Billing Configuration

STRIPE_SECRET_KEY=sk_test_51Abc123...
STRIPE_WEBHOOK_SECRET=whsec_xyz789...

import Stripe from 'stripe';

const stripe = new Stripe(process.env.STRIPE_SECRET_KEY, {
  apiVersion: '2023-08-16',
  typescript: true,
});

export const createCheckout = async ({
  priceId,
  mode,
  successUrl,
  cancelUrl,
  clientReferenceId,
  user,
  couponId,
}: CreateCheckoutParams): Promise<string> => {
  const stripe = new Stripe(process.env.STRIPE_SECRET_KEY, {
    apiVersion: '2023-08-16',
    typescript: true,
  });

  const extraParams: any = {};

  if (user?.customerId) {
    extraParams.customer = user.customerId;
  } else {
    if (mode === 'payment') {
      extraParams.customer_creation = 'always';
      extraParams.payment_intent_data = {
        setup_future_usage: 'on_session'
      };
    }
    if (user?.email) {
      extraParams.customer_email = user.email;
    }
    extraParams.tax_id_collection = { enabled: true };
  }

  const stripeSession = await stripe.checkout.sessions.create({
    mode,
    allow_promotion_codes: true,
    client_reference_id: clientReferenceId,
    line_items: [{ price: priceId, quantity: 1 }],
    discounts: couponId ? [{ coupon: couponId }] : [],
    success_url: successUrl,
    cancel_url: cancelUrl,
    ...extraParams,
  });

  return stripeSession.url;
};

export const createCustomerPortal = async ({
  customerId,
  returnUrl,
}: CreateCustomerPortalParams): Promise<string> => {
  const stripe = new Stripe(process.env.STRIPE_SECRET_KEY, {
    apiVersion: '2023-08-16',
    typescript: true,
  });

  const portalSession = await stripe.billingPortal.sessions.create({
    customer: customerId,
    return_url: returnUrl,
  });

  return portalSession.url;
};

export async function POST(req: NextRequest) {
  const body = await req.json();

  if (!body.priceId || !body.successUrl || !body.cancelUrl || !body.mode) {
    return NextResponse.json({ error: 'Missing required fields' }, { status: 400 });
  }

  try {
    const supabase = await createClient();
    const { data: { user } } = await supabase.auth.getUser();

    const stripeSessionURL = await createCheckout({
      priceId: body.priceId,
      mode: body.mode,
      successUrl: body.successUrl,
      cancelUrl: body.cancelUrl,
      clientReferenceId: user?.id,
      user: user ? { email: user.email, customerId: null } : null,
    });

    return NextResponse.json({ url: stripeSessionURL });
  } catch (e: any) {
    return NextResponse.json({ error: e?.message }, { status: 500 });
  }
}

export async function POST(req: NextRequest) {
  const supabase = await createClient();
  const { data: { user } } = await supabase.auth.getUser();

  if (!user) {
    return NextResponse.json({ error: 'Not signed in' }, { status: 401 });
  }

  const body = await req.json();
  if (!body.returnUrl) {
    return NextResponse.json({ error: 'Return URL is required' }, { status: 400 });
  }

  // TODO: Look up customerId from database
  const customerId: string | null = null;

  if (!customerId) {
    return NextResponse.json(
      { error: "You don't have a billing account yet. Make a purchase first." },
      { status: 400 }
    );
  }

  const stripePortalUrl = await createCustomerPortal({
    customerId,
    returnUrl: body.returnUrl,
  });

  return NextResponse.json({ url: stripePortalUrl });
}