Handle missing file attachments in message processing (#587)

Author: SommerEngineering

app/MindWork AI Studio/Chat/ContentText.cs

@@ -156,29 +156,43 @@ public async Task<string> PrepareContentForAI()
 
         if(this.FileAttachments.Count > 0)
         {
-            // Check Pandoc availability once before processing file attachments
-            var pandocState = await Pandoc.CheckAvailabilityAsync(Program.RUST_SERVICE, showMessages: true, showSuccessMessage: false);
-
-            if (!pandocState.IsAvailable)
-                LOGGER.LogWarning("File attachments could not be processed because Pandoc is not available.");
-            else if (!pandocState.CheckWasSuccessful)
-                LOGGER.LogWarning("File attachments could not be processed because the Pandoc version check failed.");
-            else
+            // Filter out files that no longer exist
+            var existingFiles = this.FileAttachments.Where(File.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)
             {
-                sb.AppendLine();
-                sb.AppendLine("The following files are attached to this message:");
-                foreach(var file in this.FileAttachments)
+                // Check Pandoc availability once before processing file attachments
+                var pandocState = await Pandoc.CheckAvailabilityAsync(Program.RUST_SERVICE, showMessages: true, showSuccessMessage: false);
+
+                if (!pandocState.IsAvailable)
+                    LOGGER.LogWarning("File attachments could not be processed because Pandoc is not available.");
+                else if (!pandocState.CheckWasSuccessful)
+                    LOGGER.LogWarning("File attachments could not be processed because the Pandoc version check failed.");
+                else
                 {
                     sb.AppendLine();
-                    sb.AppendLine("---------------------------------------");
-                    sb.AppendLine($"File path: {file}");
-                    sb.AppendLine("File content:");
-                    sb.AppendLine("````");
-                    sb.AppendLine(await Program.RUST_SERVICE.ReadArbitraryFileData(file, int.MaxValue));
-                    sb.AppendLine("````");
+                    sb.AppendLine("The following files are attached to this message:");
+                    foreach(var file in existingFiles)
+                    {
+                        sb.AppendLine();
+                        sb.AppendLine("---------------------------------------");
+                        sb.AppendLine($"File path: {file}");
+                        sb.AppendLine("File content:");
+                        sb.AppendLine("````");
+                        sb.AppendLine(await Program.RUST_SERVICE.ReadArbitraryFileData(file, int.MaxValue));
+                        sb.AppendLine("````");
+                    }
                 }
             }
         }
+        
         return sb.ToString();
     }