[GUI] add game library watcher & remove rescan button (#678)

2026-08-01 15:39:47 +08:00 · 2026-07-28 17:09:22 +03:00
parent a3130e30ff
commit b07e4f2bc6
23 changed files with 655 additions and 77 deletions
@@ -0,0 +1,147 @@
+// Copyright (C) 2026 SharpEmu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+namespace SharpEmu.GUI;
+
+/// <summary>
+/// Watches configured game folders and collapses filesystem bursts into one
+/// library refresh request
+/// </summary>
+internal sealed class GameLibraryWatcher : IDisposable
+{
+    private static readonly TimeSpan DefaultDebounceInterval = TimeSpan.FromMilliseconds(600);
+
+    private readonly object _sync = new();
+    private readonly TimeSpan _debounceInterval;
+    private readonly List<FileSystemWatcher> _watchers = [];
+    private Timer? _debounceTimer;
+    private bool _disposed;
+
+    internal GameLibraryWatcher(TimeSpan? debounceInterval = null)
+    {
+        _debounceInterval = debounceInterval ?? DefaultDebounceInterval;
+    }
+
+    public event EventHandler? RefreshRequested;
+
+    /// <summary>
+    /// Replaces the watched roots with the current configured game folders
+    /// </summary>
+    public void Watch(IReadOnlyList<string> folders)
+    {
+        lock (_sync)
+        {
+            ObjectDisposedException.ThrowIf(_disposed, this);
+
+            foreach (var watcher in _watchers)
+            {
+                watcher.Dispose();
+            }
+
+            _watchers.Clear();
+            _debounceTimer?.Change(Timeout.InfiniteTimeSpan, Timeout.InfiniteTimeSpan);
+            foreach (var folder in folders.Distinct(GameLibraryPath.Comparer))
+            {
+                if (string.IsNullOrWhiteSpace(folder) || !Directory.Exists(folder))
+                {
+                    continue;
+                }
+
+                try
+                {
+                    var watcher = new FileSystemWatcher(folder)
+                    {
+                        IncludeSubdirectories = true,
+                        NotifyFilter = NotifyFilters.FileName
+                                       | NotifyFilters.DirectoryName
+                                       | NotifyFilters.LastWrite
+                                       | NotifyFilters.Size,
+                    };
+                    watcher.Created += OnFileSystemChanged;
+                    watcher.Changed += OnFileSystemChanged;
+                    watcher.Deleted += OnFileSystemChanged;
+                    watcher.Renamed += OnFileSystemChanged;
+                    watcher.Error += OnWatcherError;
+                    watcher.EnableRaisingEvents = true;
+                    _watchers.Add(watcher);
+                }
+                catch (Exception exception) when (
+                    exception is ArgumentException
+                        or IOException
+                        or UnauthorizedAccessException)
+                {
+                    Console.Error.WriteLine(
+                        $"[GUI][WARN] Could not watch game folder '{folder}': {exception.Message}");
+                }
+            }
+        }
+    }
+
+    private void OnFileSystemChanged(object sender, FileSystemEventArgs args)
+        => ScheduleRefresh();
+
+    private void OnWatcherError(object sender, ErrorEventArgs args)
+    {
+        Console.Error.WriteLine(
+            $"[GUI][WARN] Game library watcher reported an error: {args.GetException().Message}");
+        ScheduleRefresh();
+    }
+
+    private void ScheduleRefresh()
+    {
+        lock (_sync)
+        {
+            if (_disposed)
+            {
+                return;
+            }
+
+            if (_debounceTimer is null)
+            {
+                _debounceTimer = new Timer(
+                    static state => ((GameLibraryWatcher)state!).RaiseRefreshRequested(),
+                    this,
+                    _debounceInterval,
+                    Timeout.InfiniteTimeSpan);
+            }
+            else
+            {
+                _debounceTimer.Change(_debounceInterval, Timeout.InfiniteTimeSpan);
+            }
+        }
+    }
+
+    private void RaiseRefreshRequested()
+    {
+        lock (_sync)
+        {
+            if (_disposed)
+            {
+                return;
+            }
+        }
+
+        RefreshRequested?.Invoke(this, EventArgs.Empty);
+    }
+
+    public void Dispose()
+    {
+        lock (_sync)
+        {
+            if (_disposed)
+            {
+                return;
+            }
+
+            _disposed = true;
+            _debounceTimer?.Dispose();
+            _debounceTimer = null;
+            foreach (var watcher in _watchers)
+            {
+                watcher.Dispose();
+            }
+
+            _watchers.Clear();
+        }
+    }
+}