Allow sharting of themes and layouts via mod.io

src/DesktopMagic/DataContexts/MainWindowDataContext.cs

@@ -18,6 +18,7 @@ internal class MainWindowDataContext : INotifyPropertyChanged
     private string? selectedLayoutName;
 
     private bool isLoading = true;
+    private bool isSharing;
     private string? pluginsSearchText;
 
     public string Title =>
@@ -29,6 +30,19 @@ internal class MainWindowDataContext : INotifyPropertyChanged
 
     public string AppName => App.AppName;
 
+    /// <summary>
+    /// Whether a layout or theme is currently being uploaded to mod.io.
+    /// </summary>
+    public bool IsSharing
+    {
+        get => isSharing;
+        set
+        {
+            isSharing = value;
+            OnPropertyChanged();
+        }
+    }
+
     public DesktopMagicSettings Settings
     {
         get => settings;

src/DesktopMagic/DataContexts/PluginManagerDataContext.cs

@@ -17,9 +17,38 @@ internal class PluginManagerDataContext : INotifyPropertyChanged
     private bool isLoading = true;
     private bool isSearching;
     private bool isAuthenticated = false;
+    private ModCategory category = ModCategory.Plugins;
+
     public ObservableCollection<PluginEntryDataContext> AllPlugins { get; } = [];
     public ObservableCollection<PluginEntryDataContext> InstalledPlugins { get; } = [];
 
+    // Layouts or themes, depending on the selected category.
+    public ObservableCollection<PluginEntryDataContext> AllShared { get; } = [];
+    public ObservableCollection<PluginEntryDataContext> InstalledShared { get; } = [];
+
+    public ModCategory Category
+    {
+        get => category;
+        set
+        {
+            category = value;
+            OnPropertyChanged();
+            OnPropertyChanged(nameof(CategoryIndex));
+            OnPropertyChanged(nameof(ShownAll));
+            OnPropertyChanged(nameof(ShownInstalled));
+        }
+    }
+
+    public int CategoryIndex
+    {
+        get => (int)category;
+        set => Category = (ModCategory)value;
+    }
+
+    public ObservableCollection<PluginEntryDataContext> ShownAll => category == ModCategory.Plugins ? AllPlugins : AllShared;
+
+    public ObservableCollection<PluginEntryDataContext> ShownInstalled => category == ModCategory.Plugins ? InstalledPlugins : InstalledShared;
+
     public bool IsLoading
     {
         get => isLoading;
@@ -97,4 +126,11 @@ internal class PluginManagerDataContext : INotifyPropertyChanged
     {
         PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));
     }
-}
+}
+
+internal enum ModCategory
+{
+    Plugins,
+    Layouts,
+    Themes
+}

src/DesktopMagic/DesktopMagic.csproj

@@ -49,7 +49,6 @@
         <PackageReference Include="Interop.IWshRuntimeLibrary" Version="1.0.1" />
         <PackageReference Include="Ical.Net" Version="4.3.1" />
         <PackageReference Include="Microsoft.Web.WebView2" Version="1.0.3650.58" />
-        <PackageReference Include="Modio" Version="1.0.0" />
         <PackageReference Include="NAudio" Version="2.2.1" />
         <PackageReference Include="SkiaSharp" Version="4.148.0" />
         <PackageReference Include="System.Management" Version="8.0.0" />
@@ -60,6 +59,7 @@
 
     <ItemGroup>
         <ProjectReference Include="..\DesktopMagicPluginAPI\DesktopMagic.Api.csproj" />
+        <ProjectReference Include="..\..\lib\modio.net\Modio\Modio.csproj" />
     </ItemGroup>
 
