'use client';

import { useEffect, useState } from 'react';
import Link from 'next/link';
import { useCart } from '@/lib/cartStore';
import { getColorName } from '@/lib/colorNames';
import Price from '@/components/Price';

export default function CartPage() {
  const [mounted, setMounted] = useState(false);
  const items = useCart((s) => s.items);
  const removeItem = useCart((s) => s.removeItem);
  const setQuantity = useCart((s) => s.setQuantity);
  const total = useCart((s) => s.total());
  const hasCustomDesign = items.some((item) => {
    try {
      const design = typeof item.designJson === 'string' ? JSON.parse(item.designJson) : item.designJson;
      return (design.front?.length ?? 0) > 0 || (design.back?.length ?? 0) > 0;
    } catch {
      return false;
    }
  });

  useEffect(() => setMounted(true), []);

  const handleCheckout = () => {
    // Set flag so LogoutOnUnload doesn't clear cart during navigation to checkout
    if (typeof window !== 'undefined') {
      sessionStorage.setItem('isCheckingOut', 'true');
      console.log('💳 Cart checkout button clicked - set isCheckingOut flag');
    }
    window.location.href = '/checkout';
  };

  if (!mounted) return null;

  if (items.length === 0) {
    return (
      <div className="mx-auto max-w-2xl px-6 py-20 text-center">
        <h1 className="font-display text-4xl">Your bag</h1>
        <p className="mt-4 text-muted">Nothing in here yet.</p>
        <div className="mt-8 flex flex-wrap items-center justify-center gap-3">
          <Link
            href="/made-to-order"
            className="bg-clay px-6 py-3 text-sm font-medium text-paper hover:bg-clay-dark"
          >
            Start designing
          </Link>
          <Link
            href="/products"
            className="border-2 border-ink px-6 py-3 text-sm font-medium text-ink hover:border-clay hover:text-clay"
          >
            Shop ready-made
          </Link>
        </div>
      </div>
    );
  }

  return (
    <div className="mx-auto max-w-4xl px-6 py-12">
      <h1 className="font-display text-4xl">Your bag</h1>

      <div className="mt-8 divide-y divide-line border-t border-line">
        {items.map((item) => {
          const design = typeof item.designJson === 'string' ? JSON.parse(item.designJson) : item.designJson;
          const hasFront = (design.front?.length ?? 0) > 0;
          const hasBack = (design.back?.length ?? 0) > 0;

          return (
          <div key={item.cartItemId} className="flex flex-wrap items-center gap-4 py-6">
            <div className="h-24 w-24 shrink-0 border border-line bg-surface p-1">
              {item.placementPreviewUrl || item.designPreviewUrl ? (
                <img
                  src={item.placementPreviewUrl ?? item.designPreviewUrl}
                  alt={item.name}
                  className="h-full w-full object-contain"
                />
              ) : (
                <div className="flex h-full w-full items-center justify-center text-xs text-muted">No preview</div>
              )}
            </div>

            <div className="min-w-[160px] flex-1">
              <p className="font-display text-lg">{item.name}</p>
              <div className="mt-1 flex items-center gap-3 text-sm text-muted">
                <span className="flex items-center gap-1.5">
                  <span
                    className="h-3.5 w-3.5 rounded-full border border-line"
                    style={{ backgroundColor: item.color }}
                    title={item.color}
                  />
                  <span>{getColorName(item.color)}</span>
                </span>
                {item.size && <span>Size {item.size}</span>}
              </div>
              {(hasFront || hasBack) && (
                <div className="mt-1">
                  <p className="text-xs text-muted">
                    Custom design
                    {hasFront && hasBack
                      ? ' — front & back'
                      : hasBack
                        ? ' — back'
                        : ' — front'}
                  </p>
                  <div className="mt-1 flex gap-3">
                    {hasFront && item.designPreviewUrl && (
                      <a
                        href={item.designPreviewUrl}
                        download={`${item.slug}-front-print.png`}
                        className="text-xs text-clay hover:text-clay-dark"
                      >
                        Download front PNG
                      </a>
                    )}
                    {hasBack && item.designPreviewUrlBack && (
                      <a
                        href={item.designPreviewUrlBack}
                        download={`${item.slug}-back-print.png`}
                        className="text-xs text-clay hover:text-clay-dark"
                      >
                        Download back PNG
                      </a>
                    )}
                  </div>
                </div>
              )}
            </div>

            <div className="flex items-center border border-ink">
              <button
                onClick={() => setQuantity(item.cartItemId, item.quantity - 1)}
                className="px-3 py-2 text-sm"
                aria-label="Decrease quantity"
              >
                −
              </button>
              <span className="w-10 text-center font-mono text-sm">{item.quantity}</span>
              <button
                onClick={() => setQuantity(item.cartItemId, item.quantity + 1)}
                className="px-3 py-2 text-sm"
                aria-label="Increase quantity"
              >
                +
              </button>
            </div>

            <div className="w-24 text-right font-mono text-sm">
              {Number.isFinite(item.unitPrice) ? (
                <Price cents={item.unitPrice * item.quantity} />
              ) : (
                <span className="text-muted">—</span>
              )}
            </div>

            <button
              onClick={() => removeItem(item.cartItemId)}
              className="tag-label text-muted hover:text-splash-pink"
            >
              Remove
            </button>
          </div>
          );
        })}
      </div>

      {hasCustomDesign && (
        <div className="mt-8 border border-splash-orange bg-splash-orange/5 px-4 py-3 text-sm">
          <p className="font-medium text-ink">Please check your design before checking out</p>
          <p className="mt-1 text-muted">
            We print exactly what&apos;s shown in your preview above — spelling, wording, and
            approximate placement included. Once your order&apos;s placed, that design goes straight to print,
            so take a moment to make sure everything looks right.
          </p>
        </div>
      )}

      <div className="mt-8 flex flex-col items-end gap-4">
        <div className="flex items-baseline gap-3">
          <span className="tag-label">Subtotal</span>
          <span className="font-mono text-xl">
            <Price cents={total} />
          </span>
        </div>

        <div className="w-full max-w-xs">
          <button
            onClick={handleCheckout}
            className="w-full bg-clay px-6 py-3 text-sm font-medium text-paper transition-colors hover:bg-clay-dark"
          >
            Checkout
          </button>
          <p className="mt-2 text-center text-xs text-muted">You&apos;ll enter payment details on the next step.</p>
          <p className="mt-1 text-center text-xs text-muted">
            By placing an order you agree to our{' '}
            <Link href="/terms" className="text-clay hover:text-clay-dark">
              Terms
            </Link>{' '}
            and{' '}
            <Link href="/returns" className="text-clay hover:text-clay-dark">
              Returns policy
            </Link>
            .
          </p>
        </div>
      </div>
    </div>
  );
}