fix: wire up file picker change handler for attach button

PolyPilot.Tests/TestStubs.cs

@@ -108,7 +108,7 @@ public Task RequestHistoryAsync(string sessionName, int? limit = null, Cancellat
             SessionHistories[sessionName] = new List<ChatMessage>(existing);
         return Task.CompletedTask;
     }
-    public Task SendMessageAsync(string sessionName, string message, string? agentMode = null, CancellationToken ct = default)
+    public Task SendMessageAsync(string sessionName, string message, string? agentMode = null, List<ImageAttachment>? imageAttachments = null, CancellationToken ct = default)
     {
         if (ThrowOnSend)
             throw new InvalidOperationException("Not connected to server");

PolyPilot/Components/Pages/Dashboard.razor

@@ -3058,8 +3058,36 @@
 
     private async Task TriggerAttach(string sessionName)
     {
-        var fileId = $"file-{sessionName.Replace(" ", "-")}";
-        await JS.InvokeVoidAsync("clickElement", fileId);
+        if (PlatformHelper.IsMobile)
+        {
+            // On mobile, use MAUI MediaPicker for the native photo picker experience.
+            // Falls back to FilePicker if MediaPicker is unavailable.
+            try
+            {
+                var photo = await MediaPicker.PickPhotoAsync(new MediaPickerOptions
+                {
+                    Title = "Select an image"
+                });
+                if (photo == null) return;
+
+                using var stream = await photo.OpenReadAsync();
+                using var ms = new MemoryStream();
+                await stream.CopyToAsync(ms);
+                var base64 = Convert.ToBase64String(ms.ToArray());
+                var ext = Path.GetExtension(photo.FileName)?.TrimStart('.') ?? "png";
+                var inputId = $"input-{sessionName.Replace(" ", "-")}";
+                await JsImagePasted(base64, photo.FileName, ext, inputId);
+            }
+            catch (Exception ex)
+            {
+                Console.WriteLine($"MediaPicker error: {ex.Message}");
+            }
+        }
+        else
+        {
+            var fileId = $"file-{sessionName.Replace(" ", "-")}";
+            await JS.InvokeVoidAsync("clickElement", fileId);
+        }
     }
 
     private void TouchMru(string sessionName)

PolyPilot/Models/BridgeMessages.cs

@@ -259,6 +259,15 @@ public class SendMessagePayload
     public string Message { get; set; } = "";
     /// <summary>SDK agent mode: "interactive", "plan", "autopilot", "shell". Null = default (interactive).</summary>
     public string? AgentMode { get; set; }
+    /// <summary>Image attachments encoded as base64 for transmission over the bridge.</summary>
+    public List<ImageAttachment>? ImageAttachments { get; set; }
+}
+
+/// <summary>Base64-encoded image for bridge transmission.</summary>
+public class ImageAttachment
+{
+    public string Base64Data { get; set; } = "";
+    public string FileName { get; set; } = "image.png";
 }
 
 public class CreateSessionPayload

PolyPilot/Services/CopilotService.cs

@@ -3348,7 +3348,28 @@ public async Task<string> SendPromptAsync(string sessionName, string prompt, Lis
             OnStateChanged?.Invoke();
             try
             {
-                await _bridgeClient.SendMessageAsync(sessionName, prompt, agentMode, cancellationToken);
+                // Encode images as base64 for bridge transmission
+                List<ImageAttachment>? imageAttachments = null;
+                if (imagePaths != null && imagePaths.Count > 0)
+                {
+                    imageAttachments = new();
+                    foreach (var path in imagePaths)
+                    {
+                        if (!File.Exists(path)) continue;
+                        try
+                        {
+                            var bytes = await File.ReadAllBytesAsync(path, cancellationToken);
+                            imageAttachments.Add(new ImageAttachment
+                            {
+                                Base64Data = Convert.ToBase64String(bytes),
+                                FileName = Path.GetFileName(path)
+                            });
+                        }
+                        catch (Exception ex) { Debug($"Failed to encode image '{path}': {ex.Message}"); }
+                    }
+                    if (imageAttachments.Count == 0) imageAttachments = null;
+                }
+                await _bridgeClient.SendMessageAsync(sessionName, prompt, agentMode, imageAttachments, cancellationToken);
             }
             catch
             {

