fix(api): keep premium through cancellation and refund pix exactly (#1995)

fluxer_api/src/api/worker/tasks/ProcessPremiumStateReconciliationQueue.ts

@@ -128,19 +128,39 @@ function chooseEffectiveSubscription(user: User, subscriptions: Array<Stripe.Sub
 	return sorted[0]!;
 }
 
+function trackMostRecentTerminalSubscription(
+	current: Stripe.Subscription | null,
+	candidate: Stripe.Subscription,
+): Stripe.Subscription | null {
+	if (!candidate.ended_at) {
+		return current;
+	}
+	if (!current || (current.ended_at ?? 0) < candidate.ended_at) {
+		return candidate;
+	}
+	return current;
+}
+
 async function getEffectiveActiveStripeSubscription(
 	stripe: Stripe,
 	user: User,
 ): Promise<{
 	subscription: Stripe.Subscription | null;
 	activeCount: number;
+	mostRecentTerminalSubscription: Stripe.Subscription | null;
 }> {
 	const subscriptionsById = new Map<string, Stripe.Subscription>();
+	let mostRecentTerminalSubscription: Stripe.Subscription | null = null;
 	if (user.stripeSubscriptionId) {
 		try {
 			const subscription = await stripe.subscriptions.retrieve(user.stripeSubscriptionId);
 			if (canProvisionPremiumFromSubscriptionStatus(subscription.status)) {
 				subscriptionsById.set(subscription.id, subscription);
+			} else {
+				mostRecentTerminalSubscription = trackMostRecentTerminalSubscription(
+					mostRecentTerminalSubscription,
+					subscription,
+				);
 			}
 		} catch (error) {
 			Logger.warn(
@@ -162,6 +182,10 @@ async function getEffectiveActiveStripeSubscription(
 			});
 			for (const subscription of subscriptions.data) {
 				if (!canProvisionPremiumFromSubscriptionStatus(subscription.status)) {
+					mostRecentTerminalSubscription = trackMostRecentTerminalSubscription(
+						mostRecentTerminalSubscription,
+						subscription,
+					);
 					continue;
 				}
 				subscriptionsById.set(subscription.id, subscription);
@@ -182,11 +206,13 @@ async function getEffectiveActiveStripeSubscription(
 		return {
 			subscription: null,
 			activeCount: 0,
+			mostRecentTerminalSubscription,
 		};
 	}
 	return {
 		subscription: chooseEffectiveSubscription(user, activeSubscriptions),
 		activeCount: activeSubscriptions.length,
+		mostRecentTerminalSubscription,
 	};
 }
 
@@ -203,15 +229,29 @@ async function reconcileUserPremiumStateFromStripe(params: {userId: UserID; stri
 	if (!user.stripeSubscriptionId && !user.stripeCustomerId) {
 		return {status: 'skipped', patchedFields: []};
 	}
-	const {subscription, activeCount} = await getEffectiveActiveStripeSubscription(stripe, user);
+	const {subscription, activeCount, mostRecentTerminalSubscription} = await getEffectiveActiveStripeSubscription(
+		stripe,
+		user,
+	);
 	if (!subscription) {
 		const hasStalePremium = user.premiumType === UserPremiumTypes.SUBSCRIPTION;
 		const hasNonStripePremium = Config.instance.selfHosted || (user.premiumFlags & PremiumFlags.ENABLED_OVERRIDE) !== 0;
 		if (hasStalePremium && !hasNonStripePremium) {
-			const effectivePremiumUntil = getEffectivePremiumUntil(user);
+			const patch: Partial<UserRow> = {};
+			let effectivePremiumUntil = getEffectivePremiumUntil(user);
+			if (mostRecentTerminalSubscription?.ended_at && user.premiumUntil) {
+				const subscriptionEndedAt = new Date(mostRecentTerminalSubscription.ended_at * 1000);
+				if (subscriptionEndedAt.getTime() < user.premiumUntil.getTime()) {
+					patch.premium_until = subscriptionEndedAt;
+					patch.premium_grace_ends_at = subscriptionEndedAt;
+					effectivePremiumUntil = getEffectivePremiumUntil({
+						premiumUntil: subscriptionEndedAt,
+						premiumGiftExtensionEndsAt: user.premiumGiftExtensionEndsAt,
+					});
+				}
+			}
 			const hasFutureLocalEntitlement = effectivePremiumUntil != null && Date.now() <= effectivePremiumUntil.getTime();
 			if (hasFutureLocalEntitlement) {
-				const patch: Partial<UserRow> = {};
 				if (user.premiumWillCancel !== true) {
 					patch.premium_will_cancel = true;
 				}