Element preview

src/AppCommon/FileTime.App.Core.Abstraction/Models/FileExtension.cs

@@ -0,0 +1,3 @@
+namespace FileTime.App.Core.Models;
+
+public record FileExtension(long? Size);

src/AppCommon/FileTime.App.Core.Abstraction/Models/ItemPreviewMode.cs

@@ -0,0 +1,8 @@
+namespace FileTime.App.Core.Models;
+
+public enum ItemPreviewMode
+{
+    Unknown,
+    Text,
+    Empty
+}

src/AppCommon/FileTime.App.Core.Abstraction/Services/IItemPreviewService.cs

@@ -0,0 +1,8 @@
+using FileTime.App.Core.ViewModels.ItemPreview;
+
+namespace FileTime.App.Core.Services;
+
+public interface IItemPreviewService
+{
+    IObservable<IItemPreviewViewModel?> ItemPreview { get; }
+}

src/AppCommon/FileTime.App.Core.Abstraction/ViewModels/IFileViewModel.cs

@@ -1,9 +1,10 @@
+using FileTime.App.Core.Models;
 using FileTime.App.Core.Models.Enums;
 using FileTime.Core.Models;
 using InitableService;
 
 namespace FileTime.App.Core.ViewModels;
 
-public interface IFileViewModel : IElementViewModel, IInitable<IFileElement, ITabViewModel, ItemViewModelType>
+public interface IFileViewModel : IElementViewModel, IInitable<IElement, FileExtension, ITabViewModel, ItemViewModelType>
 {
 }

src/AppCommon/FileTime.App.Core.Abstraction/ViewModels/ItemPreview/IItemPreviewViewModel.cs

@@ -0,0 +1,8 @@
+using FileTime.App.Core.Models;
+
+namespace FileTime.App.Core.ViewModels.ItemPreview;
+
+public interface IItemPreviewViewModel
+{
+    ItemPreviewMode Mode { get; }
+}

src/AppCommon/FileTime.App.Core/Services/ItemPreviewService.cs

@@ -0,0 +1,40 @@
+using System.Reactive.Linq;
+using FileTime.App.Core.ViewModels;
+using FileTime.App.Core.ViewModels.ItemPreview;
+using FileTime.Core.Models;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace FileTime.App.Core.Services;
+
+public class ItemPreviewService : IItemPreviewService
+{
+    private readonly IServiceProvider _serviceProvider;
+    public IObservable<IItemPreviewViewModel?> ItemPreview { get; }
+
+    public ItemPreviewService(IAppState appState, IServiceProvider serviceProvider)
+    {
+        _serviceProvider = serviceProvider;
+        ItemPreview = appState
+            .SelectedTab
+            .Select(t => t?.CurrentSelectedItem.Throttle(TimeSpan.FromMilliseconds(250)) ?? Observable.Return<IItemViewModel?>(null))
+            .Switch()
+            .Select(item =>
+                item == null
+                    ? Observable.Return<IItemPreviewViewModel?>(null)
+                    : Observable.FromAsync(async () => await Map(item))
+            )
+            .Switch()
+            .Publish(null)
+            .RefCount();
+    }
+
+    private async Task<IItemPreviewViewModel?> Map(IItemViewModel itemViewModel)
+    {
+        return itemViewModel.BaseItem switch
+        {
+            IElement element => await _serviceProvider.GetAsyncInitableResolver(element)
+                .GetRequiredServiceAsync<ElementPreviewViewModel>(),
+            _ => null
+        };
+    }
+}

src/AppCommon/FileTime.App.Core/Startup.cs

@@ -2,6 +2,7 @@ using FileTime.App.Core.Services;
 using FileTime.App.Core.Services.UserCommandHandler;
 using FileTime.App.Core.StartupServices;
 using FileTime.App.Core.ViewModels;
+using FileTime.App.Core.ViewModels.ItemPreview;
 using Microsoft.Extensions.DependencyInjection;
 
 namespace FileTime.App.Core;
@@ -17,10 +18,12 @@ public static class Startup
             .AddTransient<IFileViewModel, FileViewModel>()
             .AddTransient<IContainerSizeContainerViewModel, ContainerSizeContainerViewModel>()
             .AddTransient<IItemNameConverterService, ItemNameConverterService>()
+            .AddTransient<ElementPreviewViewModel>()
             .AddSingleton<IUserCommandHandlerService, UserCommandHandlerService>()
             .AddSingleton<IClipboardService, ClipboardService>()
             .AddSingleton<IIdentifiableUserCommandService, IdentifiableUserCommandService>()
             .AddSingleton<IStartupHandler, DefaultIdentifiableCommandHandlerRegister>()
+            .AddSingleton<IItemPreviewService, ItemPreviewService>()
             .AddCommandHandlers();
     }
 