     <ItemGroup>

src/DesktopMagic/Helpers/ModIoService.cs

@@ -0,0 +1,725 @@
+using DesktopMagic.Dialogs;
+using DesktopMagic.Plugins;
+using DesktopMagic.Settings;
+
+using Modio;
+using Modio.Filters;
+using Modio.Models;
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.IO;
+using System.IO.Compression;
+using System.Linq;
+using System.Net.Http;
+using System.Text.Json.Nodes;
+using System.Threading.Tasks;
+using System.Windows;
+
+using File = System.IO.File;
+using Path = System.IO.Path;
+
+namespace DesktopMagic.Helpers;
+
+/// <summary>
+/// Shared mod.io access: authentication and sharing/syncing of layouts and themes.
+/// </summary>
+internal static class ModIoService
+{
+    public const uint GameId = 5665;
+    public const string ApiKey = "88e6ea774c3a502b06114e7fee0829ac";
+
+    private const string Source = "ModIo";
+    private const int MaxSummaryLength = 250;
+
+    private static readonly HttpClient httpClient = new();
+    private static (string Token, uint UserId)? currentUser;
+
+    public static bool IsAuthenticated => AppSettings.ModIoAccessToken is not null;
+
+    private static DesktopMagicSettings AppSettings => Manager.Instance.Settings;
+
+    public static Client CreateClient()
+    {
+        Client.Builder builder = CreateBuilder();
+
+        if (AppSettings.ModIoAccessToken is string token)
+        {
+            _ = builder.WithToken(token);
+        }
+
+        return builder.Build();
+    }
+
+    /// <summary>
+    /// The shared api.mod.io host is deprecated, requests have to go to the game specific host.
+    /// </summary>
+    private static Client.Builder CreateBuilder()
+    {
+        return Client.GetBuilder(ApiKey).WithGameHost(GameId);
+    }
+
+    /// <summary>
+    /// Whether the mod is a plugin (as opposed to a shared layout or theme).
+    /// </summary>
+    public static bool IsPluginMod(Mod mod)
+    {
+        return !mod.Tags.Any(tag => tag.Name is SharePackage.LayoutTag or SharePackage.ThemeTag);
+    }
+
+    /// <summary>
+    /// Runs the e-mail security code login. Returns false when cancelled.
+    /// </summary>
+    public static async Task<bool> LogInAsync(Window? owner, string title)
+    {
+        App.Logger.LogInfo("Starting mod.io authentication", source: Source);
+        Client client = CreateBuilder().Build();
+
+        InputDialog inputDialog = new(GetString("enterModIoEmail"), title)
+        {
+            Owner = owner,
+        };
+
+        if (inputDialog.ShowDialog() != true)
+        {
+            App.Logger.LogInfo("Authentication cancelled by user", source: Source);
+            return false;
+        }
+
+        await client.Auth.RequestCode(ApiKey, inputDialog.ResponseText);
+
+        inputDialog = new(GetString("enterModIoAccessToken"), title)
+        {
+            Owner = owner,
+        };
+
+        if (inputDialog.ShowDialog() != true)
+        {
+            App.Logger.LogInfo("Authentication cancelled by user", source: Source);
+            return false;
+        }
+
+        AccessToken accessToken = await client.Auth.SecurityCode(ApiKey, inputDialog.ResponseText);
+        if (accessToken.Value is null)
+        {
+            return false;
+        }
+
+        AppSettings.ModIoAccessToken = accessToken.Value;
+        Manager.Instance.SaveSettings();
+        App.Logger.LogInfo("Successfully authenticated with mod.io", source: Source);
+        return true;
+    }
+
+    public static void LogOut()
+    {
+        App.Logger.LogInfo("Logging out from mod.io", source: Source);
+        AppSettings.ModIoAccessToken = null;
+        currentUser = null;
+        Manager.Instance.SaveSettings();
+    }
+
+    /// <summary>
+    /// Compares the local content with the last published or downloaded version.
+    /// </summary>
+    public static void RefreshShareState(IModIoShareable item)
+    {
+        item.ShareState = item.ModIo switch
+        {
+            null => ModIoShareState.NotShared,
+            { IsOwner: false } => ModIoShareState.NotOwner,
+            { PublishedHash: string hash } when hash == SharePackage.Build(item).Hash => ModIoShareState.UpToDate,
+            _ => ModIoShareState.Modified,
+        };
+    }
+
+    /// <summary>
+    /// Publishes the item as a new mod, uploads a new version of the linked mod, or opens the mod page when nothing changed.
+    /// </summary>
+    /// <param name="setBusy">Shows or hides the caller's waiting overlay while the upload runs.</param>
+    public static async Task ShareAsync(IModIoShareable item, Window? owner, Action<bool> setBusy)
+    {
+        if (item is Layout { Name: Manager.EmptyLayoutName })
+        {
+            await ShowMessageAsync(GetString("cannotShareEmptyLayout"));
+            return;
+        }
+
+        RefreshShareState(item);
+
+        if (item.ShareState == ModIoShareState.UpToDate)
+        {
+            OpenProfile(item.ModIo?.ProfileUri);
+            return;
+        }
+
+        if (!IsAuthenticated && !await LogInAsync(owner, App.AppName))
+        {
+            return;
+        }
+
+        SharePackage.Package package = SharePackage.Build(item);
+        bool isUpdate = item.ModIo is { IsOwner: true };
+
+        string? summary = null;
+        string? changelog = null;
+
+        if (isUpdate)
+        {
+            InputDialog changelogDialog = new(GetString("enterModIoChangelog")) { Owner = owner };
+            if (changelogDialog.ShowDialog() != true)
+            {
+                return;
+            }
+
+            changelog = changelogDialog.ResponseText.Trim();
+        }
+        else
+        {
+            string warning = GetString(item is Layout ? "modIoShareLayoutWarning" : "modIoShareThemeWarning");
+            if (package.LocalPlugins.Count > 0)
+            {
+                warning += Environment.NewLine + Environment.NewLine + string.Format(GetString("modIoLocalPluginsWarning"), string.Join(", ", package.LocalPlugins));
+            }
+
+            if (!await ConfirmAsync(warning, GetString("shareOnModIo")))
+            {
+                return;
+            }
+
+            InputDialog summaryDialog = new(GetString("enterModIoSummary")) { Owner = owner };
+            if (summaryDialog.ShowDialog() != true)
+            {
+                return;
+            }
+
+            summary = summaryDialog.ResponseText.Trim();
+            if (string.IsNullOrWhiteSpace(summary))
+            {
+                summary = item.Name;
+            }
+
+            if (summary.Length > MaxSummaryLength)
+            {
+                summary = summary[..MaxSummaryLength];
+            }
+        }
+
+        string workingDirectory = Path.Combine(Path.GetTempPath(), App.AppName, Guid.NewGuid().ToString());
+        setBusy(true);
+
+        try
+        {
+            _ = Directory.CreateDirectory(workingDirectory);
+
+            string contentDirectory = Path.Combine(workingDirectory, "content");
+            _ = Directory.CreateDirectory(contentDirectory);
+            await File.WriteAllTextAsync(Path.Combine(contentDirectory, SharePackage.ContentFileName), package.Json.ToJsonString());
+
+            string zipPath = Path.Combine(workingDirectory, "content.zip");
+            ZipFile.CreateFromDirectory(contentDirectory, zipPath);
+
+            string logoPath = Path.Combine(workingDirectory, "logo.png");
+            SharePreviewRenderer.Render(item, logoPath);
+
+            Client client = CreateClient();
+            ModIoLink link;
+
+            if (isUpdate)
+            {
+                link = item.ModIo!;
+            }
+            else
+            {
+                App.Logger.LogInfo($"Creating mod.io mod for \"{item.Name}\"", source: Source);
+                NewMod newMod = new(item.Name, summary!, new FileInfo(logoPath))
+                {
+                    Visible = Modio.Models.Visibility.Public,
+                };
+                newMod.Tags.Add(SharePackage.GetTag(item));
+
+                Mod mod = await client.Games[GameId].Mods.Add(newMod);
+
+                // A downloaded item shared as a new mod no longer follows the original, which would otherwise be downloaded again.
+                if (item.ModIo is { IsOwner: false } originalLink)
+                {
+                    await UnsubscribeAsync(originalLink.ModId);
+                }
+
+                // Save the link right away, so a failed upload is retried on the same mod instead of creating another one.
+                link = new ModIoLink
+                {
+                    ModId = mod.Id,
+                    IsOwner = true,
+                    ProfileUri = mod.ProfileUrl,
+                };
+                item.ModIo = link;
+                Manager.Instance.SaveSettings();
+            }
+
+            App.Logger.LogInfo($"Uploading new version of \"{item.Name}\" (mod {link.ModId})", source: Source);
+            Modio.Models.File modfile = await client.Games[GameId].Mods[link.ModId].Files.Add(new NewFile(new FileInfo(zipPath))
+            {
+                Version = DateTime.UtcNow.ToString("yyyy.MM.dd.HHmm"),
+                Changelog = string.IsNullOrWhiteSpace(changelog) ? null : changelog,
+                Active = true,
+            }, new UploadOptions());
+
+            link.ModfileId = modfile.Id;
+            link.PublishedHash = package.Hash;
+            Manager.Instance.SaveSettings();
+
+            if (isUpdate)
+            {
+                await TryUpdateLogo(client, link.ModId, logoPath);
+            }
+
+            if (item is Layout)
+            {
+                await TryUpdateDependencies(client, link.ModId, package.RequiredPlugins);
+            }
+
+            RefreshShareState(item);
+            App.Logger.LogInfo($"Published \"{item.Name}\" on mod.io", source: Source);
+
+            setBusy(false);
+            if (await ConfirmAsync(string.Format(GetString(isUpdate ? "modIoUpdateSuccess" : "modIoShareSuccess"), item.Name), GetString("open"), GetString("close")))
+            {
+                OpenProfile(link.ProfileUri);
+            }
+        }
+        catch (UnauthorizedException ex)
+        {
+            App.Logger.LogError($"Sharing \"{item.Name}\" failed, not authorized: {ex.Message}", source: Source);
+            LogOut();
+            setBusy(false);
+            await ShowMessageAsync(GetString("modIoSessionExpired"));
+        }
+        catch (Exception ex)
+        {
+            App.Logger.LogError($"Sharing \"{item.Name}\" failed: {ex.Message}", source: Source);
+            setBusy(false);
+            await ShowMessageAsync(string.Format(GetString("modIoShareFailed"), ex.Message));
+        }
+        finally
+        {
+            setBusy(false);
+            RefreshShareState(item);
+            TryDeleteDirectory(workingDirectory);
+        }
+    }
+
+    /// <summary>
+    /// Unsubscribes from the mod an item is linked to, so deleting it locally does not bring it back on the next sync.
+    /// </summary>
+    public static async Task UnsubscribeAsync(IModIoShareable item)
+    {
+        if (item.ModIo is not null)
+        {
+            await UnsubscribeAsync(item.ModIo.ModId);
+        }
+    }
+
+    private static async Task UnsubscribeAsync(uint modId)
+    {
+        if (!IsAuthenticated)
+        {
+            return;
+        }
+
+        try
+        {
+            await CreateClient().Games[GameId].Mods.Unsubscribe(modId);
+            App.Logger.LogInfo($"Unsubscribed from mod {modId}", source: Source);
+        }
+        catch (Exception ex)
+        {
+            App.Logger.LogError($"Failed to unsubscribe from mod {modId}: {ex.Message}", source: Source);
+        }
+    }
+
+    /// <summary>
+    /// Subscribes to the mods of downloaded layouts and themes, e.g. after logging in,
+    /// so the subscription sync keeps them instead of treating them as unsubscribed.
+    /// </summary>
+    public static async Task SubscribeToLinkedItemsAsync()
+    {
+        if (!IsAuthenticated)
+        {
+            return;
+        }
+
+        Client client = CreateClient();
+
+        foreach (ModIoLink link in GetSharedItems().Select(item => item.ModIo).OfType<ModIoLink>().Where(link => !link.IsOwner).ToList())
+        {
+            try
+            {
+                await client.Games[GameId].Mods.Subscribe(link.ModId);
+                App.Logger.LogInfo($"Subscribed to mod {link.ModId}", source: Source);
+            }
+            catch (Exception ex)
+            {
+                App.Logger.LogError($"Failed to subscribe to mod {link.ModId}: {ex.Message}", source: Source);
+            }
+        }
+    }
+
+    public static IEnumerable<IModIoShareable> GetSharedItems()
