Add shared customer auth, cart handoff, and account dropdown.

Mirror Meshkee customer sessions onto the storefront, continue checkout on the customer dashboard, and show profile/orders/admin links under the header name.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/lib/guest-cart.ts

@@ -0,0 +1,119 @@
+import type { CartItem } from "@/lib/cart-types";
+
+/** Must match customer dashboard `GUEST_CART_STORAGE_KEY`. */
+export const MESHKEE_GUEST_CART_KEY = "meshkee-guest-cart";
+export const LEGACY_GUEST_CART_KEY = "sanihome-guest-cart";
+export const GUEST_CART_URL_PARAM = "guestCart";
+
+export type MeshkeeGuestCartItem = {
+  id: string;
+  name: string;
+  slug?: string;
+  price: number;
+  originalPrice?: number;
+  image: string | null;
+  quantity: number;
+};
+
+function cookieDomain(): string | undefined {
+  if (typeof window === "undefined") return undefined;
+  const host = window.location.hostname.toLowerCase();
+  if (host === "localhost" || host === "127.0.0.1") return undefined;
+  const parts = host.split(".").filter(Boolean);
+  if (parts.length < 2) return undefined;
+  return `.${parts.slice(-2).join(".")}`;
+}
+
+function parseItems(raw: string | null): CartItem[] {
+  if (!raw) return [];
+  try {
+    const parsed = JSON.parse(raw) as CartItem[];
+    return Array.isArray(parsed) ? parsed : [];
+  } catch {
+    return [];
+  }
+}
+
+/** Map storefront cart lines to the shared guest-cart shape (id = variant id). */
+export function toMeshkeeGuestItems(items: CartItem[]): MeshkeeGuestCartItem[] {
+  return items
+    .map((item) => {
+      const variantId = (item.storeItemVariantId || item.id || "").trim();
+      if (!variantId) return null;
+      return {
+        id: variantId,
+        name: item.name || "محصول",
+        slug: item.slug || undefined,
+        price: item.price,
+        image: item.image ?? null,
+        quantity: Math.max(1, Math.floor(item.quantity) || 1),
+      };
+    })
+    .filter((item): item is MeshkeeGuestCartItem => item != null);
+}
+
+export function encodeGuestCartForUrl(items: CartItem[]): string {
+  const payload = toMeshkeeGuestItems(items);
+  const json = JSON.stringify(payload);
+  return btoa(unescape(encodeURIComponent(json)))
+    .replace(/\+/g, "-")
+    .replace(/\//g, "_")
+    .replace(/=+$/, "");
+}
+
+function writeSharedCookie(items: MeshkeeGuestCartItem[]) {
+  if (typeof document === "undefined") return;
+  const domain = cookieDomain();
+  const maxAge = 60 * 60 * 24 * 30;
+  const encoded = encodeURIComponent(
+    JSON.stringify(
+      items.map(({ id, name, slug, price, originalPrice, quantity }) => ({
+        id,
+        name,
+        slug,
+        price,
+        originalPrice,
+        quantity,
+        image: null as string | null,
+      })),
+    ),
+  );
+  if (encoded.length > 3500) return;
+  let cookie = `${MESHKEE_GUEST_CART_KEY}=${encoded}; path=/; max-age=${maxAge}; SameSite=Lax`;
+  if (domain) cookie += `; domain=${domain}`;
+  document.cookie = cookie;
+}
+
+export function readGuestCart(): CartItem[] {
+  if (typeof window === "undefined") return [];
+  const primary = parseItems(localStorage.getItem(MESHKEE_GUEST_CART_KEY));
+  if (primary.length > 0) return primary;
+  const legacy = parseItems(localStorage.getItem(LEGACY_GUEST_CART_KEY));
+  if (legacy.length > 0) {
+    writeGuestCart(legacy);
+    return legacy;
+  }
+  return [];
+}
+
+export function writeGuestCart(items: CartItem[]) {
+  if (typeof window === "undefined") return;
+  const raw = JSON.stringify(items);
+  localStorage.setItem(MESHKEE_GUEST_CART_KEY, raw);
+  localStorage.removeItem(LEGACY_GUEST_CART_KEY);
+  try {
+    writeSharedCookie(toMeshkeeGuestItems(items));
+  } catch {
+    // ignore cookie failures
+  }
+}
+
+export function clearGuestCart() {
+  if (typeof window === "undefined") return;
+  localStorage.removeItem(MESHKEE_GUEST_CART_KEY);
+  localStorage.removeItem(LEGACY_GUEST_CART_KEY);
+  const domain = cookieDomain();
+  let cookie = `${MESHKEE_GUEST_CART_KEY}=; path=/; max-age=0; SameSite=Lax`;
+  if (domain) cookie += `; domain=${domain}`;
+  document.cookie = cookie;
+}