src/AppCommon/FileTime.App.Core/ViewModels/FileViewModel.cs

@@ -1,3 +1,4 @@
+using FileTime.App.Core.Models;
 using FileTime.App.Core.Models.Enums;
 using FileTime.App.Core.Services;
 using FileTime.Core.Models;
@@ -12,8 +13,9 @@ public partial class FileViewModel : ElementViewModel, IFileViewModel
     {
     }
 
-    public void Init(IFileElement item, ITabViewModel parentTab, ItemViewModelType itemViewModelType)
+    public void Init(IElement item, FileExtension fileExtension, ITabViewModel parentTab, ItemViewModelType itemViewModelType)
     {
         Init((IElement)item, parentTab, itemViewModelType);
+        Size = fileExtension.Size;
     }
 }

src/AppCommon/FileTime.App.Core/ViewModels/ItemPreview/ElementPreviewViewModel.cs

@@ -0,0 +1,39 @@
+using System.Text;
+using FileTime.App.Core.Models;
+using FileTime.Core.Models;
+using InitableService;
+using MvvmGen;
+
+namespace FileTime.App.Core.ViewModels.ItemPreview;
+
+[ViewModel]
+public partial class ElementPreviewViewModel : IItemPreviewViewModel, IAsyncInitable<IElement>
+{
+    private const int MaxTextPreviewSize = 1024 * 1024;
+    
+    public ItemPreviewMode Mode { get; private set; }
+
+    [Property] private string? _textContent;
+    
+    public async Task InitAsync(IElement element)
+    {
+        try
+        {
+            var content = await element.Provider.GetContentAsync(element, MaxTextPreviewSize);
+
+            TextContent = content is null
+                ? "Could not read any data from file " + element.Name
+                : Encoding.UTF8.GetString(content);
+        }
+        catch(Exception ex)
+        {
+            TextContent = $"Error while getting content of {element.FullName}. " + ex.ToString();
+        }
+
+        Mode = (TextContent?.Length ?? 0) switch
+        {
+            0 => ItemPreviewMode.Empty,
+            _ => ItemPreviewMode.Text
+        };
+    }
+}

src/AppCommon/FileTime.App.Core/ViewModels/TabViewModel.cs

@@ -4,6 +4,7 @@ using FileTime.App.Core.Extensions;
 using FileTime.App.Core.Models;
 using FileTime.App.Core.Models.Enums;
 using FileTime.App.Core.Services;
+using FileTime.App.Core.ViewModels.ItemPreview;
 using FileTime.Core.Models;
 using FileTime.Core.Services;
 using Microsoft.Extensions.DependencyInjection;
@@ -34,9 +35,14 @@ public partial class TabViewModel : ITabViewModel, IDisposable
     public IObservable<IObservable<IChangeSet<IItemViewModel>>?> SelectedsChildren { get; private set; } = null!;
     public IObservable<IObservable<IChangeSet<IItemViewModel>>?> ParentsChildren { get; private set; } = null!;
 
-    public IObservable<IReadOnlyCollection<IItemViewModel>?> CurrentItemsCollectionObservable { get; private set; } = null!;
+    public IObservable<IReadOnlyCollection<IItemViewModel>?> CurrentItemsCollectionObservable { get; private set; } =
-    public IObservable<IReadOnlyCollection<IItemViewModel>?> ParentsChildrenCollectionObservable { get; private set; } = null!;
+        null!;
-    public IObservable<IReadOnlyCollection<IItemViewModel>?> SelectedsChildrenCollectionObservable { get; private set; } = null!;
+
+    public IObservable<IReadOnlyCollection<IItemViewModel>?> ParentsChildrenCollectionObservable { get; private set; } =
+        null!;
+
+    public IObservable<IReadOnlyCollection<IItemViewModel>?>
+        SelectedsChildrenCollectionObservable { get; private set; } = null!;
 
     [Property] private BindedCollection<IItemViewModel>? _currentItemsCollection;
 
