// lib/services/code_parser.dart
class CodeParser {
  static final _zongpaiRegex = RegExp(
    r'^\d{2}(B|C|T)\d+$|^\d{2}(BW|CW)\d{4}$',
  );
  static final _locationRegex = RegExp(
    r'^[A-Z0-9]+-[A-Z0-9]+-[A-Z0-9]+$',
  );
  static final _transitRegex = RegExp(
    r'^TRANS-',
  );

  static ParseResult parse(String code) {
    final trimmed = code.trim();
    if (trimmed.isEmpty) {
      return ParseResult(type: CodeType.invalid, value: code);
    }
    final normalized = trimmed.toUpperCase();
    if (_transitRegex.hasMatch(normalized)) {
      return ParseResult(type: CodeType.locationTransit, value: normalized);
    }
    if (_zongpaiRegex.hasMatch(normalized)) {
      return ParseResult(type: CodeType.zongpaiNo, value: normalized);
    }
    if (_locationRegex.hasMatch(normalized)) {
      return ParseResult(type: CodeType.locationNormal, value: normalized);
    }
    return ParseResult(type: CodeType.invalid, value: code);
  }

  static bool isLocation(CodeType type) =>
      type == CodeType.locationNormal || type == CodeType.locationTransit;
}

enum CodeType { zongpaiNo, locationNormal, locationTransit, invalid }

class ParseResult {
  final CodeType type;
  final String value;
  ParseResult({required this.type, required this.value});
}