+    {
+        DesktopMagicSettings settings = AppSettings;
+        return settings.Layouts.Cast<IModIoShareable>().Concat(settings.Themes);
+    }
+
+    public static IModIoShareable? FindLinkedItem(uint modId)
+    {
+        return GetSharedItems().FirstOrDefault(item => item.ModIo?.ModId == modId);
+    }
+
+    /// <summary>
+    /// Downloads a layout or theme from mod.io and subscribes to it when logged in.
+    /// </summary>
+    /// <param name="ensurePluginInstalled">Installs the mod.io plugin with the given ID if it is missing.</param>
+    /// <returns>Whether the item was installed.</returns>
+    public static async Task<bool> InstallAsync(Mod mod, Func<uint, Task> ensurePluginInstalled)
+    {
+        try
+        {
+            if (!await ApplyLatestVersionAsync(mod, FindLinkedItem(mod.Id), ensurePluginInstalled))
+            {
+                return false;
+            }
+
+            if (IsAuthenticated)
+            {
+                try
+                {
+                    await CreateClient().Games[GameId].Mods.Subscribe(mod.Id);
+                    App.Logger.LogInfo($"Subscribed to mod {mod.Id}", source: Source);
+                }
+                catch (Exception ex)
+                {
+                    App.Logger.LogError($"Failed to subscribe to mod {mod.Id}: {ex.Message}", source: Source);
+                }
+            }
+
+            Manager.Instance.SaveSettings();
+            return true;
+        }
+        catch (Exception ex)
+        {
+            App.Logger.LogError($"Failed to install \"{mod.Name}\" (mod {mod.Id}): {ex.Message}", source: Source);
+            await ShowMessageAsync(string.Format(GetString("modIoInstallFailed"), mod.Name, ex.Message));
+            return false;
+        }
+    }
+
+    /// <summary>
+    /// Updates a linked layout or theme when mod.io has a newer version.
+    /// </summary>
+    /// <returns>Whether the item changed.</returns>
+    public static async Task<bool> UpdateAsync(IModIoShareable item, Mod mod, Func<uint, Task> ensurePluginInstalled)
+    {
+        try
+        {
+            if (!await ApplyLatestVersionAsync(mod, item, ensurePluginInstalled))
+            {
+                return false;
+            }
+
+            Manager.Instance.SaveSettings();
+            return true;
+        }
+        catch (Exception ex)
+        {
+            App.Logger.LogError($"Failed to update \"{item.Name}\" (mod {mod.Id}): {ex.Message}", source: Source);
+            return false;
+        }
+    }
+
+    /// <summary>
+    /// Deletes a layout or theme locally after confirmation and unsubscribes from its mod.
+    /// The mod itself stays on mod.io.
+    /// </summary>
+    /// <returns>Whether the item was removed.</returns>
+    public static async Task<bool> RemoveAsync(IModIoShareable item)
+    {
+        DesktopMagicSettings settings = AppSettings;
+
+        string? blocker = item switch
+        {
+            Layout { Name: Manager.EmptyLayoutName } => "cannotDeleteEmptyLayout",
+            Layout when settings.Layouts.Count <= 1 => "cannotDeleteLastLayout",
+            Theme when settings.Themes.Count <= 1 => "cannotDeleteLastTheme",
+            _ => null
+        };
+
+        if (blocker is not null)
+        {
+            await ShowMessageAsync(GetString(blocker));
+            return false;
+        }
+
+        if (!await ConfirmAsync(GetString(item is Layout ? "confirmDeleteLayout" : "confirmDeleteTheme"), "Yes", "No"))
+        {
+            return false;
+        }
+
+        await UnsubscribeAsync(item);
+
+        switch (item)
+        {
+            case Layout layout:
+                Manager.Instance.RemoveLayout(layout);
+                break;
+
+            case Theme theme:
+                _ = settings.Themes.Remove(theme);
+                Manager.Instance.SaveSettings();
+                break;
+        }
+
+        App.Logger.LogInfo($"Removed \"{item.Name}\"", source: Source);
+        return true;
+    }
+
+    /// <summary>
+    /// Downloads subscribed layouts and themes that are new or have a newer version on mod.io.
+    /// </summary>
+    /// <param name="subscriptions">The user's subscribed mods for this game.</param>
+    /// <param name="ensurePluginInstalled">Installs the mod.io plugin with the given ID if it is missing.</param>
+    /// <returns>Whether any layout or theme changed.</returns>
+    public static async Task<bool> SyncSubscriptionsAsync(IReadOnlyList<Mod> subscriptions, Func<uint, Task> ensurePluginInstalled)
+    {
+        if (!IsAuthenticated)
+        {
+            return false;
+        }
+
+        bool changed = false;
+
+        List<Mod> sharedMods = subscriptions.Where(mod => !IsPluginMod(mod)).ToList();
+        App.Logger.LogInfo($"Found {sharedMods.Count} subscribed layouts and themes on mod.io", source: Source);
+
+        foreach (Mod mod in sharedMods)
+        {
+            try
+            {
+                changed |= await ApplyLatestVersionAsync(mod, FindLinkedItem(mod.Id), ensurePluginInstalled);
+            }
+            catch (Exception ex)
+            {
+                App.Logger.LogError($"Failed to install \"{mod.Name}\" (mod {mod.Id}): {ex.Message}", source: Source);
+            }
+        }
+
+        // Downloaded items whose subscription was removed on mod.io stay as local copies.
+        foreach (IModIoShareable item in GetSharedItems().Where(item => item.ModIo is { IsOwner: false } && !subscriptions.Any(mod => mod.Id == item.ModIo.ModId)).ToList())
+        {
+            App.Logger.LogInfo($"\"{item.Name}\" is no longer subscribed, keeping it as a local copy", source: Source);
+            item.ModIo = null;
+            RefreshShareState(item);
+            changed = true;
+        }
+
+        if (changed)
+        {
+            Manager.Instance.SaveSettings();
+        }
+
+        return changed;
+    }
+
+    /// <summary>
+    /// Downloads the current version of the mod into a new item, or into <paramref name="local"/> when it is outdated.
+    /// Asks before overwriting local changes. Throws when the download or import fails.
+    /// </summary>
+    /// <returns>Whether anything changed.</returns>
+    private static async Task<bool> ApplyLatestVersionAsync(Mod mod, IModIoShareable? local, Func<uint, Task> ensurePluginInstalled)
+    {
+        if (mod.Modfile?.Download?.BinaryUrl is null)
+        {
+            throw new InvalidOperationException("The mod has no file to download.");
+        }
+
+        if (local?.ModIo?.ModfileId == mod.Modfile.Id)
+        {
+            return false;
+        }
+
+        if (local?.ModIo is ModIoLink localLink && localLink.PublishedHash != SharePackage.Build(local).Hash)
+        {
+            bool overwrite = await ConfirmAsync(string.Format(GetString("modIoUpdateConflict"), local.Name), GetString("overwrite"), GetString("keepMine"));
+
+            if (!overwrite)
+            {
+                App.Logger.LogInfo($"Keeping local changes of \"{local.Name}\" instead of updating to mod {mod.Id} version {mod.Modfile.Id}", source: Source);
+
+                if (localLink.IsOwner)
+                {
+                    // The owner can publish their version over the remote one.
+                    localLink.ModfileId = mod.Modfile.Id;
+                }
+                else
+                {
+                    // Detach the local copy so it is no longer replaced by updates.
+                    await UnsubscribeAsync(local);
+                    local.ModIo = null;
+                }
+
+                return true;
+            }
+        }
+
+        App.Logger.LogInfo($"Downloading \"{mod.Name}\" (mod {mod.Id}, version {mod.Modfile.Id})", source: Source);
+        JsonObject content = await DownloadContentAsync(mod.Modfile.Download.BinaryUrl);
+
+        foreach (uint pluginId in SharePackage.GetRequiredPlugins(content).Where(id => !Manager.Instance.Plugins.ContainsKey(id)))
+        {
+            await ensurePluginInstalled(pluginId);
+        }
+
+        uint? userId = IsAuthenticated ? await GetCurrentUserIdAsync(CreateClient()) : null;
+
+        IModIoShareable item = SharePackage.Apply(content, local);
+        item.ModIo = new ModIoLink
+        {
+            ModId = mod.Id,
+            ModfileId = mod.Modfile.Id,
+            IsOwner = userId is not null && mod.SubmittedBy?.Id == userId,
+            ProfileUri = mod.ProfileUrl,
+        };
+        item.ModIo.PublishedHash = SharePackage.Build(item).Hash;
+        RefreshShareState(item);
+
+        App.Logger.LogInfo($"Installed \"{item.Name}\" from mod.io", source: Source);
+        return true;
+    }
+
+    private static async Task<JsonObject> DownloadContentAsync(Uri url)
+    {
+        using MemoryStream zipStream = new();
+        using (Stream download = await httpClient.GetStreamAsync(url))
+        {
+            await download.CopyToAsync(zipStream);
+        }
+
+        zipStream.Position = 0;
+        using ZipArchive archive = new(zipStream, ZipArchiveMode.Read);
+        ZipArchiveEntry entry = archive.GetEntry(SharePackage.ContentFileName) ?? throw new FormatException($"The download does not contain \"{SharePackage.ContentFileName}\".");
+
+        using StreamReader reader = new(entry.Open());
+        return SharePackage.Parse(await reader.ReadToEndAsync());
+    }
+
+    private static async Task<uint> GetCurrentUserIdAsync(Client client)
+    {
+        string token = AppSettings.ModIoAccessToken ?? string.Empty;
+
+        if (currentUser is not { } user || user.Token != token)
+        {
+            User me = await client.User.GetCurrentUser();
+            user = (token, me.Id);
+            currentUser = user;
+        }
+
+        return user.UserId;
+    }
+
+    private static async Task TryUpdateLogo(Client client, uint modId, string logoPath)
+    {
+        try
+        {
+            await client.Games[GameId].Mods[modId].AddMedia(new NewModMedia { Logo = new FileInfo(logoPath) });
+        }
+        catch (Exception ex)
+        {
+            App.Logger.LogWarn($"Failed to update logo of mod {modId}: {ex.Message}", source: Source);
+        }
+    }
+
+    private static async Task TryUpdateDependencies(Client client, uint modId, IReadOnlyList<uint> requiredPlugins)
+    {
+        try
+        {
+            DependenciesClient dependencies = client.Games[GameId].Mods[modId].Dependencies;
+            List<uint> current = (await dependencies.Get(false)).Select(dependency => dependency.ModId).ToList();
+
+            List<uint> removed = current.Except(requiredPlugins).ToList();
+            List<uint> added = requiredPlugins.Except(current).ToList();
+
+            if (removed.Count > 0)
+            {
+                await dependencies.Delete(removed);
+            }
+
+            if (added.Count > 0)
+            {
+                await dependencies.Add(added);
+            }
+        }
+        catch (Exception ex)
+        {
+            App.Logger.LogWarn($"Failed to update dependencies of mod {modId}: {ex.Message}", source: Source);
+        }
+    }
+
+    private static void OpenProfile(Uri? profileUri)
+    {
+        if (profileUri is null)
+        {
+            return;
+        }
+
+        _ = Process.Start(new ProcessStartInfo
+        {
+            UseShellExecute = true,
+            FileName = profileUri.ToString()
+        });
+    }
+
+    private static void TryDeleteDirectory(string path)
+    {
+        try
+        {
+            if (Directory.Exists(path))
+            {
+                Directory.Delete(path, true);
+            }
+        }
+        catch (Exception ex)
+        {
+            App.Logger.LogWarn($"Failed to delete temporary directory {path}: {ex.Message}", source: Source);
+        }
+    }
+
+    private static async Task ShowMessageAsync(string content)
+    {
+        Wpf.Ui.Controls.MessageBox messageBox = new()
+        {
+            Title = App.AppName,
+            Content = content,
+            CloseButtonText = "Ok"
+        };
+        _ = await messageBox.ShowDialogAsync();
+    }
+
+    private static async Task<bool> ConfirmAsync(string content, string confirmText, string? cancelText = null)
+    {
+        Wpf.Ui.Controls.MessageBox messageBox = new()
+        {
+            Title = App.AppName,
+            Content = content,
+            PrimaryButtonText = confirmText,
+            CloseButtonText = cancelText ?? GetString("cancel"),
+        };
+
+        return await messageBox.ShowDialogAsync() == Wpf.Ui.Controls.MessageBoxResult.Primary;
+    }
+
+    private static string GetString(string key)
+    {
+        return App.LanguageDictionary[key] as string ?? key;
+    }
+}

