feat: 实现preferences类

src/Core/Core.csproj

@@ -8,6 +8,7 @@
 
     <ItemGroup>
       <PackageReference Include="Dapper" Version="2.1.72" />
+      <PackageReference Include="Newtonsoft.Json" Version="13.0.4" />
       <PackageReference Include="System.Data.SQLite" Version="2.0.3" />
       <PackageReference Include="z440.atl.core" Version="7.13.0" />
     </ItemGroup>

src/Core/Preferences.cs

@@ -0,0 +1,108 @@
+using Newtonsoft.Json;
+
+namespace OCES.Resonance.Core;
+
+/// <summary>
+/// 应用偏好设置，单例模式，负责平台路径解析与 JSON 持久化。
+/// </summary>
+public class Preferences
+{
+    private static readonly Lazy<Preferences> _instance = new(() => new Preferences());
+
+    /// <summary>单例访问入口</summary>
+    public static Preferences Instance
+    {
+        get { return _instance.Value; }
+    }
+
+    /// <summary>数据库文件存放目录</summary>
+    public string DatabasePath { get; set; } = string.Empty;
+
+    /// <summary>偏好设置 JSON 文件的完整路径</summary>
+    public string PreferencesPath { get; set; } = string.Empty;
+
+    /// <summary>
+    /// 私有构造函数 —— 根据运行时平台设置 <see cref="DatabasePath"/> 和 <see cref="PreferencesPath"/>。
+    /// JSON 反序列化时也会调用此构造函数，随后由 JSON 属性覆盖路径值。
+    /// </summary>
+    [JsonConstructor]
+    Preferences()
+    {
+        if (OperatingSystem.IsMacOS())
+        {
+            string home = Environment.GetFolderPath(Environment.SpecialFolder.UserProfile);
+            DatabasePath = Path.Combine(home, "Library", "Application Support", "Resonance", "Databases");
+            PreferencesPath = Path.Combine(home, "Library", "Preferences", "com.oces.Resonance.json");
+        }
+        else if (OperatingSystem.IsWindows())
+        {
+            string localAppData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
+            string roamingAppData = Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData);
+            DatabasePath = Path.Combine(localAppData, "OCES", "Resonance", "Databases");
+            PreferencesPath = Path.Combine(roamingAppData, "OCES", "Resonance", "preferences.json");
+        }
+        else if (OperatingSystem.IsLinux())
+        {
+            string home = Environment.GetFolderPath(Environment.SpecialFolder.UserProfile);
+            string xdgDataHome = Environment.GetEnvironmentVariable("XDG_DATA_HOME")
+                                 ?? Path.Combine(home, ".local", "share");
+            string xdgConfigHome = Environment.GetEnvironmentVariable("XDG_CONFIG_HOME") 
+                                   ?? Path.Combine(home, ".config");
+            DatabasePath = Path.Combine(xdgDataHome, "Resonance", "Databases");
+            PreferencesPath = Path.Combine(xdgConfigHome, "Resonance", "preferences.json");
+        }
+    }
+
+    /// <summary>
+    /// 将传入的 <see cref="Preferences"/> 实例序列化为 JSON 文件，保存到 <see cref="PreferencesPath"/>。
+    /// </summary>
+    /// <param name="preferences">待序列化的偏好设置实例</param>
+    /// <returns>成功返回 true，失败返回 false</returns>
+    public bool Serialize(Preferences preferences)
+    {
+        try
+        {
+            string? directory = Path.GetDirectoryName(PreferencesPath);
+            if (!string.IsNullOrEmpty(directory) && !Directory.Exists(directory))
+            {
+                Directory.CreateDirectory(directory);
+            }
+
+            string json = JsonConvert.SerializeObject(preferences, Formatting.Indented);
+            File.WriteAllText(PreferencesPath, json);
+            return true;
+        }
+        catch
+        {
+            //调用房根据自己的情况，自己处理接到false该怎么办。
+            return false;
+        }
+    }
+
+    /// <summary>
+    /// 从指定路径读取 JSON 文件并反序列化为 <see cref="Preferences"/> 实例。
+    /// </summary>
+    /// <param name="preferencesPath">JSON 文件的完整路径</param>
+    /// <returns>反序列化成功返回 Preferences 实例，失败返回 null</returns>
+    public Preferences? Deserialize(string preferencesPath)
+    {
+        try
+        {
+            if (!File.Exists(preferencesPath))
+            {
+                return null;
+            }
+
+            string json = File.ReadAllText(preferencesPath);
+            JsonSerializerSettings settings = new()
+            {
+                ConstructorHandling = ConstructorHandling.AllowNonPublicDefaultConstructor,
+            };
+            return JsonConvert.DeserializeObject<Preferences>(json, settings);
+        }
+        catch
+        {
+            return null;
+        }
+    }
+}