Add support for multiple file attachments in message composer

src/Decho/Models/StagedFile.cs

@@ -0,0 +1,3 @@
+namespace Decho.Models;
+
+public sealed record StagedFile(string FilePath, string FileName);

src/Decho/Services/ConnectionService.cs

@@ -95,6 +95,57 @@ public sealed class ConnectionService : IDisposable
         await entry.Manager.SendMessageAsync(channelName, content);
     }
 
+    public async Task SendMessageWithAttachmentsAsync(string serverUrl, string channelName, string content, IReadOnlyList<string> filePaths, string? size = null)
+    {
+        if (!_connections.TryGetValue(serverUrl, out ServerConnection? entry))
+        {
+            throw new InvalidOperationException("Not connected to server");
+        }
+
+        entry.Manager.RoomKeys.TryGetKey(channelName, out byte[]? roomKey);
+        List<OutgoingAttachment> attachments = new List<OutgoingAttachment>(filePaths.Count);
+
+        foreach (string filePath in filePaths)
+        {
+            string fileName = Path.GetFileName(filePath);
+            OutgoingAttachment attachment;
+
+            if (roomKey is not null && roomKey.Length > 0)
+            {
+                byte[] bytes = await File.ReadAllBytesAsync(filePath);
+                string declaredKind;
+                string? preview = null;
+
+                await using (MemoryStream ms = new MemoryStream(bytes))
+                {
+                    if (FileValidationHelper.IsValidImage(ms))
+                    {
+                        declaredKind = "image";
+                        (int w, int h) = ImageToAsciiService.GetDimensions(size);
+                        ms.Position = 0;
+                        preview = RoomCrypto.EncryptText(new ImageToAsciiService().ConvertToAscii(ms, w, h), roomKey);
+                    }
+                    else
+                    {
+                        declaredKind = FileValidationHelper.IsAudioFile(fileName) ? "audio" : "file";
+                    }
+                }
+
+                byte[] encryptedBlob = RoomCrypto.EncryptBytes(bytes, roomKey);
+                attachment = new OutgoingAttachment(new MemoryStream(encryptedBlob), fileName, declaredKind, preview);
+            }
+            else
+            {
+                byte[] bytes = await File.ReadAllBytesAsync(filePath);
+                attachment = new OutgoingAttachment(new MemoryStream(bytes), fileName);
+            }
+
+            attachments.Add(attachment);
+        }
+
+        _ = await entry.ApiClient.SendMessageWithAttachmentsAsync(channelName, content, attachments, size);
+    }
+
     public async Task<ChannelDto?> CreateChannelAsync(string serverUrl, string name, string? topic, bool isPublic, string? password = null)
     {
         if (!_connections.TryGetValue(serverUrl, out ServerConnection? entry))

src/Decho/ViewModels/MainWindowViewModel.cs

@@ -56,7 +56,6 @@ public sealed class MainWindowViewModel : ViewModelBase
 
         Chat.Composer.SendRequested += HandleSendRequested;
         Chat.Composer.CommandRequested += HandleCommandAsync;
-        Chat.Composer.FileUploadRequested += HandleFileUploadRequested;
         Chat.LoadMoreRequested += HandleLoadMoreRequested;
 
         WireCommandHandlerEvents();
@@ -707,13 +706,32 @@ public sealed class MainWindowViewModel : ViewModelBase
         return result.Message;
     }
 
-    private void HandleSendRequested(string serverUrl, string text)
+    private void HandleSendRequested(string serverUrl, string text, IReadOnlyList<string> filePaths)
     {
         if (string.IsNullOrEmpty(Chat.CurrentChannelName))
         {
             return;
         }
 
+        if (filePaths.Count > 0)
+        {
+            _ = Task.Run(async () =>
+            {
+                try
+                {
+                    await ConnectionService.SendMessageWithAttachmentsAsync(serverUrl, Chat.CurrentChannelName, text, filePaths);
+                    Avalonia.Threading.Dispatcher.UIThread.Post(() =>
+                        StatusText = "Message sent");
+                }
+                catch (Exception ex)
+                {
+                    Avalonia.Threading.Dispatcher.UIThread.Post(() =>
+                        StatusText = $"Send failed: {ex.Message}");
+                }
+            });
+            return;
+        }
+
         if (_commandHandler.IsCommand(text))
         {
             _ = HandleCommandAsync(text);
@@ -736,29 +754,6 @@ public sealed class MainWindowViewModel : ViewModelBase
         });
     }
 
