import { NextRequest } from "next/server";
import type Stripe from "stripe";
import { stripe } from "@/lib/billing/stripe";
import { handleStripeEvent } from "@/lib/billing/webhooks/stripe";
import { alreadyProcessed, logWebhook } from "@/lib/billing/webhook-log";

export const dynamic = "force-dynamic";

export async function POST(req: NextRequest) {
  const secret = process.env.STRIPE_WEBHOOK_SECRET;
  const signature = req.headers.get("stripe-signature");
  if (!secret || !signature) return new Response("Webhook not configured", { status: 400 });

  const body = await req.text();
  let event: Stripe.Event;
  try {
    event = stripe().webhooks.constructEvent(body, signature, secret);
  } catch (err) {
    console.error("[stripe webhook] signature verification failed", err);
    return new Response("Invalid signature", { status: 400 });
  }

  // Idempotency: skip events we've already processed (Stripe retries deliveries).
  if (await alreadyProcessed(event.id)) return new Response("ok (duplicate)");

  try {
    await handleStripeEvent(event);
    await logWebhook("stripe", event.id, event.type, "processed");
  } catch (err) {
    console.error("[stripe webhook] handler error", err);
    await logWebhook("stripe", event.id, event.type, "failed", err instanceof Error ? err.message : String(err));
    return new Response("Handler error", { status: 500 });
  }
  return new Response("ok");
}