import React, { useState, useCallback, useMemo, useRef, type ReactNode } from "react";
import { Box, type AlertColor } from "@mui/material";
import { NotificationContext } from "contexts/NotificationContext";
import NotificationItem from "contexts/NotificationItem";
import type { Notification } from "contexts/Notification";

export function NotificationProvider({ children }: { children: ReactNode }): React.JSX.Element {
    const nextId = useRef(0);
    const [notifications, setNotifications] = useState<Notification[]>([]);

    const addNotification = useCallback((title: string, message: string, severity: AlertColor) => {
        const id = nextId.current++;
        setNotifications((prev) => [...prev, { id, title, message, severity }]);
    }, []);

    const removeNotification = useCallback((id: number) => {
        setNotifications((prev) => prev.filter((n) => n.id !== id));
    }, []);

    const showSuccess = useCallback(
        (title: string, message: string) => addNotification(title, message, "success"),
        [addNotification],
    );
    const showError = useCallback(
        (title: string, message: string) => addNotification(title, message, "error"),
        [addNotification],
    );

    const value = useMemo(() => ({ showSuccess, showError }), [showSuccess, showError]);

    return (
        <NotificationContext.Provider value={value}>
            {children}
            <Box
                sx={{
                    position: "fixed",
                    top: 16,
                    left: "50%",
                    transform: "translateX(-50%)",
                    zIndex: (theme) => theme.zIndex.snackbar,
                    display: "flex",
                    flexDirection: "column",
                    gap: 1,
                    maxWidth: 500,
                    width: "100%",
                    pointerEvents: "none",
                }}
            >
                {notifications.map((n) => (
                    <NotificationItem key={n.id} notification={n} onClose={removeNotification} />
                ))}
            </Box>
        </NotificationContext.Provider>
    );
}