PolyPilot/Services/IWsBridgeClient.cs

@@ -44,7 +44,7 @@ public interface IWsBridgeClient
     void AbortForReconnect();
     Task RequestSessionsAsync(CancellationToken ct = default);
     Task RequestHistoryAsync(string sessionName, int? limit = null, CancellationToken ct = default);
-    Task SendMessageAsync(string sessionName, string message, string? agentMode = null, CancellationToken ct = default);
+    Task SendMessageAsync(string sessionName, string message, string? agentMode = null, List<ImageAttachment>? imageAttachments = null, CancellationToken ct = default);
     Task CreateSessionAsync(string name, string? model = null, string? workingDirectory = null, CancellationToken ct = default);
     Task SwitchSessionAsync(string name, CancellationToken ct = default);
     Task QueueMessageAsync(string sessionName, string message, string? agentMode = null, CancellationToken ct = default);

PolyPilot/Services/WsBridgeClient.cs

@@ -350,9 +350,9 @@ public async Task RequestHistoryAsync(string sessionName, int? limit = null, Can
         await SendAsync(BridgeMessage.Create(BridgeMessageTypes.GetHistory,
             new GetHistoryPayload { SessionName = sessionName, Limit = limit }), ct);
 
-    public async Task SendMessageAsync(string sessionName, string message, string? agentMode = null, CancellationToken ct = default) =>
+    public async Task SendMessageAsync(string sessionName, string message, string? agentMode = null, List<ImageAttachment>? imageAttachments = null, CancellationToken ct = default) =>
         await SendAsync(BridgeMessage.Create(BridgeMessageTypes.SendMessage,
-            new SendMessagePayload { SessionName = sessionName, Message = message, AgentMode = agentMode }), ct);
+            new SendMessagePayload { SessionName = sessionName, Message = message, AgentMode = agentMode, ImageAttachments = imageAttachments }), ct);
 
     public async Task CreateSessionAsync(string name, string? model = null, string? workingDirectory = null, CancellationToken ct = default) =>
         await SendAsync(BridgeMessage.Create(BridgeMessageTypes.CreateSession,

PolyPilot/Services/WsBridgeServer.cs

@@ -337,7 +337,7 @@ public async Task DrainPendingPromptsAsync()
     /// Dispatch a bridge prompt with orchestrator routing on the UI thread.
     /// Shared by both the live send_message handler and the drain replay loop.
     /// </summary>
-    private async Task DispatchBridgePromptAsync(string sessionName, string message, string? agentMode, CancellationToken ct = default)
+    private async Task DispatchBridgePromptAsync(string sessionName, string message, string? agentMode, List<string>? imagePaths = null, CancellationToken ct = default)
     {
         try
         {
@@ -354,7 +354,7 @@ private async Task DispatchBridgePromptAsync(string sessionName, string message,
                 }
                 else
                 {
-                    await _copilot.SendPromptAsync(sessionName, message, cancellationToken: ct, agentMode: agentMode);
+                    await _copilot.SendPromptAsync(sessionName, message, imagePaths, cancellationToken: ct, agentMode: agentMode);
                 }
             });
         }
@@ -871,9 +871,9 @@ await SendToClientAsync(clientId, ws,
 
                 messageBuffer.Append(Encoding.UTF8.GetString(buffer, 0, result.Count));
 
-                if (messageBuffer.Length > 256 * 1024)
+                if (messageBuffer.Length > 16 * 1024 * 1024)
                 {
-                    try { await ws.CloseAsync(WebSocketCloseStatus.MessageTooBig, "Message exceeds 256KB limit", CancellationToken.None); } catch { }
+                    try { await ws.CloseAsync(WebSocketCloseStatus.MessageTooBig, "Message exceeds 16MB limit", CancellationToken.None); } catch { }
                     break; // guard against unbounded frames
                 }
 
