Refactored file attachments (#608)

app/MindWork AI Studio/Chat/ContentImage.cs

@@ -32,7 +32,7 @@ public sealed class ContentImage : IContent, IImageSource
     public List<Source> Sources { get; set; } = [];
 
     /// <inheritdoc />
-    public List<string> FileAttachments { get; set; } = [];
+    public List<FileAttachment> FileAttachments { get; set; } = [];
 
     /// <inheritdoc />
     public Task<ChatThread> CreateFromProviderAsync(IProvider provider, Model chatModel, IContent? lastUserPrompt, ChatThread? chatChatThread, CancellationToken token = default)

app/MindWork AI Studio/Chat/ContentText.cs

@@ -42,7 +42,7 @@ public sealed class ContentText : IContent
     public List<Source> Sources { get; set; } = [];
     
     /// <inheritdoc />
-    public List<string> FileAttachments { get; set; } = [];
+    public List<FileAttachment> FileAttachments { get; set; } = [];
 
     /// <inheritdoc />
     public async Task<ChatThread> CreateFromProviderAsync(IProvider provider, Model chatModel, IContent? lastUserPrompt, ChatThread? chatThread, CancellationToken token = default)
@@ -149,24 +149,24 @@ public sealed class ContentText : IContent
 
     #endregion
 
-    public async Task<string> PrepareContentForAI()
+    public async Task<string> PrepareTextContentForAI()
     {
         var sb = new StringBuilder();
         sb.AppendLine(this.Text);
 
         if(this.FileAttachments.Count > 0)
         {
-            // Filter out files that no longer exist
-            var existingFiles = this.FileAttachments.Where(File.Exists).ToList();
+            // Get the list of existing documents:
+            var existingDocuments = this.FileAttachments.Where(x => x.Type is FileAttachmentType.DOCUMENT && x.Exists).ToList();
 
-            // Log warning for missing files
-            var missingFiles = this.FileAttachments.Except(existingFiles).ToList();
-            if (missingFiles.Count > 0)
-                foreach (var missingFile in missingFiles)
-                    LOGGER.LogWarning("File attachment no longer exists and will be skipped: '{MissingFile}'", missingFile);
-
-            // Only proceed if there are existing files
-            if (existingFiles.Count > 0)
+            // Log warning for missing files:
+            var missingDocuments = this.FileAttachments.Except(existingDocuments).Where(x => x.Type is FileAttachmentType.DOCUMENT).ToList();
+            if (missingDocuments.Count > 0)
+                foreach (var missingDocument in missingDocuments)
+                    LOGGER.LogWarning("File attachment no longer exists and will be skipped: '{MissingDocument}'.", missingDocument.FilePath);
+            
+            // Only proceed if there are existing, allowed documents:
+            if (existingDocuments.Count > 0)
             {
                 // Check Pandoc availability once before processing file attachments
                 var pandocState = await Pandoc.CheckAvailabilityAsync(Program.RUST_SERVICE, showMessages: true, showSuccessMessage: false);
@@ -179,14 +179,20 @@ public sealed class ContentText : IContent
                 {
                     sb.AppendLine();
                     sb.AppendLine("The following files are attached to this message:");
-                    foreach(var file in existingFiles)
+                    foreach(var document in existingDocuments)
                     {
+                        if (document.IsForbidden)
+                        {
+                            LOGGER.LogWarning("File attachment '{FilePath}' has a forbidden file type and will be skipped.", document.FilePath);
+                            continue;
+                        }
+                        
                         sb.AppendLine();
                         sb.AppendLine("---------------------------------------");
-                        sb.AppendLine($"File path: {file}");
+                        sb.AppendLine($"File path: {document.FilePath}");
                         sb.AppendLine("File content:");
                         sb.AppendLine("````");
-                        sb.AppendLine(await Program.RUST_SERVICE.ReadArbitraryFileData(file, int.MaxValue));
+                        sb.AppendLine(await Program.RUST_SERVICE.ReadArbitraryFileData(document.FilePath, int.MaxValue));
                         sb.AppendLine("````");
                     }
                 }

