Files

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TypeScript

const authChannelName = "makers3d-auth";
const authTabIdKey = "makers3d-auth-tab";
export type AuthEventType = "login" | "logout";
function getTabId() {
let tabId = window.sessionStorage.getItem(authTabIdKey);
if (!tabId) {
tabId = crypto.randomUUID();
window.sessionStorage.setItem(authTabIdKey, tabId);
}
return tabId;
}
export function notifyAuthChanged(type: AuthEventType) {
if (typeof window === "undefined") {
return;
}
const payload = JSON.stringify({ type, source: getTabId(), at: Date.now() });
if ("BroadcastChannel" in window) {
const channel = new BroadcastChannel(authChannelName);
channel.postMessage(payload);
channel.close();
}
window.localStorage.setItem(authChannelName, payload);
}
export function listenAuthChanged(callback: (type: AuthEventType) => void) {
if (typeof window === "undefined") {
return () => {};
}
function handlePayload(payload: unknown) {
if (typeof payload !== "string") {
return;
}
try {
const event = JSON.parse(payload) as { type?: AuthEventType; source?: string };
if (event.source === getTabId()) {
return;
}
if (event.type === "login" || event.type === "logout") {
callback(event.type);
}
} catch {
// Ignore malformed cross-tab payloads.
}
}
const channel = "BroadcastChannel" in window ? new BroadcastChannel(authChannelName) : null;
channel?.addEventListener("message", (event) => handlePayload(event.data));
const storageListener = (event: StorageEvent) => {
if (event.key === authChannelName) {
handlePayload(event.newValue);
}
};
window.addEventListener("storage", storageListener);
return () => {
channel?.close();
window.removeEventListener("storage", storageListener);
};
}