src/DesktopMagic/Helpers/SharePackage.cs

@@ -0,0 +1,327 @@
+using DesktopMagic.Plugins;
+using DesktopMagic.Settings;
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Security.Cryptography;
+using System.Text;
+using System.Text.Json;
+using System.Text.Json.Nodes;
+
+namespace DesktopMagic.Helpers;
+
+/// <summary>
+/// Converts layouts and themes to and from the portable JSON content that is uploaded to mod.io.
+/// </summary>
+internal static class SharePackage
+{
+    public const int FormatVersion = 1;
+    public const string LayoutTag = "Layout";
+    public const string ThemeTag = "Theme";
+    public const string ContentFileName = "content.json";
+
+    private static readonly JsonSerializerOptions jsonOptions = new()
+    {
+        Converters = { new ColorJsonConverter() }
+    };
+
+    /// <param name="Json">The content written to <see cref="ContentFileName"/>.</param>
+    /// <param name="Hash">Hash of the shared content, used to detect local changes.</param>
+    /// <param name="RequiredPlugins">mod.io plugin IDs the layout uses.</param>
+    /// <param name="LocalPlugins">Names of locally developed plugins the layout uses, which others cannot install.</param>
+    public sealed record Package(JsonObject Json, string Hash, IReadOnlyList<uint> RequiredPlugins, IReadOnlyList<string> LocalPlugins);
+
+    public static string GetTag(IModIoShareable item) => item is Layout ? LayoutTag : ThemeTag;
+
+    public static Package Build(IModIoShareable item)
+    {
+        return item switch
+        {
+            Layout layout => BuildLayout(layout),
+            Theme theme => BuildTheme(theme),
+            _ => throw new ArgumentException($"Unsupported item type {item.GetType().Name}", nameof(item))
+        };
+    }
+
+    private static Package BuildTheme(Theme theme)
+    {
+        JsonObject root = new()
+        {
+            ["format"] = FormatVersion,
+            ["type"] = ThemeTag,
+            ["themes"] = new JsonArray(SerializeTheme(theme)),
+        };
+
+        return new Package(root, ComputeHash(root), [], []);
+    }
+
+    private static Package BuildLayout(Layout layout)
+    {
+        DesktopMagicSettings settings = Manager.Instance.Settings;
+        IReadOnlyDictionary<uint, InternalPluginData> installedPlugins = Manager.Instance.Plugins;
+
+        Layout copy = new(layout.Name)
+        {
+            ScreenAspectRatio = layout.ScreenAspectRatio,
+        };
+
+        List<string> themeNames = [layout.Theme.Name];
+        List<uint> requiredPlugins = [];
+        List<string> localPlugins = [];
+
+        // Only enabled widgets are shared. Disabled entries are just placeholders for every installed plugin.
+        foreach ((uint pluginId, PluginSettings pluginSettings) in layout.Plugins.Where(kvp => kvp.Value.Enabled).OrderBy(kvp => kvp.Key))
+        {
+            copy.Plugins[pluginId] = new PluginSettings
+            {
+                Enabled = true,
+                Position = pluginSettings.Position,
+                Size = pluginSettings.Size,
+                CurrentThemeName = pluginSettings.CurrentThemeName,
+                Settings = pluginSettings.Settings.Where(setting => setting.Shareable).ToList(),
+            };
+
+            if (pluginSettings.CurrentThemeName is not null && settings.Themes.Any(t => t.Name == pluginSettings.CurrentThemeName) && !themeNames.Contains(pluginSettings.CurrentThemeName))
+            {
+                themeNames.Add(pluginSettings.CurrentThemeName);
+            }
+
+            // Built-in plugins have no directory and are available everywhere.
+            if (installedPlugins.TryGetValue(pluginId, out InternalPluginData? pluginData) && !string.IsNullOrEmpty(pluginData.DirectoryPath))
+            {
+                if (pluginData.Metadata.IsLocalPlugin)
+                {
+                    localPlugins.Add(pluginData.Metadata.Name);
+                }
+                else
+                {
+                    requiredPlugins.Add(pluginId);
+                }
+            }
+        }
+
+        copy.CurrentThemeName = layout.Theme.Name;
+
+        JsonObject layoutNode = JsonSerializer.SerializeToNode(copy, jsonOptions)!.AsObject();
+        _ = layoutNode.Remove(nameof(Layout.ModIo));
+
+        JsonArray themesNode = [];
+        foreach (string themeName in themeNames)
+        {
+            Theme? theme = settings.Themes.FirstOrDefault(t => t.Name == themeName);
+            if (theme is not null)
+            {
+                themesNode.Add(SerializeTheme(theme));
+            }
+        }
+
+        JsonObject root = new()
+        {
+            ["format"] = FormatVersion,
+            ["type"] = LayoutTag,
+            ["layout"] = layoutNode,
+            ["themes"] = themesNode,
+        };
+
+        // Required plugins are derived from the layout and depend on what is currently loaded, so they are not part of the hash.
+        string hash = ComputeHash(root);
+        root["requiredPlugins"] = new JsonArray(requiredPlugins.Select(id => (JsonNode)id).ToArray());
+
+        return new Package(root, hash, requiredPlugins, localPlugins);
+    }
+
+    public static JsonObject Parse(string json)
+    {
+        JsonObject root = JsonNode.Parse(json)?.AsObject() ?? throw new FormatException("The downloaded content is empty.");
+
+        int format = root["format"]?.GetValue<int>() ?? 0;
+        if (format is < 1 or > FormatVersion)
+        {
+            throw new FormatException($"Unsupported content format {format}. Please update DesktopMagic.");
+        }
+
+        return root;
+    }
+
+    public static IReadOnlyList<uint> GetRequiredPlugins(JsonObject root)
+    {
+        return root["requiredPlugins"]?.AsArray().Select(node => node!.GetValue<uint>()).ToList() ?? [];
+    }
+
+    /// <summary>
+    /// Adds the downloaded content to the settings, or updates <paramref name="existing"/> with it.
+    /// </summary>
+    public static IModIoShareable Apply(JsonObject root, IModIoShareable? existing)
+    {
+        DesktopMagicSettings settings = Manager.Instance.Settings;
+        string type = root["type"]?.GetValue<string>() ?? string.Empty;
+
+        List<Theme> themes = root["themes"]?.AsArray()
+            .Select(node => node.Deserialize<Theme>(jsonOptions))
+            .OfType<Theme>()
+            .ToList() ?? [];
+
+        if (type == ThemeTag)
+        {
+            Theme incoming = themes.FirstOrDefault() ?? throw new FormatException("The downloaded theme is empty.");
+            incoming.ModIo = null;
+
+            if (existing is Theme existingTheme)
+            {
+                CopyThemeValues(incoming, existingTheme);
+                return existingTheme;
+            }
+
+            incoming.Name = GetUniqueName(incoming.Name, settings.Themes.Select(t => t.Name));
+            settings.Themes.Add(incoming);
+            return incoming;
+        }
+
+        if (type != LayoutTag)
+        {
+            throw new FormatException($"Unknown content type \"{type}\".");
+        }
+
+        JsonObject layoutNode = root["layout"]?.AsObject() ?? throw new FormatException("The downloaded layout is empty.");
+        Layout incomingLayout = layoutNode.Deserialize<Layout>(jsonOptions) ?? throw new FormatException("The downloaded layout is invalid.");
+        string layoutName = existing?.Name ?? GetUniqueName(incomingLayout.Name, settings.Layouts.Select(l => l.Name));
+
+        Dictionary<string, string> themeNameMap = [];
+        foreach (Theme theme in themes)
+        {
+            themeNameMap[theme.Name] = AddEmbeddedTheme(theme, layoutName);
+        }
+
+        // Read the raw name, the getter falls back to another theme when the name does not exist yet.
+        string? layoutThemeName = layoutNode[nameof(Layout.CurrentThemeName)]?.GetValue<string>();
+        string? mappedLayoutThemeName = layoutThemeName is not null && themeNameMap.TryGetValue(layoutThemeName, out string? mapped) ? mapped : layoutThemeName;
+
+        Layout target = existing as Layout ?? new Layout(layoutName);
+
+        Dictionary<uint, PluginSettings> plugins = [];
+        foreach ((uint pluginId, PluginSettings incomingPlugin) in incomingLayout.Plugins)
+        {
+            if (incomingPlugin.CurrentThemeName is not null && themeNameMap.TryGetValue(incomingPlugin.CurrentThemeName, out string? pluginThemeName))
+            {
+                incomingPlugin.CurrentThemeName = pluginThemeName;
+            }
+
+            // Keep values that are never shared (e.g. URLs or locations) and saved widget data from the local copy.
+            if (target.Plugins.TryGetValue(pluginId, out PluginSettings? localPlugin))
+            {
+                incomingPlugin.State = localPlugin.State;
+                incomingPlugin.Settings = [.. incomingPlugin.Settings, .. localPlugin.Settings.Where(local => !incomingPlugin.Settings.Exists(s => s.Id == local.Id))];
+            }
+
+            incomingPlugin.Owner = target;
+            plugins[pluginId] = incomingPlugin;
+        }
+
+        // Widgets the new version no longer uses are disabled, keeping their settings.
+        foreach ((uint pluginId, PluginSettings localPlugin) in target.Plugins.Where(kvp => !plugins.ContainsKey(kvp.Key)))
+        {
+            localPlugin.Enabled = false;
+            plugins[pluginId] = localPlugin;
+        }
+
+        target.ScreenAspectRatio = incomingLayout.ScreenAspectRatio;
+        target.Plugins = plugins;
+        target.CurrentThemeName = mappedLayoutThemeName;
+
+        if (existing is null)
+        {
+            settings.Layouts.Add(target);
+        }
+
+        return target;
+    }
+
+    /// <summary>
+    /// Adds a theme that is embedded in a layout and returns the local name it is available under.
+    /// </summary>
+    private static string AddEmbeddedTheme(Theme theme, string layoutName)
+    {
+        DesktopMagicSettings settings = Manager.Instance.Settings;
+        theme.ModIo = null;
+
+        Theme? sameName = settings.Themes.FirstOrDefault(t => t.Name == theme.Name);
+        if (sameName is null)
+        {
+            settings.Themes.Add(theme);
+            return theme.Name;
+        }
+
+        if (HasSameValues(sameName, theme))
+        {
+            return sameName.Name;
+        }
+
+        // A different theme with the same name exists (e.g. "Default"). Use a name tied to the layout,
+        // which later updates of the same layout overwrite instead of adding more copies.
+        string layoutThemeName = $"{theme.Name} ({layoutName})";
+        Theme? layoutTheme = settings.Themes.FirstOrDefault(t => t.Name == layoutThemeName);
+
+        if (layoutTheme is null)
+        {
+            theme.Name = layoutThemeName;
+            settings.Themes.Add(theme);
+        }
+        else
+        {
+            CopyThemeValues(theme, layoutTheme);
+        }
+
+        return layoutThemeName;
+    }
+
+    private static void CopyThemeValues(Theme source, Theme target)
+    {
+        target.PrimaryColor = source.PrimaryColor;
+        target.SecondaryColor = source.SecondaryColor;
+        target.BackgroundColor = source.BackgroundColor;
+        target.Font = source.Font;
+        target.CornerRadius = source.CornerRadius;
+        target.Margin = source.Margin;
+    }
+
+    private static bool HasSameValues(Theme a, Theme b)
+    {
+        JsonObject nodeA = SerializeTheme(a);
+        JsonObject nodeB = SerializeTheme(b);
+        _ = nodeA.Remove(nameof(Theme.Name));
+        _ = nodeB.Remove(nameof(Theme.Name));
+
+        return JsonNode.DeepEquals(nodeA, nodeB);
+    }
+
+    private static JsonObject SerializeTheme(Theme theme)
+    {
+        JsonObject node = JsonSerializer.SerializeToNode(theme, jsonOptions)!.AsObject();
+        _ = node.Remove(nameof(Theme.ModIo));
+        return node;
+    }
+
+    private static string GetUniqueName(string name, IEnumerable<string> existingNames)
+    {
+        HashSet<string> names = existingNames.ToHashSet();
+        if (!names.Contains(name))
+        {
+            return name;
+        }
+
+        int index = 2;
+        while (names.Contains($"{name} ({index})"))
+        {
+            index++;
+        }
+
+        return $"{name} ({index})";
+    }
+
+    private static string ComputeHash(JsonObject root)
+    {
+        byte[] hash = SHA256.HashData(Encoding.UTF8.GetBytes(root.ToJsonString()));
+        return Convert.ToHexString(hash);
+    }
+}

