更新框架

Source/Store.Management.Framework/Services/SettingsServiceBase.cs

@@ -0,0 +1,99 @@
+using System.IO;
+using Newtonsoft.Json;
+using Prism.Mvvm;
+using Store.Management.Framework.Configs;
+
+namespace Store.Management.Framework.Services;
+
+public interface ISettingsServiceBase<T> where T : class
+{
+	T Model { get; }
+	string FilePath { get; }
+	T GetDefaultModel();
+	void LoadSettings();
+	Task LoadSettingsAsync();
+	void SaveSettings();
+	Task SaveSettingsAsync();
+}
+
+/// <summary>
+/// JSON 配置服务。缺失文件保留当前配置，加载失败保留旧模型并抛出异常。
+/// 保存通过同目录临时文件替换目标；模型变更应在所属 UI 线程调用。
+/// </summary>
+public abstract class JsonSettingsServiceBase<T> : BindableBase, ISettingsServiceBase<T> where T : class
+{
+	private readonly SemaphoreSlim _gate = new(1, 1);
+	private T? _model;
+	/// <summary>默认按模型类型名保存到用户配置目录，派生类可覆盖文件名或完整路径。</summary>
+	public virtual string FilePath => FolderConfig.GetSettingsFilePath(typeof(T).Name + ".json");
+	public abstract T GetDefaultModel();
+	public T Model
+	{
+		get => _model ??= GetDefaultModel() ?? throw new InvalidOperationException("默认配置不能为空。");
+		protected set
+		{
+			ArgumentNullException.ThrowIfNull(value);
+			SetProperty(ref _model, value);
+		}
+	}
+
+	public void LoadSettings()
+	{
+		T? loaded = LoadModelAsync().GetAwaiter().GetResult();
+		if (loaded is not null) Model = loaded;
+	}
+	public void SaveSettings() => SaveSettingsAsync().GetAwaiter().GetResult();
+
+	public async Task LoadSettingsAsync()
+	{
+		T? loaded = await LoadModelAsync();
+		if (loaded is not null) Model = loaded;
+	}
+
+	private async Task<T?> LoadModelAsync()
+	{
+		T? loaded = null;
+		await _gate.WaitAsync().ConfigureAwait(false);
+		try
+		{
+			string path = GetFullPath();
+			try
+			{
+				string json = await File.ReadAllTextAsync(path).ConfigureAwait(false);
+				loaded = JsonConvert.DeserializeObject<T>(json)
+					?? throw new JsonSerializationException($"配置文件不能为 null：{path}");
+			}
+			catch (FileNotFoundException) { }
+			catch (DirectoryNotFoundException) { }
+		}
+		finally { _gate.Release(); }
+		return loaded;
+	}
+
+	public async Task SaveSettingsAsync()
+	{
+		// 在首次等待前读取模型，避免在后台线程初始化默认模型。
+		string json = JsonConvert.SerializeObject(Model, Formatting.Indented);
+		await _gate.WaitAsync().ConfigureAwait(false);
+		string? temporaryPath = null;
+		try
+		{
+			string path = GetFullPath();
+			Directory.CreateDirectory(Path.GetDirectoryName(path)!);
+			temporaryPath = path + "." + Guid.NewGuid().ToString("N") + ".tmp";
+			await File.WriteAllTextAsync(temporaryPath, json).ConfigureAwait(false);
+			File.Move(temporaryPath, path, overwrite: true);
+		}
+		finally
+		{
+			try { if (temporaryPath is not null && File.Exists(temporaryPath)) File.Delete(temporaryPath); }
+			finally { _gate.Release(); }
+		}
+	}
+
+	private string GetFullPath()
+	{
+		ArgumentException.ThrowIfNullOrWhiteSpace(FilePath);
+		return Path.GetFullPath(FilePath);
+	}
+}