@@ -78,7 +84,7 @@ public partial class TabViewModel : ITabViewModel, IDisposable
                     tab.CurrentSelectedItem,
                     (currentItems, currentSelectedItemPath) =>
                         currentItems == null
-                            ? Observable.Return((IItemViewModel?) null)
+                            ? Observable.Return((IItemViewModel?)null)
                             : currentItems
                                 .ToCollection()
                                 .Select(items =>
@@ -117,7 +123,7 @@ public partial class TabViewModel : ITabViewModel, IDisposable
                                 .Transform(i => MapItemToViewModel(i, ItemViewModelType.SelectedChild))),
                     currentSelectedItemThrottled
                         .Where(c => c is null or not IContainerViewModel)
-                        .Select(_ => (IObservable<IChangeSet<IItemViewModel>>?) null)
+                        .Select(_ => (IObservable<IChangeSet<IItemViewModel>>?)null)
                 )
                 /*.ObserveOn(_rxSchedulerService.GetWorkerScheduler())
                 .SubscribeOn(_rxSchedulerService.GetUIScheduler())*/
@@ -136,7 +142,7 @@ public partial class TabViewModel : ITabViewModel, IDisposable
             return Observable.Merge(
                     parentThrottled
                         .Where(p => p is not null)
-                        .Select(p => Observable.FromAsync(async () => (IContainer) await p!.ResolveAsync()))
+                        .Select(p => Observable.FromAsync(async () => (IContainer)await p!.ResolveAsync()))
                         .Switch()
                         .Select(p => p.Items)
                         .Switch()
@@ -145,7 +151,7 @@ public partial class TabViewModel : ITabViewModel, IDisposable
                                 .Transform(i => MapItemToViewModel(i, ItemViewModelType.Parent))),
                     parentThrottled
                         .Where(p => p is null)
-                        .Select(_ => (IObservable<IChangeSet<IItemViewModel>>?) null)
+                        .Select(_ => (IObservable<IChangeSet<IItemViewModel>>?)null)
                 )
                 /*.ObserveOn(_rxSchedulerService.GetWorkerScheduler())
                 .SubscribeOn(_rxSchedulerService.GetUIScheduler())*/
@@ -158,7 +164,7 @@ public partial class TabViewModel : ITabViewModel, IDisposable
         {
             return source
                 .Select(c =>
-                    c != null ? c.ToCollection() : Observable.Return((IReadOnlyCollection<IItemViewModel>?) null))
+                    c != null ? c.ToCollection() : Observable.Return((IReadOnlyCollection<IItemViewModel>?)null))
                 .Switch()
                 .Publish(null)
                 .RefCount();
@@ -179,16 +185,20 @@ public partial class TabViewModel : ITabViewModel, IDisposable
 
             return containerViewModel;
         }
-        else if (item is IFileElement fileElement)
+        else if (item is IElement element)
+        {
+            var fileExtension = element.GetExtension<FileExtension>();
+
+            if (fileExtension is not null)
             {
                 var fileViewModel = _serviceProvider
-                .GetInitableResolver<IFileElement, ITabViewModel, ItemViewModelType>(fileElement, this, type)
+                    .GetInitableResolver<IElement, FileExtension, ITabViewModel, ItemViewModelType>(
+                        element, fileExtension, this, type)
                     .GetRequiredService<IFileViewModel>();
-            fileViewModel.Size = fileElement.Size;
 
                 return fileViewModel;
             }
-        else if (item is IElement element)
+            else
             {
                 var elementViewModel = _serviceProvider
                     .GetInitableResolver<IElement, ITabViewModel, ItemViewModelType>(element, this, type)
@@ -196,6 +206,7 @@ public partial class TabViewModel : ITabViewModel, IDisposable
 
                 return elementViewModel;
             }
+        }
 
         throw new ArgumentException($"{nameof(item)} is not {nameof(IContainer)} neither {nameof(IElement)}");
     }