src/DesktopMagic/Helpers/SharePreviewRenderer.cs

@@ -0,0 +1,148 @@
+using DesktopMagic.Plugins;
+using DesktopMagic.Settings;
+
+using System;
+using System.Globalization;
+using System.IO;
+using System.Linq;
+using System.Windows;
+using System.Windows.Media;
+using System.Windows.Media.Imaging;
+
+using Point = System.Windows.Point;
+
+namespace DesktopMagic.Helpers;
+
+/// <summary>
+/// Renders the logo image used for layouts and themes on mod.io (mod.io requires one, at least 512x288).
+/// </summary>
+internal static class SharePreviewRenderer
+{
+    private const int Width = 1280;
+    private const int Height = 720;
+
+    private static readonly Color canvasColor = Color.FromRgb(0x1C, 0x1C, 0x24);
+    private static readonly Color screenColor = Color.FromRgb(0x2E, 0x2E, 0x3A);
+
+    public static void Render(IModIoShareable item, string path)
+    {
+        DrawingVisual visual = new();
+
+        using (DrawingContext context = visual.RenderOpen())
+        {
+            context.DrawRectangle(new SolidColorBrush(canvasColor), null, new Rect(0, 0, Width, Height));
+
+            switch (item)
+            {
+                case Layout layout:
+                    DrawLayout(context, layout);
+                    break;
+
+                case Theme theme:
+                    DrawTheme(context, theme);
+                    break;
+            }
+        }
+
+        RenderTargetBitmap bitmap = new(Width, Height, 96, 96, PixelFormats.Pbgra32);
+        bitmap.Render(visual);
+
+        PngBitmapEncoder encoder = new();
+        encoder.Frames.Add(BitmapFrame.Create(bitmap));
+
+        using FileStream stream = File.Create(path);
+        encoder.Save(stream);
+    }
+
+    private static void DrawLayout(DrawingContext context, Layout layout)
+    {
+        const double padding = 60;
+        double aspectRatio = layout.ScreenAspectRatio > 0 ? layout.ScreenAspectRatio : 16.0 / 9.0;
+
+        double availableWidth = Width - (padding * 2);
+        double availableHeight = Height - (padding * 2);
+        double screenWidth = Math.Min(availableWidth, availableHeight * aspectRatio);
+        double screenHeight = screenWidth / aspectRatio;
+
+        Rect screen = new((Width - screenWidth) / 2, (Height - screenHeight) / 2, screenWidth, screenHeight);
+        context.DrawRoundedRectangle(new SolidColorBrush(screenColor), null, screen, 12, 12);
+
+        foreach ((uint pluginId, PluginSettings pluginSettings) in layout.Plugins.Where(kvp => kvp.Value.Enabled))
+        {
+            Theme theme = pluginSettings.Theme;
+
+            Rect widget = new(
+                screen.X + (pluginSettings.Position.X * screen.Width),
+                screen.Y + (pluginSettings.Position.Y * screen.Height),
+                Math.Max(4, pluginSettings.Size.X * screen.Width),
+                Math.Max(4, pluginSettings.Size.Y * screen.Height));
+            widget.Intersect(screen);
+
+            if (widget.IsEmpty)
+            {
+                continue;
+            }
+
+            Color background = MultiColorConverter.ConvertToMediaColor(theme.BackgroundColor);
+            if (background.A < 0x30)
+            {
+                background = Color.FromArgb(0x30, 0xFF, 0xFF, 0xFF);
+            }
+
+            Color primary = MultiColorConverter.ConvertToMediaColor(theme.PrimaryColor);
+            double radius = Math.Min(theme.CornerRadius * screen.Width / 1920, Math.Min(widget.Width, widget.Height) / 2);
+
+            context.DrawRoundedRectangle(new SolidColorBrush(background), new Pen(new SolidColorBrush(primary), 2), widget, radius, radius);
+
+            string name = Manager.Instance.Plugins.TryGetValue(pluginId, out InternalPluginData? pluginData) ? pluginData.Metadata.Name : pluginSettings.Metadata.Name;
+            if (string.IsNullOrWhiteSpace(name))
+            {
+                continue;
+            }
+
+            FormattedText text = CreateText(name, theme.Font, Math.Clamp(widget.Height / 4, 10, 28), primary);
+            text.MaxTextWidth = Math.Max(1, widget.Width - 12);
+            text.MaxTextHeight = Math.Max(1, widget.Height - 8);
+            text.Trimming = TextTrimming.CharacterEllipsis;
+
+            context.DrawText(text, new Point(widget.X + 6, widget.Y + ((widget.Height - Math.Min(text.Height, text.MaxTextHeight)) / 2)));
+        }
+    }
+
+    private static void DrawTheme(DrawingContext context, Theme theme)
+    {
+        Color background = MultiColorConverter.ConvertToMediaColor(theme.BackgroundColor);
+        Color primary = MultiColorConverter.ConvertToMediaColor(theme.PrimaryColor);
+        Color secondary = MultiColorConverter.ConvertToMediaColor(theme.SecondaryColor);
+
+        Rect card = new(120, 100, Width - 240, Height - 200);
+        double radius = Math.Clamp(theme.CornerRadius * 2, 0, card.Height / 2);
+
+        context.DrawRoundedRectangle(new SolidColorBrush(screenColor), null, card, radius, radius);
+        context.DrawRoundedRectangle(new SolidColorBrush(background), null, card, radius, radius);
+
+        FormattedText title = CreateText(theme.Name, theme.Font, 96, primary);
+        title.MaxTextWidth = card.Width - 120;
+        title.MaxLineCount = 1;
+        title.Trimming = TextTrimming.CharacterEllipsis;
+        context.DrawText(title, new Point(card.X + 60, card.Y + 60));
+
+        FormattedText subtitle = CreateText(theme.Font, theme.Font, 48, secondary);
+        subtitle.MaxTextWidth = card.Width - 120;
+        subtitle.MaxLineCount = 1;
+        subtitle.Trimming = TextTrimming.CharacterEllipsis;
+        context.DrawText(subtitle, new Point(card.X + 60, card.Y + 60 + title.Height + 10));
+
+        Color[] swatches = [primary, secondary, background];
+        for (int i = 0; i < swatches.Length; i++)
+        {
+            Point center = new(card.X + 110 + (i * 130), card.Bottom - 110);
+            context.DrawEllipse(new SolidColorBrush(swatches[i]), new Pen(new SolidColorBrush(Color.FromArgb(0x60, 0x80, 0x80, 0x80)), 3), center, 50, 50);
+        }
+    }
+
+    private static FormattedText CreateText(string text, string font, double size, Color color)
+    {
+        return new FormattedText(text, CultureInfo.CurrentUICulture, FlowDirection.LeftToRight, new Typeface(font), size, new SolidColorBrush(color), 1.0);
+    }
+}

