feat: 点击 toast 激活原窗口（P1a）

- WindowActivator：ALT 模拟 + AttachThreadInput + SetForegroundWindow 组合技抢前台
- save 抓的前台句柄经 PipeMessage/ToastRequest 一路带到 toast
- 点击 toast 主体激活目标窗口后再关闭
- Win32 互操作用 LibraryImport（AOT 友好）
- 新增 acttest 自测子命令

Notify/App.axaml.cs

@@ -58,6 +58,7 @@ public partial class App : Application
             Message = message.Message,
             InputMode = message.InputMode,
             Sticky = message.Sticky,
+            TargetHwnd = message.TargetHwnd,
         }));
     }
 

Notify/Cli/CliRunner.cs

@@ -52,6 +52,7 @@ public static class CliRunner
             Message = message,
             InputMode = false,
             Sticky = false,
+            TargetHwnd = state?.Hwnd ?? 0,
         });
     }
 
@@ -71,6 +72,7 @@ public static class CliRunner
         }
 
         var (title, message) = Resolve(input);
+        var state = StateStore.Load(input.SessionId);
 
         return SendToHost(new PipeMessage
         {
@@ -79,9 +81,36 @@ public static class CliRunner
             Message = message,
             InputMode = true,
             Sticky = true,
+            TargetHwnd = state?.Hwnd ?? 0,
         });
     }
 
+    // 仅用于自测：acttest <hwnd>，尝试激活指定窗口并把结果写入临时日志
+    public static int ActTest(string[] args)
+    {
+        if (args.Length < 2 || !long.TryParse(args[1], out var h))
+        {
+            return 1;
+        }
+
+        var before = Win32.GetForegroundWindow().ToInt64();
+        var ok = WindowActivator.Activate(new IntPtr(h));
+        var after = Win32.GetForegroundWindow().ToInt64();
+
+        try
+        {
+            System.IO.File.WriteAllText(
+                System.IO.Path.Combine(System.IO.Path.GetTempPath(), "notify-acttest.log"),
+                $"target={h} before={before} after={after} ok={ok}\n");
+        }
+        catch
+        {
+            // 忽略
+        }
+
+        return ok ? 0 : 1;
+    }
+
     // SessionEnd：清理会话状态
     public static int Cleanup()
     {

Notify/Interop/Win32.cs

@@ -7,4 +7,58 @@ internal static partial class Win32
 {
     [LibraryImport("user32.dll")]
     internal static partial IntPtr GetForegroundWindow();
+
+    [LibraryImport("user32.dll")]
+    [return: MarshalAs(UnmanagedType.Bool)]
+    internal static partial bool SetForegroundWindow(IntPtr hWnd);
+
+    [LibraryImport("user32.dll")]
+    [return: MarshalAs(UnmanagedType.Bool)]
+    internal static partial bool AllowSetForegroundWindow(uint dwProcessId);
+
+    [LibraryImport("user32.dll")]
+    [return: MarshalAs(UnmanagedType.Bool)]
+    internal static partial bool AttachThreadInput(uint idAttach, uint idAttachTo, [MarshalAs(UnmanagedType.Bool)] bool fAttach);
+
+    [LibraryImport("user32.dll")]
+    internal static partial uint GetWindowThreadProcessId(IntPtr hWnd, out uint lpdwProcessId);
+
+    [LibraryImport("user32.dll")]
+    [return: MarshalAs(UnmanagedType.Bool)]
+    internal static partial bool BringWindowToTop(IntPtr hWnd);
+
+    [LibraryImport("user32.dll")]
+    [return: MarshalAs(UnmanagedType.Bool)]
+    internal static partial bool SetWindowPos(IntPtr hWnd, IntPtr hWndInsertAfter, int x, int y, int cx, int cy, uint uFlags);
+
+    [LibraryImport("user32.dll")]
+    [return: MarshalAs(UnmanagedType.Bool)]
+    internal static partial bool ShowWindow(IntPtr hWnd, int nCmdShow);
+
+    [LibraryImport("user32.dll")]
+    [return: MarshalAs(UnmanagedType.Bool)]
+    internal static partial bool IsIconic(IntPtr hWnd);
+
+    [LibraryImport("user32.dll")]
+    [return: MarshalAs(UnmanagedType.Bool)]
+    internal static partial bool IsWindow(IntPtr hWnd);
+
+    [LibraryImport("user32.dll")]
+    internal static partial void SwitchToThisWindow(IntPtr hWnd, [MarshalAs(UnmanagedType.Bool)] bool fAltTab);
+
+    [LibraryImport("user32.dll")]
+    internal static partial void keybd_event(byte bVk, byte bScan, uint dwFlags, IntPtr dwExtraInfo);
+
+    [LibraryImport("kernel32.dll")]
+    internal static partial uint GetCurrentThreadId();
+
+    // --- 常量 ---
+    internal const uint ASFW_ANY = 0xFFFFFFFF;
+    internal const int SW_RESTORE = 9;
+    internal const int SW_SHOW = 5;
+    internal const uint SWP_NOSIZE = 0x0001;
+    internal const uint SWP_NOMOVE = 0x0002;
+    internal const uint SWP_SHOWWINDOW = 0x0040;
+    internal const byte VK_MENU = 0x12;
+    internal const uint KEYEVENTF_KEYUP = 0x0002;
 }

