Handle file errors when saving a macro.

Author: SuuperW

src/BizHawk.Client.EmuHawk/tools/Macros/MacroInput.cs

@@ -289,7 +289,7 @@ private bool SaveMacroAs(MovieZone macro)
 				return false;
 			}
 
-			macro.Save(result);
+			macro.Save(result); // ignore errors: This tool is going to be removed.
 			Config!.RecentMacros.Add(result);
 
 			return true;

src/BizHawk.Client.EmuHawk/tools/Macros/MovieZone.cs

@@ -198,19 +198,25 @@ public void PlaceZone(IMovie movie, Config config)
 			}
 		}
 
-		public void Save(string fileName)
+		public FileWriteResult Save(string fileName)
 		{
 			// Save the controller definition/LogKey
 			// Save the controller name and player count. (Only for the user.)
 			// Save whether or not the macro should use overlay input, and/or replace
-			string[] header = new string[4];
-			header[0] = InputKey;
-			header[1] = _emulator.ControllerDefinition.Name;
-			header[2] = _emulator.ControllerDefinition.PlayerCount.ToString();
-			header[3] = $"{Overlay},{Replace}";
-
-			File.WriteAllLines(fileName, header);
-			File.AppendAllLines(fileName, _log);
+
+			return FileWriter.Write(fileName, (fs) =>
+			{
+				using var writer = new StreamWriter(fs);
+				writer.WriteLine(InputKey);
+				writer.WriteLine(_emulator.ControllerDefinition.Name);
+				writer.WriteLine(_emulator.ControllerDefinition.PlayerCount.ToString());
+				writer.WriteLine($"{Overlay},{Replace}");
+
+				foreach (string line in _log)
+				{
+					writer.WriteLine(line);
+				}
+			});
 		}
 
 		public MovieZone(string fileName, IDialogController dialogController, IEmulator emulator, IMovieSession movieSession, ToolManager tools)

src/BizHawk.Client.EmuHawk/tools/TAStudio/TAStudio.MenuItems.cs

@@ -172,15 +172,25 @@ private void SaveSelectionToMacroMenuItem_Click(object sender, EventArgs e)
 			if (file != null)
 			{
 				var selectionStart = TasView.SelectionStartIndex!.Value;
-				new MovieZone(
+				MovieZone macro = new(
 					Emulator,
 					Tools,
 					MovieSession,
 					start: selectionStart,
-					length: TasView.SelectionEndIndex!.Value - selectionStart + 1)
-					.Save(file.FullName);
+					length: TasView.SelectionEndIndex!.Value - selectionStart + 1);
+				FileWriteResult saveResult = macro.Save(file.FullName);
 
-				Config.RecentMacros.Add(file.FullName);
+				if (saveResult.IsError)
+				{
+					DialogController.ShowMessageBox(
+						$"Failed to save macro.\n{saveResult.UserFriendlyErrorMessage()}\n{saveResult.Exception.Message}",
+						"Error",
+						EMsgBoxIcon.Error);
+				}
+				else
+				{
+					Config.RecentMacros.Add(file.FullName);
+				}
 			}
 		}