Frequency navigation WIP

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

@@ -9,4 +9,5 @@ public interface IModalService
 
     void OpenModal(IModalViewModel modalToOpen);
     void CloseModal(IModalViewModel modalToClose);
+    T OpenModal<T>() where T : IModalViewModel;
 }

src/AppCommon/FileTime.App.Core.Abstraction/UserCommand/GoByFrequencyCommand.cs

@@ -0,0 +1,14 @@
+namespace FileTime.App.Core.UserCommand;
+
+public class GoByFrequencyCommand : IIdentifiableUserCommand
+{
+    public const string CommandName = "go_by_frequency";
+    
+    public static GoByFrequencyCommand Instance { get; } = new();
+    
+    private GoByFrequencyCommand()
+    {
+    }
+
+    public string UserCommandID => CommandName;
+}

src/AppCommon/FileTime.App.Core/FileTime.App.Core.csproj

@@ -25,6 +25,7 @@
     <ProjectReference Include="..\..\Tools\FileTime.Tools\FileTime.Tools.csproj" />
     <ProjectReference Include="..\FileTime.App.Core.Abstraction\FileTime.App.Core.Abstraction.csproj" />
     <ProjectReference Include="..\..\Core\FileTime.Core.Command\FileTime.Core.Command.csproj" />
+    <ProjectReference Include="..\FileTime.App.FrequencyNavigation.Abstractions\FileTime.App.FrequencyNavigation.Abstractions.csproj" />
   </ItemGroup>
 
 </Project>

src/AppCommon/FileTime.App.Core/Services/Persistence/TabPersistenceService.cs

@@ -63,7 +63,7 @@ public class TabPersistenceService : ITabPersistenceService
         _serviceProvider = serviceProvider;
         _localContentProvider = localContentProvider;
 
-        _jsonOptions = new JsonSerializerOptions()
+        _jsonOptions = new JsonSerializerOptions
         {
             PropertyNameCaseInsensitive = true,
             WriteIndented = true

src/AppCommon/FileTime.App.Core/Services/UserCommandHandler/NavigationUserCommandHandlerService.cs

@@ -2,6 +2,7 @@ using FileTime.App.Core.Extensions;
 using FileTime.App.Core.Models.Enums;
 using FileTime.App.Core.UserCommand;
 using FileTime.App.Core.ViewModels;
+using FileTime.App.FrequencyNavigation.Services;
 using FileTime.Core.Interactions;
 using FileTime.Core.Models;
 using FileTime.Core.Services;
@@ -20,6 +21,7 @@ public class NavigationUserCommandHandlerService : UserCommandHandlerServiceBase
     private readonly IUserCommandHandlerService _userCommandHandlerService;
     private readonly ITimelessContentProvider _timelessContentProvider;
     private readonly IUserCommunicationService _userCommunicationService;
+    private readonly IFrequencyNavigationService _frequencyNavigationService;
     private ITabViewModel? _selectedTab;
     private IContainer? _currentLocation;
     private IItemViewModel? _currentSelectedItem;
@@ -32,7 +34,8 @@ public class NavigationUserCommandHandlerService : UserCommandHandlerServiceBase
         ILocalContentProvider localContentProvider,
         IUserCommandHandlerService userCommandHandlerService,
         ITimelessContentProvider timelessContentProvider,
-        IUserCommunicationService userCommunicationService) : base(appState)
+        IUserCommunicationService userCommunicationService,
+        IFrequencyNavigationService frequencyNavigationService) : base(appState)
     {
         _appState = appState;
         _serviceProvider = serviceProvider;
@@ -40,6 +43,7 @@ public class NavigationUserCommandHandlerService : UserCommandHandlerServiceBase
         _userCommandHandlerService = userCommandHandlerService;
         _timelessContentProvider = timelessContentProvider;
         _userCommunicationService = userCommunicationService;
+        _frequencyNavigationService = frequencyNavigationService;
 
         SaveSelectedTab(t => _selectedTab = t);
         SaveCurrentSelectedItem(i => _currentSelectedItem = i);
@@ -53,6 +57,7 @@ public class NavigationUserCommandHandlerService : UserCommandHandlerServiceBase
             new TypeUserCommandHandler<CloseTabCommand>(CloseTab),
             new TypeUserCommandHandler<EnterRapidTravelCommand>(EnterRapidTravel),
             new TypeUserCommandHandler<ExitRapidTravelCommand>(ExitRapidTravel),
+            new TypeUserCommandHandler<GoByFrequencyCommand>(GoByFrequency),
             new TypeUserCommandHandler<GoToHomeCommand>(GoToHome),
             new TypeUserCommandHandler<GoToPathCommand>(GoToPath),
             new TypeUserCommandHandler<GoToProviderCommand>(GoToProvider),
@@ -71,6 +76,12 @@ public class NavigationUserCommandHandlerService : UserCommandHandlerServiceBase
         });
     }
 
+    private Task GoByFrequency()
+    {
+        _frequencyNavigationService.OpenNavigationWindow();
+        return Task.CompletedTask;
+    }
+
     private async Task GoToPath()
     {
         var pathInput = new TextInputElement("Path");

src/AppCommon/FileTime.App.Core/StartupServices/DefaultIdentifiableCommandHandlerRegister.cs