src/Core/FileTime.Core.Abstraction/Models/ExtensionCollection.cs

@@ -0,0 +1,47 @@
+using System.Collections;
+using System.Diagnostics.CodeAnalysis;
+using System.Runtime.CompilerServices;
+
+namespace FileTime.Core.Models;
+
+public class ExtensionCollection : IEnumerable<object>
+{
+    private readonly List<object> _extensions = new();
+
+    public ExtensionCollection()
+    {
+    }
+
+    public ExtensionCollection(IEnumerable<object> objects)
+    {
+        foreach (var obj in objects)
+        {
+            AddSafe(obj);
+        }
+    }
+
+    private void AddSafe(object obj)
+    {
+        var objType = obj.GetType();
+        if (_extensions.Any(i => i.GetType() == objType))
+            throw new ArgumentException($"Collection already contains an item with type {objType.FullName}");
+
+        _extensions.Add(obj);
+    }
+
+    public void Add<T>([DisallowNull] T obj, [CallerArgumentExpression("obj")] string? paramName = null)
+    {
+        ArgumentNullException.ThrowIfNull(obj, paramName);
+        AddSafe(obj);
+    }
+
+    public void Remove<T>()
+    {
+        _extensions.RemoveAll(i => i is T);
+    }
+
+    public ReadOnlyExtensionCollection AsReadOnly() => new ReadOnlyExtensionCollection(this);
+
+    public IEnumerator<object> GetEnumerator() => _extensions.GetEnumerator();
+    IEnumerator IEnumerable.GetEnumerator() => _extensions.GetEnumerator();
+}

src/Core/FileTime.Core.Abstraction/Models/IFileElement.cs

@@ -1,6 +0,0 @@
-namespace FileTime.Core.Models;
-
-public interface IFileElement : IElement
-{
-    long Size { get; }
-}

src/Core/FileTime.Core.Abstraction/Models/IItem.cs

@@ -1,3 +1,4 @@
+using System.Reactive.Linq;
 using FileTime.Core.Enums;
 using FileTime.Core.Services;
 
@@ -19,4 +20,7 @@ public interface IItem
     string? Attributes { get; }
     AbsolutePathType Type { get; }
     IObservable<IEnumerable<Exception>> Exceptions { get; }
+    ReadOnlyExtensionCollection Extensions { get; }
+
+    T? GetExtension<T>() => (T?)Extensions.FirstOrDefault(i => i is T);
 }

src/Core/FileTime.Core.Abstraction/Models/ReadOnlyExtensionCollection.cs

@@ -0,0 +1,17 @@
+using System.Collections;
+
+namespace FileTime.Core.Models;
+
+public class ReadOnlyExtensionCollection : IEnumerable<object>
+{
+    private readonly ExtensionCollection _collection;
+
+    public ReadOnlyExtensionCollection(ExtensionCollection collection)
+    {
+        _collection = collection;
+    }
+
+    public IEnumerator<object> GetEnumerator() => _collection.GetEnumerator();
+
+    IEnumerator IEnumerable.GetEnumerator() => _collection.GetEnumerator();
+}

src/Core/FileTime.Core.Abstraction/Services/IContentProvider.cs

@@ -20,4 +20,6 @@ public interface IContentProvider : IContainer, IOnContainerEnter
 
     Task<List<IAbsolutePath>> GetItemsByContainerAsync(FullName fullName);
     NativePath GetNativePath(FullName fullName);
+
+    Task<byte[]?> GetContentAsync(IElement element, int? maxLength = null, CancellationToken cancellationToken = default);
 }

src/Core/FileTime.Core.Models/Container.cs

@@ -1,3 +1,4 @@
+using System.Collections.ObjectModel;
 using System.Reactive.Linq;
 using System.Reactive.Subjects;
 using DynamicData;
@@ -20,6 +21,7 @@ public record Container(
     string? Attributes,
     IContentProvider Provider,
     IObservable<IEnumerable<Exception>> Exceptions,
+    ReadOnlyExtensionCollection Extensions,
     IObservable<IObservable<IChangeSet<IAbsolutePath>>?> Items) : IContainer
 {
     BehaviorSubject<bool> IsLoading { get; } = new BehaviorSubject<bool>(false);

src/Core/FileTime.Core.Models/Element.cs

@@ -1,3 +1,4 @@
+using System.Collections.ObjectModel;
 using FileTime.Core.Enums;
 using FileTime.Core.Services;
 