Notify/Interop/WindowActivator.cs

@@ -0,0 +1,72 @@
+using System;
+
+namespace Notify.Interop;
+
+/// <summary>
+/// 把目标窗口拉回前台
+///
+/// Windows 限制后台进程抢焦点，这里用一套组合技绕过：ALT 键模拟 +
+/// AttachThreadInput 把当前线程与前台/目标线程的输入队列挂接 +
+/// SetWindowPos/BringWindowToTop/SwitchToThisWindow/SetForegroundWindow 多管齐下
+/// </summary>
+public static class WindowActivator
+{
+    public static bool Activate(IntPtr hwnd)
+    {
+        if (hwnd == IntPtr.Zero || !Win32.IsWindow(hwnd))
+        {
+            return false;
+        }
+
+        try
+        {
+            // 最小化的先还原
+            if (Win32.IsIconic(hwnd))
+            {
+                Win32.ShowWindow(hwnd, Win32.SW_RESTORE);
+            }
+
+            var foreground = Win32.GetForegroundWindow();
+            var curThread = Win32.GetCurrentThreadId();
+            var fgThread = Win32.GetWindowThreadProcessId(foreground, out _);
+            var targetThread = Win32.GetWindowThreadProcessId(hwnd, out _);
+
+            // 模拟一次 ALT 抬起，满足 Windows 的"防焦点抢占"前置条件
+            Win32.keybd_event(Win32.VK_MENU, 0, 0, IntPtr.Zero);
+            Win32.keybd_event(Win32.VK_MENU, 0, Win32.KEYEVENTF_KEYUP, IntPtr.Zero);
+
+            if (fgThread != curThread)
+            {
+                Win32.AttachThreadInput(curThread, fgThread, true);
+            }
+
+            if (targetThread != curThread && targetThread != fgThread)
+            {
+                Win32.AttachThreadInput(curThread, targetThread, true);
+            }
+
+            Win32.AllowSetForegroundWindow(Win32.ASFW_ANY);
+            Win32.SetWindowPos(hwnd, IntPtr.Zero, 0, 0, 0, 0, Win32.SWP_NOMOVE | Win32.SWP_NOSIZE | Win32.SWP_SHOWWINDOW);
+            Win32.BringWindowToTop(hwnd);
+            Win32.SwitchToThisWindow(hwnd, true);
+            Win32.SetForegroundWindow(hwnd);
+            Win32.ShowWindow(hwnd, Win32.SW_SHOW);
+
+            if (targetThread != curThread && targetThread != fgThread)
+            {
+                Win32.AttachThreadInput(curThread, targetThread, false);
+            }
+
+            if (fgThread != curThread)
+            {
+                Win32.AttachThreadInput(curThread, fgThread, false);
+            }
+
+            return Win32.GetForegroundWindow() == hwnd;
+        }
+        catch
+        {
+            return false;
+        }
+    }
+}

Notify/Ipc/PipeMessage.cs

@@ -17,4 +17,7 @@ public sealed class PipeMessage
 
     // 触发该通知的会话 id，便于 Host 后续按会话激活窗口
     public string? SessionId { get; set; }
+
+    // 点击 toast 时要激活的目标窗口句柄，0 表示无
+    public long TargetHwnd { get; set; }
 }

Notify/Models/ToastRequest.cs

@@ -18,4 +18,9 @@ public sealed class ToastRequest
     /// true = 常驻：不自动消失，只能点击 / ✕ 关闭
     /// </summary>
     public bool Sticky { get; init; }
+
+    /// <summary>
+    /// 点击 toast 主体时要激活的窗口句柄，0 表示不激活
+    /// </summary>
+    public long TargetHwnd { get; init; }
 }

Notify/Program.cs

@@ -31,6 +31,7 @@ internal static class Program
             "notify" => CliRunner.Notify(),
             "input" => CliRunner.Input(),
             "cleanup" => CliRunner.Cleanup(),
+            "acttest" => CliRunner.ActTest(args),
             _ => RunHost(args),
         };
     }

Notify/Services/ToastManager.cs

@@ -33,7 +33,7 @@ public sealed class ToastManager
         }
 
         var vm = new ToastViewModel(request);
-        var window = new ToastWindow(vm, settings, request.Sticky);
+        var window = new ToastWindow(vm, settings, request.Sticky, request.TargetHwnd);
         window.Closed += OnToastClosed;
 
         _active.Add(window);

Notify/Views/ToastWindow.axaml.cs

@@ -20,16 +20,18 @@ public partial class ToastWindow : Window
     private readonly ToastSettings _settings;
     private readonly DispatcherTimer _dismissTimer;
     private readonly bool _sticky;
+    private readonly long _targetHwnd;
     private bool _closing;
 
     // 设计器需要的无参构造
-    public ToastWindow() : this(new ToastViewModel(new ToastRequest { Title = "Title", Message = "Message" }), new ToastSettings(), false)
+    public ToastWindow() : this(new ToastViewModel(new ToastRequest { Title = "Title", Message = "Message" }), new ToastSettings(), false, 0)
     {
     }
 
-    public ToastWindow(ToastViewModel vm, ToastSettings settings, bool sticky)
+    public ToastWindow(ToastViewModel vm, ToastSettings settings, bool sticky, long targetHwnd)
     {
         _settings = settings;
+        _targetHwnd = targetHwnd;
         // 常驻：请求显式 Sticky，或全局停留时长 <= 0
         _sticky = sticky || settings.DurationSeconds <= 0;
         InitializeComponent();
@@ -119,9 +121,14 @@ public partial class ToastWindow : Window
 
     private void OnBodyPressed(object? sender, PointerPressedEventArgs e)
     {
-        // 左键点击主体：后续接入"激活原窗口 + 切回标签页"，当前先关闭
+        // 左键点击主体：激活原窗口后关闭
         if (e.GetCurrentPoint(this).Properties.IsLeftButtonPressed)
         {
+            if (_targetHwnd != 0)
+            {
+                Notify.Interop.WindowActivator.Activate(new IntPtr(_targetHwnd));
+            }
+
             BeginClose();
         }
     }