feat: 启动时创建 .wpfhw 目录，持久化设置并缓存项目图标

.gitignore

@@ -14,4 +14,7 @@ wpfhw/obj/
 
 # 系统文件
 Thumbs.db
-.DS_Store
+.DS_Store
+
+# 运行时数据（设置、图片缓存）
+.wpfhw/

wpfhw/App.xaml.cs

@@ -6,9 +6,9 @@ public partial class App : System.Windows.Application
     {
         protected override void OnStartup(StartupEventArgs e)
         {
+            AppStorage.Initialize();
             base.OnStartup(e);
 
-            // 显示启动画面
             var splash = new SplashScreen();
             splash.Show();
         }

wpfhw/AppSettings.cs

@@ -0,0 +1,54 @@
+using System.IO;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace wpfhw;
+
+public class AppSettings
+{
+    private static readonly JsonSerializerOptions JsonOptions = new()
+    {
+        WriteIndented = true,
+        PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
+        DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull
+    };
+
+    public string DownloadPath { get; set; } = "";
+    public string LastProjectType { get; set; } = "mod";
+    public double WindowWidth { get; set; } = 1080;
+    public double WindowHeight { get; set; } = 720;
+
+    public static AppSettings Load()
+    {
+        AppStorage.Initialize();
+
+        try
+        {
+            if (File.Exists(AppStorage.SettingsFile))
+            {
+                string json = File.ReadAllText(AppStorage.SettingsFile);
+                var loaded = JsonSerializer.Deserialize<AppSettings>(json, JsonOptions);
+                if (loaded != null) return loaded;
+            }
+        }
+        catch
+        {
+        }
+
+        return new AppSettings();
+    }
+
+    public void Save()
+    {
+        AppStorage.Initialize();
+
+        try
+        {
+            string json = JsonSerializer.Serialize(this, JsonOptions);
+            File.WriteAllText(AppStorage.SettingsFile, json);
+        }
+        catch
+        {
+        }
+    }
+}

wpfhw/AppStorage.cs

@@ -0,0 +1,29 @@
+using System.IO;
+
+namespace wpfhw;
+
+public static class AppStorage
+{
+    public static string RootDirectory { get; private set; } = "";
+    public static string SettingsFile { get; private set; } = "";
+    public static string CacheDirectory { get; private set; } = "";
+    public static string IconCacheDirectory { get; private set; } = "";
+
+    private static bool _initialized;
+
+    public static void Initialize()
+    {
+        if (_initialized) return;
+
+        RootDirectory = Path.Combine(AppContext.BaseDirectory, ".wpfhw");
+        SettingsFile = Path.Combine(RootDirectory, "settings.json");
+        CacheDirectory = Path.Combine(RootDirectory, "cache");
+        IconCacheDirectory = Path.Combine(CacheDirectory, "icons");
+
+        Directory.CreateDirectory(RootDirectory);
+        Directory.CreateDirectory(CacheDirectory);
+        Directory.CreateDirectory(IconCacheDirectory);
+
+        _initialized = true;
+    }
+}

wpfhw/IconCache.cs

@@ -0,0 +1,93 @@
+using System.Collections.Concurrent;
+using System.IO;
+using System.Net.Http;
+using System.Security.Cryptography;
+using System.Text;
+
+namespace wpfhw;
+
+public static class IconCache
+{
+    private static readonly ConcurrentDictionary<string, Task<string>> InFlight = new(StringComparer.OrdinalIgnoreCase);
+
+    public static string? TryGetLocalPath(string? url)
+    {
+        if (!IsRemoteUrl(url)) return null;
+
+        AppStorage.Initialize();
+        string path = GetCachePath(url!);
+        return File.Exists(path) && new FileInfo(path).Length > 0 ? path : null;
+    }
+
+    public static Task<string> GetLocalPathAsync(string url, HttpClient http, CancellationToken ct)
+    {
+        string? cached = TryGetLocalPath(url);
+        if (cached != null) return Task.FromResult(cached);
+
+        return InFlight.GetOrAdd(url, u => DownloadAsync(u, http, ct));
+    }
+
+    private static async Task<string> DownloadAsync(string url, HttpClient http, CancellationToken ct)
+    {
+        AppStorage.Initialize();
+        string path = GetCachePath(url);
+        string temp = path + "." + Guid.NewGuid().ToString("N") + ".tmp";
+
+        try
+        {
+            if (File.Exists(path) && new FileInfo(path).Length > 0)
+                return path;
+
+            using var response = await http.GetAsync(url, HttpCompletionOption.ResponseHeadersRead, ct);
+            response.EnsureSuccessStatusCode();
+
+            await using (var remote = await response.Content.ReadAsStreamAsync(ct))
+            await using (var local = new FileStream(temp, FileMode.Create, FileAccess.Write, FileShare.None, 8192, true))
+            {
+                await remote.CopyToAsync(local, ct);
+            }
+
+            File.Move(temp, path, overwrite: true);
+            return path;
+        }
+        catch
+        {
+            try { if (File.Exists(temp)) File.Delete(temp); } catch { }
+            throw;
+        }
+        finally
+        {
+            InFlight.TryRemove(url, out _);
+        }
+    }
+
+    public static bool IsRemoteUrl(string? url)
+    {
+        if (string.IsNullOrWhiteSpace(url)) return false;
+        return url.StartsWith("http://", StringComparison.OrdinalIgnoreCase)
+            || url.StartsWith("https://", StringComparison.OrdinalIgnoreCase);
+    }
+
+    private static string GetCachePath(string url)
+    {
+        string hash = Convert.ToHexString(SHA256.HashData(Encoding.UTF8.GetBytes(url))).ToLowerInvariant();
+        string ext = GetExtension(url);
+        return Path.Combine(AppStorage.IconCacheDirectory, hash + ext);
+    }
+
+    private static string GetExtension(string url)
+    {
+        try
+        {
+            var uri = new Uri(url);
+            string ext = Path.GetExtension(uri.AbsolutePath);
+            if (ext is ".png" or ".jpg" or ".jpeg" or ".webp" or ".gif" or ".bmp" or ".ico")
+                return ext.ToLowerInvariant();
+        }
+        catch
+        {
+        }
+
+        return ".png";
+    }
+}