@@ -16,7 +17,8 @@ public record Element(
     bool CanRename,
     string? Attributes,
     IContentProvider Provider,
-    IObservable<IEnumerable<Exception>> Exceptions) : IElement
+    IObservable<IEnumerable<Exception>> Exceptions,
+    ReadOnlyExtensionCollection Extensions) : IElement
 {
     public AbsolutePathType Type => AbsolutePathType.Element;
 }

src/Core/FileTime.Core.Models/FileElement.cs

@@ -1,35 +0,0 @@
-using FileTime.Core.Enums;
-using FileTime.Core.Services;
-
-namespace FileTime.Core.Models;
-
-public record FileElement(
-        string Name,
-        string DisplayName,
-        FullName FullName,
-        NativePath NativePath,
-        IAbsolutePath? Parent,
-        bool IsHidden,
-        bool IsExists,
-        DateTime? CreatedAt,
-        SupportsDelete CanDelete,
-        bool CanRename,
-        string? Attributes,
-        IContentProvider Provider,
-        IObservable<IEnumerable<Exception>> Exceptions,
-        long Size)
-    : Element(
-        Name,
-        DisplayName,
-        FullName,
-        NativePath,
-        Parent,
-        IsHidden,
-        IsExists,
-        CreatedAt,
-        CanDelete,
-        CanRename,
-        Attributes,
-        Provider,
-        Exceptions
-    ), IFileElement;

src/Core/FileTime.Core.Services/ContentProviderBase.cs

@@ -1,3 +1,4 @@
+using System.Collections.ObjectModel;
 using System.Reactive.Linq;
 using System.Reactive.Subjects;
 using DynamicData;
@@ -8,7 +9,10 @@ namespace FileTime.Core.Services;
 
 public abstract class ContentProviderBase : IContentProvider
 {
+    private readonly ReadOnlyExtensionCollection _extensions;
+
     protected BehaviorSubject<IObservable<IChangeSet<IAbsolutePath>>?> Items { get; } = new(null);
+    protected ExtensionCollection Extensions { get; }
 
     IObservable<IObservable<IChangeSet<IAbsolutePath>>?> IContainer.Items => Items;
 
@@ -44,10 +48,14 @@ public abstract class ContentProviderBase : IContentProvider
 
     public IObservable<IEnumerable<Exception>> Exceptions => Observable.Return(Enumerable.Empty<Exception>());
 
+    ReadOnlyExtensionCollection IItem.Extensions => _extensions;
+
     protected ContentProviderBase(string name)
     {
         DisplayName = Name = name;
         FullName = new FullName(name);
+        Extensions = new ExtensionCollection();
+        _extensions = Extensions.AsReadOnly();
     }
 
     public virtual Task OnEnter() => Task.CompletedTask;
@@ -57,7 +65,8 @@ public abstract class ContentProviderBase : IContentProvider
         bool forceResolve = false,
         AbsolutePathType forceResolvePathType = AbsolutePathType.Unknown,
         ItemInitializationSettings itemInitializationSettings = default)
-        => await GetItemByNativePathAsync(GetNativePath(fullName), forceResolve, forceResolvePathType, itemInitializationSettings);
+        => await GetItemByNativePathAsync(GetNativePath(fullName), forceResolve, forceResolvePathType,
+            itemInitializationSettings);
 
     public abstract Task<IItem> GetItemByNativePathAsync(
         NativePath nativePath,
@@ -67,4 +76,8 @@ public abstract class ContentProviderBase : IContentProvider
 
     public abstract Task<List<IAbsolutePath>> GetItemsByContainerAsync(FullName fullName);
     public abstract NativePath GetNativePath(FullName fullName);
+
+    public abstract Task<byte[]?> GetContentAsync(IElement element,
+        int? maxLength = null,
+        CancellationToken cancellationToken = default);
 }

src/GuiApp/Avalonia/FileTime.GuiApp/ViewModels/MainWindowViewModel.cs

@@ -20,6 +20,7 @@ namespace FileTime.GuiApp.ViewModels;
 [Inject(typeof(IKeyInputHandlerService), PropertyName = "_keyInputHandlerService")]
 [Inject(typeof(IUserCommandHandlerService), PropertyAccessModifier = AccessModifier.Public)]
 [Inject(typeof(LifecycleService), PropertyName = "_lifecycleService")]
+[Inject(typeof(IItemPreviewService), PropertyAccessModifier = AccessModifier.Public)]
 public partial class MainWindowViewModel : IMainWindowViewModelBase
 {
     public bool Loading => false;

