import {
  json,
  type LoaderFunctionArgs,
  type MetaFunction,
} from "@remix-run/node";
import { useParams, useSearchParams } from "@remix-run/react";
import { useToast } from "../hooks/use-toast";
import {
  useGetCartDetails,
  useUpdateCartItemQuantity,
  useRemoveFromCart,
} from "../requestHandler/use-cart-hooks";
import { useCreateShippingInfo } from "../requestHandler/use-shipping-hooks";
import { useCallback, useEffect, useState } from "react";
import { CartHeader } from "../components/cart/CartHeader";
import { CartItem } from "../components/cart/CartItem";
import { CartSummary } from "../components/cart/CartSummary";
import { ShippingInformation } from "../components/cart/ShippingInformation";
import { ReceiverInformation } from "../components/cart/ReceiverInformation";
import { useCashOutCart } from "../requestHandler/use-order-hooks";
import {
  Address,
  CartDetail as CartDetailType,
  CartItem as CartItemType,
  SellerCourierList,
} from "src/api/types";
import UiProvider from "~/components/UiProvider";

export const meta: MetaFunction = () => {
  return [
    { title: "سبد خرید - ویترون" },
    {
      name: "description",
      content:
        "مدیریت سبد خرید شما در ویترون. بررسی محصولات، انتخاب روش ارسال و تکمیل فرآیند خرید.",
    },
    {
      name: "keywords",
      content: "سبد خرید، خرید آنلاین، پرداخت، ارسال، ویترون",
    },
    { name: "robots", content: "noindex, follow" },
    { property: "og:title", content: "سبد خرید - ویترون" },
    {
      property: "og:description",
      content:
        "مدیریت سبد خرید شما در ویترون. بررسی محصولات، انتخاب روش ارسال و تکمیل فرآیند خرید.",
    },
    { property: "og:type", content: "website" },
    { name: "twitter:card", content: "summary" },
    { name: "twitter:title", content: "سبد خرید - ویترون" },
    {
      name: "twitter:description",
      content:
        "مدیریت سبد خرید شما در ویترون. بررسی محصولات، انتخاب روش ارسال و تکمیل فرآیند خرید.",
    },
  ];
};

// Server-side loader to fetch initial cart data
export async function loader({ params }: LoaderFunctionArgs) {
  const { cartId } = params;
  if (!cartId) {
    throw new Response("Missing cart ID", { status: 400 });
  }
  return json({ cartId });
}

// Main Cart Component
export default function CartDetail() {
  const { cartId } = useParams();
  const [searchParams, setSearchParams] = useSearchParams();
  const {
    data: cart,
    isLoading: isLoadingCart,
    refetch,
    isError,
  } = useGetCartDetails(cartId || "");
  const updateMutation = useUpdateCartItemQuantity();
  const removeMutation = useRemoveFromCart();
  const { toast } = useToast();
  const [step, setStep] = useState<number>(0);
  const createShippingInfo = useCreateShippingInfo();
  const cashOutMutation = useCashOutCart(cartId || "");

  // Calculate total price of all items in the cart
  const calculateTotal = useCallback(
    (
      cart: CartDetailType | null | undefined,
      deliveryPrice?: number | null,
      discountValue?: number | null
    ) => {
      if (!cart || !cart.items || cart.items.length === 0) return "0";

      let total = cart.items.reduce((sum: number, item: CartItemType) => {
        if (item.productVariant?.stock && item.productVariant?.stock > 0) {
          const price =
            Number(
              item.productVariant?.discountPrice || item.productVariant?.price
            ) * item.quantity;
          return sum + price;
        }
        return sum;
      }, 0);
      if (deliveryPrice) {
        total += deliveryPrice;
      }
      if (discountValue) {
        total -= discountValue;
      }

      return total.toString();
    },
    []
  );
  // Handle quantity change
  const handleQuantityChange = async (itemId: string, newQuantity: number) => {
    if (newQuantity < 1) return;

    try {
      await updateMutation.mutateAsync({ itemId, quantity: newQuantity });
    } catch (error) {
      console.error("Error updating item quantity:", error);
      toast({
        title: "خطا",
        description: "بروزرسانی تعداد محصول با مشکل مواجه شد",
        variant: "destructive",
      });
    }
  };

  // Handle item removal
  const handleRemoveItem = async (itemId: string) => {
    try {
      await removeMutation.mutateAsync(itemId);

      toast({
        title: "سبد خرید",
        description: "محصول با موفقیت از سبد خرید حذف شد",
        variant: "default",
      });
    } catch (error) {
      console.error("Error removing item:", error);
      toast({
        title: "خطا",
        description: "حذف محصول از سبد خرید با مشکل مواجه شد",
        variant: "destructive",
      });
    }
  };
  const [selectedAddressInfo, setSelectedAddressInfo] =
    useState<Address | null>(null);
  const [selectedCourierInfo, setSelectedCourierInfo] =
    useState<SellerCourierList | null>(null);
  const [shippingInfoId, setShippingInfoId] = useState<string>("");
  const [isCreatingOrder, setIsCreatingOrder] = useState<boolean>(false);
  const [shippingInfoIsLoading, setShippingInfoIsLoading] =
    useState<boolean>(false);

