import { Link } from "@remix-run/react";
import { useRef, useState, useEffect } from "react";
import { motion } from "framer-motion";
import { ChevronLeft, ChevronRight, Images } from "lucide-react";
import { Skeleton } from "./ui/skeleton";
import { ErrorState } from "./UiProvider";
import discountRed from "~/assets/icons/product/discount-red.svg";
import placeholderImage from "~/assets/icons/product.png";
import SellerChip from "./SellerChip";

interface HorizontalProduct {
  id?: string;
  title?: string;
  images?: string[];
  discountPercent?: number;
  discountPrice?: number;
  basePrice?: number;
  sellerName?: string;
  sellerLogo?: string | null;
  sellerUsername?: string;
}

const HorizontalProductList = ({
  products,
  isLoading,
  isError,
  refetch,
  storeId,
  storePage,
}: {
  products: HorizontalProduct[];
  isLoading: boolean;
  isError: boolean;
  refetch: () => void;
  storeId?: string;
  storePage?: boolean;
}) => {
  const scrollContainerRef = useRef<HTMLDivElement>(null);
  const [showLeftButton, setShowLeftButton] = useState(false);
  const [showRightButton, setShowRightButton] = useState(false);
  const [currentPage, setCurrentPage] = useState(0);

  const totalPages = Math.ceil(products.length / 2);

  const checkScrollButtons = () => {
    if (!scrollContainerRef.current) return;

    const { scrollLeft, scrollWidth, clientWidth } = scrollContainerRef.current;

    // Calculate max scroll position
    const maxScroll = scrollWidth - clientWidth;

    // For RTL, scrollLeft might be negative or start from max
    // Check if we can scroll in each direction
    const canScrollRight = Math.abs(scrollLeft) > 100;
    const canScrollLeft = Math.abs(scrollLeft) < maxScroll - 100;

    setShowRightButton(canScrollRight);
    setShowLeftButton(canScrollLeft);

    // Calculate current page based on scroll position
    const page = Math.round(Math.abs(scrollLeft) / clientWidth);
    setCurrentPage(page);
  };

  useEffect(() => {
    // Small delay to ensure content is rendered
    const timer = setTimeout(() => {
      checkScrollButtons();
    }, 100);

    const container = scrollContainerRef.current;
    if (container) {
      container.addEventListener("scroll", checkScrollButtons);
      window.addEventListener("resize", checkScrollButtons);
      return () => {
        container.removeEventListener("scroll", checkScrollButtons);
        window.removeEventListener("resize", checkScrollButtons);
      };
    }
    return () => clearTimeout(timer);
  }, [products]);

  const scrollToNext = () => {
    if (!scrollContainerRef.current) return;
    const container = scrollContainerRef.current;
    const scrollAmount = container.clientWidth;
    container.scrollBy({ left: scrollAmount, behavior: "smooth" });
  };

  const scrollToPrev = () => {
    if (!scrollContainerRef.current) return;
    const container = scrollContainerRef.current;
    const scrollAmount = container.clientWidth;
    container.scrollBy({ left: -scrollAmount, behavior: "smooth" });
  };

  if (isLoading) {
    return <HorizontalSkeleton />;
  }

  if (isError) {
    return (
      <div className="px-4">
        <ErrorState onRetry={refetch} />
      </div>
    );
  }

