webpush",
            webpush_subscription: subscription
        })
    });

    if (response.ok) {
        console.log("Device registered successfully");
    } else {
        const text = await response.text();
        throw new Error("Failed to register: ", text)
    }
}

function urlBase64ToUint8Array(base64String) {
    const padding = "=".repeat((4 - (base64String.length % 4)) % 4);
    const base64 = (base64String + padding)
        .replace(/\-/g, "+")
        .replace(/_/g, "/");

    const rawData = atob(base64);
    const outputArray = new Uint8Array(rawData.length);

    for (let i = 0; i < rawData.length; i++) {
        outputArray[i] = rawData.charCodeAt(i);
    }

    return outputArray;
}