@@ -20,6 +20,7 @@ public class DefaultIdentifiableCommandHandlerRegister : IStartupHandler
         AddUserCommand(DeleteCommand.SoftDelete);
         AddUserCommand(EnterRapidTravelCommand.Instance);
         AddUserCommand(ExitRapidTravelCommand.Instance);
+        AddUserCommand(GoByFrequencyCommand.Instance);
         AddUserCommand(GoToHomeCommand.Instance);
         AddUserCommand(GoToPathCommand.Instance);
         AddUserCommand(GoToProviderCommand.Instance);

src/AppCommon/FileTime.App.DependencyInjection/DependencyInjection.cs

@@ -35,6 +35,7 @@ public static class DependencyInjection
         serviceCollection.TryAddSingleton<IApplicationSettings, ApplicationSettings>();
         serviceCollection.TryAddSingleton<ITabPersistenceService, TabPersistenceService>();
         serviceCollection.TryAddTransient<ITab, Tab>();
+        serviceCollection.TryAddSingleton<ITabEvents, TabEvents>();
         serviceCollection.AddSingleton<IExitHandler, ITabPersistenceService>(sp => sp.GetRequiredService<ITabPersistenceService>());
         serviceCollection.AddSingleton<IStartupHandler, ITabPersistenceService>(sp => sp.GetRequiredService<ITabPersistenceService>());
 

src/AppCommon/FileTime.App.FrequencyNavigation.Abstractions/FileTime.App.FrequencyNavigation.Abstractions.csproj

@@ -0,0 +1,14 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net7.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <RootNamespace>FileTime.App.FrequencyNavigation</RootNamespace>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\FileTime.App.Core.Abstraction\FileTime.App.Core.Abstraction.csproj" />
+  </ItemGroup>
+
+</Project>

src/AppCommon/FileTime.App.FrequencyNavigation.Abstractions/Services/IFrequencyNavigationService.cs

@@ -0,0 +1,12 @@
+using FileTime.App.FrequencyNavigation.ViewModels;
+
+namespace FileTime.App.FrequencyNavigation.Services;
+
+public interface IFrequencyNavigationService
+{
+    IObservable<bool> ShowWindow { get; }
+    IFrequencyNavigationViewModel? CurrentModal { get; }
+    void OpenNavigationWindow();
+    void CloseNavigationWindow();
+    IList<string> GetMatchingContainers(string searchText);
+}

src/AppCommon/FileTime.App.FrequencyNavigation.Abstractions/ViewModels/IFrequencyNavigationViewModel.cs

@@ -0,0 +1,12 @@
+using FileTime.App.Core.ViewModels;
+
+namespace FileTime.App.FrequencyNavigation.ViewModels;
+
+public interface IFrequencyNavigationViewModel : IModalViewModel
+{
+    IObservable<bool> ShowWindow { get; }
+    List<string> FilteredMatches { get; }
+    string SearchText { get; set; }
+    string SelectedItem { get; set; }
+    void Close();
+}

src/AppCommon/FileTime.App.FrequencyNavigation/FileTime.App.FrequencyNavigation.csproj

@@ -0,0 +1,25 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net7.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\Core\FileTime.Core.Abstraction\FileTime.Core.Abstraction.csproj" />
+    <ProjectReference Include="..\FileTime.App.Core.Abstraction\FileTime.App.Core.Abstraction.csproj" />
+    <ProjectReference Include="..\FileTime.App.FrequencyNavigation.Abstractions\FileTime.App.FrequencyNavigation.Abstractions.csproj" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="7.0.0" />
+    <PackageReference Include="MvvmGen" Version="1.1.5" />
+    <PackageReference Include="PropertyChanged.SourceGenerator" Version="1.0.8">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
+    <PackageReference Include="System.Reactive" Version="5.0.0" />
+  </ItemGroup>
+
+</Project>

src/AppCommon/FileTime.App.FrequencyNavigation/Models/ContainerFrequencyData.cs

@@ -0,0 +1,7 @@
+namespace FileTime.App.FrequencyNavigation.Models;
+
+public class ContainerFrequencyData
+{
+    public int Score { get; set; } = 1;
+    public DateTime LastAccessed { get; set; } = DateTime.Now;
+}

src/AppCommon/FileTime.App.FrequencyNavigation/Services/FrequencyNavigationService.cs

