import 'dart:convert';
import 'dart:io';

import 'package:path/path.dart' as path;

/// 文件操作工具类
class FileHelper {
  /// 私有构造函数，防止实例化
  FileHelper._();

  /// 读取 JSON 文件并解析
  static Map<String, dynamic> readJsonFile(String filePath) {
    final file = File(filePath);

    if (!file.existsSync()) {
      throw FileNotFoundException('文件不存在: $filePath');
    }

    try {
      final content = file.readAsStringSync();
      return json.decode(content) as Map<String, dynamic>;
    } on FormatException catch (e) {
      throw FileParseException('JSON 解析错误: ${e.message}');
    }
  }

  /// 写入文件内容
  ///
  /// 如果目录不存在，会自动创建
  static void writeFile(String filePath, String content) {
    final file = File(filePath);
    final directory = file.parent;

    // 确保目录存在
    if (!directory.existsSync()) {
      directory.createSync(recursive: true);
    }

    file.writeAsStringSync(content);
  }

  /// 检查文件是否存在
  static bool fileExists(String filePath) {
    return File(filePath).existsSync();
  }

  /// 获取相对于工作目录的绝对路径
  static String resolvePropertyPath(String relativePath, {String? workingDir}) {
    final directory = workingDir ?? Directory.current.path;
    if (path.isAbsolute(relativePath)) {
      return relativePath;
    }
    return path.join(directory, relativePath);
  }

  /// 获取文件的目录路径
  static String getDirectoryPath(String filePath) {
    return path.dirname(filePath);
  }

  /// 获取文件名（不含扩展名）
  static String getFileNameWithoutExtension(String filePath) {
    return path.basenameWithoutExtension(filePath);
  }

  /// 获取文件名（含扩展名）
  static String getFileName(String filePath) {
    return path.basename(filePath);
  }
}

/// 文件未找到异常
class FileNotFoundException implements Exception {
  FileNotFoundException(this.message);

  final String message;

  @override
  String toString() => 'FileNotFoundException: $message';
}

/// 文件解析异常
class FileParseException implements Exception {
  FileParseException(this.message);

  final String message;

  @override
  String toString() => 'FileParseException: $message';
}