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import { api } from './api.js';
import { getUser, onAuthChange } from './auth.js';
// How many of your friends are around right now, for the count beside the
// Friends control.
//
// Shared and cached rather than fetched per control: the rail is rebuilt on
// every screen change, and without this each navigation fired a fresh
// request.
const REFRESH_MS = 30000;
let cache = { friends: 0, friendsOnline: 0 };
const listeners = new Set();
let timer = null;
let inFlight = false;
async function refresh() {
if (inFlight) return;
inFlight = true;
try {
// Friends only exist for a signed-in user; asking while signed out is
// a guaranteed 401, so skip it rather than log noise on every poll.
if (!getUser()) {
cache = { friends: 0, friendsOnline: 0 };
} else {
const list = await api.get('/api/friends').catch(() => null);
if (list) {
const friends = list.friends || [];
cache = { friends: friends.length, friendsOnline: friends.filter(f => f.online).length };
}
}
for (const fn of listeners) fn(cache);
} finally {
inFlight = false;
}
}
export function getCounts() {
return cache;
}
// Returns an unsubscribe function. Polling runs only while something is
// listening, so a screen with no badges costs nothing.
export function onCountsChange(fn) {
listeners.add(fn);
if (!timer) {
refresh();
timer = setInterval(refresh, REFRESH_MS);
}
return () => {
listeners.delete(fn);
if (listeners.size === 0 && timer) {
clearInterval(timer);
timer = null;
}
};
}
// Signing in or out changes the friend count immediately - waiting up to the
// full poll interval would leave a stale badge behind.
onAuthChange(() => {
if (listeners.size > 0) refresh();
});
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