@@ -0,0 +1,194 @@
+using System.Reactive.Linq;
+using System.Reactive.Subjects;
+using System.Text.Json;
+using FileTime.App.Core.Models;
+using FileTime.App.Core.Services;
+using FileTime.App.FrequencyNavigation.Models;
+using FileTime.App.FrequencyNavigation.ViewModels;
+using FileTime.Core.Models;
+using FileTime.Core.Services;
+using Microsoft.Extensions.Logging;
+using PropertyChanged.SourceGenerator;
+
+namespace FileTime.App.FrequencyNavigation.Services;
+
+public partial class FrequencyNavigationService : IFrequencyNavigationService, IStartupHandler, IExitHandler
+{
+    private const int MaxAge = 10_000;
+
+    private DateTime _lastSave = DateTime.Now;
+    private readonly ILogger<FrequencyNavigationService> _logger;
+    private readonly IModalService _modalService;
+    private readonly SemaphoreSlim _saveLock = new(1);
+    private Dictionary<string, ContainerFrequencyData> _containerScores = new();
+    private readonly BehaviorSubject<bool> _showWindow = new(false);
+    private readonly string _dbPath;
+    [Notify] IFrequencyNavigationViewModel? _currentModal;
+    IObservable<bool> IFrequencyNavigationService.ShowWindow => _showWindow.AsObservable();
+
+    public FrequencyNavigationService(
+        ITabEvents tabEvents,
+        IApplicationSettings applicationSettings,
+        ILogger<FrequencyNavigationService> logger,
+        IModalService modalService)
+    {
+        _logger = logger;
+        _modalService = modalService;
+        _dbPath = Path.Combine(applicationSettings.AppDataRoot, "frequencyNavigationScores.json");
+        tabEvents.LocationChanged += OnTabLocationChanged;
+    }
+
+    void OnTabLocationChanged(object? sender, TabLocationChanged e)
+    {
+        IncreaseContainerScore(e.Location);
+    }
+
+    public void OpenNavigationWindow()
+    {
+        _showWindow.OnNext(true);
+        CurrentModal = _modalService.OpenModal<IFrequencyNavigationViewModel>();
+    }
+
+    public void CloseNavigationWindow()
+    {
+        _showWindow.OnNext(false);
+        if (_currentModal is not null)
+        {
+            _modalService.CloseModal(_currentModal);
+            CurrentModal = null;
+        }
+    }
+
+    private async void IncreaseContainerScore(FullName containerName)
+    {
+        await _saveLock.WaitAsync();
+        try
+        {
+            var containerNameString = containerName.Path;
+            if (_containerScores.ContainsKey(containerNameString))
+            {
+                _containerScores[containerNameString].Score++;
+                _containerScores[containerNameString].LastAccessed = DateTime.Now;
+            }
+            else
+            {
+                _containerScores.Add(containerNameString, new ContainerFrequencyData());
+            }
+        }
+        catch (Exception e)
+        {
+            _logger.LogError(e, "Error increasing container score");
+        }
+        finally
+        {
+            _saveLock.Release();
+        }
+
+        try
+        {
+            if (TryAgeContainerScores() || DateTime.Now - _lastSave > TimeSpan.FromMinutes(5))
+            {
+            }
+
+            await SaveStateAsync();
+        }
+        catch (Exception e)
+        {
+            _logger.LogError(e, "Error aging container scores");
+        }
+    }
+
+    private bool TryAgeContainerScores()
+    {
+        if (_containerScores.Select(c => c.Value.Score).Sum() < MaxAge)
+            return false;
+
+        AgeContainerScores();
+        return true;
+    }
+
+    private void AgeContainerScores()
+    {
+        var now = DateTime.Now;
+        var itemsToRemove = new List<string>();
+        foreach (var container in _containerScores)
+        {
+            var newScore = (int) Math.Floor(container.Value.Score * 0.9);
+            if (newScore > 0)
+            {
+                container.Value.Score = newScore;
+            }
+            else
+            {
+                itemsToRemove.Add(container.Key);
+            }
+        }
+
+        foreach (var itemToRemove in itemsToRemove)
+        {
+            _containerScores.Remove(itemToRemove);
+        }
+    }
+
+    public IList<string> GetMatchingContainers(string searchText)
+    {
+        if (string.IsNullOrWhiteSpace(searchText))
+            return new List<string>();
+
+        _saveLock.Wait();
+        var matchingContainers = _containerScores
+            .Where(c => c.Key.Contains(searchText, StringComparison.OrdinalIgnoreCase))
+            .OrderBy(c => GetWeightedScore(c.Value.Score, c.Value.LastAccessed))
+            .Select(c => c.Key)
+            .ToList();
+
+        _saveLock.Release();
+        return matchingContainers;
+    }
+
+    private int GetWeightedScore(int score, DateTime lastAccess)
+    {
+        var now = DateTime.Now;
+        var timeSinceLastAccess = now - lastAccess;
+        return timeSinceLastAccess.TotalHours switch
+        {
+            < 1 => score *= 4,
+            < 24 => score *= 2,
+            < 168 => score /= 2,
+            _ => score /= 4
+        };
+    }
+
+    public async Task InitAsync()
+    {
+        await LoadStateAsync();
+    }
+
+    private async Task LoadStateAsync()
+    {
+        if (!File.Exists(_dbPath))
+            return;
+
+        await _saveLock.WaitAsync();
+        await using var dbStream = File.OpenRead(_dbPath);
+        var containerScores = await JsonSerializer.DeserializeAsync<Dictionary<string, ContainerFrequencyData>>(dbStream);
+        if (containerScores is null) return;
+
+        _containerScores = containerScores;
+        _saveLock.Release();
+    }
+
+    public async Task ExitAsync()
+    {
+        await SaveStateAsync();
+    }
+
+    private async Task SaveStateAsync()
+    {
+        await _saveLock.WaitAsync();
+        _lastSave = DateTime.Now;
+        await using var dbStream = File.OpenWrite(_dbPath);
+        await JsonSerializer.SerializeAsync(dbStream, _containerScores);
+        _saveLock.Release();
+    }
+}