src/DesktopMagic/Manager.cs

@@ -461,6 +461,27 @@ public sealed class Manager
         SaveSettings();
     }
 
+    /// <summary>
+    /// Deletes the layout, drops the screen bindings pointing to it and reloads the screens.
+    /// </summary>
+    public void RemoveLayout(Layout layout)
+    {
+        _ = Settings.Layouts.Remove(layout);
+
+        List<string> boundScreens = Settings.ScreenLayouts
+            .Where(kvp => kvp.Value == layout.Name)
+            .Select(kvp => kvp.Key)
+            .ToList();
+
+        foreach (string screenId in boundScreens)
+        {
+            _ = Settings.ScreenLayouts.Remove(screenId);
+        }
+
+        SaveSettings();
+        LoadLayout();
+    }
+
     /// <summary>
     /// Gets all plugin windows currently shown on the given screen.
     /// </summary>

src/DesktopMagic/Pages/MainPage.xaml

@@ -2,6 +2,7 @@
       xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
       xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
       xmlns:ui="http://schemas.lepo.co/wpfui/2022/xaml"
+      xmlns:busyIndicator="https://github.com/moh3ngolshani/BusyIndicator"
       xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
       xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
       xmlns:local="clr-namespace:DesktopMagic.Pages"
@@ -12,97 +13,119 @@
       ScrollViewer.CanContentScroll="False"
       Title="MainPage">
 
-    <Grid Margin="{StaticResource DefaultMargin}">
-        <Grid.RowDefinitions>
-            <RowDefinition Height="auto" />
-            <RowDefinition Height="*" />
-            <RowDefinition Height="auto" />
-        </Grid.RowDefinitions>
+    <busyIndicator:BusyMask IsBusy="{Binding IsSharing}" IndicatorType="ThreeDots" BusyContent="{DynamicResource uploadingToModIo}" BusyContentMargin="0,20,0,0" Foreground="{DynamicResource TextFillColorPrimaryBrush}" Background="{DynamicResource ControlStrokeColorDefaultBrush}">
+        <Grid Margin="{StaticResource DefaultMargin}">
+            <Grid.RowDefinitions>
+                <RowDefinition Height="auto" />
+                <RowDefinition Height="*" />
+                <RowDefinition Height="auto" />
+            </Grid.RowDefinitions>
 