app/MindWork AI Studio/Chat/FileAttachment.cs

@@ -0,0 +1,71 @@
+using AIStudio.Tools.Rust;
+
+namespace AIStudio.Chat;
+
+/// <summary>
+/// Represents an immutable file attachment with details about its type, name, path, and size.
+/// </summary>
+/// <param name="Type">The type of the file attachment.</param>
+/// <param name="FileName">The name of the file, including extension.</param>
+/// <param name="FilePath">The full path to the file, including the filename and extension.</param>
+/// <param name="FileSizeBytes">The size of the file in bytes.</param>
+public readonly record struct FileAttachment(FileAttachmentType Type, string FileName, string FilePath, long FileSizeBytes)
+{
+    /// <summary>
+    /// Gets a value indicating whether the file still exists on the file system.
+    /// </summary>
+    public bool Exists => File.Exists(this.FilePath);
+
+    /// <summary>
+    /// Gets a value indicating whether the file type is forbidden and should not be attached.
+    /// </summary>
+    public bool IsForbidden => this.Type == FileAttachmentType.FORBIDDEN;
+
+    /// <summary>
+    /// Gets a value indicating whether the file type is valid and allowed to be attached.
+    /// </summary>
+    public bool IsValid => this.Type != FileAttachmentType.FORBIDDEN;
+
+    /// <summary>
+    /// Creates a FileAttachment from a file path by automatically determining the type,
+    /// extracting the filename, and reading the file size.
+    /// </summary>
+    /// <param name="filePath">The full path to the file.</param>
+    /// <returns>A FileAttachment instance with populated properties.</returns>
+    public static FileAttachment FromPath(string filePath)
+    {
+        var fileName = Path.GetFileName(filePath);
+        var fileSize = File.Exists(filePath) ? new FileInfo(filePath).Length : 0;
+        var type = DetermineFileType(filePath);
+
+        return new FileAttachment(type, fileName, filePath, fileSize);
+    }
+
+    /// <summary>
+    /// Determines the file attachment type based on the file extension.
+    /// Uses centrally defined file type filters from <see cref="FileTypeFilter"/>.
+    /// </summary>
+    /// <param name="filePath">The file path to analyze.</param>
+    /// <returns>The corresponding FileAttachmentType.</returns>
+    private static FileAttachmentType DetermineFileType(string filePath)
+    {
+        var extension = Path.GetExtension(filePath).TrimStart('.').ToLowerInvariant();
+
+        // Check if it's an image file:
+        if (FileTypeFilter.AllImages.FilterExtensions.Contains(extension))
+            return FileAttachmentType.IMAGE;
+
+        // Check if it's an audio file:
+        if (FileTypeFilter.AllAudio.FilterExtensions.Contains(extension))
+            return FileAttachmentType.AUDIO;
+
+        // Check if it's an allowed document file (PDF, Text, or Office):
+        if (FileTypeFilter.PDF.FilterExtensions.Contains(extension) ||
+            FileTypeFilter.Text.FilterExtensions.Contains(extension) ||
+            FileTypeFilter.AllOffice.FilterExtensions.Contains(extension))
+            return FileAttachmentType.DOCUMENT;
+
+        // All other file types are forbidden:
+        return FileAttachmentType.FORBIDDEN;
+    }
+}

app/MindWork AI Studio/Chat/FileAttachmentType.cs

@@ -0,0 +1,27 @@
+namespace AIStudio.Chat;
+
+/// <summary>
+/// Represents different types of file attachments.
+/// </summary>
+public enum FileAttachmentType
+{
+    /// <summary>
+    /// Document file types, such as .pdf, .docx, .txt, etc.
+    /// </summary>
+    DOCUMENT,
+
+    /// <summary>
+    /// All image file types, such as .jpg, .png, .gif, etc.
+    /// </summary>
+    IMAGE,
+
+    /// <summary>
+    /// All audio file types, such as .mp3, .wav, .aac, etc.
+    /// </summary>
+    AUDIO,
+
+    /// <summary>
+    /// Forbidden file types that should not be attached, such as executables.
+    /// </summary>
+    FORBIDDEN,
+}

app/MindWork AI Studio/Chat/IContent.cs

@@ -50,10 +50,10 @@ public interface IContent
 
     /// <summary>
     /// Represents a collection of file attachments associated with the content.
-    /// This property contains a list of file paths that are appended
+    /// This property contains a list of file attachments that are appended
     /// to the content to provide additional context or resources.
     /// </summary>
-    public List<string> FileAttachments { get; set; }
+    public List<FileAttachment> FileAttachments { get; set; }
     
     /// <summary>
     /// Uses the provider to create the content.