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

@@ -0,0 +1,20 @@
+using FileTime.App.Core.Services;
+using FileTime.App.FrequencyNavigation.Services;
+using FileTime.App.FrequencyNavigation.ViewModels;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.DependencyInjection.Extensions;
+
+namespace FileTime.App.FrequencyNavigation;
+
+public static class Startup
+{
+    public static IServiceCollection AddFrequencyNavigation(this IServiceCollection services)
+    {
+        services.TryAddTransient<IFrequencyNavigationViewModel, FrequencyNavigationViewModel>();
+        services.AddSingleton<FrequencyNavigationService>();
+        services.TryAddSingleton<IFrequencyNavigationService>(sp => sp.GetRequiredService<FrequencyNavigationService>());
+        services.AddSingleton<IStartupHandler>(sp => sp.GetRequiredService<FrequencyNavigationService>());
+        services.AddSingleton<IExitHandler>(sp => sp.GetRequiredService<FrequencyNavigationService>());
+        return services;
+    }
+}

src/AppCommon/FileTime.App.FrequencyNavigation/ViewModels/FrequencyNavigationViewModel.cs

@@ -0,0 +1,47 @@
+using FileTime.App.Core.ViewModels;
+using FileTime.App.FrequencyNavigation.Services;
+using MvvmGen;
+
+namespace FileTime.App.FrequencyNavigation.ViewModels;
+
+[ViewModel]
+[Inject(typeof(IFrequencyNavigationService), "_frequencyNavigationService")]
+public partial class FrequencyNavigationViewModel : IFrequencyNavigationViewModel
+{
+    private string _searchText;
+    
+    [Property] private IObservable<bool> _showWindow;
+    [Property] private List<string> _filteredMatches;
+    [Property] private string _selectedItem;
+
+    public string SearchText
+    {
+        get => _searchText;
+        set
+        {
+            if (_searchText == value) return;
+            
+            _searchText = value;
+            OnPropertyChanged();
+
+            UpdateFilteredMatches();
+        }
+    }
+
+    public void Close()
+    {
+        _frequencyNavigationService.CloseNavigationWindow();
+    }
+
+    partial void OnInitialize()
+    {
+        _showWindow = _frequencyNavigationService.ShowWindow;
+    }
+
+    private void UpdateFilteredMatches()
+    {
+        FilteredMatches = new List<string>(_frequencyNavigationService.GetMatchingContainers(_searchText));
+    }
+
+    string IModalViewModel.Name => "FrequencyNavigation";
+}

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

@@ -1,4 +1,5 @@
 using System.Reactive.Linq;
+using DynamicData;
 using FileTime.Core.ContentAccess;
 using FileTime.Core.Enums;
 using FileTime.Core.Timeline;
@@ -21,7 +22,7 @@ public interface IItem
     string? Attributes { get; }
     AbsolutePathType Type { get; }
     PointInTime PointInTime { get; }
-    IObservable<IEnumerable<Exception>> Exceptions { get; }
+    IObservable<IChangeSet<Exception>> Exceptions { get; }
     ReadOnlyExtensionCollection Extensions { get; }
 
     T? GetExtension<T>() => (T?)Extensions.FirstOrDefault(i => i is T);

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

@@ -0,0 +1,15 @@
+using FileTime.Core.Services;
+
+namespace FileTime.Core.Models;
+
+public class TabLocationChanged : EventArgs
+{
+    public FullName Location { get; }
+    public ITab Tab { get; }
+    
+    public TabLocationChanged(FullName location, ITab tab)
+    {
+        Location = location;
+        Tab = tab;
+    }
+}

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

@@ -0,0 +1,9 @@
+using FileTime.Core.Models;
+
+namespace FileTime.Core.Services;
+
+public interface ITabEvents
+{
+    event EventHandler<TabLocationChanged> LocationChanged;
+    void OnLocationChanged(ITab tab, FullName location);
+}

src/Core/FileTime.Core.ContentAccess/ContentProviderBase.cs

@@ -48,7 +48,8 @@ public abstract class ContentProviderBase : IContentProvider
     public AbsolutePathType Type => AbsolutePathType.Container;
     public PointInTime PointInTime { get; } = PointInTime.Eternal;
 
-    public IObservable<IEnumerable<Exception>> Exceptions => Observable.Return(Enumerable.Empty<Exception>());
+    protected SourceList<Exception> Exceptions { get; } = new();
+    IObservable<IChangeSet<Exception>> IItem.Exceptions => Exceptions.Connect();
 
     ReadOnlyExtensionCollection IItem.Extensions => _extensions;
 

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

@@ -22,7 +22,7 @@ public record Container(
     IContentProvider Provider,
     bool AllowRecursiveDeletion,
     PointInTime PointInTime,
-    IObservable<IEnumerable<Exception>> Exceptions,
+    IObservable<IChangeSet<Exception>> Exceptions,
     ReadOnlyExtensionCollection Extensions,
     IObservable<IObservable<IChangeSet<AbsolutePath, string>>?> Items) : IContainer
 {

