import theme from "@theme";
import { Button, Paper, Box, Typography, TableHead, TableRow, TableCell, TableBody, Table, Tooltip, Alert, Checkbox, FormControlLabel } from "@mui/material";
import Input from "@kitUI/input";
import { useCartStore } from "@root/stores/cart";
import { useState } from "react";
import { GridSelectionModel } from "@mui/x-data-grid";
import { testUser } from "@root/stores/mocks/user";
import { useDiscountStore } from "@root/stores/discounts";
import { calcCartData, createCartItem, findDiscountFactor, formatDiscountFactor } from "./calc";
import { useTariffStore } from "@root/stores/tariffs";
import { AnyDiscount, CartItemTotal } from "@root/model/cart";
import { findPrivilegeById } from "@root/stores/privileges";


interface Props {
    selectedTariffs: GridSelectionModel;
}

export default function Cart({ selectedTariffs }: Props) {
    const tariffs = useTariffStore(store => store.tariffs);
    const discounts = useDiscountStore(store => store.discounts);
    const cartTotal = useCartStore(state => state.cartTotal);
    const setCartTotal = useCartStore(store => store.setCartTotal);
    const [couponField, setCouponField] = useState<string>("");
    const [loyaltyField, setLoyaltyField] = useState<string>("");
    const [errorMessage, setErrorMessage] = useState<string | null>(null);
    const [isNonCommercial, setIsNonCommercial] = useState<boolean>(false);

    const cartRows = cartTotal?.items.map(cartItemTotal => {
        const privilege = findPrivilegeById(cartItemTotal.tariff.privilegeId);

        const service = privilege?.serviceKey;
        const serviceDiscount = service ? cartTotal.discountsByService[service] : null;

        const envolvedDiscountsElement = (
            <Box>
                {cartItemTotal.envolvedDiscounts.map((discount, index, arr) => (
                    <span key={discount._id}>
                        <DiscountTooltip
                            discount={discount}
                            cartItemTotal={cartItemTotal}
                        />
                        {index < arr.length - (serviceDiscount ? 0 : 1) &&
                            <span>,&nbsp;</span>
                        }
                    </span>
                ))}
                {serviceDiscount &&
                    <span>
                        <DiscountTooltip
                            discount={serviceDiscount}
                            cartItemTotal={cartItemTotal}
                        />
                    </span>
                }
            </Box>
        );

        const totalIncludingServiceDiscount = cartItemTotal.totalPrice * (serviceDiscount?.target.factor || 1);

        return {
            id: cartItemTotal.tariff.id,
            tariffName: cartItemTotal.tariff.name,
            privilegeDesc: privilege?.description ?? "Привилегия не найдена",
            envolvedDiscounts: envolvedDiscountsElement,
            price: totalIncludingServiceDiscount,
        };
    });

    const cartDiscounts = cartTotal?.envolvedCartDiscounts;
    const cartDiscountsResultFactor = cartDiscounts && cartDiscounts?.length > 1 && cartDiscounts.reduce((acc, discount) => acc * findDiscountFactor(discount), 1);

    const envolvedCartDiscountsElement = cartDiscounts && (
        <Box sx={{
            display: "inline-flex",
            flexWrap: "wrap",
        }}>
            {cartDiscounts?.map((discount, index, arr) => (
                <span key={discount._id}>
                    <DiscountTooltip
                        discount={discount}
                    />
                    {index < arr.length - 1 &&
                        <span>,&nbsp;</span>
                    }
                </span>
            ))}
            &nbsp;
            {cartDiscountsResultFactor && `= ${formatDiscountFactor(cartDiscountsResultFactor)}`}
        </Box>
    );

    function handleCalcCartClick() {
        const cartTariffs = tariffs.filter(tariff => selectedTariffs.includes(tariff.id));
        const cartItems = cartTariffs.map(tariff => createCartItem(tariff));

        let loyaltyValue = parseInt(loyaltyField);

        if (!isFinite(loyaltyValue)) loyaltyValue = 0;

        const activeDiscounts = discounts.filter(discount => !discount.disabled);

        const cartData = calcCartData({
            user: testUser,
            purchasesAmount: loyaltyValue,
            cartItems,
            discounts: activeDiscounts,
            isNonCommercial,
            coupon: couponField,
        });

        if (cartData instanceof Error) {
            setErrorMessage(cartData.message);
            return setCartTotal(null);
        }

