'use client';

import { useCallback, useState } from 'react';

import { useRouter } from 'next/navigation';

import {
  StoreCart,
  StoreCartLineItem,
  StoreCartPromotion,
} from '@medusajs/types';
import { useTranslation } from 'react-i18next';

import { AccountBalanceSummary } from '@kit/accounts/services/account-balance.service';
import { Trans } from '@kit/ui/trans';

import { initiatePayment } from '../../_lib/server/cart-actions';
import CartForm, { CartFormOnSubmit } from './cart-form';
import CartFormContent from './cart-form-content';
import { EnrichedCartItem } from './types';

export default function Cart({
  accountId,
  cart,
  synlabAnalyses,
  ttoServiceItems,
  balanceSummary,
}: {
  accountId: string;
  cart:
    | (StoreCart & {
        promotions: StoreCartPromotion[];
      })
    | null;
  synlabAnalyses: StoreCartLineItem[];
  ttoServiceItems: EnrichedCartItem[];
  balanceSummary: AccountBalanceSummary | null;
}) {
  const {
    i18n: { language },
  } = useTranslation();

  const [isInitiatingSession, setIsInitiatingSession] = useState(false);
  const router = useRouter();
  const [unavailableLineItemIds, setUnavailableLineItemIds] =
    useState<string[]>();

  const getBalanceSummarySelection = useCallback(
    ({
      useCompanyBenefits,
    }: {
      useCompanyBenefits: boolean;
    }): {
      benefitsAmount: number;
      benefitsAmountTotal: number;
      montonioAmount: number;
    } => {
      if (!cart) {
        return {
          benefitsAmount: 0,
          benefitsAmountTotal: 0,
          montonioAmount: 0,
        };
      }

      const benefitsAmountTotal = balanceSummary?.totalBalance ?? 0;
      const cartTotal = cart.total;
      if (!useCompanyBenefits) {
        return {
          benefitsAmount: 0,
          benefitsAmountTotal,
          montonioAmount: cartTotal,
        };
      }

      const benefitsAmount =
        benefitsAmountTotal > cartTotal ? cartTotal : benefitsAmountTotal;
      const montonioAmount =
        benefitsAmount > 0 ? cartTotal - benefitsAmount : cartTotal;
      return {
        benefitsAmount,
        benefitsAmountTotal,
        montonioAmount,
      };
    },
    [balanceSummary, cart],
  );

  const items = cart?.items ?? [];
  const hasCartItems = cart && Array.isArray(items) && items.length > 0;

  if (!hasCartItems) {
    return (
      <div className="content-container py-5 lg:px-4">
        <div>
          <div
            className="flex flex-col items-center justify-center"
            data-testid="empty-cart-message"
          >
            <h4 className="text-center">
              <Trans i18nKey="cart:emptyCartMessage" />
            </h4>
            <p className="text-center">
              <Trans i18nKey="cart:emptyCartMessageDescription" />
            </p>
          </div>
        </div>
      </div>
    );
  }

  const initiateSession: CartFormOnSubmit = async ({ useCompanyBenefits }) => {
    setIsInitiatingSession(true);

    try {
      const { benefitsAmount } = getBalanceSummarySelection({
        useCompanyBenefits,
      });
      const { url, isFullyPaidByBenefits, orderId, unavailableLineItemIds } =
        await initiatePayment({
          accountId,
          benefitsAmount,
          cart: cart!,
          language,
        });
      if (unavailableLineItemIds) {
        setUnavailableLineItemIds(unavailableLineItemIds);
      }
      if (url) {
        window.location.href = url;
      } else if (isFullyPaidByBenefits) {
        if (typeof orderId !== 'number') {
          throw new Error('Order ID is missing');
        }
        router.push(`/home/order/${orderId}/confirmed`);
      }
    } catch (error) {
      console.error('Failed to initiate payment', error);
      setIsInitiatingSession(false);
    }
  };

  return (
    <div className="small:grid-cols-[1fr_360px] grid grid-cols-1 gap-x-40 lg:px-4">
      <CartForm cart={cart} onSubmit={initiateSession}>
        <CartFormContent
          cart={cart}
          synlabAnalyses={synlabAnalyses}
          ttoServiceItems={ttoServiceItems}
          unavailableLineItemIds={unavailableLineItemIds}
          isInitiatingSession={isInitiatingSession}
          getBalanceSummarySelection={getBalanceSummarySelection}
        />
      </CartForm>
    </div>
  );
}