import { loadStripe } from '@stripe/stripe-js';

// Stripe Configuration
export const STRIPE_CONFIG = {
  publishableKey: import.meta.env.VITE_STRIPE_PUBLISHABLE_KEY || '',
  apiUrl: import.meta.env.VITE_API_URL || 'http://localhost:3001',
};

// Stripe instance (lazy loaded)
let stripePromise: ReturnType<typeof loadStripe> | null = null;

export function getStripe() {
  if (!stripePromise && STRIPE_CONFIG.publishableKey) {
    stripePromise = loadStripe(STRIPE_CONFIG.publishableKey);
  }
  return stripePromise;
}

// Types
export interface OrderData {
  websiteType: string;
  style: string;
  theme: string;
  colors: {
    primary: string;
    secondary: string;
    accent: string;
  };
  customInput?: {
    referenceUrl: string;
    description: string;
  };
  contact: {
    name: string;
    email: string;
    company?: string;
    phone?: string;
  };
}

export interface CheckoutResponse {
  sessionId: string;
  url: string;
}

export interface SessionData {
  id: string;
  status: string;
  customerEmail: string;
  amountTotal: number;
  metadata: Record<string, string>;
}

/**
 * Create a Stripe Checkout Session via backend API
 */
export async function createCheckoutSession(orderData: OrderData): Promise<CheckoutResponse> {
  const response = await fetch(`${STRIPE_CONFIG.apiUrl}/api/checkout`, {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
    },
    body: JSON.stringify({ orderData }),
  });

  if (!response.ok) {
    const error = await response.json();
    throw new Error(error.details || error.error || 'Failed to create checkout session');
  }

  return response.json();
}

/**
 * Redirect to Stripe Checkout
 */
export async function redirectToCheckout(orderData: OrderData): Promise<void> {
  const { url } = await createCheckoutSession(orderData);
  
  if (url) {
    window.location.href = url;
  } else {
    throw new Error('No checkout URL returned');
  }
}

/**
 * Verify a checkout session (for success page)
 */
export async function verifySession(sessionId: string): Promise<SessionData> {
  const response = await fetch(`${STRIPE_CONFIG.apiUrl}/api/session/${sessionId}`);
  
  if (!response.ok) {
    throw new Error('Session not found');
  }
  
  return response.json();
}