add three day grace period

src/routes/settings/Plus.tsx

@@ -27,6 +27,7 @@ import eify from "~/utils/eify";
 import party from "~/assets/party.gif";
 import { LoadingShimmer } from "~/components/BalanceBox";
 import { useI18n } from "~/i18n/context";
+import { subscriptionValid } from "~/utils/subscriptions";
 
 function Perks(props: { alreadySubbed?: boolean }) {
     const i18n = useI18n();
@@ -114,10 +115,7 @@ function PlusCTA() {
                 );
             }
 
-            if (
-                state.subscription_timestamp &&
-                state.subscription_timestamp < Math.ceil(Date.now() / 1000)
-            ) {
+            if (!subscriptionValid(state.subscription_timestamp)) {
                 setError(
                     new Error(
                         i18n.t("settings.plus.error_expired_subscription")

src/state/megaStore.tsx

@@ -23,6 +23,7 @@ import { checkBrowserCompatibility } from "~/logic/browserCompatibility";
 import eify from "~/utils/eify";
 import { timeout } from "~/utils/timeout";
 import { ParsedParams } from "~/logic/waila";
+import { subscriptionValid } from "~/utils/subscriptions";
 
 const MegaStoreContext = createContext<MegaStore>();
 
@@ -81,13 +82,8 @@ export const Provider: ParentComponent = (props) => {
         existing_tab_detected: false,
         subscription_timestamp: undefined as number | undefined,
         get mutiny_plus(): boolean {
-            // No subscription
-            if (!state.subscription_timestamp) return false;
-
-            // Expired
-            if (state.subscription_timestamp < Math.ceil(Date.now() / 1000))
-                return false;
-            else return true;
+            // Make sure the subscription hasn't expired
+            return subscriptionValid(state.subscription_timestamp);
         },
         needs_password: false,
         load_stage: "fresh" as LoadStage,

src/utils/subscriptions.ts

@@ -0,0 +1,7 @@
+const GRACE = 60 * 60 * 24 * 3; // 3 days
+
+export function subscriptionValid(subscriptionExpiresTimestamp?: number) {
+    if (!subscriptionExpiresTimestamp) return false;
+
+    return subscriptionExpiresTimestamp + GRACE > Math.ceil(Date.now() / 1000);
+}