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

@@ -1,3 +1,4 @@
+using DynamicData;
 using FileTime.Core.ContentAccess;
 using FileTime.Core.Enums;
 using FileTime.Core.Timeline;
@@ -18,7 +19,7 @@ public record Element(
     string? Attributes,
     IContentProvider Provider,
     PointInTime PointInTime,
-    IObservable<IEnumerable<Exception>> Exceptions,
+    IObservable<IChangeSet<Exception>> Exceptions,
     ReadOnlyExtensionCollection Extensions) : IElement
 {
     public AbsolutePathType Type => AbsolutePathType.Element;

src/Core/FileTime.Core.Services/Tab.cs

@@ -12,6 +12,7 @@ namespace FileTime.Core.Services;
 public class Tab : ITab
 {
     private readonly ITimelessContentProvider _timelessContentProvider;
+    private readonly ITabEvents _tabEvents;
     private readonly BehaviorSubject<IContainer?> _currentLocation = new(null);
     private readonly BehaviorSubject<IContainer?> _currentLocationForced = new(null);
     private readonly BehaviorSubject<AbsolutePath?> _currentSelectedItem = new(null);
@@ -24,9 +25,10 @@ public class Tab : ITab
     public IObservable<AbsolutePath?> CurrentSelectedItem { get; }
     public FullName? LastDeepestSelectedPath { get; private set; }
 
-    public Tab(ITimelessContentProvider timelessContentProvider)
+    public Tab(ITimelessContentProvider timelessContentProvider, ITabEvents tabEvents)
     {
         _timelessContentProvider = timelessContentProvider;
+        _tabEvents = tabEvents;
         _currentPointInTime = null!;
 
         _timelessContentProvider.CurrentPointInTime.Subscribe(p => _currentPointInTime = p);
@@ -60,7 +62,7 @@ public class Tab : ITab
                     ),
                     CurrentLocation
                         .Where(c => c is null)
-                        .Select(_ => (IObservable<IChangeSet<IItem, string>>?)null)
+                        .Select(_ => (IObservable<IChangeSet<IItem, string>>?) null)
                 )
                 .Publish(null)
                 .RefCount();
@@ -137,8 +139,25 @@ public class Tab : ITab
         return newSelectedItem;
     }
 
-    public void SetCurrentLocation(IContainer newLocation) => _currentLocation.OnNext(newLocation);
+    public void SetCurrentLocation(IContainer newLocation)
-    public void ForceSetCurrentLocation(IContainer newLocation) => _currentLocationForced.OnNext(newLocation);
+    {
+        _currentLocation.OnNext(newLocation);
+
+        if (newLocation.FullName != null)
+        {
+            _tabEvents.OnLocationChanged(this, newLocation.FullName);
+        }
+    }
+
+    public void ForceSetCurrentLocation(IContainer newLocation)
+    {
+        _currentLocationForced.OnNext(newLocation);
+
+        if (newLocation.FullName != null)
+        {
+            _tabEvents.OnLocationChanged(this, newLocation.FullName);
+        }
+    }
 
     public void SetSelectedItem(AbsolutePath newSelectedItem) => _currentSelectedItem.OnNext(newSelectedItem);
 

src/Core/FileTime.Core.Services/TabEvents.cs

@@ -0,0 +1,13 @@
+using FileTime.Core.Models;
+
+namespace FileTime.Core.Services;
+
+public class TabEvents : ITabEvents
+{
+    public event EventHandler<TabLocationChanged> LocationChanged;
+    
+    public void OnLocationChanged(ITab tab, FullName location)
+    {
+        LocationChanged?.Invoke(this, new TabLocationChanged(location, tab));
+    }
+}

src/FileTime.sln

@@ -63,6 +63,10 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "FileTime.GuiApp.Font", "Gui
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "FileTime.GuiApp.Font.Abstractions", "GuiApp\Avalonia\FileTime.GuiApp.Font.Abstractions\FileTime.GuiApp.Font.Abstractions.csproj", "{2D07F149-106B-4644-9586-D6218F78D868}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "FileTime.App.FrequencyNavigation", "AppCommon\FileTime.App.FrequencyNavigation\FileTime.App.FrequencyNavigation.csproj", "{253348AD-C9C0-4162-A2ED-C6FF8730B275}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "FileTime.App.FrequencyNavigation.Abstractions", "AppCommon\FileTime.App.FrequencyNavigation.Abstractions\FileTime.App.FrequencyNavigation.Abstractions.csproj", "{C1CA8B7E-F8E6-40AB-A45B-5EBEF6996290}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -157,6 +161,14 @@ Global
 		{2D07F149-106B-4644-9586-D6218F78D868}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{2D07F149-106B-4644-9586-D6218F78D868}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{2D07F149-106B-4644-9586-D6218F78D868}.Release|Any CPU.Build.0 = Release|Any CPU
+		{253348AD-C9C0-4162-A2ED-C6FF8730B275}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{253348AD-C9C0-4162-A2ED-C6FF8730B275}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{253348AD-C9C0-4162-A2ED-C6FF8730B275}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{253348AD-C9C0-4162-A2ED-C6FF8730B275}.Release|Any CPU.Build.0 = Release|Any CPU
+		{C1CA8B7E-F8E6-40AB-A45B-5EBEF6996290}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{C1CA8B7E-F8E6-40AB-A45B-5EBEF6996290}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{C1CA8B7E-F8E6-40AB-A45B-5EBEF6996290}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{C1CA8B7E-F8E6-40AB-A45B-5EBEF6996290}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -185,6 +197,8 @@ Global
 		{9B161766-A672-4D59-B591-C68907905158} = {3324D046-1E05-46B5-B1BA-82910D56B332}
 		{767F3868-11D0-445D-9B86-F81C7FCEB6FA} = {01F231DE-4A65-435F-B4BB-77EE5221890C}
 		{2D07F149-106B-4644-9586-D6218F78D868} = {01F231DE-4A65-435F-B4BB-77EE5221890C}
+		{253348AD-C9C0-4162-A2ED-C6FF8730B275} = {A5291117-3001-498B-AC8B-E14F71F72570}
+		{C1CA8B7E-F8E6-40AB-A45B-5EBEF6996290} = {A5291117-3001-498B-AC8B-E14F71F72570}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {859FB3DF-C60A-46B1-82E5-90274905D1EF}

