/**
 * Stripe Integration for LandveX Operations
 * 
 * Handles:
 * - Payment method setup (card, autogiro)
 * - Subscription billing
 * - Invoice generation
 * - Webhook handling
 */

import https from 'https';

const STRIPE_API_KEY = process.env.STRIPE_SECRET_KEY;
const STRIPE_WEBHOOK_SECRET = process.env.STRIPE_WEBHOOK_SECRET;

function stripeRequest(method, path, data = null) {
  return new Promise((resolve, reject) => {
    if (!STRIPE_API_KEY) {
      reject(new Error('Stripe not configured'));
      return;
    }

    const options = {
      hostname: 'api.stripe.com',
      port: 443,
      path: `/v1${path}`,
      method,
      headers: {
        'Authorization': `Bearer ${STRIPE_API_KEY}`,
        'Content-Type': 'application/x-www-form-urlencoded',
      },
    };

    const req = https.request(options, (res) => {
      let body = '';
      res.on('data', chunk => body += chunk);
      res.on('end', () => {
        try {
          const json = JSON.parse(body);
          if (json.error) reject(json.error);
          else resolve(json);
        } catch (e) {
          resolve(body);
        }
      });
    });

    req.on('error', reject);
    
    if (data) {
      const params = new URLSearchParams(data);
      req.write(params.toString());
    }
    
    req.end();
  });
}

// Create a customer
export async function createCustomer(email, name, metadata = {}) {
  return stripeRequest('POST', '/customers', {
    email,
    name,
    ...Object.entries(metadata).reduce((acc, [k, v]) => ({ ...acc, [`metadata[${k}]`]: v }), {}),
  });
}

// Create a payment intent
export async function createPaymentIntent(amount, currency, customerId, metadata = {}) {
  return stripeRequest('POST', '/payment_intents', {
    amount: Math.round(amount * 100), // Convert to cents
    currency: currency.toLowerCase(),
    customer: customerId,
    automatic_payment_methods: { enabled: true },
    ...Object.entries(metadata).reduce((acc, [k, v]) => ({ ...acc, [`metadata[${k}]`]: v }), {}),
  });
}

// Create a subscription
export async function createSubscription(customerId, priceId, metadata = {}) {
  return stripeRequest('POST', '/subscriptions', {
    customer: customerId,
    items: [{ price: priceId }],
    payment_behavior: 'default_incomplete',
    expand: ['latest_invoice.payment_intent'],
    ...Object.entries(metadata).reduce((acc, [k, v]) => ({ ...acc, [`metadata[${k}]`]: v }), {}),
  });
}

// Create a setup intent for saving payment methods
export async function createSetupIntent(customerId) {
  return stripeRequest('POST', '/setup_intents', {
    customer: customerId,
    usage: 'off_session',
  });
}

// List payment methods for a customer
export async function listPaymentMethods(customerId, type = 'card') {
  return stripeRequest('GET', `/customers/${customerId}/payment_methods?type=${type}`);
}

// Create invoice
export async function createInvoice(customerId, autoAdvance = true) {
  return stripeRequest('POST', '/invoices', {
    customer: customerId,
    auto_advance: autoAdvance,
  });
}

// Add invoice item
export async function createInvoiceItem(customerId, amount, currency, description) {
  return stripeRequest('POST', '/invoiceitems', {
    customer: customerId,
    amount: Math.round(amount * 100),
    currency: currency.toLowerCase(),
    description,
  });
}

// Finalize and send invoice
export async function finalizeInvoice(invoiceId) {
  return stripeRequest('POST', `/invoices/${invoiceId}/finalize`);
}

// Verify webhook signature
export function verifyWebhookSignature(payload, signature) {
  // In production, use Stripe's official library
  // This is a simplified version
  if (!STRIPE_WEBHOOK_SECRET) {
    return { valid: false, error: 'Webhook secret not configured' };
  }
  
  // For now, accept all webhooks in development
  if (process.env.NODE_ENV === 'development') {
    return { valid: true };
  }
  
  return { valid: false, error: 'Webhook verification not implemented' };
}

// Handle webhook events
export async function handleWebhookEvent(event) {
  switch (event.type) {
    case 'payment_intent.succeeded':
      console.log('Payment succeeded:', event.data.object.id);
      return { status: 'success', paymentIntent: event.data.object.id };
      
    case 'payment_intent.payment_failed':
      console.log('Payment failed:', event.data.object.id);
      return { status: 'failed', paymentIntent: event.data.object.id, error: event.data.object.last_payment_error };
      
    case 'invoice.paid':
      console.log('Invoice paid:', event.data.object.id);
      return { status: 'paid', invoice: event.data.object.id };
      
    case 'invoice.payment_failed':
      console.log('Invoice payment failed:', event.data.object.id);
      return { status: 'failed', invoice: event.data.object.id };
      
    case 'customer.subscription.created':
      console.log('Subscription created:', event.data.object.id);
      return { status: 'created', subscription: event.data.object.id };
      
    case 'customer.subscription.deleted':
      console.log('Subscription cancelled:', event.data.object.id);
      return { status: 'cancelled', subscription: event.data.object.id };
      
    default:
      console.log('Unhandled event:', event.type);
      return { status: 'unhandled', type: event.type };
  }
}

console.log('Stripe module loaded (API key:', STRIPE_API_KEY ? 'configured' : 'NOT CONFIGURED', ')');