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);

    const supabase = createSupabaseRouteClient() as any;
    const stripe = getStripeClient();

    const { data: billing, error } = await supabase
      .from("billing_accounts")
      .select("stripe_customer_id")
      .eq("agency_id", context.agencyId)
      .maybeSingle();

    if (error) throw error;
    if (!billing?.stripe_customer_id) {
      throw new Error("No Stripe customer is linked to this agency");
    }

    const session = await stripe.billingPortal.sessions.create({
      customer: billing.stripe_customer_id,
      return_url: `${env.appUrl}/dashboard`,
    });

    return NextResponse.json({ url: session.url });
  } catch (error) {
    return NextResponse.json(
      {
        error:
          error instanceof Error
            ? error.message
            : "Failed to open billing portal",
      },
      { status: 400 },
    );
  }
}