// ignore_for_file: constant_identifier_names

import 'dart:io';
import 'dart:typed_data';

import 'package:hgdj/extension/extensions.dart';
import 'package:hgdj/hj_utils/text_util.dart';
import 'package:hgdj/tools_base/debug_log.dart';

const KB_SIZE = 1024;
const MB_SIZE = 1024 * KB_SIZE;
const GB_SIZE = 1024 * MB_SIZE;

/// 文件相关的公共处理
class FileUtil {
  /// 计算切片个数
  static int getPatchCount(int fileLen) {
    final cutSize = getPatchSize(fileLen);
    return (fileLen + cutSize - 1) ~/ cutSize;
  }

  /// 根据文件长度计算切片大小
  static int getPatchSize(int fileLen) {
    if (fileLen < MB_SIZE) return MB_SIZE;
    return 2 * MB_SIZE;
  }

  /// 文件是否存在
  static bool isFileExist(String path) {
    return TextUtil.isNotEmpty(path) && File(path).existsSync();
  }

  /// 获取 file 从 offset 之后到 blockSize 的数据块
  /// [offset]    起始偏移位置
  /// [blockSize] 分块大小
  /// [file]      文件
  static Future<Uint8List> getFileBlock(
      int offset, int blockSize, File file) async {
    RandomAccessFile? accessFile;
    try {
      accessFile = await file.open();
      await accessFile.setPosition(offset);
      debugLog('offset:$offset blocksize:$blockSize');
      return await accessFile.read(blockSize);
    } on Exception {
      return Uint8List(0);
    } finally {
      accessFile?.close();
    }
  }

  /// 获取文件长度
  static int getFileSize(String path) {
    if (!isFileExist(path)) return 0;
    return File(path).lengthSync();
  }

  /// 获取文件的格式化大小
  static String byteFmt(int size) {
    if (size > GB_SIZE) {
      return '${(size / GB_SIZE).toStringAsFixed(1)}GB';
    } else if (size > MB_SIZE) {
      return '${(size / MB_SIZE).toStringAsFixed(1)}MB';
    } else {
      return '${(size / KB_SIZE).toStringAsFixed(1)}KB';
    }
  }

  /// 获取文件名带后缀
  /// 支持 url/uri/file/abspath
  static String getName(String absPath) {
    if (TextUtil.isEmpty(absPath)) return absPath;
    absPath = Uri.parse(absPath).path;
    final start = absPath.lastIndexOf('/');
    if (start <= 0 || start == absPath.length - 1) {
      return absPath;
    }
    return absPath.substring(start + 1);
  }

  /// 获取文件名不带后缀
  static String getNamePrefix(String absPath) {
    final name = getName(absPath);
    if (TextUtil.isEmpty(name)) return name;
    final ar = name.split('.');
    if (ar.empty()) return name;
    return ar[0];
  }

  /// 获取文件名后缀 (fileExtension)
  static String getNameSuffix(String absPath) {
    final name = getName(absPath);
    if (TextUtil.isEmpty(name)) return name;
    final ar = name.split('.');
    if (ar.empty()) return name;
    if (ar.length < 2) return ar[0];
    return ar.last;
  }
}