Fix 'Sequence contains no elements' bug (#29)

windows-terminal-quake/Native/TerminalProcess.cs

@@ -0,0 +1,110 @@
+using Polly;
+using Polly.Retry;
+using Serilog;
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
+
+namespace WindowsTerminalQuake.Native
+{
+	public static class TerminalProcess
+	{
+		private static readonly RetryPolicy Retry = Policy
+			.Handle<Exception>()
+			.WaitAndRetry(new[]
+				{
+					TimeSpan.FromMilliseconds(25),
+					TimeSpan.FromMilliseconds(50),
+					TimeSpan.FromMilliseconds(100),
+					TimeSpan.FromMilliseconds(250),
+					TimeSpan.FromMilliseconds(500)
+				},
+				onRetry: (ex, t) => Log.Error($"Error creating process: '{ex.Message}'"));
+
+		private static Process? _process;
+
+		private static List<Action> _onExit = new List<Action>();
+
+		private static bool _isExitting;
+
+		public static void OnExit(Action action)
+		{
+			_onExit.Add(action);
+		}
+
+		private static void FireOnExit()
+		{
+			_isExitting = true;
+
+			_onExit.ForEach(a => a());
+		}
+
+		public static Process Get()
+		{
+			return Retry.Execute(() =>
+			{
+				if (_isExitting) return _process!;
+
+				if (_process == null || _process.HasExited)
+				{
+					_process = GetOrCreate();
+				}
+
+				return _process;
+			});
+		}
+
+		private static Process GetOrCreate()
+		{
+			const string existingProcessName = "WindowsTerminal";
+			const string newProcessName = "wt.exe";
+
+			var process = Process.GetProcessesByName(existingProcessName).FirstOrDefault();
+			if (process == null)
+			{
+				process = new Process
+				{
+					StartInfo = new ProcessStartInfo
+					{
+						FileName = newProcessName,
+						WindowStyle = ProcessWindowStyle.Maximized
+					}
+				};
+
+				process.Start();
+				process.WaitForInputIdle();
+
+				// After starting the process, just throw an exception so the process search gets restarted.
+				// The "wt.exe" process does some stuff to ultimately fire up a "WindowsTerminal" process, so we can't actually use the Process instance we just created.
+				throw new Exception($"Started process");
+			}
+
+			// Try the "nice way" of waiting for the process to become ready
+			process.Refresh();
+			process.WaitForInputIdle();
+
+			Log.Information(
+				$"Got process with id '{process.Id}' and name '{process.ProcessName}' and title '{process.MainWindowTitle}'.");
+
+			// Make sure the process has not exited
+			if (process.HasExited) throw new Exception($"Process existing.");
+
+			// Make sure we can access the main window handle
+			// Note: Accessing mainWindowHandle already throws "Process has exited, so the requested information is not available."
+			if (process.MainWindowHandle == IntPtr.Zero) throw new Exception("Main window handle no accessible.");
+
+			// Make sure the process name equals "WindowsTerminal", otherwise WT might still be starting
+			if (process.ProcessName != "WindowsTerminal") throw new Exception("Process name is not 'WindowsTerminal' yet.");
+
+			// This is a way-too-specific check to further ensure the WT process is ready
+			if (process.MainWindowTitle == "DesktopWindowXamlSource")
+				throw new Exception($"Process still has temporary 'DesktopWindowXamlSource' window title.");
+
+			process.EnableRaisingEvents = true;
+			process.Exited += (s, a) => FireOnExit();
+
+			return process;
+		}
+	}
+}

windows-terminal-quake/Program.cs

@@ -1,10 +1,9 @@
-using System;
-using System.Diagnostics;
+using Serilog;
+using System;
 using System.Linq;
 using System.Windows.Forms;
 using WindowsTerminalQuake.Native;
 using WindowsTerminalQuake.UI;
-using Serilog;
 
 namespace WindowsTerminalQuake
 {
@@ -21,18 +20,14 @@ public static void Main(string[] args)
 
 			try
 			{
-				var process = GetOrCreateWindowsTerminalProcess();
-				process.EnableRaisingEvents = true;
-				process.Exited += (sender, e) =>
-				{
-					Close();
-				};
-				_toggler = new Toggler(process);
+				TerminalProcess.OnExit(() => Close());
+
+				_toggler = new Toggler();
 
 				// Transparency
 				Settings.Get(s =>
 				{
-					TransparentWindow.SetTransparent(process, s.Opacity);
+					TransparentWindow.SetTransparent(TerminalProcess.Get(), s.Opacity);
 				});
 
 				var hks = string.Join(" or ", Settings.Instance.Hotkeys.Select(hk => $"{hk.Modifiers}+{hk.Key}"));
@@ -48,43 +43,6 @@ public static void Main(string[] args)
 			}
 		}
 
-		private static Process GetOrCreateWindowsTerminalProcess()
-		{
-			var process = Process.GetProcessesByName("WindowsTerminal").FirstOrDefault();
-
-			if (process == null)
-			{
-				process = new Process
-				{
-					StartInfo = new ProcessStartInfo
-					{
-						FileName = "wt",
-						UseShellExecute = false,
-						RedirectStandardOutput = true,
-						WindowStyle = ProcessWindowStyle.Maximized
-					}
-				};
-				process.Start();
-
-				try
-				{
-					// Note: Accessing mainWindowHandle already throws "Process has exited, so the requested information is not available."
-					if (process.MainWindowHandle == IntPtr.Zero)
-					{
-						throw new Exception("Can not access newly started process.");
-					}
-				}
-				catch (Exception)
-				{
-					process = Process.GetProcessesByName("WindowsTerminal").First();
-					// _process.WaitForInputIdle();
-					process.Refresh();
-				}
-			}
-
-			return process;
-		}
-
 		private static void Close()
 		{
 			_toggler?.Dispose();

windows-terminal-quake/Toggler.cs

@@ -12,22 +12,20 @@ namespace WindowsTerminalQuake
 {
 	public class Toggler : IDisposable
 	{
-		private Process _process;
+		private Process _process => TerminalProcess.Get();
 
 		private readonly List<int> _registeredHotKeys = new List<int>();
 
-		public Toggler(Process process)
+		public Toggler()
 		{
-			_process = process;
-
 			// Hide from taskbar
 			User32.SetWindowLong(_process.MainWindowHandle, User32.GWL_EX_STYLE, (User32.GetWindowLong(_process.MainWindowHandle, User32.GWL_EX_STYLE) | User32.WS_EX_TOOLWINDOW) & ~User32.WS_EX_APPWINDOW);
 
 			User32.Rect rect = default;
-			var ok = User32.GetWindowRect(_process.MainWindowHandle, ref rect);
-			var isOpen = rect.Top >= GetScreenWithCursor().Bounds.Y;
 			User32.ShowWindow(_process.MainWindowHandle, NCmdShow.MAXIMIZE);
 
+			var isOpen = true;
+
 			// Register hotkeys
 			Settings.Get(s =>
 			{