feat(paystack): implement downgrade for expired canceled subscriptions and support variable billing intervals

Author: xt42io

apps/cron/src/lib/paystack.ts

@@ -41,6 +41,11 @@ interface Subscription {
   current_period_end: Date;
 }
 
+interface ExpiredCanceledSubscription {
+  id: string;
+  organization_id: string;
+}
+
 /**
  * Charge a stored authorization
  */
@@ -128,6 +133,7 @@ async function getDueSubscriptions(): Promise<Subscription[]> {
        FROM subscriptions
        WHERE payment_provider = 'paystack'
          AND status = 'active'
+         AND cancel_at_period_end = false
          AND paystack_authorization_code IS NOT NULL
          AND paystack_email IS NOT NULL
          AND current_period_end <= NOW()`,
@@ -138,6 +144,33 @@ async function getDueSubscriptions(): Promise<Subscription[]> {
   }
 }
 
+/**
+ * Downgrade Paystack subscriptions that were canceled and have reached period end.
+ *
+ * We currently model the free tier as "no subscription row", so deleting the row
+ * keeps plan enforcement consistent across the app and prevents any future charges.
+ */
+async function downgradeExpiredCanceledSubscriptions(): Promise<void> {
+  const client = await dbPool.connect();
+  try {
+    const result = await client.query<ExpiredCanceledSubscription>(
+      `DELETE FROM subscriptions
+       WHERE payment_provider = 'paystack'
+         AND cancel_at_period_end = true
+         AND current_period_end <= NOW()
+       RETURNING id, organization_id`,
+    );
+
+    if (result.rowCount) {
+      console.log(
+        `[Paystack] Downgraded ${result.rowCount} canceled subscription(s) to free plan`,
+      );
+    }
+  } finally {
+    client.release();
+  }
+}
+
 /**
  * Update subscription after successful charge
  */
@@ -200,6 +233,8 @@ export async function chargePaystackSubscriptions(): Promise<void> {
   console.log("[Paystack] Starting recurring charge job...");
 
   try {
+    await downgradeExpiredCanceledSubscriptions();
+
     const dueSubscriptions = await getDueSubscriptions();
     console.log(
       `[Paystack] Found ${dueSubscriptions.length} subscriptions due for renewal`,

apps/web/src/routes/api/checkout/paystack-verify.ts

@@ -72,6 +72,7 @@ export const Route = createFileRoute("/api/checkout/paystack-verify")({
           const metadata = verification.data.metadata as {
             organizationId?: string;
             plan?: string;
+            interval?: "month" | "year";
             userId?: string;
           };
 
@@ -82,7 +83,7 @@ export const Route = createFileRoute("/api/checkout/paystack-verify")({
             );
           }
 
-          const { organizationId, plan, userId } = metadata;
+          const { organizationId, plan, interval = "month", userId } = metadata;
 
           // Verify that the transaction was initiated by the current user
           if (userId !== session.user.id) {
@@ -116,9 +117,13 @@ export const Route = createFileRoute("/api/checkout/paystack-verify")({
           const customerEmail = verification.data.customer.email;
           const customerCode = verification.data.customer.customer_code;
 
-          // Calculate next billing date (1 month from now)
+          // Calculate next billing date based on the checkout interval
           const currentPeriodEnd = new Date();
-          currentPeriodEnd.setMonth(currentPeriodEnd.getMonth() + 1);
+          if (interval === "year") {
+            currentPeriodEnd.setFullYear(currentPeriodEnd.getFullYear() + 1);
+          } else {
+            currentPeriodEnd.setMonth(currentPeriodEnd.getMonth() + 1);
+          }
 
           // Check if subscription exists
           const existingSubscription = await db
@@ -138,6 +143,7 @@ export const Route = createFileRoute("/api/checkout/paystack-verify")({
                 paystackCustomerCode: customerCode,
                 paystackAuthorizationCode: authorization.authorization_code,
                 paystackEmail: customerEmail,
+                billingInterval: interval,
                 currentPeriodEnd,
                 cancelAtPeriodEnd: false,
                 canceledAt: null,
@@ -155,6 +161,7 @@ export const Route = createFileRoute("/api/checkout/paystack-verify")({
               paystackCustomerCode: customerCode,
               paystackAuthorizationCode: authorization.authorization_code,
               paystackEmail: customerEmail,
+              billingInterval: interval,
               currentPeriodEnd,
               cancelAtPeriodEnd: false,
             });