src/GuiApp/Avalonia/FileTime.GuiApp.Abstractions/Configuration/MainConfiguration.cs

@@ -59,6 +59,7 @@ public static class MainConfiguration
             new(EnterRapidTravelCommand.CommandName,new KeyConfig(Key.OemQuestion, shift: true)),
             //new CommandBindingConfiguration(ConfigCommand.FindByName, new[] { Key.F, Key.N }),
             //new CommandBindingConfiguration(ConfigCommand.FindByNameRegex, new[] { Key.F, Key.R }),
+            new(GoByFrequencyCommand.CommandName, Key.Z),
             new(GoToHomeCommand.CommandName, new[] { Key.G, Key.H }),
             new(GoToPathCommand.CommandName, new KeyConfig(Key.L, ctrl: true)),
             new(GoToPathCommand.CommandName, new[] { Key.G, Key.P }),

src/GuiApp/Avalonia/FileTime.GuiApp.App/App.axaml.cs

@@ -2,6 +2,7 @@ using Avalonia;
 using Avalonia.Controls.ApplicationLifetimes;
 using Avalonia.Markup.Xaml;
 using FileTime.App.DependencyInjection;
+using FileTime.App.FrequencyNavigation;
 using FileTime.GuiApp.Font;
 using FileTime.GuiApp.ViewModels;
 using FileTime.GuiApp.Views;
@@ -17,6 +18,7 @@ public partial class App : Application
         var configuration = Startup.CreateConfiguration();
         DI.ServiceProvider = DependencyInjection
             .RegisterDefaultServices()
+            .AddFrequencyNavigation()
             .AddConfiguration(configuration)
             .ConfigureFont(configuration)
             .RegisterLogging()

src/GuiApp/Avalonia/FileTime.GuiApp.App/FileTime.GuiApp.App.csproj

@@ -41,6 +41,7 @@
   <ItemGroup>
     <ProjectReference Include="..\..\..\AppCommon\FileTime.App.Core\FileTime.App.Core.csproj" />
     <ProjectReference Include="..\..\..\AppCommon\FileTime.App.DependencyInjection\FileTime.App.DependencyInjection.csproj" />
+    <ProjectReference Include="..\..\..\AppCommon\FileTime.App.FrequencyNavigation\FileTime.App.FrequencyNavigation.csproj" />
     <ProjectReference Include="..\FileTime.GuiApp.CustomImpl\FileTime.GuiApp.CustomImpl.csproj" />
     <ProjectReference Include="..\FileTime.GuiApp.Font\FileTime.GuiApp.Font.csproj" />
     <ProjectReference Include="..\FileTime.GuiApp\FileTime.GuiApp.csproj" />

src/GuiApp/Avalonia/FileTime.GuiApp/FileTime.GuiApp.csproj

@@ -39,6 +39,7 @@
 
   <ItemGroup>
     <ProjectReference Include="..\..\..\AppCommon\FileTime.App.Core.Abstraction\FileTime.App.Core.Abstraction.csproj" />
+    <ProjectReference Include="..\..\..\AppCommon\FileTime.App.FrequencyNavigation.Abstractions\FileTime.App.FrequencyNavigation.Abstractions.csproj" />
     <ProjectReference Include="..\..\..\Providers\FileTime.Providers.Local.Abstractions\FileTime.Providers.Local.Abstractions.csproj" />
     <ProjectReference Include="..\FileTime.GuiApp.Abstractions\FileTime.GuiApp.Abstractions.csproj" />
     <ProjectReference Include="..\FileTime.GuiApp.Font.Abstractions\FileTime.GuiApp.Font.Abstractions.csproj" />

src/GuiApp/Avalonia/FileTime.GuiApp/Services/ModalService.cs

@@ -1,20 +1,31 @@
 using DynamicData;
 using FileTime.App.Core.Services;
 using FileTime.App.Core.ViewModels;
+using Microsoft.Extensions.DependencyInjection;
 
 namespace FileTime.GuiApp.Services;
 
 public class ModalService : IModalService
 {
+    private readonly IServiceProvider _serviceProvider;
     private readonly SourceList<IModalViewModel> _openModals = new();
     public IObservable<IChangeSet<IModalViewModel>> OpenModals { get; }
 