  // Initialize step from URL query parameter when component mounts
  useEffect(() => {
    const stepParam = searchParams.get("step");
    if (stepParam) {
      const newStep = parseInt(stepParam, 10);
      if (!isNaN(newStep) && newStep >= 0 && newStep <= 2) {
        setStep(newStep);
      }
      // Clean up the URL by removing the step parameter
      const newSearchParams = new URLSearchParams(searchParams);
      newSearchParams.delete("step");
      setSearchParams(newSearchParams, { replace: true });
    }
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, []); // Only run once on mount

  useEffect(() => {
    console.log("selectedCourierInfo", selectedCourierInfo);
  }, [selectedCourierInfo]);
  const continueHandler = async () => {
    if (step === 0) {
      setStep(1);
    } else if (step === 1) {
      const isFaceToFace = selectedCourierInfo?.courierIsFaceToFace;
      if (!isFaceToFace && (!selectedAddressInfo || !selectedAddressInfo?.id)) {
        toast({
          title: "خطا",
          description: "لطفا آدرس را انتخاب کنید",
          variant: "destructive",
        });
        return;
      }

      if (!selectedCourierInfo || !selectedCourierInfo?.id) {
        toast({
          title: "خطا",
          description: "لطفا روش ارسال را انتخاب کنید",
          variant: "destructive",
        });
        return;
      }

      try {
        const response = await createShippingInfo.mutateAsync({
          address: isFaceToFace ? undefined : selectedAddressInfo?.id,
          sellerCourier: selectedCourierInfo.id,
        });
        setShippingInfoId(response.id || "");
        setStep(2);
      } catch (error) {
        console.error("Error creating shipping info:", error);
        toast({
          title: "خطا",
          description: "ثبت اطلاعات ارسال با مشکل مواجه شد",
          variant: "destructive",
        });
      }
    } else if (step === 2) {
      if (!shippingInfoId) {
        toast({
          title: "Error",
          description: "Shipping information ID is missing.",
          variant: "destructive",
        });
        return;
      }
      setIsCreatingOrder(true);
      try {
        console.log(
          `Initiating cash out for cart ${cartId} with shipping info ID: ${shippingInfoId}`
        );
        const response = await cashOutMutation.mutateAsync({
          shippingInfoId: shippingInfoId,
        });
        console.log("Cash out mutation initiated.");
        window.location.href = response.redirect;
      } catch (error) {
        console.error(
          "Error caught in continueHandler during cash out:",
          error
        );
        toast({
          title: "عدم وجود محصول",
          description:
            "موجودی این محصول کمتر از تعداد درخواستی شما است. لطفا تعداد محصولات موجود را چک کنید.",
          variant: "destructive",
        });
      } finally {
        setIsCreatingOrder(false);
      }
    }
  };

  return (
    <div className="bg-background pb-14">
      <CartHeader cart={cart} step={step} setStep={setStep} />

      {/* Cart Content */}
      <div className=" gap-1 flex flex-col">
        <UiProvider
          isLoading={isLoadingCart}
          isEmpty={!cart || cart.items?.length === 0}
          type="cart"
          isError={isError}
          onRetry={refetch}
        >
          <div className="lg:grid lg:grid-cols-[1fr_360px] lg:gap-7 lg:items-start lg:max-w-[1320px] lg:mx-auto lg:w-full lg:px-8 lg:py-6">
            <div className="flex flex-col w-full">
              {step === 0 && (
                <div className="flex flex-col w-full">
                  {cart?.items?.map((item, index) => (
                    <CartItem
                      key={item.id}
                      item={item}
                      onQuantityChange={handleQuantityChange}
                      onRemoveItem={handleRemoveItem}
                      isLoading={removeMutation.isPending}
                      hasBorder={
                        !!(cart?.items && index !== cart?.items?.length - 1)
                      }
                    />
                  ))}
                </div>
              )}
              {step === 1 && (
                <ShippingInformation
                  sellerId={cart?.seller?.username || ""}
                  total={calculateTotal(cart)}
                  setSelectedAddressInfo={setSelectedAddressInfo}
                  setSelectedCourierInfo={setSelectedCourierInfo}
                  setShippingInfoIsLoading={setShippingInfoIsLoading}
                  selectedAddressInfo={selectedAddressInfo}
                  cartId={cartId}
                />
              )}
              {step === 2 && (
                <ReceiverInformation
                  discountValue={Number(cart?.discountValue) || null}
                  cartItems={cart?.items || []}
                  selectedAddressInfo={selectedAddressInfo}
                  selectedCourierInfo={selectedCourierInfo}
                  total={calculateTotal(
                    cart,
                    selectedCourierInfo?.courierIsFreightCollect ? 0 : selectedCourierInfo?.deliveryPrice,
                    Number(cart?.discountValue)
                  )}
                />
              )}
            </div>

            <div className="lg:sticky lg:top-[88px]">
              <CartSummary
                total={calculateTotal(
                  cart,
                  step === 2 && !selectedCourierInfo?.courierIsFreightCollect ? selectedCourierInfo?.deliveryPrice : 0,
                  step === 2 ? Number(cart?.discountValue) : 0
                )}
                onContinue={() => continueHandler()}
                step={step}
                isLoading={
                  isCreatingOrder ||
                  cashOutMutation.isPending ||
                  shippingInfoIsLoading
                }
              />
            </div>
          </div>
        </UiProvider>
      </div>
    </div>
  );
}