// /api/create-checkout-session.js
import Stripe from 'stripe';

export default async function handler(req, res) {
  if (req.method !== 'POST') return res.status(405).end();

  try {
    if (!process.env.STRIPE_SECRET_KEY) {
      return res.status(500).json({ error: 'Missing STRIPE_SECRET_KEY' });
    }
    if (!process.env.STRIPE_PRICE_ID) {
      return res.status(500).json({ error: 'Missing STRIPE_PRICE_ID' });
    }

    const stripe = new Stripe(process.env.STRIPE_SECRET_KEY, {
      apiVersion: '2024-06-20',
    });

    const {
      promo = 'JUNGLE',
      email,
      success_url = 'https://hrkey.xyz/success?session_id={CHECKOUT_SESSION_ID}',
      cancel_url = 'https://hrkey.xyz/cancel',
    } = req.body || {};

    // (Opcional) Validaciones mínimas
    if (email && typeof email !== 'string') {
      return res.status(400).json({ error: 'Invalid email' });
    }

    // 1) Buscar promotion code activo (JUNGLE)
    let promotion_code_id = null;
    try {
      const promos = await stripe.promotionCodes.list({
        code: String(promo).toUpperCase(),
        active: true,
        limit: 1,
      });
      promotion_code_id = promos.data[0]?.id || null;
    } catch (_) {
      // si falla, seguimos sin promotion_code
      promotion_code_id = null;
    }

    // 2) Crear la sesión de Checkout (suscripción anual)
    const session = await stripe.checkout.sessions.create({
      mode: 'subscription',
      payment_method_collection: 'always', // forzá tarjeta aunque total hoy sea $0
      customer_creation: 'always',
      customer_email: email || undefined,

      line_items: [
        {
          price: process.env.STRIPE_PRICE_ID, // tu price anual PRO
          quantity: 1,
        },
      ],

      // Aplica el Promotion Code (JUNGLE = 100% off por 12 meses)
      discounts: promotion_code_id ? [{ promotion_code: promotion_code_id }] : [],
      allow_promotion_codes: true,

      // URLs de retorno
      success_url,
      cancel_url,

      // (Opcional) metadata útil para tu sistema
      metadata: {
        source: 'hrkey_checkout_ready',
        promo: String(promo || '').toUpperCase(),
      },
    });

    return res.status(200).json({ url: session.url });
  } catch (err) {
    console.error('[create-checkout-session] error:', err);
    return res.status(500).json({ error: 'Failed to create checkout session' });
  }
}