Paste submitted text via clipboard

WirelessTextSyncer.Windows/Services/KeyboardInjectionService.cs

@@ -13,6 +13,7 @@ public sealed class KeyboardInjectionService : IKeyboardInjectionService
     private const ushort VirtualKeyBack = 0x08;
     private const ushort VirtualKeyControl = 0x11;
     private const ushort VirtualKeyReturn = 0x0D;
+    private const ushort VirtualKeyV = 0x56;
     private static readonly IntPtr EnglishKeyboardLayout = LoadKeyboardLayout("00000409", KlfActivate);
 
     public void InsertText(string text)
@@ -22,7 +23,13 @@ public sealed class KeyboardInjectionService : IKeyboardInjectionService
             return;
         }
 
-        AppLogger.Info($"Injecting text length: {text.Length}");
+        AppLogger.Info($"Pasting text length: {text.Length}");
+        PasteTextViaClipboard(text);
+    }
+
+    private static void TypeTextWithSendInput(string text)
+    {
+        AppLogger.Info($"Falling back to SendInput text length: {text.Length}");
         using var keyboardLayoutScope = KeyboardLayoutScope.SwitchForegroundWindowToEnglish();
         foreach (var character in text)
         {
@@ -32,6 +39,68 @@ public sealed class KeyboardInjectionService : IKeyboardInjectionService
         }
     }
 
+    private static void PasteTextViaClipboard(string text)
+    {
+        Exception? failure = null;
+        var thread = new Thread(() =>
+        {
+            try
+            {
+                PasteTextOnStaThread(text);
+            }
+            catch (Exception ex)
+            {
+                failure = ex;
+            }
+        });
+
+        thread.SetApartmentState(ApartmentState.STA);
+        thread.Start();
+        thread.Join();
+
+        if (failure is not null)
+        {
+            AppLogger.Error("Clipboard paste failed.", failure);
+            TypeTextWithSendInput(text);
+        }
+    }
+
+    private static void PasteTextOnStaThread(string text)
+    {
+        var hadText = Clipboard.ContainsText(TextDataFormat.UnicodeText);
+        var previousText = hadText ? Clipboard.GetText(TextDataFormat.UnicodeText) : null;
+
+        try
+        {
+            Clipboard.SetText(text, TextDataFormat.UnicodeText);
+            Thread.Sleep(30);
+            SendModifiedKey(VirtualKeyControl, VirtualKeyV);
+            Thread.Sleep(150);
+        }
+        finally
+        {
+            RestoreClipboardText(hadText, previousText);
+        }
+    }
+
+    private static void RestoreClipboardText(bool hadText, string? previousText)
+    {
+        try
+        {
+            if (hadText && previousText is not null)
+            {
+                Clipboard.SetText(previousText, TextDataFormat.UnicodeText);
+                return;
+            }
+
+            Clipboard.Clear();
+        }
+        catch (Exception ex)
+        {
+            AppLogger.Error("Failed to restore clipboard text.", ex);
+        }
+    }
+
     public void ReplaceFocusedText(string text)
     {
         AppLogger.Info($"Replacing focused text length: {text.Length}");