import { useState } from 'react';
import { useMutation, useQueryClient } from '@tanstack/react-query';
import { useTranslation } from 'react-i18next';
import { useNavigate } from 'react-router';

import { deleteGuild, guildQueryKey, leaveGuild } from '@/api/guilds';
import { instanceQueryKey } from '@/api/instance';
import { myGuildsQueryKey } from '@/api/users';
import { ErrorNotice } from '@/components/ui/ErrorNotice';
import { Modal } from '@/components/ui/Modal';
import { Button } from '@/components/ui/primitives';
import { useSessionStore } from '@/stores/session';
import { SettingsSection } from '@/pages/settings/SettingsSection';

interface GuildDangerSectionProps {
  guildId: string;
  guildName: string;
  /** Владелец не может покинуть сервер — только удалить его. */
  isOwner: boolean;
  /** Администратор инстанса может удалить любой сервер. */
  isInstanceAdmin: boolean;
}

type ConfirmAction = 'leave' | 'delete';

/** «Опасная зона»: выход с сервера и удаление сервера с подтверждением. */
export function GuildDangerSection({
  guildId,
  guildName,
  isOwner,
  isInstanceAdmin,
}: GuildDangerSectionProps) {
  const { t } = useTranslation();
  const navigate = useNavigate();
  const queryClient = useQueryClient();
  const [confirm, setConfirm] = useState<ConfirmAction | null>(null);
  // Последнее действие: пока окно закрывается, тексты не должны «прыгать».
  const [lastAction, setLastAction] = useState<ConfirmAction>('leave');

  const ask = (action: ConfirmAction): void => {
    setLastAction(action);
    setConfirm(action);
  };

  /** После выхода/удаления возвращаемся в приложение и обновляем снапшот. */
  const afterExit = (): void => {
    setConfirm(null);
    useSessionStore.getState().removeGuild(guildId);
    useSessionStore.getState().selectSettingsGuild(null);
    void queryClient.invalidateQueries({ queryKey: myGuildsQueryKey });
    void queryClient.invalidateQueries({ queryKey: instanceQueryKey });
    void queryClient.removeQueries({ queryKey: guildQueryKey(guildId) });
    void navigate('/app', { replace: true });
  };

  const leave = useMutation({
    mutationFn: () => leaveGuild(guildId),
    onSuccess: afterExit,
  });

  const remove = useMutation({
    mutationFn: () => deleteGuild(guildId),
    onSuccess: afterExit,
  });

  const canDelete = isOwner || isInstanceAdmin;
  const pending = leave.isPending || remove.isPending;

  return (
    <SettingsSection
      title={t('settings.servers.danger.title')}
      description={t('settings.servers.danger.description')}
      className="border-danger/40"
    >
      <div className="mt-4 flex flex-col gap-4">
        {isOwner ? (
          <p className="text-sm text-fg-muted">{t('settings.servers.danger.leaveOwnerHint')}</p>
        ) : (
          <div className="flex flex-wrap items-center justify-between gap-3">
            <p className="max-w-md text-sm text-fg-muted">
              {t('settings.servers.danger.leaveHint')}
            </p>
            <Button
              variant="ghost"
              className="border-danger/50 text-danger"
              disabled={pending}
              onClick={() => {
                leave.reset();
                ask('leave');
              }}
            >
              {t('settings.servers.danger.leave')}
            </Button>
          </div>
        )}

        {canDelete ? (
          <div className="flex flex-wrap items-center justify-between gap-3 border-t border-border/40 pt-4">
            <p className="max-w-md text-sm text-fg-muted">
              {t('settings.servers.danger.deleteHint')}
            </p>
            <Button
              variant="ghost"
              className="border-danger/50 text-danger"
              disabled={pending}
              onClick={() => {
                remove.reset();
                ask('delete');
              }}
            >
              {t('settings.servers.danger.delete')}
            </Button>
          </div>
        ) : null}
      </div>

      {leave.isError ? <ErrorNotice className="mt-3" error={leave.error} /> : null}
      {remove.isError ? <ErrorNotice className="mt-3" error={remove.error} /> : null}

      <Modal
        open={confirm !== null}
        title={t(
          lastAction === 'delete'
            ? 'settings.servers.danger.deleteConfirmTitle'
            : 'settings.servers.danger.leaveConfirmTitle',
        )}
        onClose={() => setConfirm(null)}
        footer={
          <>
            <Button variant="ghost" onClick={() => setConfirm(null)}>
              {t('common.cancel')}
            </Button>
            <Button
              disabled={pending}
              onClick={() => {
                if (lastAction === 'delete') {
                  remove.mutate();
                  return;
                }
                leave.mutate();
              }}
            >
              {t(
                lastAction === 'delete'
                  ? 'settings.servers.danger.deleteConfirm'
                  : 'settings.servers.danger.leaveConfirm',
              )}
            </Button>
          </>
        }
      >
        <p className="text-sm text-fg-muted">
          {t(
            lastAction === 'delete'
              ? 'settings.servers.danger.deleteConfirmBody'
              : 'settings.servers.danger.leaveConfirmBody',
            { name: guildName },
          )}
        </p>
      </Modal>
    </SettingsSection>
  );
}