  if (products.length === 0) {
    return null;
  }

  return (
    <div className="w-full flex flex-col gap-3">
      {/* Scroll Container */}
      <div
        ref={scrollContainerRef}
        className="w-full overflow-x-auto scrollbar-hide snap-x snap-mandatory px-4"
      >
        <div className="flex" style={{ width: "max-content" }}>
          {products.map((product, index) => (
            <div
              key={product.id || index}
              className="flex flex-col gap-2 pr-4 snap-start"
              style={{ width: "calc(50vw - 14px)", maxWidth: "220px" }}
            >
              <Link
                to={`${storePage ? `/store/${storeId}/product/${product.id}` : `/product/${product.id}`}`}
                className="block w-full"
              >
                <div className="relative rounded-lg overflow-hidden h-[180px]">
                  {/* Single Image Display */}
                  <ProductThumbnail
                    image={product.images?.[0]}
                    imageCount={product.images?.length || 0}
                    title={product.title}
                  />
                  {/* Discount badge */}
                  {product.discountPercent && product.discountPercent !== 0 && (
                    <DiscountBadge discountPercent={product.discountPercent} />
                  )}
                  {/* Overlay info */}
                  <div className="absolute bottom-0 left-0 right-0 bg-gradient-to-t from-black/70 via-black/40 to-transparent p-2 pt-6 pointer-events-none">
                    <SellerChip
                      name={product.sellerName}
                      logo={product.sellerLogo}
                    />
                    <div className="flex w-full justify-between gap-1">
                      {/* Title */}
                      <h3 className="text-white text-xs font-semibold line-clamp-1 mb-0.5">
                        {product.title}
                      </h3>
                      {/* Price */}
                      <div className="flex flex-col items-center gap-0 relative">
                        {product.discountPrice && (
                          <p className="text-white text-xs font-bold">
                            {`${product.discountPrice.toLocaleString()}`}
                            <span className="text-white text-[8px] mr-[2px]">
                              تومان
                            </span>
                          </p>
                        )}
                        {product.basePrice && product.discountPercent ? (
                          <p className="text-white/80 text-[10px] line-through absolute bottom-4 left-0">
                            {product.basePrice.toLocaleString()}
                          </p>
                        ) : null}
                      </div>
                    </div>
                  </div>
                </div>
              </Link>
            </div>
          ))}
        </div>
      </div>
      {/* Navigation Buttons Row */}
      {products.length > 2 && (
        <div className="flex items-center justify-center gap-3 px-4">
          <motion.button
            whileHover={!showRightButton ? {} : { scale: 1.1 }}
            whileTap={!showRightButton ? {} : { scale: 0.95 }}
            transition={{ type: "spring", stiffness: 400, damping: 25 }}
            onClick={scrollToNext}
            disabled={!showRightButton}
            aria-label="Next products"
          >
            <ChevronRight
              size={20}
              className={showRightButton ? "text-BLACK" : "text-GRAY"}
            />
          </motion.button>

          {/* Dots indicator */}
          <div className="flex gap-1.5">
            {Array.from({ length: totalPages }).map((_, i) => (
              <div
                key={i}
                className={`h-1.5 rounded-full transition-all duration-300 ${
                  i === currentPage ? "w-6 bg-BLACK" : "w-1.5 bg-GRAY3"
                }`}
              />
            ))}
          </div>

          <motion.button
            whileHover={!showLeftButton ? {} : { scale: 1.1 }}
            whileTap={!showLeftButton ? {} : { scale: 0.95 }}
            transition={{ type: "spring", stiffness: 400, damping: 25 }}
            onClick={scrollToPrev}
            disabled={!showLeftButton}
            aria-label="Previous products"
          >
            <ChevronLeft
              size={20}
              className={showLeftButton ? "text-BLACK" : "text-GRAY"}
            />
          </motion.button>
        </div>
      )}
    </div>
  );
};

// Simple thumbnail component - shows only first image with count badge
const ProductThumbnail = ({
  image,
  imageCount,
  title,
}: {
  image?: string;
  imageCount: number;
  title?: string;
}) => {
  return (
    <>
      <img
        src={image || placeholderImage}
        alt={title || "محصول"}
        className={`w-full h-full ${image ? "object-cover" : "object-contain bg-GRAY4"}`}
        loading="lazy"
        onError={(e) => {
          e.currentTarget.src = placeholderImage;
          e.currentTarget.style.objectFit = "contain";
          e.currentTarget.className = "w-full h-full object-contain bg-GRAY4";
        }}
      />
      {/* Image count badge - only show if more than 1 image */}
      {imageCount > 1 && (
        <div className="absolute top-2 left-2 z-10 bg-DARK_OVERLAY/80 text-WHITE px-2 py-1 rounded-full flex items-center gap-1">
          <Images size={12} />
          <span className="text-[12px] font-medium">{imageCount}</span>
        </div>
      )}
    </>
  );
};

const DiscountBadge = ({ discountPercent }: { discountPercent?: number }) => {
  return (
    <div className="absolute items-center gap-1 flex top-1 right-1 z-10 bg-[#FDFDFD]/75 text-[#FF3B30] py-[2px] px-2 rounded-[15px]">
      <p
        className="text-B14 font-bold leading-[20px]"
        dir="ltr"
        style={{ fontFamily: "Arial, sans-serif" }}
      >
        {discountPercent}
      </p>
      <img src={discountRed} alt="discount-red" className="w-5 h-5" />
    </div>
  );
};

const HorizontalSkeleton = () => {
  return (
    <div className="w-full overflow-x-auto scrollbar-hide">
      <div className="flex gap-4 px-4" style={{ width: "max-content" }}>
        {Array(6)
          .fill(1)
          .map((_, index) => (
            <Skeleton
              key={index}
              className="flex-shrink-0"
              style={{
                width: "calc(50vw - 32px)",
                maxWidth: "220px",
                height: "180px",
              }}
            />
          ))}
      </div>
    </div>
  );
};

export default HorizontalProductList;