@@ -927,12 +927,33 @@ await SendToClientAsync(clientId, ws,
 
                 case BridgeMessageTypes.SendMessage:
                     var sendReq = msg.GetPayload<SendMessagePayload>();
-                    if (sendReq != null && !string.IsNullOrWhiteSpace(sendReq.SessionName) && !string.IsNullOrWhiteSpace(sendReq.Message))
+                    if (sendReq != null && !string.IsNullOrWhiteSpace(sendReq.SessionName) && (!string.IsNullOrWhiteSpace(sendReq.Message) || sendReq.ImageAttachments is { Count: > 0 }))
                     {
                         BridgeLog($"[BRIDGE] Client sending message to '{sendReq.SessionName}'");
-                        // Fire-and-forget: don't block the client message loop waiting for the full response.
-                        // SendPromptAsync awaits ResponseCompletion (minutes). Responses stream back via events.
-                        // Blocking here prevents the client from sending abort, switch, or other commands.
+
+                        // Decode any image attachments from base64 to temp files
+                        List<string>? sendImagePaths = null;
+                        if (sendReq.ImageAttachments is { Count: > 0 })
+                        {
+                            var tempDir = Path.Combine(Path.GetTempPath(), "PolyPilot-images");
+                            Directory.CreateDirectory(tempDir);
+                            sendImagePaths = new();
+                            foreach (var att in sendReq.ImageAttachments)
+                            {
+                                try
+                                {
+                                    var ext = Path.GetExtension(att.FileName);
+                                    if (string.IsNullOrEmpty(ext)) ext = ".png";
+                                    var tempPath = Path.Combine(tempDir, $"{Guid.NewGuid()}{ext}");
+                                    await File.WriteAllBytesAsync(tempPath, Convert.FromBase64String(att.Base64Data), ct);
+                                    sendImagePaths.Add(tempPath);
+                                }
+                                catch (Exception ex) { BridgeLog($"[BRIDGE] Failed to decode image '{att.FileName}': {ex.Message}"); }
+                            }
+                            if (sendImagePaths.Count == 0) sendImagePaths = null;
+                            else BridgeLog($"[BRIDGE] Decoded {sendImagePaths.Count} image attachment(s) for '{sendReq.SessionName}'");
+                        }
+
                         var sendSession = sendReq.SessionName;
                         var sendMessage = sendReq.Message;
                         var sendAgentMode = sendReq.AgentMode;
@@ -948,8 +969,15 @@ await SendToClientAsync(clientId, ws,
                         // Dispatch with orchestrator routing on the UI thread (fire-and-forget).
                         _ = Task.Run(async () =>
                         {
-                            try { await DispatchBridgePromptAsync(sendSession, sendMessage, sendAgentMode, ct); }
+                            try { await DispatchBridgePromptAsync(sendSession, sendMessage, sendAgentMode, sendImagePaths, ct); }
                             catch (Exception ex) { BridgeLog($"[BRIDGE] SendPromptAsync error for '{sendSession}': {ex.Message}"); }
+                            finally
+                            {
+                                // Clean up temp image files after send completes
+                                if (sendImagePaths != null)
+                                    foreach (var p in sendImagePaths)
+                                        try { File.Delete(p); } catch { }
+                            }
                         });
                     }
                     break;

PolyPilot/wwwroot/index.html

@@ -120,6 +120,33 @@
             }
         }, true);
 
+        // File picker change handler — reads selected images and sends to Blazor.
+        // Covers the attach button on all platforms (especially mobile where
+        // paste/drag-drop aren't available).
+        document.addEventListener('change', function(e) {
+            if (e.target.type !== 'file' || !e.target.id.startsWith('file-')) return;
+            if (!window.__dashRef) return;
+            var files = e.target.files;
+            if (!files) return;
+            // Derive the input ID from the file input ID (file-X → input-X)
+            var inputId = 'input-' + e.target.id.substring(5);
+            for (var i = 0; i < files.length; i++) {
+                if (!files[i].type.startsWith('image/')) continue;
+                (function(f) {
+                    var reader = new FileReader();
+                    reader.onload = function() {
+                        var base64 = reader.result.split(',')[1];
+                        var ext = (f.name && f.name.includes('.')) ? f.name.split('.').pop() : 'png';
+                        var name = f.name || ('attached-image.' + ext);
+                        window.__dashRef.invokeMethodAsync('JsImagePasted', base64, name, ext, inputId);
+                    };
+                    reader.readAsDataURL(f);
+                })(files[i]);
+            }
+            // Reset so the same file can be re-selected
+            e.target.value = '';
+        });
+
         // Global image drop handler for chat input areas
         document.addEventListener('dragover', function(e) {
             var zone = e.target.closest && (e.target.closest('.input-area') || e.target.closest('.card-input'));