'use client';

import Link from 'next/link';
import Image from 'next/image';
import { useEffect, useState } from 'react';
import BlurHashImage from '@/components/ui/BlurHashImage';
import { ProductResponse } from '@/services/api/catalogService';
import { formatCurrency, getCatalogPriceInfo, getImageUrl } from '@/lib/utils';

interface YouMayAlsoLikeProps {
  products: ProductResponse[];
}

function priceLabel(product: ProductResponse): { current: string; compare?: string; range: boolean } {
  const { price, priceMax, oldPrice } = getCatalogPriceInfo(product);

  if (!price) return { current: '—', range: false };

  if (priceMax && priceMax > price) {
    return {
      current: `${formatCurrency(price)} – ${formatCurrency(priceMax)}`,
      range: true,
    };
  }

  return {
    current: formatCurrency(price),
    compare: oldPrice && oldPrice > price ? formatCurrency(oldPrice) : undefined,
    range: false,
  };
}

function discountPct(product: ProductResponse): number {
  const { discount } = getCatalogPriceInfo(product);
  return discount || 0;
}

function stableSaleSeconds(productId: string): number {
  let hash = 0;
  for (let i = 0; i < productId.length; i++) hash = (hash * 31 + productId.charCodeAt(i)) >>> 0;
  return 36 * 3600 + (hash % (48 * 3600));
}

function SaleCountdown({ productId }: { productId: string }) {
  const [remaining, setRemaining] = useState(() => stableSaleSeconds(productId));

  useEffect(() => {
    const t = setInterval(() => setRemaining((s) => (s > 0 ? s - 1 : 0)), 1000);
    return () => clearInterval(t);
  }, []);

  const days = Math.floor(remaining / 86400);
  const hrs = Math.floor((remaining % 86400) / 3600);
  const min = Math.floor((remaining % 3600) / 60);
  const sec = remaining % 60;
  const pad = (n: number) => String(n).padStart(2, '0');

  const units = [
    { val: pad(days), label: 'DAYS' },
    { val: pad(hrs), label: 'HRS' },
    { val: pad(min), label: 'MIN' },
    { val: pad(sec), label: 'SEC' },
  ];

  return (
    <div className="flex items-center justify-center gap-1 my-2">
      {units.map((u) => (
        <div key={u.label} className="flex flex-col items-center">
          <span className="min-w-[28px] h-7 px-1 bg-white border border-gray-200 rounded-sm text-[12px] font-bold text-[#e53935] flex items-center justify-center">
            {u.val}
          </span>
          <span className="text-[8px] font-semibold text-[#f48fb1] uppercase tracking-wide mt-0.5">{u.label}</span>
        </div>
      ))}
    </div>
  );
}

function Stars({ rating }: { rating: number }) {
  const filled = Math.round(rating || 5);
  return (
    <div className="flex justify-center gap-0.5 my-1.5" aria-label={`${filled} out of 5 stars`}>
      {Array.from({ length: 5 }).map((_, i) => (
        <span key={i} className={i < filled ? 'text-orange-400' : 'text-gray-300'}>
          ★
        </span>
      ))}
    </div>
  );
}

export function YouMayAlsoLike({ products }: YouMayAlsoLikeProps) {
  if (!products.length) return null;

  return (
    <section className="mt-4 mb-10">
      <h3 className="text-[20px] font-semibold text-gray-800 mb-4 tracking-tight">You may also like...</h3>
      <div className="overflow-x-auto rounded-md border border-gray-200 bg-white">
        <div
          className="grid min-w-[860px]"
          style={{ gridTemplateColumns: `repeat(${Math.min(products.length, 5)}, minmax(168px, 1fr))` }}
        >
          {products.slice(0, 5).map((prod, index) => {
            const img = getImageUrl(prod.images?.[0]?.image_url || prod.variants?.[0]?.images?.[0]?.image_url);
            const off = discountPct(prod);
            const pricing = priceLabel(prod);
            const onSale = off > 0;

            return (
              <Link
                key={prod.product_id}
                href={`/products/${prod.slug}`}
                className={`relative p-5 text-center hover:bg-[#fafafa] transition-colors ${
                  index > 0 ? 'border-l border-gray-200' : ''
                }`}
              >
                {off > 0 && (
                  <span className="absolute top-3 right-3 bg-primary text-white text-[10px] font-bold px-1.5 py-0.5 rounded-sm">
                    -{off}%
                  </span>
                )}

                <div className="h-[140px] flex items-center justify-center mb-1">
                  <BlurHashImage
                    src={img}
                    alt={prod.name}
                    width={140}
                    height={140}
                    className="max-h-full max-w-full object-contain"
                  />
                </div>

                {onSale ? <SaleCountdown productId={prod.product_id} /> : <div className="h-[42px]" />}

                <p className="text-[13px] font-medium text-gray-800 leading-snug line-clamp-2 min-h-[36px]">
                  {prod.name}
                </p>
                <Stars rating={prod.rating || 5} />
                <div className="text-[13px]">
                  {pricing.compare && (
                    <span className="text-gray-400 line-through mr-1.5 font-normal">{pricing.compare}</span>
                  )}
                  <span className="font-bold text-gray-900">{pricing.current}</span>
                </div>
              </Link>
            );
          })}
        </div>
      </div>
    </section>
  );
}