more file operations

src/SharpIDE.Application/Features/Analysis/RoslynAnalysis.cs

@@ -749,6 +749,17 @@ public class RoslynAnalysis
 
 		var project = _workspace!.CurrentSolution.Projects.Single(s => s.FilePath == ((IChildSharpIdeNode)fileModel).GetNearestProjectNode()!.FilePath);
 
+		var existingDocument = fileModel switch
+		{
+			{ IsRazorFile: true } => project.AdditionalDocuments.SingleOrDefault(s => s.FilePath == fileModel.Path),
+			{ IsCsharpFile: true } => project.Documents.SingleOrDefault(s => s.FilePath == fileModel.Path),
+			_ => throw new InvalidOperationException("AddDocument failed: File is not a workspace file")
+		};
+		if (existingDocument is not null)
+		{
+			throw new InvalidOperationException($"AddDocument failed: Document '{fileModel.Path}' already exists in workspace");
+		}
+
 		var sourceText = SourceText.From(content, Encoding.UTF8);
 
 		var newSolution = fileModel switch
@@ -760,4 +771,29 @@ public class RoslynAnalysis
 
 		_workspace.TryApplyChanges(newSolution);
 	}
+
+	public async Task RemoveDocument(SharpIdeFile fileModel)
+	{
+		using var _ = SharpIdeOtel.Source.StartActivity($"{nameof(RoslynAnalysis)}.{nameof(AddDocument)}");
+		await _solutionLoadedTcs.Task;
+		Guard.Against.Null(fileModel, nameof(fileModel));
+
+		var project = _workspace!.CurrentSolution.Projects.Single(s => s.FilePath == ((IChildSharpIdeNode)fileModel).GetNearestProjectNode()!.FilePath);
+
+		var document = fileModel switch
+		{
+			{ IsRazorFile: true } => project.AdditionalDocuments.Single(s => s.FilePath == fileModel.Path),
+			{ IsCsharpFile: true } => project.Documents.Single(s => s.FilePath == fileModel.Path),
+			_ => throw new InvalidOperationException("UpdateDocument failed: File is not in workspace")
+		};
+
+		var newSolution = fileModel switch
+		{
+			{ IsRazorFile: true } => _workspace.CurrentSolution.RemoveAdditionalDocument(document.Id),
+			{ IsCsharpFile: true } => _workspace.CurrentSolution.RemoveDocument(document.Id),
+			_ => throw new InvalidOperationException("AddDocument failed: File is not in workspace")
+		};
+
+		_workspace.TryApplyChanges(newSolution);
+	}
 }

src/SharpIDE.Application/Features/FileWatching/FileChangedService.cs

@@ -32,6 +32,14 @@ public class FileChangedService(RoslynAnalysis roslynAnalysis, IdeOpenTabsFileMa
 		// TODO: handle csproj added
 	}
 
+	public async Task SharpIdeFileRemoved(SharpIdeFile file)
+	{
+		if (file.IsRoslynWorkspaceFile)
+		{
+			await HandleWorkspaceFileRemoved(file);
+		}
+	}
+
 	// All file changes should go via this service
 	public async Task SharpIdeFileChanged(SharpIdeFile file, string newContents, FileChangeType changeType)
 	{
@@ -106,4 +114,15 @@ public class FileChangedService(RoslynAnalysis roslynAnalysis, IdeOpenTabsFileMa
 		GlobalEvents.Instance.SolutionAltered.InvokeParallelFireAndForget();
 		await _roslynAnalysis.UpdateSolutionDiagnostics(newCts.Token);
 	}
+
+	private async Task HandleWorkspaceFileRemoved(SharpIdeFile file)
+	{
+		var newCts = new CancellationTokenSource();
+		var oldCts = Interlocked.Exchange(ref _updateSolutionDiagnosticsCts, newCts);
+		await oldCts.CancelAsync();
+		oldCts.Dispose();
+		await _roslynAnalysis.RemoveDocument(file);
+		GlobalEvents.Instance.SolutionAltered.InvokeParallelFireAndForget();
+		await _roslynAnalysis.UpdateSolutionDiagnostics(newCts.Token);
+	}
 }

src/SharpIDE.Application/Features/FileWatching/SharpIdeSolutionModificationService.cs

@@ -1,21 +1,27 @@
-using SharpIDE.Application.Features.SolutionDiscovery;
+using System.Collections.Concurrent;
+using Microsoft.CodeAnalysis;
+using SharpIDE.Application.Features.SolutionDiscovery;
 using SharpIDE.Application.Features.SolutionDiscovery.VsPersistence;
 
 namespace SharpIDE.Application.Features.FileWatching;
 
 /// Does not do any file system operations, only modifies the in-memory solution model
-public class SharpIdeSolutionModificationService
+public class SharpIdeSolutionModificationService(FileChangedService fileChangedService)
 {
+	private readonly FileChangedService _fileChangedService = fileChangedService;
+
 	public SharpIdeSolutionModel SolutionModel { get; set; } = null!;
 
 	/// The directory must already exist on disk
 	public async Task<SharpIdeFolder> AddDirectory(SharpIdeFolder parentFolder, string directoryName)
 	{
-		// Passing [] to allFiles and allFolders, as we assume that a brand new folder has no subfolders or files yet
 		var addedDirectoryPath = Path.Combine(parentFolder.Path, directoryName);
-		var sharpIdeFolder = new SharpIdeFolder(new DirectoryInfo(addedDirectoryPath), parentFolder, [], []);
+		var allFiles = new ConcurrentBag<SharpIdeFile>();
+		var allFolders = new ConcurrentBag<SharpIdeFolder>();
+		var sharpIdeFolder = new SharpIdeFolder(new DirectoryInfo(addedDirectoryPath), parentFolder, allFiles, allFolders);
 		parentFolder.Folders.Add(sharpIdeFolder);
-		SolutionModel.AllFolders.Add(sharpIdeFolder);
+		SolutionModel.AllFolders.AddRange((IEnumerable<SharpIdeFolder>)[sharpIdeFolder, ..allFolders]);
+		SolutionModel.AllFiles.AddRange(allFiles);
 		return sharpIdeFolder;
 	}
 
@@ -23,6 +29,30 @@ public class SharpIdeSolutionModificationService
 	{
 		var parentFolderOrProject = (IFolderOrProject)folder.Parent;
 		parentFolderOrProject.Folders.Remove(folder);
-		SolutionModel.AllFolders.Remove(folder);
+
+		// Also remove all child files and folders from SolutionModel.AllFiles and AllFolders
+		var foldersToRemove = new List<SharpIdeFolder>();
+
+		var stack = new Stack<SharpIdeFolder>();
+		stack.Push(folder);
+		while (stack.Count > 0)
+		{
+			var current = stack.Pop();
+			foldersToRemove.Add(current);
+
+			foreach (var subfolder in current.Folders)
+			{
+				stack.Push(subfolder);
+			}
+		}
+
+		var filesToRemove = foldersToRemove.SelectMany(f => f.Files).ToList();
+
+		SolutionModel.AllFiles.RemoveRange(filesToRemove);
+		SolutionModel.AllFolders.RemoveRange(foldersToRemove);
+		foreach (var file in filesToRemove)
+		{
+			await _fileChangedService.SharpIdeFileRemoved(file);
+		}
 	}
 }