"use client";

import { useState, useEffect } from "react";
import { Bell, Check } from "lucide-react";
import { Button } from "@/components/ui/button";
import {
  DropdownMenu,
  DropdownMenuContent,
  DropdownMenuItem,
  DropdownMenuLabel,
  DropdownMenuSeparator,
  DropdownMenuTrigger,
} from "@/components/ui/dropdown-menu";
import { Badge } from "@/components/ui/badge";
import { notificationApi } from "@/lib/api/notifications";
import { Notification } from "@/types/notification";
import { formatDistanceToNow } from "date-fns";
import Link from "next/link";
import { useRouter } from "next/navigation";

export function NotificationsDropdown() {
  const router = useRouter();
  const [notifications, setNotifications] = useState<Notification[]>([]);
  const [unreadCount, setUnreadCount] = useState(0);
  const [isOpen, setIsOpen] = useState(false);

  useEffect(() => {
    // Fetch notifications
    const fetchNotifications = async () => {
      try {
        const data = await notificationApi.getUnread();
        setNotifications(data.items);
        setUnreadCount(data.unreadCount);
      } catch (error) {
        console.error("Failed to fetch notifications", error);
      }
    };

    fetchNotifications();
  }, []);

  const handleMarkAsRead = async (id: number, e: React.MouseEvent) => {
    e.stopPropagation();
    await notificationApi.markAsRead(id);
    setNotifications((prev) =>
      prev.map((n) => (n.notification_id === id ? { ...n, is_read: true } : n))
    );
    setUnreadCount((prev) => Math.max(0, prev - 1));
  };

  const handleNotificationClick = async (notification: Notification) => {
    if (!notification.is_read) {
      await notificationApi.markAsRead(notification.notification_id);
      setUnreadCount((prev) => Math.max(0, prev - 1));
    }
    setIsOpen(false);
    if (notification.link) {
      router.push(notification.link);
    }
  };

  return (
    <DropdownMenu open={isOpen} onOpenChange={setIsOpen}>
      <DropdownMenuTrigger asChild>
        <Button variant="ghost" size="icon" className="relative">
          <Bell className="h-5 w-5 text-gray-600" />
          {unreadCount > 0 && (
            <Badge
              variant="destructive"
              className="absolute -top-1 -right-1 h-5 w-5 flex items-center justify-center p-0 text-[10px] rounded-full"
            >
              {unreadCount}
            </Badge>
          )}
        </Button>
      </DropdownMenuTrigger>

      <DropdownMenuContent align="end" className="w-80">
        <DropdownMenuLabel className="flex justify-between items-center">
          <span>Notifications</span>
          {unreadCount > 0 && (
            <span className="text-xs font-normal text-muted-foreground">
              {unreadCount} unread
            </span>
          )}
        </DropdownMenuLabel>
        <DropdownMenuSeparator />

        {notifications.length === 0 ? (
          <div className="p-8 text-center text-sm text-muted-foreground">
            No notifications
          </div>
        ) : (
          <div className="max-h-[400px] overflow-y-auto">
            {notifications.map((notification) => (
              <DropdownMenuItem
                key={notification.notification_id}
                className={`flex flex-col items-start p-3 cursor-pointer ${
                  !notification.is_read ? "bg-muted/30" : ""
                }`}
                onClick={() => handleNotificationClick(notification)}
              >
                <div className="flex w-full justify-between items-start gap-2">
                  <div className="font-medium text-sm line-clamp-1">
                    {notification.title}
                  </div>
                  {!notification.is_read && (
                    <Button
                      variant="ghost"
                      size="icon"
                      className="h-5 w-5 text-muted-foreground hover:text-primary"
                      onClick={(e) => handleMarkAsRead(notification.notification_id, e)}
                      title="Mark as read"
                    >
                      <Check className="h-3 w-3" />
                    </Button>
                  )}
                </div>
                <div className="text-xs text-muted-foreground mt-1 line-clamp-2">
                  {notification.message}
                </div>
                <div className="text-[10px] text-muted-foreground mt-2 w-full text-right">
                  {formatDistanceToNow(new Date(notification.created_at), {
                    addSuffix: true,
                  })}
                </div>
              </DropdownMenuItem>
            ))}
          </div>
        )}

        <DropdownMenuSeparator />
        <DropdownMenuItem className="text-center justify-center text-xs text-muted-foreground cursor-pointer">
          View All Notifications
        </DropdownMenuItem>
      </DropdownMenuContent>
    </DropdownMenu>
  );
}