import { type NextRequest, NextResponse } from "next/server"
import Stripe from "stripe"

export async function POST(request: NextRequest) {
  try {
    const stripeSecretKey = process.env.STRIPE_SECRET_KEY
    if (!stripeSecretKey) {
      return NextResponse.json({ error: "Stripe not configured" }, { status: 500 })
    }

    const stripe = new Stripe(stripeSecretKey, {
      apiVersion: "2024-12-18.acacia",
    })
    const formData = await request.formData()
    const paymentMethod = formData.get("paymentMethod") as string
    const registrationDataStr = formData.get("registrationData") as string

    // Parse registration data
    const registrationData = registrationDataStr ? JSON.parse(registrationDataStr) : null

    // Configure payment method types based on selection
    let paymentMethodTypes: Stripe.Checkout.SessionCreateParams.PaymentMethodType[] = ["card"]

    if (paymentMethod === "sepa_debit") {
      paymentMethodTypes = ["sepa_debit"]
    } else if (paymentMethod === "crypto") {
      paymentMethodTypes = ["customer_balance"]
    }

    const session = await stripe.checkout.sessions.create({
      payment_method_types: paymentMethodTypes,
      line_items: [
        {
          price_data: {
            currency: "eur",
            product_data: {
              name: "Crypto Commons Gathering 2026",
              description: "Full event access including all sessions and infrastructure",
              images: ["https://ccg2025.vercel.app/og-image.png"],
            },
            unit_amount: 20000, // €200
          },
          quantity: 1,
          adjustable_quantity: {
            enabled: true,
            minimum: 1,
            maximum: 5,
          },
        },
      ],
      mode: "payment",
      success_url: `${request.nextUrl.origin}/success?session_id={CHECKOUT_SESSION_ID}`,
      cancel_url: `${request.nextUrl.origin}/register`,
      metadata: registrationData
        ? {
            name: registrationData.name,
            contact: registrationData.contact,
            contributions: registrationData.contributions.substring(0, 500), // Stripe has length limits
            expectations: registrationData.expectations.substring(0, 500),
            howHeard: registrationData.howHeard || "",
            dietary:
              registrationData.dietary.join(", ") +
              (registrationData.dietaryOther ? `, ${registrationData.dietaryOther}` : ""),
            crewConsent: registrationData.crewConsent,
          }
        : {},
      // For stablecoin payments
      ...(paymentMethod === "crypto" && {
        payment_method_options: {
          customer_balance: {
            funding_type: "crypto",
            bank_transfer: {
              type: "crypto",
            },
          },
        },
      }),
      allow_promotion_codes: true,
      billing_address_collection: "required",
      phone_number_collection: {
        enabled: true,
      },
    })

    return NextResponse.redirect(session.url!)
  } catch (err) {
    console.error("[v0] Error creating checkout session:", err)
    return NextResponse.json({ error: "Error creating checkout session" }, { status: 500 })
  }
}