Initial OSS scaffold from Songs2VID (pre-strip)

app/api/account/billing-portal/route.ts

@@ -0,0 +1,64 @@
+import { NextRequest, NextResponse } from "next/server";
+import { prisma } from "@/lib/db";
+import { getSessionUser } from "@/lib/session";
+import { getStripe, isBillingDevMock, isStripeConfigured } from "@/lib/stripe";
+
+/**
+ * Stripe Customer Portal  update payment method, view invoices, cancel (per Dashboard config).
+ * @see https://docs.stripe.com/customer-management/integrate-customer-portal
+ */
+export async function POST(req: NextRequest) {
+  const user = await getSessionUser();
+  if (!user) {
+    return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
+  }
+
+  if (isBillingDevMock()) {
+    return NextResponse.json(
+      { error: "Billing portal is unavailable in mock mode." },
+      { status: 503 },
+    );
+  }
+
+  if (!isStripeConfigured()) {
+    return NextResponse.json(
+      { error: "Payments are not configured yet. Set STRIPE_SECRET_KEY." },
+      { status: 503 },
+    );
+  }
+
+  const dbUser = await prisma.user.findUniqueOrThrow({
+    where: { id: user.id },
+    select: { stripeCustomerId: true },
+  });
+
+  if (!dbUser.stripeCustomerId) {
+    return NextResponse.json(
+      { error: "No Stripe customer on this account. Complete a checkout first." },
+      { status: 400 },
+    );
+  }
+
+  const origin = process.env.NEXTAUTH_URL || req.nextUrl.origin;
+  const stripe = getStripe();
+
+  try {
+    const session = await stripe.billingPortal.sessions.create({
+      customer: dbUser.stripeCustomerId,
+      return_url: `${origin}/dashboard/settings`,
+    });
+    return NextResponse.json({ url: session.url });
+  } catch (err) {
+    const message = err instanceof Error ? err.message : "Could not open billing portal";
+    console.error("[stripe] billing portal failed", err);
+    return NextResponse.json(
+      {
+        error:
+          message.includes("No configuration") || message.includes("portal")
+            ? "Billing portal is not configured in Stripe Dashboard yet. Enable it under Settings → Billing → Customer portal."
+            : message,
+      },
+      { status: 502 },
+    );
+  }
+}