Initial working state: CL3.5 complete (Plesk sync + suspend/unsuspend)

app/api/stripe/checkout/route.ts

@@ -0,0 +1,69 @@
+import { NextResponse } from "next/server";
+
+import { assertAgencyAdmin, getRouteAgencyContextOrThrow } from "@/lib/agency";
+import { env } from "@/lib/env";
+import { getStripeClient } from "@/lib/stripe";
+import { createSupabaseRouteClient } from "@/lib/supabase/route";
+
+export async function POST() {
+  try {
+    const context = await getRouteAgencyContextOrThrow();
+    assertAgencyAdmin(context);
+
+    if (!env.stripePriceId) {
+      throw new Error("STRIPE_PRICE_ID is not configured");
+    }
+
+    const stripe = getStripeClient();
+    const supabase = createSupabaseRouteClient();
+
+    const { data: billing, error: billingError } = await supabase
+      .from("billing_accounts")
+      .select("id, stripe_customer_id")
+      .eq("agency_id", context.agencyId)
+      .maybeSingle();
+
+    if (billingError) throw billingError;
+
+    let customerId = billing?.stripe_customer_id ?? null;
+
+    if (!customerId) {
+      const customer = await stripe.customers.create({
+        metadata: {
+          agency_id: context.agencyId,
+        },
+      });
+
+      customerId = customer.id;
+
+      const upsertPayload = {
+        agency_id: context.agencyId,
+        stripe_customer_id: customerId,
+      };
+
+      if (billing?.id) {
+        await supabase.from("billing_accounts").update(upsertPayload).eq("id", billing.id);
+      } else {
+        await supabase.from("billing_accounts").insert(upsertPayload);
+      }
+    }
+
+    const session = await stripe.checkout.sessions.create({
+      mode: "subscription",
+      customer: customerId,
+      line_items: [{ price: env.stripePriceId, quantity: 1 }],
+      success_url: `${env.appUrl}/dashboard?checkout=success`,
+      cancel_url: `${env.appUrl}/dashboard?checkout=cancelled`,
+      metadata: {
+        agency_id: context.agencyId,
+      },
+    });
+
+    return NextResponse.json({ url: session.url });
+  } catch (error) {
+    return NextResponse.json(
+      { error: error instanceof Error ? error.message : "Failed to create checkout session" },
+      { status: 400 },
+    );
+  }
+}