commerce/components/cart/modal.tsx

'use client';

import { Dialog, DialogPanel, Transition, TransitionChild } from '@headlessui/react';
import { ShoppingCartIcon } from '@heroicons/react/24/outline';
import Price from 'components/price';
import type { Cart } from 'lib/shopify/types';
import { Fragment, useEffect, useRef, useState } from 'react';
import CloseCart from './close-cart';
import LineItem from './line-item';
import OpenCart from './open-cart';

export default function CartModal({ cart }: { cart: Cart | undefined }) {
  const [isOpen, setIsOpen] = useState(false);
  const quantityRef = useRef(cart?.totalQuantity);
  const openCart = () => setIsOpen(true);
  const closeCart = () => setIsOpen(false);

  useEffect(() => {
    // Open cart modal when quantity changes.
    if (cart?.totalQuantity !== quantityRef.current) {
      // But only if it's not already open (quantity also changes when editing items in cart).
      if (!isOpen) {
        setIsOpen(true);
      }

      // Always update the quantity reference
      quantityRef.current = cart?.totalQuantity;
    }
  }, [isOpen, cart?.totalQuantity, quantityRef]);

  return (
    <>
      <button aria-label="Open cart" onClick={openCart}>
        <OpenCart quantity={cart?.totalQuantity} />
      </button>
      <Transition show={isOpen} as={Fragment}>
        <Dialog onClose={closeCart} className="relative z-50">
          <TransitionChild
            as={Fragment}
            enter="transition-all ease-in-out duration-300"
            enterFrom="opacity-0 backdrop-blur-none"
            enterTo="opacity-100 backdrop-blur-[.5px]"
            leave="transition-all ease-in-out duration-200"
            leaveFrom="opacity-100 backdrop-blur-[.5px]"
            leaveTo="opacity-0 backdrop-blur-none"
          >
            <div className="fixed inset-0 bg-black/30" aria-hidden="true" />
          </TransitionChild>
          <TransitionChild
            as={Fragment}
            enter="transition-all ease-in-out duration-300"
            enterFrom="translate-x-full"
            enterTo="translate-x-0"
            leave="transition-all ease-in-out duration-200"
            leaveFrom="translate-x-0"
            leaveTo="translate-x-full"
          >
            <DialogPanel className="fixed bottom-0 right-0 top-0 flex h-full w-full flex-col border-l border-neutral-200 bg-white/80 p-6 text-black backdrop-blur-xl dark:border-neutral-700 dark:bg-black/80 dark:text-white md:w-[390px]">
              <div className="flex items-center justify-between">
                <p className="text-lg font-semibold">My Cart</p>

                <button aria-label="Close cart" onClick={closeCart}>
                  <CloseCart />
                </button>
              </div>

              {!cart || cart.lines.length === 0 ? (
                <div className="mt-20 flex w-full flex-col items-center justify-center overflow-hidden">
                  <ShoppingCartIcon className="h-16" />
                  <p className="mt-6 text-center text-2xl font-bold">Your cart is empty.</p>
                </div>
              ) : (
                <div className="flex h-full flex-col justify-between overflow-hidden p-1">
                  <ul className="flex-grow overflow-auto py-4">
                    {cart.lines.map((item) => {
                      return <LineItem item={item} closeCart={closeCart} key={item.id} />;
                    })}
                  </ul>
                  <div className="py-4 text-sm text-neutral-500 dark:text-neutral-400">
                    <div className="mb-3 flex items-center justify-between border-b border-neutral-200 pb-1 dark:border-neutral-700">
                      <p>Taxes</p>
                      <Price
                        className="text-right text-base text-black dark:text-white"
                        amount={cart.cost.totalTaxAmount.amount}
                        currencyCode={cart.cost.totalTaxAmount.currencyCode}
                      />
                    </div>
                    <div className="mb-3 flex items-center justify-between border-b border-neutral-200 pb-1 pt-1 dark:border-neutral-700">
                      <p>Shipping</p>
                      <p className="text-right">Calculated at checkout</p>
                    </div>
                    <div className="mb-3 flex items-center justify-between border-b border-neutral-200 pb-1 pt-1 dark:border-neutral-700">
                      <p>Total</p>
                      <Price
                        className="text-right text-base text-black dark:text-white"
                        amount={cart.cost.totalAmount.amount}
                        currencyCode={cart.cost.totalAmount.currencyCode}
                      />
                    </div>
                  </div>
                  <a
                    href={cart.checkoutUrl}
                    className="block w-full rounded-full bg-secondary p-3 text-center text-sm font-medium text-white opacity-90 hover:opacity-100"
                  >
                    Proceed to Checkout
                  </a>
                </div>
              )}
            </DialogPanel>
          </TransitionChild>
        </Dialog>
      </Transition>
    </>
  );
}