feat: add customer cart with expiry, shipping addresses with USPS validation, and multi-item PayPal checkout

frontend/src/cart/cartApi.ts

@@ -0,0 +1,97 @@
+export interface CartItem {
+  item_id: number;
+  name: string;
+  price_cents: number;
+  status: string;
+  added_at: string;
+  expires_at: string;
+  images: { id: number; image_path: string }[];
+}
+
+export interface ShippingAddress {
+  id: number;
+  full_name: string;
+  address_line1: string;
+  address_line2: string | null;
+  city: string;
+  state: string;
+  postal_code: string;
+  country: string;
+  is_default: boolean;
+  usps_validated: boolean;
+}
+
+async function handle<T>(res: Response): Promise<T> {
+  if (!res.ok) {
+    const data = await res.json().catch(() => ({}));
+    throw new Error(data.error || 'Request failed');
+  }
+  return res.json();
+}
+
+export function fetchCart(): Promise<{ items: CartItem[] }> {
+  return fetch('/api/cart').then(res => handle(res));
+}
+
+export function addToCart(itemId: number): Promise<{ itemId: number; expiresAt: string }> {
+  return fetch(`/api/cart/items/${itemId}`, { method: 'POST' }).then(res => handle(res));
+}
+
+export function removeFromCart(itemId: number): Promise<void> {
+  return fetch(`/api/cart/items/${itemId}`, { method: 'DELETE' }).then(() => undefined);
+}
+
+export function fetchAddresses(): Promise<ShippingAddress[]> {
+  return fetch('/api/customers/me/addresses').then(res => handle(res));
+}
+
+export interface AddressInput {
+  fullName: string;
+  addressLine1: string;
+  addressLine2?: string;
+  city: string;
+  state: string;
+  postalCode: string;
+  country?: string;
+  isDefault?: boolean;
+}
+
+export function createAddress(input: AddressInput): Promise<{ address: ShippingAddress; uspsCheck: { validated: boolean; deliverable: boolean | null; reason?: string }; uspsConfigured: boolean }> {
+  return fetch('/api/customers/me/addresses', {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify(input)
+  }).then(res => handle(res));
+}
+
+export function deleteAddress(id: number): Promise<void> {
+  return fetch(`/api/customers/me/addresses/${id}`, { method: 'DELETE' }).then(() => undefined);
+}
+
+export function setDefaultAddress(id: number): Promise<ShippingAddress> {
+  return fetch(`/api/customers/me/addresses/${id}/set-default`, { method: 'POST' }).then(res => handle(res));
+}
+
+export function createCartPaypalOrder(shippingAddressId: number): Promise<{ orderID: string }> {
+  return fetch('/api/checkout/cart/paypal/create', {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({ shippingAddressId })
+  }).then(res => handle(res));
+}
+
+export function captureCartPaypalOrder(orderID: string): Promise<void> {
+  return fetch('/api/checkout/cart/paypal/capture', {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({ orderID })
+  }).then(res => handle(res));
+}
+
+export function demoCartPurchase(shippingAddressId: number): Promise<void> {
+  return fetch('/api/checkout/cart/demo/purchase', {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({ shippingAddressId })
+  }).then(res => handle(res));
+}