-    public ModalService()
+    public ModalService(IServiceProvider serviceProvider)
     {
+        _serviceProvider = serviceProvider;
         OpenModals = _openModals.Connect().StartWithEmpty();
     }
 
     public void OpenModal(IModalViewModel modalToOpen) => _openModals.Add(modalToOpen);
 
     public void CloseModal(IModalViewModel modalToClose) => _openModals.Remove(modalToClose);
+    
+    public T OpenModal<T>() where T : IModalViewModel
+    {
+        var modal = _serviceProvider.GetRequiredService<T>();
+        OpenModal(modal);
+
+        return modal;
+    }
 }

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

@@ -3,6 +3,8 @@ using System.Reflection;
 using Avalonia.Input;
 using FileTime.App.Core.Services;
 using FileTime.App.Core.UserCommand;
+using FileTime.App.FrequencyNavigation.Services;
+using FileTime.App.FrequencyNavigation.ViewModels;
 using FileTime.Core.Models;
 using FileTime.Core.Timeline;
 using FileTime.GuiApp.Services;
@@ -24,6 +26,7 @@ namespace FileTime.GuiApp.ViewModels;
 [Inject(typeof(IDialogService), PropertyAccessModifier = AccessModifier.Public)]
 [Inject(typeof(ITimelessContentProvider), PropertyName = "_timelessContentProvider")]
 [Inject(typeof(IFontService), "_fontService")]
+[Inject(typeof(IFrequencyNavigationService), PropertyAccessModifier = AccessModifier.Public)]
 public partial class MainWindowViewModel : IMainWindowViewModelBase
 {
     public bool Loading => false;

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

@@ -0,0 +1,29 @@
+<UserControl
+    x:Class="FileTime.GuiApp.Views.FrequencyNavigation"
+    xmlns="https://github.com/avaloniaui"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+    xmlns:viewModels="clr-namespace:FileTime.App.FrequencyNavigation.ViewModels;assembly=FileTime.App.FrequencyNavigation.Abstractions"
+    d:DesignHeight="450"
+    d:DesignWidth="800"
+    x:CompileBindings="True"
+    x:DataType="viewModels:IFrequencyNavigationViewModel"
+    mc:Ignorable="d">
+    <Grid RowDefinitions="Auto,*">
+        <TextBox
+            KeyDown="Search_OnKeyDown"
+            Text="{Binding SearchText, Mode=TwoWay}" />
+        <ItemsRepeater
+            Grid.Row="1"
+            Items="{Binding FilteredMatches}">
+            <ItemsRepeater.ItemTemplate>
+                <DataTemplate x:DataType="x:String">
+                    <Grid Margin="5">
+                        <TextBlock Text="{Binding}" />
+                    </Grid>
+                </DataTemplate>
+            </ItemsRepeater.ItemTemplate>
+        </ItemsRepeater>
+    </Grid>
+</UserControl>

src/GuiApp/Avalonia/FileTime.GuiApp/Views/FrequencyNavigation.axaml.cs

@@ -0,0 +1,30 @@
+using Avalonia;
+using Avalonia.Controls;
+using Avalonia.Input;
+using Avalonia.Markup.Xaml;
+using FileTime.App.FrequencyNavigation.ViewModels;
+
+namespace FileTime.GuiApp.Views;
+
+public partial class FrequencyNavigation : UserControl
+{
+    public FrequencyNavigation()
+    {
+        InitializeComponent();
+    }
+
+    private void InitializeComponent()
+    {
+        AvaloniaXamlLoader.Load(this);
+    }
+
+    private void Search_OnKeyDown(object? sender, KeyEventArgs e)
+    {
+        if (DataContext is not IFrequencyNavigationViewModel viewModel) return;
+        
+        if (e.Key == Key.Escape)
+        {
+            viewModel.Close();
+        }
+    }
+}

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

@@ -709,6 +709,15 @@
                 </Border>
             </Border>
 
+            <Border
+                DataContext="{Binding FrequencyNavigationService.CurrentModal}"
+                Margin="100"
+                HorizontalAlignment="Stretch"
+                VerticalAlignment="Stretch"
+                Background="{DynamicResource BarelyTransparentBackgroundColor}"
+                IsVisible="{Binding ShowWindow^, FallbackValue=False}">
+                <local:FrequencyNavigation />
+            </Border>
         </Grid>
 
         <Grid IsVisible="{Binding Loading}">

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

@@ -76,11 +76,11 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
         {
             if ((path?.Length ?? 0) == 0)
             {
-                return Task.FromResult((IItem)this);
+                return Task.FromResult((IItem) this);
             }
             else if (Directory.Exists(path))
             {
-                return Task.FromResult((IItem)DirectoryToContainer(
+                return Task.FromResult((IItem) DirectoryToContainer(
                     new DirectoryInfo(path!.TrimEnd(Path.DirectorySeparatorChar) + Path.DirectorySeparatorChar),
                     pointInTime,
                     !itemInitializationSettings.SkipChildInitialization)
@@ -88,7 +88,7 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
             }
             else if (File.Exists(path))
             {
-                return Task.FromResult((IItem)FileToElement(new FileInfo(path), pointInTime));
+                return Task.FromResult((IItem) FileToElement(new FileInfo(path), pointInTime));
             }
 
