'use client';

import Link from 'next/link';
import { useParams, usePathname, useRouter } from 'next/navigation';
import { type User } from 'next-auth';
import { useEffect, useState } from 'react';
import { toast } from 'sonner';
import useSWR from 'swr';

import {
  InfoIcon,
  MoreHorizontalIcon,
  TrashIcon,
} from '@/components/custom/icons';
import {
  AlertDialog,
  AlertDialogAction,
  AlertDialogCancel,
  AlertDialogContent,
  AlertDialogDescription,
  AlertDialogFooter,
  AlertDialogHeader,
  AlertDialogTitle,
} from '@/components/ui/alert-dialog';
import {
  DropdownMenu,
  DropdownMenuContent,
  DropdownMenuItem,
  DropdownMenuTrigger,
} from '@/components/ui/dropdown-menu';
import {
  SidebarGroup,
  SidebarGroupContent,
  SidebarGroupLabel,
  SidebarMenu,
  SidebarMenuAction,
  SidebarMenuButton,
  SidebarMenuItem,
  useSidebar,
} from '@/components/ui/sidebar';
import { Chat } from '@/db/schema';
import { fetcher, getTitleFromChat } from '@/lib/utils';

export function SidebarHistory({ user }: { user: User | undefined }) {
  const { setOpenMobile } = useSidebar();
  const { id } = useParams();
  const pathname = usePathname();
  const {
    data: history,
    isLoading,
    mutate,
  } = useSWR<Array<Chat>>(user ? '/api/history' : null, fetcher, {
    fallbackData: [],
  });

  useEffect(() => {
    mutate();
  }, [pathname, mutate]);

  const [deleteId, setDeleteId] = useState<string | null>(null);
  const [showDeleteDialog, setShowDeleteDialog] = useState(false);
  const router = useRouter();
  const handleDelete = async () => {
    const deletePromise = fetch(`/api/chat?id=${deleteId}`, {
      method: 'DELETE',
    });

    toast.promise(deletePromise, {
      loading: 'Deleting chat...',
      success: () => {
        mutate((history) => {
          if (history) {
            return history.filter((h) => h.id !== id);
          }
        });
        return 'Chat deleted successfully';
      },
      error: 'Failed to delete chat',
    });

    setShowDeleteDialog(false);
    if (deleteId === id) {
      router.push('/');
    }
  };

  if (!user) {
    return (
      <SidebarGroup>
        <SidebarGroupLabel>History</SidebarGroupLabel>
        <SidebarGroupContent>
          <div className="text-zinc-500 h-dvh w-full flex flex-row justify-center items-center text-sm gap-2">
            <InfoIcon />
            <div>Login to save and revisit previous chats!</div>
          </div>
        </SidebarGroupContent>
      </SidebarGroup>
    );
  }

  if (isLoading) {
    return (
      <SidebarGroup>
        <SidebarGroupLabel>History</SidebarGroupLabel>
        <SidebarGroupContent>
          <div className="flex flex-col">
            {[44, 32, 28, 64, 52].map((item) => (
              <div
                key={item}
                className="rounded-md h-8 flex gap-2 px-2 items-center"
              >
                <div
                  className="h-4 rounded-md flex-1 max-w-[--skeleton-width] bg-sidebar-accent-foreground/10"
                  style={
                    {
                      '--skeleton-width': `${item}%`,
                    } as React.CSSProperties
                  }
                />
              </div>
            ))}
          </div>
        </SidebarGroupContent>
      </SidebarGroup>
    );
  }

  if (history?.length === 0) {
    return (
      <SidebarGroup>
        <SidebarGroupLabel>History</SidebarGroupLabel>
        <SidebarGroupContent>
          <SidebarMenu>
            <SidebarMenuItem>
              <SidebarMenuButton>
                <InfoIcon />
                <span>No chats found</span>
              </SidebarMenuButton>
            </SidebarMenuItem>
          </SidebarMenu>
        </SidebarGroupContent>
      </SidebarGroup>
    );
  }

  return (
    <>
      <SidebarGroup>
        <SidebarGroupLabel>History</SidebarGroupLabel>
        <SidebarGroupContent>
          <SidebarMenu>
            {history &&
              history.map((chat) => (
                <SidebarMenuItem key={chat.id}>
                  <SidebarMenuButton asChild isActive={chat.id === id}>
                    <Link
                      href={`/chat/${chat.id}`}
                      onClick={() => setOpenMobile(false)}
                    >
                      <span>{getTitleFromChat(chat)}</span>
                    </Link>
                  </SidebarMenuButton>
                  <DropdownMenu modal={true}>
                    <DropdownMenuTrigger asChild>
                      <SidebarMenuAction
                        className="data-[state=open]:bg-sidebar-accent data-[state=open]:text-sidebar-accent-foreground"
                        showOnHover={chat.id !== id}
                      >
                        <MoreHorizontalIcon />
                        <span className="sr-only">More</span>
                      </SidebarMenuAction>
                    </DropdownMenuTrigger>
                    <DropdownMenuContent side="bottom" align="end">
                      <DropdownMenuItem
                        className="text-destructive focus:bg-destructive/15 focus:text-destructive"
                        onSelect={() => {
                          setDeleteId(chat.id);
                          setShowDeleteDialog(true);
                        }}
                      >
                        <TrashIcon />
                        <span>Delete</span>
                      </DropdownMenuItem>
                    </DropdownMenuContent>
                  </DropdownMenu>
                </SidebarMenuItem>
              ))}
          </SidebarMenu>
        </SidebarGroupContent>
      </SidebarGroup>
      <AlertDialog open={showDeleteDialog} onOpenChange={setShowDeleteDialog}>
        <AlertDialogContent>
          <AlertDialogHeader>
            <AlertDialogTitle>Are you absolutely sure?</AlertDialogTitle>
            <AlertDialogDescription>
              This action cannot be undone. This will permanently delete your
              chat and remove it from our servers.
            </AlertDialogDescription>
          </AlertDialogHeader>
          <AlertDialogFooter>
            <AlertDialogCancel>Cancel</AlertDialogCancel>
            <AlertDialogAction onClick={handleDelete}>
              Continue
            </AlertDialogAction>
          </AlertDialogFooter>
        </AlertDialogContent>
      </AlertDialog>
    </>
  );
}