fix browser notifications + make them work when browser is closed

Overlord-Server/src/server/web-push.ts

@@ -0,0 +1,66 @@
+import webpush from "web-push";
+import { existsSync, readFileSync, writeFileSync } from "fs";
+import { resolve } from "path";
+import { ensureDataDir } from "../paths";
+import { logger } from "../logger";
+
+let vapidKeys: { publicKey: string; privateKey: string } | null = null;
+
+function getVapidPath(): string {
+  return resolve(ensureDataDir(), "vapid-keys.json");
+}
+
+export function loadOrGenerateVapidKeys(): { publicKey: string; privateKey: string } {
+  if (vapidKeys) return vapidKeys;
+
+  const vapidPath = getVapidPath();
+
+  if (existsSync(vapidPath)) {
+    try {
+      const raw = readFileSync(vapidPath, "utf-8");
+      const parsed = JSON.parse(raw);
+      if (parsed.publicKey && parsed.privateKey) {
+        vapidKeys = { publicKey: parsed.publicKey, privateKey: parsed.privateKey };
+        logger.info("[web-push] loaded VAPID keys from " + vapidPath);
+        return vapidKeys;
+      }
+    } catch (err) {
+      logger.warn("[web-push] failed to read vapid-keys.json, regenerating", err);
+    }
+  }
+
+  const generated = webpush.generateVAPIDKeys();
+  vapidKeys = { publicKey: generated.publicKey, privateKey: generated.privateKey };
+
+  try {
+    writeFileSync(vapidPath, JSON.stringify(vapidKeys, null, 2));
+    logger.info("[web-push] generated and saved VAPID keys to " + vapidPath);
+  } catch (err) {
+    logger.warn("[web-push] failed to persist VAPID keys", err);
+  }
+
+  return vapidKeys;
+}
+
+export function getVapidPublicKey(): string {
+  return loadOrGenerateVapidKeys().publicKey;
+}
+
+export async function sendWebPush(
+  subscription: { endpoint: string; keys: { p256dh: string; auth: string } },
+  payload: string,
+): Promise<{ success: boolean; gone?: boolean; error?: string }> {
+  const keys = loadOrGenerateVapidKeys();
+  webpush.setVapidDetails("mailto:overlord@localhost", keys.publicKey, keys.privateKey);
+
+  try {
+    await webpush.sendNotification(subscription, payload, { TTL: 60 * 60 });
+    return { success: true };
+  } catch (err: any) {
+    const statusCode = err?.statusCode;
+    if (statusCode === 404 || statusCode === 410) {
+      return { success: false, gone: true, error: `subscription gone (${statusCode})` };
+    }
+    return { success: false, error: err?.message || String(err) };
+  }
+}