             var type = forceResolvePathType switch
@@ -120,10 +120,10 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
         return forceResolvePathType switch
         {
             AbsolutePathType.Container => Task.FromResult(
-                (IItem)CreateEmptyContainer(
+                (IItem) CreateEmptyContainer(
                     nativePath,
                     pointInTime,
-                    Observable.Return(new List<Exception>() { innerException })
+                    new List<Exception>() {innerException}
                 )
             ),
             AbsolutePathType.Element => Task.FromResult(CreateEmptyElement(nativePath)),
@@ -135,9 +135,14 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
 
     private Container CreateEmptyContainer(NativePath nativePath,
         PointInTime pointInTime,
-        IObservable<IEnumerable<Exception>>? exceptions = null)
+        IEnumerable<Exception>? initialExceptions = null)
     {
-        var nonNullExceptions = exceptions ?? Observable.Return(Enumerable.Empty<Exception>());
+        var exceptions = new SourceList<Exception>();
+        if (initialExceptions is not null)
+        {
+            exceptions.AddRange(initialExceptions);
+        }
+
         var name = nativePath.Path.Split(Path.DirectorySeparatorChar).LastOrDefault() ?? "???";
         var fullName = GetFullName(nativePath);
 
@@ -166,7 +171,7 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
             this,
             true,
             pointInTime,
-            nonNullExceptions,
+            exceptions.Connect(),
             new ExtensionCollection().AsReadOnly(),
             Observable.Return<IObservable<IChangeSet<AbsolutePath, string>>?>(null)
         );
@@ -202,7 +207,7 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
                     pointInTime,
                     parentFullName,
                     AbsolutePathType.Container);
-        var exceptions = new BehaviorSubject<IEnumerable<Exception>>(Enumerable.Empty<Exception>());
+        var exceptions = new SourceList<Exception>();
 
         var children = new SourceCache<AbsolutePath, string>(i => i.Path.Path);
 
@@ -221,14 +226,14 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
             this,
             true,
             pointInTime,
-            exceptions,
+            exceptions.Connect(),
             new ExtensionCollection().AsReadOnly(),
             //Observable.FromAsync(async () => await Task.Run(InitChildrenHelper)
             //Observable.Return(InitChildren())
             Observable.Return(children.Connect())
         );
 
-        Task.Run(() => LoadChildren(container, directoryInfo, children, pointInTime));
+        Task.Run(() => LoadChildren(container, directoryInfo, children, pointInTime, exceptions));
 
         return container;
 
@@ -241,25 +246,25 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
                 var items = GetItemsByContainer(directoryInfo, pointInTime);
                 var result = new SourceCache<AbsolutePath, string>(i => i.Path.Path);
 
-                if (items.Count == 0) return (IObservable<IChangeSet<AbsolutePath, string>>?)result.Connect().StartWithEmpty();
+                if (items.Count == 0) return (IObservable<IChangeSet<AbsolutePath, string>>?) result.Connect().StartWithEmpty();
 
                 result.AddOrUpdate(items);
-                return (IObservable<IChangeSet<AbsolutePath, string>>?)result.Connect();
+                return (IObservable<IChangeSet<AbsolutePath, string>>?) result.Connect();
             }
             catch (Exception e)
             {
-                exceptions.OnNext(new List<Exception> { e });
+                exceptions.Add(e);
             }
 
             return null;
         }
     }
 
-    private void LoadChildren(
+    private void LoadChildren(Container container,
-        Container container,
         DirectoryInfo directoryInfo,
         SourceCache<AbsolutePath, string> children,
-        PointInTime pointInTime)
+        PointInTime pointInTime,
+        SourceList<Exception> exceptions)
     {
         var lockobj = new object();
         var loadingIndicatorCancellation = new CancellationTokenSource();
@@ -274,6 +279,8 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
         }
 
         void LoadChildren()
+        {
+            try
             {
                 foreach (var directory in directoryInfo.EnumerateDirectories())
                 {
@@ -289,6 +296,11 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
                     children.AddOrUpdate(absolutePath);
                 }
             }
+            catch (Exception e)
+            {
+                exceptions.Add(e);
+            }
+        }
 
         async Task DelayedLoadingIndicator()
         {
@@ -297,7 +309,9 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
             {
                 await Task.Delay(500, token);
             }
-            catch { }
+            catch
+            {
+            }
 
             lock (lockobj)
             {
@@ -345,7 +359,7 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
             GetFileAttributes(fileInfo),
             this,
             pointInTime,
-            Observable.Return(Enumerable.Empty<Exception>()),
+            new SourceList<Exception>().Connect(),
             extensions.AsReadOnly()
         );
     }
@@ -385,7 +399,7 @@ public sealed partial class LocalContentProvider : ContentProviderBase, ILocalCo
         var size = maxLength ?? realFileSize switch
         {
             > int.MaxValue => int.MaxValue,
-            _ => (int)realFileSize
+            _ => (int) realFileSize
         };
         var buffer = new byte[size];
         await reader.ReadAsync(buffer.AsMemory(0, size), cancellationToken);