-    private void HandleFileUploadRequested(string serverUrl, string filePath)
-    {
-        if (string.IsNullOrEmpty(Chat.CurrentChannelName))
-        {
-            return;
-        }
-
-        _ = Task.Run(async () =>
-        {
-            try
-            {
-                await ConnectionService.UploadFileAsync(serverUrl, Chat.CurrentChannelName, filePath, null);
-                Avalonia.Threading.Dispatcher.UIThread.Post(() =>
-                    StatusText = "File uploaded");
-            }
-            catch (Exception ex)
-            {
-                Avalonia.Threading.Dispatcher.UIThread.Post(() =>
-                    StatusText = $"Upload failed: {ex.Message}");
-            }
-        });
-    }
-
     private async Task HandleCreateChannelRequested(ServerViewModel server)
     {
         if (_mainWindow is null)

src/Decho/ViewModels/MessageComposerViewModel.cs

@@ -1,4 +1,7 @@
+using Decho.Models;
+
 using EchoHub.Client.Commands;
+using EchoHub.Core.Constants;
 
 using System.Collections.ObjectModel;
 using System.Reactive;
@@ -7,16 +10,24 @@ namespace Decho.ViewModels;
 
 public sealed class MessageComposerViewModel : ViewModelBase
 {
-    public event Action<string, string>? SendRequested;
+    public event Action<string, string, IReadOnlyList<string>>? SendRequested;
 
     public event Func<string, Task<string?>>? CommandRequested;
 
-    public event Action<string, string>? FileUploadRequested;
-
     private readonly ObservableCollection<UserViewModel> _onlineUsers = [];
     private readonly ObservableCollection<string> _channelNames = [];
     private CommandHandler? _commandHandler;
 
+    public ObservableCollection<StagedFile> StagedFiles { get; } = [];
+
+    public bool HasStagedFiles => StagedFiles.Count > 0;
+
+    public string StagedFilesSummary
+    {
+        get;
+        private set => this.RaiseAndSetIfChanged(ref field, value);
+    } = string.Empty;
+
     public string Draft
     {
         get;
@@ -51,7 +62,10 @@ public sealed class MessageComposerViewModel : ViewModelBase
 
         Autocomplete = new AutocompleteController([mentionProvider, channelProvider]);
 
-        IObservable<bool> canSend = this.WhenAnyValue(x => x.Draft, draft => !string.IsNullOrWhiteSpace(draft));
+        IObservable<bool> canSend = this.WhenAnyValue(
+            x => x.Draft,
+            x => x.HasStagedFiles,
+            (draft, hasFiles) => !string.IsNullOrWhiteSpace(draft) || hasFiles);
         SendCommand = ReactiveCommand.Create(Send, canSend);
 
         _ = this.WhenAnyValue(x => x.Draft).Subscribe(OnDraftChanged);
@@ -75,12 +89,38 @@ public sealed class MessageComposerViewModel : ViewModelBase
         }
     }
 
-    public void RequestFileUpload(string filePath)
+    public void StageFiles(IEnumerable<string> filePaths)
     {
-        if (!string.IsNullOrEmpty(ServerUrl))
+        int remaining = HubConstants.MaxAttachmentsPerMessage - StagedFiles.Count;
+        foreach (string path in filePaths)
         {
-            FileUploadRequested?.Invoke(ServerUrl, filePath);
+            if (remaining <= 0)
+            {
+                break;
             }
+
+            if (StagedFiles.Any(f => f.FilePath == path))
+            {
+                continue;
+            }
+
+            StagedFiles.Add(new StagedFile(path, Path.GetFileName(path)));
+            remaining--;
+        }
+
+        UpdateStagedSummary();
+    }
+
+    public void RemoveStagedFile(StagedFile file)
+    {
+        _ = StagedFiles.Remove(file);
+        UpdateStagedSummary();
+    }
+
+    public void ClearStagedFiles()
+    {
+        StagedFiles.Clear();
+        UpdateStagedSummary();
     }
 
     public void SetServer(string serverUrl, bool isConnected = true)
@@ -113,6 +153,14 @@ public sealed class MessageComposerViewModel : ViewModelBase
         Autocomplete.Reset();
     }
 
+    private void UpdateStagedSummary()
+    {
+        this.RaisePropertyChanged(nameof(HasStagedFiles));
+        StagedFilesSummary = StagedFiles.Count > 0
+            ? $"{StagedFiles.Count} file(s) staged"
+            : string.Empty;
+    }
+
     private void OnDraftChanged(string? draft)
     {
         Autocomplete.Update(draft ?? string.Empty);
@@ -121,20 +169,18 @@ public sealed class MessageComposerViewModel : ViewModelBase
     private void Send()
     {
         string text = Draft.Trim();
-        if (string.IsNullOrWhiteSpace(text))
-        {
-            return;
-        }
-
         Draft = string.Empty;
 
         if (_commandHandler is not null && _commandHandler.IsCommand(text))
         {
             _ = (CommandRequested?.Invoke(text));
+            return;
         }
-        else
+
-        {
+        List<string> filePaths = StagedFiles.Select(f => f.FilePath).ToList();
-            SendRequested?.Invoke(ServerUrl, text);
+        StagedFiles.Clear();
-        }
+        UpdateStagedSummary();
+
+        SendRequested?.Invoke(ServerUrl, text, filePaths);
     }
 }