        setErrorMessage(null);
        setCartTotal(cartData);
    }

    return (
        <Box
            component="section"
            sx={{
                border: "1px solid white",
                display: "flex",
                flexDirection: "column",
                alignItems: "center",
                width: "100%",
                pb: "20px",
                borderRadius: "4px",
            }}
        >
            <Typography variant="caption">
                корзина
            </Typography>
            <Paper
                variant="bar"
                sx={{
                    display: "flex",
                    alignItems: "center",
                    justifyContent: "space-between",
                    gap: "20px",
                }}
            >
                <FormControlLabel
                    checked={isNonCommercial}
                    onChange={(e, checked) => setIsNonCommercial(checked)}
                    control={<Checkbox
                        sx={{
                            color: theme.palette.secondary.main,
                            "&.Mui-checked": {
                                color: theme.palette.secondary.main,
                            },
                        }}
                    />}
                    label="НКО"
                    sx={{
                        color: theme.palette.secondary.main,
                    }}
                />
                <Box
                    sx={{
                        border: "1px solid white",
                        padding: "3px",
                        display: "flex",
                        flexDirection: "column"
                    }}
                >
                    <Input
                        label="промокод"
                        size="small"
                        value={couponField}
                        onChange={e => setCouponField(e.target.value)}
                        InputProps={{
                            style: {
                                backgroundColor: theme.palette.content.main,
                                color: theme.palette.secondary.main,
                            }
                        }}
                        InputLabelProps={{
                            style: {
                                color: theme.palette.secondary.main
                            }
                        }}
                    />
                </Box>
                {cartTotal?.couponState && (
                    cartTotal.couponState === "applied" ?
                        <Alert severity="success">Купон применен!</Alert>
                        :
                        <Alert severity="error">Подходящий купон не найден!</Alert>
                )}
                <Box
                    sx={{
                        border: "1px solid white",
                        padding: "3px",
                        display: "flex",
                        flexDirection: "column",
                        ml: "auto",
                    }}
                >
                    <Input
                        label="лояльность"
                        size="small"
                        type="number"
                        value={loyaltyField}
                        onChange={e => setLoyaltyField(e.target.value)}
                        InputProps={{
                            style: {
                                backgroundColor: theme.palette.content.main,
                                color: theme.palette.secondary.main,
                            }
                        }}
                        InputLabelProps={{
                            style: {
                                color: theme.palette.secondary.main
                            }
                        }}
                    />
                </Box>
                <Button onClick={handleCalcCartClick}>рассчитать</Button>
            </Paper>

            {cartTotal?.items && cartTotal.items.length > 0 &&
                <>
                    <Table sx={{
                        width: "90%",
                        margin: "5px",
                        border: "2px solid",
                        borderColor: theme.palette.secondary.main,
                    }} aria-label="simple table">
                        <TableHead>
                            <TableRow sx={{
                                borderBottom: "2px solid",
                                borderColor: theme.palette.grayLight.main,
                                height: "100px"
                            }}>
                                <TableCell>
                                    <Typography
                                        variant="h4"
                                        sx={{ color: theme.palette.secondary.main }}
                                    >Имя</Typography>
                                </TableCell>
                                <TableCell>
                                    <Typography
                                        variant="h4"
                                        sx={{ color: theme.palette.secondary.main }}
                                    >Описание</Typography>
                                </TableCell>
                                <TableCell>
                                    <Typography
                                        variant="h4"
                                        sx={{ color: theme.palette.secondary.main }}
                                    >Скидки</Typography>
                                </TableCell>
                                <TableCell>
                                    <Typography
                                        variant="h4"
                                        sx={{ color: theme.palette.secondary.main }}
                                    >стоимость</Typography>
                                </TableCell>
                            </TableRow>
                        </TableHead>
                        <TableBody>
                            {cartRows?.map(row => (
                                <TableRow
                                    key={row.id}
                                    sx={{
                                        borderBottom: "2px solid",
                                        borderColor: theme.palette.grayLight.main,
                                    }}
                                >
                                    <TableCell sx={{
                                        color: theme.palette.secondary.main,
                                    }}>{row.tariffName}</TableCell>
                                    <TableCell sx={{
                                        color: theme.palette.secondary.main,
                                    }}>{row.privilegeDesc}</TableCell>
                                    <TableCell sx={{
                                        color: theme.palette.secondary.main,
                                    }}>{row.envolvedDiscounts}</TableCell>
                                    <TableCell sx={{
                                        color: theme.palette.secondary.main,
                                    }}>{row.price.toFixed(2)} ₽</TableCell>
                                </TableRow>
                            ))}
                        </TableBody>
                    </Table>

                    <Typography id="transition-modal-title" variant="h6" sx={{
                        fontWeight: "normal",
                        textAlign: "center",
                        marginTop: "15px",
                        fontSize: "16px"
                    }}>
                        Скидки корзины: {envolvedCartDiscountsElement}
                    </Typography>

                    <Typography id="transition-modal-title" variant="h6" sx={{
                        fontWeight: "normal",
                        textAlign: "center",
                        marginTop: "10px"
                    }}>
                        ИТОГО: <span>{cartTotal?.totalPrice.toFixed(2)} ₽</span>
                    </Typography>
                </>
            }

            {errorMessage !== null &&
                <Alert variant="filled" severity="error" sx={{ mt: "20px" }}>
                    {errorMessage}
                </Alert>
            }

        </Box>
    );
}

function DiscountTooltip({ discount, cartItemTotal }: {
    discount: AnyDiscount;
    cartItemTotal?: CartItemTotal;
}) {
    const discountText = formatDiscountFactor(findDiscountFactor(discount));

    return (
        <Tooltip title={
            <>
                <Typography>Скидка: {discount?.name}</Typography>
                <Typography>{discount?.description}</Typography>
            </>
        }>
            <span>{discountText}</span>
        </Tooltip>
    );
}