import type { IpRule } from './api';

const MAX_IPS = 200;

/** 从表单生成 IpRule，未选模式或内容为空时返回 null */
export function buildIpRule(mode: '' | 'allow' | 'block', text: string): IpRule | null {
  if (mode !== 'allow' && mode !== 'block') return null;
  const ips = text
    .split(/[\n,;，]+/u)
    .map(s => s.trim())
    .filter(Boolean)
    .slice(0, MAX_IPS);
  if (ips.length === 0) return null;
  return { mode, ips };
}

export function parseIpRuleText(json: string | null | undefined): { mode: '' | 'allow' | 'block'; text: string } {
  if (!json) return { mode: '', text: '' };
  try {
    const r = JSON.parse(json) as IpRule;
    if (r.mode !== 'allow' && r.mode !== 'block') return { mode: '', text: '' };
    return { mode: r.mode, text: (r.ips ?? []).join('\n') };
  } catch {
    return { mode: '', text: '' };
  }
}