-        <ui:Card Padding="5" Margin="0 0 0 5">
-            <Grid>
-                <Grid.ColumnDefinitions>
-                    <ColumnDefinition />
-                    <ColumnDefinition Width="10" />
-                    <ColumnDefinition />
-                </Grid.ColumnDefinitions>
-                <ui:ToggleSwitch x:Name="editCheckBox" Height="30" VerticalAlignment="Center" Margin="5 0 0 0" Content="{DynamicResource editLayout}" Click="EditCheckBox_Click" />
-                <ui:TextBox Grid.Column="2" Text="{Binding PluginsSearchText, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" TextChanged="AllPluginsSearchTextBox_TextChanged" PlaceholderText="{DynamicResource searchInstalledPlugins}" Icon="{ui:SymbolIcon Search24}" IconPlacement="Right" />
-            </Grid>
-        </ui:Card>
-
-        <ScrollViewer Background="#FFBBBBBB" PreviewMouseWheel="ScrollViewer_PreviewMouseWheel" Grid.Row="1" VerticalAlignment="Stretch" VerticalContentAlignment="Top">
-            <ItemsControl x:Name="pluginsItemsControl" ItemsSource="{Binding SelectedLayout.Plugins}">
-                <ItemsControl.ItemTemplate>
-                    <DataTemplate>
-                        <ui:CardExpander Tag="{Binding}" Margin="0 0 0 5" Expanded="OptionsCardExpander_Expanded">
-                            <ui:CardExpander.Header>
-                                <Grid>
-                                    <Grid.RowDefinitions>
-                                        <RowDefinition Height="Auto" />
-                                        <RowDefinition Height="Auto" />
-                                    </Grid.RowDefinitions>
-                                    <Grid.ColumnDefinitions>
-                                        <ColumnDefinition Width="*" />
-                                        <ColumnDefinition Width="Auto" />
-                                    </Grid.ColumnDefinitions>
-                                    <ui:TextBlock Grid.Row="0" Grid.Column="0" FontTypography="Body" Text="{Binding Value.Metadata.Name}" />
-                                    <Label Grid.Row="1" Grid.Column="0" Foreground="{ui:ThemeResource TextFillColorTertiaryBrush}" FontSize="12" ContentStringFormat="{DynamicResource authorFormat}">
-                                        <Label.Style>
-                                            <Style TargetType="Label" BasedOn="{StaticResource {x:Type Label}}">
-                                                <Setter Property="Content" Value="{Binding Value.Metadata.Author, Converter={StaticResource UnderscoreEscapingConverter}}" />
-                                                <Style.Triggers>
-                                                    <DataTrigger Binding="{Binding Value.Metadata.Author}" Value="{x:Null}">
-                                                        <Setter Property="Content" Value="{DynamicResource unknown}" />
-                                                    </DataTrigger>
-                                                </Style.Triggers>
-                                            </Style>
-                                        </Label.Style>
-                                    </Label>
-                                    <ui:ToggleSwitch Grid.Row="0" Grid.RowSpan="2" Grid.Column="1" Click="PluginCheckBox_Click" IsChecked="{Binding Value.Enabled}" Tag="{Binding Key}" Margin="0,0,16,0" VerticalAlignment="Center" />
-                                </Grid>
-                            </ui:CardExpander.Header>
-                        </ui:CardExpander>
-                    </DataTemplate>
-                </ItemsControl.ItemTemplate>
-            </ItemsControl>
-        </ScrollViewer>
-
-        <ui:Card Grid.Row="2" Grid.ColumnSpan="2" Margin="0 5 0 0" Padding="5">
-            <Grid>
-                <Grid.RowDefinitions>
-                    <RowDefinition Height="auto" />
-                    <RowDefinition Height="5" />
-                    <RowDefinition Height="auto" />
-                </Grid.RowDefinitions>
-                <Grid.ColumnDefinitions>
-                    <ColumnDefinition Width="auto" />
-                    <ColumnDefinition Width="5" />
-                    <ColumnDefinition Width="1*" />
-                </Grid.ColumnDefinitions>
-
-                <ui:Button x:Name="screenSelectorButton" VerticalAlignment="Stretch" Padding="10,4" Click="ScreenSelectorButton_Click">
-                    <StackPanel Orientation="Horizontal" VerticalAlignment="Center">
-                        <TextBlock x:Name="screenSelectorButtonText" VerticalAlignment="Center" Text="{Binding SelectedScreen.DisplayName}" />
-                        <ui:SymbolIcon Symbol="ChevronDown24" Margin="8,0,0,0" FontSize="12" />
-                    </StackPanel>
-                </ui:Button>
-
-                <ComboBox x:Name="layoutsComboBox" Grid.Column="2" ItemsSource="{Binding Settings.Layouts}" DisplayMemberPath="Name" SelectedValue="{Binding SelectedLayoutName}" SelectedValuePath="Name" VerticalAlignment="Center" SelectionChanged="LayoutsComboBox_SelectionChanged" />
-
-                <Grid Grid.Row="2" Grid.ColumnSpan="3">
+            <ui:Card Padding="5" Margin="0 0 0 5">
+                <Grid>
                     <Grid.ColumnDefinitions>
+                        <ColumnDefinition />
+                        <ColumnDefinition Width="10" />
+                        <ColumnDefinition />
+                    </Grid.ColumnDefinitions>
+                    <ui:ToggleSwitch x:Name="editCheckBox" Height="30" VerticalAlignment="Center" Margin="5 0 0 0" Content="{DynamicResource editLayout}" Click="EditCheckBox_Click" />
+                    <ui:TextBox Grid.Column="2" Text="{Binding PluginsSearchText, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" TextChanged="AllPluginsSearchTextBox_TextChanged" PlaceholderText="{DynamicResource searchInstalledPlugins}" Icon="{ui:SymbolIcon Search24}" IconPlacement="Right" />
+                </Grid>
+            </ui:Card>
+
+            <ScrollViewer Background="#FFBBBBBB" PreviewMouseWheel="ScrollViewer_PreviewMouseWheel" Grid.Row="1" VerticalAlignment="Stretch" VerticalContentAlignment="Top">
+                <ItemsControl x:Name="pluginsItemsControl" ItemsSource="{Binding SelectedLayout.Plugins}">
+                    <ItemsControl.ItemTemplate>
+                        <DataTemplate>
+                            <ui:CardExpander Tag="{Binding}" Margin="0 0 0 5" Expanded="OptionsCardExpander_Expanded">
+                                <ui:CardExpander.Header>
+                                    <Grid>
+                                        <Grid.RowDefinitions>
+                                            <RowDefinition Height="Auto" />
+                                            <RowDefinition Height="Auto" />
+                                        </Grid.RowDefinitions>
+                                        <Grid.ColumnDefinitions>
+                                            <ColumnDefinition Width="*" />
+                                            <ColumnDefinition Width="Auto" />
+                                        </Grid.ColumnDefinitions>
+                                        <ui:TextBlock Grid.Row="0" Grid.Column="0" FontTypography="Body" Text="{Binding Value.Metadata.Name}" />
+                                        <Label Grid.Row="1" Grid.Column="0" Foreground="{ui:ThemeResource TextFillColorTertiaryBrush}" FontSize="12" ContentStringFormat="{DynamicResource authorFormat}">
+                                            <Label.Style>
+                                                <Style TargetType="Label" BasedOn="{StaticResource {x:Type Label}}">
+                                                    <Setter Property="Content" Value="{Binding Value.Metadata.Author, Converter={StaticResource UnderscoreEscapingConverter}}" />
+                                                    <Style.Triggers>
+                                                        <DataTrigger Binding="{Binding Value.Metadata.Author}" Value="{x:Null}">
+                                                            <Setter Property="Content" Value="{DynamicResource unknown}" />
+                                                        </DataTrigger>
+                                                    </Style.Triggers>
+                                                </Style>
+                                            </Label.Style>
+                                        </Label>
+                                        <ui:ToggleSwitch Grid.Row="0" Grid.RowSpan="2" Grid.Column="1" Click="PluginCheckBox_Click" IsChecked="{Binding Value.Enabled}" Tag="{Binding Key}" Margin="0,0,16,0" VerticalAlignment="Center" />
+                                    </Grid>
+                                </ui:CardExpander.Header>
+                            </ui:CardExpander>
+                        </DataTemplate>
+                    </ItemsControl.ItemTemplate>
+                </ItemsControl>
+            </ScrollViewer>
+
+            <ui:Card Grid.Row="2" Grid.ColumnSpan="2" Margin="0 5 0 0" Padding="5">
+                <Grid>
+                    <Grid.RowDefinitions>
+                        <RowDefinition Height="auto" />
+                        <RowDefinition Height="5" />
+                        <RowDefinition Height="auto" />
+                    </Grid.RowDefinitions>
+                    <Grid.ColumnDefinitions>
+                        <ColumnDefinition Width="auto" />
+                        <ColumnDefinition Width="5" />
                         <ColumnDefinition Width="1*" />
-                        <ColumnDefinition Width="5" />
-                        <ColumnDefinition Width="0.5*" />
-                        <ColumnDefinition Width="5" />
-                        <ColumnDefinition Width="0.5*" />
                     </Grid.ColumnDefinitions>
 
-                    <ui:Button x:Name="newLayoutButton" Content="{DynamicResource newLayout}" Icon="{ui:SymbolIcon Add24}" Grid.Column="2" HorizontalAlignment="Stretch" Click="NewLayoutButton_Click" FontWeight="Regular" />
-                    <ui:Button x:Name="removeLayoutButton" Content="{DynamicResource deleteLayout}" Icon="{ui:SymbolIcon Delete24}" Grid.Column="4" HorizontalAlignment="Stretch" Click="RemoveLayoutButton_Click" FontWeight="Regular" />
+                    <ui:Button x:Name="screenSelectorButton" VerticalAlignment="Stretch" Padding="10,4" Click="ScreenSelectorButton_Click">
+                        <StackPanel Orientation="Horizontal" VerticalAlignment="Center">
+                            <TextBlock x:Name="screenSelectorButtonText" VerticalAlignment="Center" Text="{Binding SelectedScreen.DisplayName}" />
+                            <ui:SymbolIcon Symbol="ChevronDown24" Margin="8,0,0,0" FontSize="12" />
+                        </StackPanel>
+                    </ui:Button>
+
+                    <ComboBox x:Name="layoutsComboBox" Grid.Column="2" ItemsSource="{Binding Settings.Layouts}" DisplayMemberPath="Name" SelectedValue="{Binding SelectedLayoutName}" SelectedValuePath="Name" VerticalAlignment="Center" SelectionChanged="LayoutsComboBox_SelectionChanged" />
+
+                    <Grid Grid.Row="2" Grid.ColumnSpan="3">
+                        <Grid.ColumnDefinitions>
+                            <ColumnDefinition Width="1*" />
+                            <ColumnDefinition Width="5" />
+                            <ColumnDefinition Width="0.5*" />
+                            <ColumnDefinition Width="5" />
+                            <ColumnDefinition Width="0.5*" />
+                        </Grid.ColumnDefinitions>
+
+                        <ui:Button x:Name="shareLayoutButton" Icon="{ui:SymbolIcon Share24}" Grid.Column="0" HorizontalAlignment="Stretch" Click="ShareLayoutButton_Click" FontWeight="Regular">
+                            <TextBlock>
+                                <TextBlock.Style>
+                                    <Style TargetType="TextBlock">
+                                        <Setter Property="Text" Value="{DynamicResource shareOnModIo}" />
+                                        <Style.Triggers>
+                                            <DataTrigger Binding="{Binding SelectedLayout.ShareState}" Value="Modified">
+                                                <Setter Property="Text" Value="{DynamicResource updateOnModIo}" />
+                                            </DataTrigger>
+                                            <DataTrigger Binding="{Binding SelectedLayout.ShareState}" Value="UpToDate">
+                                                <Setter Property="Text" Value="{DynamicResource sharedOnModIo}" />
+                                            </DataTrigger>
+                                            <DataTrigger Binding="{Binding SelectedLayout.ShareState}" Value="NotOwner">
+                                                <Setter Property="Text" Value="{DynamicResource shareCopyOnModIo}" />
+                                            </DataTrigger>
+                                        </Style.Triggers>
+                                    </Style>
+                                </TextBlock.Style>
+                            </TextBlock>
+                        </ui:Button>
+                        <ui:Button x:Name="newLayoutButton" Content="{DynamicResource newLayout}" Icon="{ui:SymbolIcon Add24}" Grid.Column="2" HorizontalAlignment="Stretch" Click="NewLayoutButton_Click" FontWeight="Regular" />
+                        <ui:Button x:Name="removeLayoutButton" Content="{DynamicResource deleteLayout}" Icon="{ui:SymbolIcon Delete24}" Grid.Column="4" HorizontalAlignment="Stretch" Click="RemoveLayoutButton_Click" FontWeight="Regular" />
+                    </Grid>
                 </Grid>
-            </Grid>
-        </ui:Card>
-    </Grid>
+            </ui:Card>
+        </Grid>
+    </busyIndicator:BusyMask>
 </Page>

src/DesktopMagic/Pages/MainPage.xaml.cs

@@ -35,6 +35,7 @@ public partial class MainPage : Page
         // Subscribe to manager events
         _manager.PluginsChanged += OnPluginsChanged;
         _manager.EditModeChanged += OnEditModeChanged;
+        _manager.SettingsChanged += OnSettingsChanged;
 