src/Decho/Views/MessageComposerView.axaml

@@ -1,10 +1,54 @@
 <UserControl xmlns="https://github.com/avaloniaui"
              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
              xmlns:vm="using:Decho.ViewModels"
+             xmlns:models="using:Decho.Models"
              xmlns:i="https://github.com/projektanker/icons.avalonia"
              x:Class="Decho.Views.MessageComposerView"
              x:DataType="vm:MessageComposerViewModel">
-    <Grid>
+    <Grid RowDefinitions="Auto,*">
+        <Border IsVisible="{Binding HasStagedFiles}"
+                Background="{DynamicResource UiTheme02}"
+                CornerRadius="4"
+                Padding="6"
+                Margin="0 0 0 4">
+            <DockPanel>
+                <Button DockPanel.Dock="Right"
+                        Content="Clear"
+                        FontSize="11"
+                        Padding="4 0"
+                        HorizontalAlignment="Right"
+                        Click="OnClearStagedClick" />
+                <ItemsControl ItemsSource="{Binding StagedFiles}"
+                              VerticalAlignment="Center">
+                    <ItemsControl.ItemsPanel>
+                        <ItemsPanelTemplate>
+                            <WrapPanel />
+                        </ItemsPanelTemplate>
+                    </ItemsControl.ItemsPanel>
+                    <ItemsControl.ItemTemplate>
+                        <DataTemplate x:DataType="models:StagedFile">
+                            <Border Background="{DynamicResource UiTheme03}"
+                                    CornerRadius="3"
+                                    Padding="4 2"
+                                    Margin="0 0 4 2">
+                                <DockPanel>
+                                    <TextBlock Text="{Binding FileName}"
+                                               FontSize="11"
+                                               VerticalAlignment="Center" />
+                                    <Button Content="x"
+                                            FontSize="10"
+                                            Padding="2 0"
+                                            Margin="4 0 0 0"
+                                            Cursor="Hand"
+                                            Click="OnRemoveStagedClick" />
+                                </DockPanel>
+                            </Border>
+                        </DataTemplate>
+                    </ItemsControl.ItemTemplate>
+                </ItemsControl>
+            </DockPanel>
+        </Border>
+        <Grid Grid.Row="1">
             <Grid.ColumnDefinitions>
                 <ColumnDefinition Width="*" />
                 <ColumnDefinition Width="Auto" />
@@ -65,4 +109,5 @@
                     i:Attached.Icon="fa-paperclip"
                     IsEnabled="{Binding IsConnected}" />
         </Grid>
+    </Grid>
 </UserControl>

src/Decho/Views/MessageComposerView.axaml.cs

@@ -4,6 +4,7 @@ using Avalonia.Interactivity;
 using Avalonia.Media;
 using Avalonia.Platform.Storage;
 
+using Decho.Models;
 using Decho.ViewModels;
 
 using System.Globalization;
@@ -134,17 +135,40 @@ public partial class MessageComposerView : UserControl
 
         IReadOnlyList<IStorageFile> files = await topLevel.StorageProvider.OpenFilePickerAsync(new FilePickerOpenOptions
         {
-            AllowMultiple = false,
+            AllowMultiple = true,
-            Title = "Select a file to upload",
+            Title = "Select files to attach",
         });
 
-        IStorageFile? file = files?.FirstOrDefault();
+        List<string> paths = [];
-        if (file?.TryGetLocalPath() is string path)
+        foreach (IStorageFile file in files)
         {
-            vm.RequestFileUpload(path);
+            if (file.TryGetLocalPath() is string path)
+            {
+                paths.Add(path);
             }
         }
 
+        if (paths.Count > 0)
+        {
+            vm.StageFiles(paths);
+        }
+    }
+
+    private void OnRemoveStagedClick(object? sender, RoutedEventArgs e)
+    {
+        if (sender is Button button && button.DataContext is StagedFile file)
+        {
+            MessageComposerViewModel? vm = this.GetDataContext<MessageComposerViewModel>();
+            vm?.RemoveStagedFile(file);
+        }
+    }
+
+    private void OnClearStagedClick(object? sender, RoutedEventArgs e)
+    {
+        MessageComposerViewModel? vm = this.GetDataContext<MessageComposerViewModel>();
+        vm?.ClearStagedFiles();
+    }
+
     private void OnDragOver(object? sender, DragEventArgs e)
     {
 #pragma warning disable CS0618
@@ -164,14 +188,16 @@ public partial class MessageComposerView : UserControl
         }
 
 #pragma warning disable CS0618
-        string? paths = e.Data.GetFiles()?
+        List<string> paths = e.Data.GetFiles()?
             .Select(f => f.TryGetLocalPath())
-            .FirstOrDefault(p => p is not null);
+            .Where(p => p is not null)
+            .Cast<string>()
+            .ToList() ?? [];
 #pragma warning restore CS0618
 
-        if (paths is string path)
+        if (paths.Count > 0)
         {
-            vm.RequestFileUpload(path);
+            vm.StageFiles(paths);
         }
     }
 }