src/GuiApp/Avalonia/FileTime.GuiApp/Views/MainWindow.axaml

@@ -8,6 +8,7 @@
     xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
     xmlns:vm="using:FileTime.GuiApp.ViewModels"
     xmlns:config="using:FileTime.GuiApp.Configuration"
+    xmlns:appCoreModels="using:FileTime.App.Core.Models"
     Title="FileTime"
     d:DesignHeight="450"
     d:DesignWidth="800"
@@ -44,7 +45,8 @@
                     <StackPanel
                         Margin="20,10"
                         Orientation="Horizontal">
-                        <local:PathPresenter DataContext="{Binding AppState.SelectedTab^.CurrentLocation^.FullName.Path,Converter={StaticResource PathPreformatter}}"/>
+                        <local:PathPresenter
+                            DataContext="{Binding AppState.SelectedTab^.CurrentLocation^.FullName.Path,Converter={StaticResource PathPreformatter}}" />
                         <TextBlock
                             Foreground="{StaticResource AccentBrush}"
                             Text="{Binding AppState.SelectedTab^.CurrentSelectedItem^.DisplayNameText}" />
@@ -53,7 +55,8 @@
 
                 <Grid Grid.Row="1" RowDefinitions="Auto,Auto,Auto,Auto">
 
-					<Border CornerRadius="10" Background="{DynamicResource ContainerBackgroundBrush}" Padding="10" Margin="10">
+                    <Border CornerRadius="10" Background="{DynamicResource ContainerBackgroundBrush}" Padding="10"
+                            Margin="10">
                         <Grid RowDefinitions="Auto,Auto">
 
                             <TextBlock
@@ -65,8 +68,10 @@
                                 Items="{Binding AppState.RootDriveInfos.Collection}">
                                 <ItemsRepeater.ItemTemplate>
                                     <DataTemplate x:DataType="vm:RootDriveInfo">
-										<Grid Classes="SidebarContainerPresenter" PointerPressed="OnHasContainerPointerPressed" Cursor="Hand">
+                                        <Grid Classes="SidebarContainerPresenter"
-											<Grid Margin="0,5" ColumnDefinitions="Auto,*,Auto" RowDefinitions="Auto,Auto">
+                                              PointerPressed="OnHasContainerPointerPressed" Cursor="Hand">
+                                            <Grid Margin="0,5" ColumnDefinitions="Auto,*,Auto"
+                                                  RowDefinitions="Auto,Auto">
                                                 <Image
                                                     Grid.RowSpan="2"
                                                     Width="20"
@@ -90,7 +95,8 @@
                                                         Margin="5,0,0,0"
                                                         VerticalAlignment="Center"
                                                         Classes="ExtraSmallText"
-														Text="{Binding Label}" IsVisible="{Binding Label,Converter={x:Static StringConverters.IsNotNullOrEmpty}}" />
+                                                        Text="{Binding Label}"
+                                                        IsVisible="{Binding Label,Converter={x:Static StringConverters.IsNotNullOrEmpty}}" />
                                                 </StackPanel>
 
                                                 <StackPanel
@@ -99,13 +105,16 @@
                                                     Orientation="Horizontal"
                                                     VerticalAlignment="Center">
 
-													<TextBlock Classes="SmallText" VerticalAlignment="Center" Text="{Binding Free, Converter={StaticResource FormatSizeConverter}, ConverterParameter=0}">
+                                                    <TextBlock Classes="SmallText" VerticalAlignment="Center"
+                                                               Text="{Binding Free, Converter={StaticResource FormatSizeConverter}, ConverterParameter=0}">
                                                     </TextBlock>
 
-													<TextBlock Classes="SmallText" VerticalAlignment="Center" Text=" / ">
+                                                    <TextBlock Classes="SmallText" VerticalAlignment="Center"
+                                                               Text=" / ">
                                                     </TextBlock>
 
-													<TextBlock Classes="SmallText" VerticalAlignment="Center" Text="{Binding Size, Converter={StaticResource FormatSizeConverter}, ConverterParameter=0}">
+                                                    <TextBlock Classes="SmallText" VerticalAlignment="Center"
+                                                               Text="{Binding Size, Converter={StaticResource FormatSizeConverter}, ConverterParameter=0}">
                                                     </TextBlock>
                                                 </StackPanel>
 
@@ -352,6 +361,8 @@
                                 Fill="{DynamicResource ContentSeparatorBrush}" />
 
