feat: Java有关重构

CONTRIBUTING.md

@@ -30,7 +30,8 @@
 | PathList | 游戏文件夹列表 | list(string) |
 | Path_$name | 版本路径 | string |
 | Game_$name | 版本列表 | list(string) |
-| java | Java路径 | string |
+| javaSelectedPath | 所选Java路径 | string |
+| javaRuntimes | Java运行时列表（以JSON格式存储） | string |
 
 离线账号配置 offline_account_$name list(string)
 | 序号 | 值 |

lib/function/java/java_service.dart

@@ -0,0 +1,147 @@
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:fml/function/java/java_utils.dart';
+import 'package:fml/function/java/models/java_info.dart';
+import 'package:fml/function/java/models/java_runtime.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+class JavaService {
+  JavaService._();
+
+  static List<JavaRuntime> _javaRuntimes = [];
+  static List<JavaRuntime> get javaRuntimes => _javaRuntimes;
+
+  static String _javaSelectedPath = '';
+  static String get javaSelectedPath => _javaSelectedPath;
+
+  static JavaInfo? _systemDefaultJavaInfo;
+  static JavaInfo? get systemDefaultJavaInfo => _systemDefaultJavaInfo;
+
+  static late final Future<void> initFuture;
+
+  static Future<void> init() async {
+    final futures = await Future.wait([
+      JavaUtils.getSystemDefaultJavaInfo(),
+      SharedPreferences.getInstance(),
+    ]);
+
+    _systemDefaultJavaInfo = futures[0] as JavaInfo?;
+    SharedPreferences prefs = futures[1] as SharedPreferences;
+
+    final cachedJson = prefs.getString('javaRuntimes') ?? '';
+    final systemJavaInfo = _systemDefaultJavaInfo;
+    final List<String> validPaths = [];
+
+    _javaRuntimes = [];
+
+    late final List<JavaRuntime> cachedRuntimes;
+
+    if (cachedJson.isEmpty) {
+      // 初次打开/缓存为空，直接执行搜索并写入
+      _javaRuntimes = await JavaUtils.searchPotentialJavaExecutables();
+      updateJavaRuntimes(_javaRuntimes, prefs);
+    } else {
+      cachedRuntimes = await readJavaRuntimesFromPrefs(cachedJson);
+
+      // 遍历缓存的列表
+      for (final javaRuntime in cachedRuntimes) {
+        // 仅检测对应文件是否存在
+        if (await File(javaRuntime.executable).exists()) {
+          _javaRuntimes.add(javaRuntime);
+          validPaths.add(javaRuntime.executable);
+        }
+      }
+    }
+
+    // 缓存内java列表出现了变化，再次写入SharedPreferences
+    if (cachedJson.isNotEmpty && validPaths.length != cachedRuntimes.length) {
+      updateJavaRuntimes(_javaRuntimes, prefs);
+    }
+
+    // 缓存内路径全部失效，搜索Java
+    if (_javaRuntimes.isEmpty) {
+      _javaRuntimes = await JavaUtils.searchPotentialJavaExecutables();
+
+      updateJavaRuntimes(_javaRuntimes, prefs);
+    }
+
+    /// 处理_currentJavaPath
+    _javaSelectedPath = prefs.getString('javaSelectedPath') ?? '';
+
+    // 若不存在/为空，设置为系统java，若系统java也不存在，设置为扫描到的第一个JavaRuntime
+    if (_javaSelectedPath.isEmpty) {
+      if (systemJavaInfo != null) {
+        _javaSelectedPath = systemJavaInfo.path;
+      } else if (javaRuntimes.isNotEmpty) {
+        _javaSelectedPath = _javaRuntimes.first.executable;
+      }
+
+      prefs.setString('javaSelectedPath', _javaSelectedPath);
+    } else {
+      // 缓存的java已无效，重复上方逻辑
+      final info = await JavaUtils.probeJavaExecutable(_javaSelectedPath);
+
+      if (info == null) {
+        if (systemJavaInfo != null) {
+          _javaSelectedPath = systemJavaInfo.path;
+        } else if (javaRuntimes.isNotEmpty) {
+          _javaSelectedPath = _javaRuntimes.first.executable;
+        }
+
+        prefs.setString('javaSelectedPath', _javaSelectedPath);
+      }
+    }
+  }
+
+  ///
+  /// 从JSON字符串反序列化出存储的JavaRuntimes列表
+  ///
+  static Future<List<JavaRuntime>> readJavaRuntimesFromPrefs(
+    String input,
+  ) async {
+    final List<dynamic> decoded = jsonDecode(input);
+
+    return decoded
+        .map((e) => JavaRuntime.fromJson(e as Map<String, dynamic>))
+        .toList();
+  }
+
+  ///
+  /// 更新[_javaRuntimes]并写入
+  ///
+  static Future<void> updateJavaRuntimes(
+    List<JavaRuntime> newList, [
+    SharedPreferences? prefsIn,
+  ]) async {
+    _javaRuntimes = newList;
+
+    // 如果外部传了prefs就用外部的，否则内部获取实例
+    final prefs = prefsIn ?? await SharedPreferences.getInstance();
+
+    final String jsonString = jsonEncode(newList);
+
+    await prefs.setString('javaRuntimes', jsonString);
+  }
+
+  ///
+  /// 更新[_javaSelectedPath]并写入
+  ///
+  static Future<void> updateJavaSelectedPath(String newPath) async {
+    // 检查路径
+    if (newPath == _javaSelectedPath) return;
+
+    final newFile = File(newPath);
+
+    if (!newFile.existsSync()) {
+      throw ArgumentError('路径不存在: $newPath');
+    }
+
+    // 更新路径并写入
+    _javaSelectedPath = newPath;
+
+    final prefs = await SharedPreferences.getInstance();
+
+    await prefs.setString('javaSelectedPath', _javaSelectedPath);
+  }
+}