wpfhw/MainWindow.xaml.cs

@@ -32,6 +32,7 @@ public partial class MainWindow : Window
     };
 
     private readonly HttpClient _httpClient;
+    private readonly AppSettings _settings;
     private ModSearchHit? _selectedMod;
     private List<ModVersion> _currentVersions = new();
     private string _currentGameVer = "";
@@ -54,6 +55,7 @@ public partial class MainWindow : Window
     private readonly Dictionary<string, ModTranslation> _pendingByEnglish = new(StringComparer.OrdinalIgnoreCase);
 
     private static readonly HashSet<string> LoaderTypes = new() { "mod", "modpack" };
+    private static readonly HashSet<string> ProjectTypes = new() { "mod", "resourcepack", "shader", "datapack", "modpack" };
 
     public MainWindow()
     {
@@ -64,14 +66,25 @@ public MainWindow()
         _httpClient.DefaultRequestHeaders.UserAgent.ParseAdd(
             "ModDownloader/1.0 (haodi0302@qq.com; Windows)");
 
-        _currentProjectType = "mod";
-        _downloadPath = Environment.GetFolderPath(Environment.SpecialFolder.Desktop);
+        _settings = AppSettings.Load();
+        _currentProjectType = ProjectTypes.Contains(_settings.LastProjectType)
+            ? _settings.LastProjectType
+            : "mod";
+        _downloadPath = !string.IsNullOrWhiteSpace(_settings.DownloadPath) && Directory.Exists(_settings.DownloadPath)
+            ? _settings.DownloadPath
+            : Environment.GetFolderPath(Environment.SpecialFolder.Desktop);
 
-        UpdateNavStyle(navMod);
+        if (_settings.WindowWidth >= 640) Width = _settings.WindowWidth;
+        if (_settings.WindowHeight >= 480) Height = _settings.WindowHeight;
+
+        UpdateNavStyle(GetNavButton(_currentProjectType));
         UpdateLoaderVisibility();
+        UpdateSearchPlaceholder();
+        SaveSettings();
 
-        this.Closed += (s, e) =>
+        Closed += (_, _) =>
         {
+            SaveSettings();
             _downloadCts?.Cancel();
             _downloadCts?.Dispose();
             _searchCts?.Cancel();
@@ -80,6 +93,53 @@ public MainWindow()
         };
     }
 
+    private Button GetNavButton(string projectType) => projectType switch
+    {
+        "resourcepack" => navResource,
+        "shader" => navShader,
+        "datapack" => navData,
+        "modpack" => navPack,
+        _ => navMod
+    };
+
+    private void SaveSettings()
+    {
+        _settings.DownloadPath = _downloadPath;
+        _settings.LastProjectType = _currentProjectType;
+        _settings.WindowWidth = Width;
+        _settings.WindowHeight = Height;
+        _settings.Save();
+    }
+
+    private string ResolveIconUrl(string url)
+    {
+        if (!IconCache.IsRemoteUrl(url)) return url;
+
+        string? local = IconCache.TryGetLocalPath(url);
+        if (local != null)
+            return new Uri(local).AbsoluteUri;
+
+        _ = CacheIconInBackground(url);
+        return url;
+    }
+
+    private async Task CacheIconInBackground(string url)
+    {
+        try
+        {
+            await IconCache.GetLocalPathAsync(url, _httpClient, CancellationToken.None);
+        }
+        catch
+        {
+        }
+    }
+
+    private ModSearchHit WithCachedIcon(ModSearchHit hit)
+    {
+        hit.IconUrl = ResolveIconUrl(hit.IconUrl);
+        return hit;
+    }
+
     private bool HasLoaders() => LoaderTypes.Contains(_currentProjectType);
 
     private void UpdateLoaderVisibility()
@@ -312,7 +372,7 @@ private async Task SearchModrinthByEnglishNames(List<MCModSearchHit> mcHits, Can
                             MatchEnglishName = mc.EnglishName
                         };
 
-                        lstModResult.Items.Add(ApplyTranslation(hit));
+                        lstModResult.Items.Add(WithCachedIcon(ApplyTranslation(hit)));
                         _totalHits++;
                     }
                 }
@@ -381,7 +441,7 @@ private async Task DoModrinthSearch(string keyword, CancellationToken ct)
                 foreach (var m in searchResult.Hits)
                 {
                     TryMatchPendingByEnglish(m);
-                    lstModResult.Items.Add(ApplyTranslation(m));
+                    lstModResult.Items.Add(WithCachedIcon(ApplyTranslation(m)));
                 }
                 txtStatusMsg.Text = $"找到 {_totalHits} 个结果，第 {_currentOffset / PageSize + 1} 页（中译仅在通过MC百科路径搜索时应用）";
             }
@@ -710,6 +770,7 @@ private void BtnBrowseDownloadPath_Click(object sender, RoutedEventArgs e)
         {
             _downloadPath = dialog.FolderName;
             txtDownloadPath.Text = _downloadPath;
+            SaveSettings();
         }
     }