                             <Grid Grid.Column="4">
+                                <Grid
+                                    IsVisible="{Binding ItemPreviewService.ItemPreview^,Converter={x:Static ObjectConverters.IsNull}}">
                                     <Grid
                                         IsVisible="{Binding AppState.SelectedTab^.SelectedsChildrenCollection.Collection, Converter={x:Static ObjectConverters.IsNotNull}, FallbackValue=False}">
                                         <ListBox
@@ -403,6 +414,18 @@
                                         </ItemsRepeater>
                                     </Grid>
                                 </Grid>
+                                <Grid
+                                    IsVisible="{Binding ItemPreviewService.ItemPreview^,Converter={x:Static ObjectConverters.IsNotNull}}">
+                                    <TextBlock HorizontalAlignment="Center" Text="Don't know how to preview this item." IsVisible="{Binding ItemPreviewService.ItemPreview^.Mode, Converter={StaticResource EqualityConverter}, ConverterParameter={x:Static appCoreModels:ItemPreviewMode.Unknown}}"/>
+                                    <TextBlock HorizontalAlignment="Center" Text="Empty" IsVisible="{Binding ItemPreviewService.ItemPreview^.Mode, Converter={StaticResource EqualityConverter}, ConverterParameter={x:Static appCoreModels:ItemPreviewMode.Empty}}"/>
+                                    <ScrollViewer IsVisible="{Binding ItemPreviewService.ItemPreview^.Mode, Converter={StaticResource EqualityConverter}, ConverterParameter={x:Static appCoreModels:ItemPreviewMode.Text}}">
+                                        <TextBox
+                                            IsReadOnly="True"
+                                            x:CompileBindings="False"
+                                            Text="{Binding ItemPreviewService.ItemPreview^.TextContent}" />
+                                    </ScrollViewer>
+                                </Grid>
+                            </Grid>
                         </Grid>
                     </Grid>
 

src/Providers/FileTime.Providers.Local/LocalContentProvider.cs

@@ -2,6 +2,7 @@ using System.Reactive.Linq;
 using System.Reactive.Subjects;
 using System.Runtime.InteropServices;
 using DynamicData;
+using FileTime.App.Core.Models;
 using FileTime.Core.Enums;
 using FileTime.Core.Models;
 using FileTime.Core.Services;
@@ -133,6 +134,7 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
             "???",
             this,
             nonNullExceptions,
+            new ExtensionCollection().AsReadOnly(),
             Observable.Return<IObservable<IChangeSet<IAbsolutePath>>?>(null)
         );
     }
@@ -195,6 +197,7 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
             GetDirectoryAttributes(directoryInfo),
             this,
             exceptions,
+            new ExtensionCollection().AsReadOnly(),
             Observable.FromAsync(async () => await Task.Run(InitChildren))
         );
 
@@ -226,7 +229,12 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
                              throw new Exception($"Path does not have parent: '{fileInfo.FullName}'");
         var parent = new AbsolutePath(this, parentFullName, AbsolutePathType.Container);
 
-        return new FileElement(
+        var extensions = new ExtensionCollection()
+        {
+            new FileExtension(fileInfo.Length)
+        };
+
+        return new Element(
             fileInfo.Name,
             fileInfo.Name,
             fullName,
@@ -240,7 +248,7 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
             GetFileAttributes(fileInfo),
             this,
             Observable.Return(Enumerable.Empty<Exception>()),
-            fileInfo.Length
+            extensions.AsReadOnly()
         );
     }
 
@@ -261,4 +269,28 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
         if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux) && !path.StartsWith("/")) path = "/" + path;
         return new NativePath(path);
     }
+
+    public override async Task<byte[]?> GetContentAsync(IElement element, int? maxLength = null,
+        CancellationToken cancellationToken = default)
+    {
+        if (cancellationToken.IsCancellationRequested) return null;
+        if (!File.Exists(element.NativePath!.Path))
+            throw new FileNotFoundException("File does not exist", element.NativePath.Path);
+        
+        await using var reader = new FileStream(element.NativePath!.Path, FileMode.Open, FileAccess.Read, FileShare.Read,
+            bufferSize: 1, // bufferSize == 1 used to avoid unnecessary buffer in FileStream
+            FileOptions.Asynchronous | FileOptions.SequentialScan);
+
+        var realFileSize = new FileInfo(element.NativePath!.Path).Length;
+        
+        var size = maxLength ?? realFileSize switch
+        {
+            > int.MaxValue => int.MaxValue,
+            _ => (int)realFileSize
+        };
+        var buffer = new byte[size];
+        await reader.ReadAsync(buffer, 0, size);
+
+        return buffer;
+    }
 }