import 'dart:convert';

/// 与 uniApp 端 utils/crypto.js 完全一致的密码混淆算法（XOR + Base64）。
/// 注意：仅防明文存储，非强加密。
const String _secretKey = 'QIANGBAO_AI_JIZHANG_2024';

String encryptPassword(String password) {
  if (password.isEmpty) return '';
  final chars = password.codeUnits;
  final keyUnits = _secretKey.codeUnits;
  final encrypted = String.fromCharCodes([
    for (var i = 0; i < chars.length; i++) chars[i] ^ keyUnits[i % keyUnits.length],
  ]);
  return base64Encode(utf8.encode(encrypted));
}

String decryptPassword(String encrypted) {
  if (encrypted.isEmpty) return '';
  try {
    final decoded = utf8.decode(base64Decode(encrypted));
    final chars = decoded.codeUnits;
    final keyUnits = _secretKey.codeUnits;
    return String.fromCharCodes([
      for (var i = 0; i < chars.length; i++) chars[i] ^ keyUnits[i % keyUnits.length],
    ]);
  } catch (_) {
    return '';
  }
}