         Loaded += MainPage_Loaded;
         Unloaded += MainPage_Unloaded;
@@ -46,6 +47,7 @@ public partial class MainPage : Page
         editCheckBox.IsChecked = _manager.IsEditMode;
 
         _dataContext.RefreshScreens();
+        RefreshShareState();
     }
 
     private void MainPage_Unloaded(object sender, RoutedEventArgs e)
@@ -53,6 +55,7 @@ public partial class MainPage : Page
         // Unsubscribe from events
         _manager.PluginsChanged -= OnPluginsChanged;
         _manager.EditModeChanged -= OnEditModeChanged;
+        _manager.SettingsChanged -= OnSettingsChanged;
     }
 
     private void OnPluginsChanged()
@@ -61,9 +64,20 @@ public partial class MainPage : Page
         {
             _dataContext.Settings = _manager.Settings;
             ApplyPluginsFilter();
+            RefreshShareState();
         });
     }
 
+    private void OnSettingsChanged()
+    {
+        Dispatcher.Invoke(RefreshShareState);
+    }
+
+    private void RefreshShareState()
+    {
+        ModIoService.RefreshShareState(_manager.SelectedLayout);
+    }
+
     private void OnEditModeChanged(bool editMode)
     {
         Dispatcher.Invoke(() =>
@@ -157,6 +171,21 @@ public partial class MainPage : Page
     private void LayoutsComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
     {
         ApplySelectedLayout();
+        RefreshShareState();
+    }
+
+    private async void ShareLayoutButton_Click(object sender, RoutedEventArgs e)
+    {
+        shareLayoutButton.IsEnabled = false;
+
+        try
+        {
+            await ModIoService.ShareAsync(_manager.SelectedLayout, Window.GetWindow(this), isBusy => _dataContext.IsSharing = isBusy);
+        }
+        finally
+        {
+            shareLayoutButton.IsEnabled = true;
+        }
     }
 
     /// <summary>
@@ -273,21 +302,10 @@ public partial class MainPage : Page
             return;
         }
 
-        _ = _manager.Settings.Layouts.Remove(layout);
+        // A subscribed layout would be downloaded again on the next sync.
+        await ModIoService.UnsubscribeAsync(layout);
 
-        // Remove any screen bindings pointing to the deleted layout
-        List<string> boundScreens = _manager.Settings.ScreenLayouts
-            .Where(kvp => kvp.Value == layout.Name)
-            .Select(kvp => kvp.Key)
-            .ToList();
-
-        foreach (string screenId in boundScreens)
-        {
-            _ = _manager.Settings.ScreenLayouts.Remove(screenId);
-        }
-
-        _manager.SaveSettings();
-        _manager.LoadLayout();
+        _manager.RemoveLayout(layout);
         _dataContext.RefreshSelection();
     }
 

src/DesktopMagic/Pages/ThemePage.xaml

@@ -2,6 +2,7 @@
       xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
       xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
       xmlns:ui="http://schemas.lepo.co/wpfui/2022/xaml"
+      xmlns:busyIndicator="https://github.com/moh3ngolshani/BusyIndicator"
       xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
       xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
       xmlns:local="clr-namespace:DesktopMagic.Pages"
@@ -9,44 +10,66 @@
       d:DesignHeight="450" d:DesignWidth="800"
       Title="ThemePage">
 
-    <Grid Margin="{StaticResource DefaultMargin}">
-        <Grid.RowDefinitions>
-            <RowDefinition Height="*" />
-            <RowDefinition Height="auto" />
-        </Grid.RowDefinitions>
+    <busyIndicator:BusyMask IsBusy="{Binding IsSharing}" IndicatorType="ThreeDots" BusyContent="{DynamicResource uploadingToModIo}" BusyContentMargin="0,20,0,0" Foreground="{DynamicResource TextFillColorPrimaryBrush}" Background="{DynamicResource ControlStrokeColorDefaultBrush}">
+        <Grid Margin="{StaticResource DefaultMargin}">
+            <Grid.RowDefinitions>
+                <RowDefinition Height="*" />
+                <RowDefinition Height="auto" />
+            </Grid.RowDefinitions>
         
-        <ui:ListView x:Name="themesListBox" Grid.Row="0" Grid.ColumnSpan="1" ItemsSource="{Binding Settings.Themes}" SelectedValue="{Binding SelectedLayout.CurrentThemeName}" SelectedValuePath="Name" SelectedIndex="2" SelectionMode="Single">
-            <ui:ListView.ItemTemplate>
-                <DataTemplate>
-                    <Grid>
-                        <Grid.ColumnDefinitions>
-                            <ColumnDefinition Width="*" />
-                            <ColumnDefinition Width="Auto" />
-                        </Grid.ColumnDefinitions>
-                        <TextBlock Margin="8" VerticalAlignment="Center" FontWeight="SemiBold" Text="{Binding Name, Mode=OneWay}" />
-                        <StackPanel Grid.Column="1" VerticalAlignment="Center" Orientation="Horizontal" Margin="{StaticResource DefaultMargin}">
-                            <ui:Button x:Name="editThemeButton" Content="{DynamicResource editTheme}" Icon="{ui:SymbolIcon Color24}" HorizontalAlignment="Stretch" Click="EditThemeButton_Click" FontWeight="Regular" Tag="{Binding}">
+            <ui:ListView x:Name="themesListBox" Grid.Row="0" Grid.ColumnSpan="1" ItemsSource="{Binding Settings.Themes}" SelectedValue="{Binding SelectedLayout.CurrentThemeName}" SelectedValuePath="Name" SelectedIndex="2" SelectionMode="Single">
+                <ui:ListView.ItemTemplate>
+                    <DataTemplate>
+                        <Grid>
+                            <Grid.ColumnDefinitions>
+                                <ColumnDefinition Width="*" />
+                                <ColumnDefinition Width="Auto" />
+                            </Grid.ColumnDefinitions>
+                            <TextBlock Margin="8" VerticalAlignment="Center" FontWeight="SemiBold" Text="{Binding Name, Mode=OneWay}" />
+                            <StackPanel Grid.Column="1" VerticalAlignment="Center" Orientation="Horizontal" Margin="{StaticResource DefaultMargin}">
+                                <ui:Button x:Name="shareThemeButton" Icon="{ui:SymbolIcon Share24}" Margin="0 0 5 0" Click="ShareThemeButton_Click" FontWeight="Regular" Tag="{Binding}">
+                                    <TextBlock>
+                                        <TextBlock.Style>
+                                            <Style TargetType="TextBlock">
+                                                <Setter Property="Text" Value="{DynamicResource shareOnModIo}" />
+                                                <Style.Triggers>
+                                                    <DataTrigger Binding="{Binding ShareState}" Value="Modified">
+                                                        <Setter Property="Text" Value="{DynamicResource updateOnModIo}" />
+                                                    </DataTrigger>
+                                                    <DataTrigger Binding="{Binding ShareState}" Value="UpToDate">
+                                                        <Setter Property="Text" Value="{DynamicResource sharedOnModIo}" />
+                                                    </DataTrigger>
+                                                    <DataTrigger Binding="{Binding ShareState}" Value="NotOwner">
+                                                        <Setter Property="Text" Value="{DynamicResource shareCopyOnModIo}" />
+                                                    </DataTrigger>
+                                                </Style.Triggers>
+                                            </Style>
+                                        </TextBlock.Style>
+                                    </TextBlock>
+                                </ui:Button>
+                                <ui:Button x:Name="editThemeButton" Content="{DynamicResource editTheme}" Icon="{ui:SymbolIcon Color24}" HorizontalAlignment="Stretch" Click="EditThemeButton_Click" FontWeight="Regular" Tag="{Binding}">
 
-                            </ui:Button>
-                        </StackPanel>
-                    </Grid>
-                </DataTemplate>
-            </ui:ListView.ItemTemplate>
-        </ui:ListView>
+                                </ui:Button>
+                            </StackPanel>
+                        </Grid>
+                    </DataTemplate>
+                </ui:ListView.ItemTemplate>
+            </ui:ListView>
         
-        <ui:Card Grid.Row="1" Grid.ColumnSpan="2" Margin="0 5 0 0" Padding="5">
-            <Grid  >
-                <Grid.ColumnDefinitions>
-                    <ColumnDefinition Width="1*" />
-                    <ColumnDefinition Width="5" />
-                    <ColumnDefinition Width="0.5*" />
-                    <ColumnDefinition Width="5" />
-                    <ColumnDefinition Width="0.5*" />
-                </Grid.ColumnDefinitions>
+            <ui:Card Grid.Row="1" Grid.ColumnSpan="2" Margin="0 5 0 0" Padding="5">
+                <Grid  >
+                    <Grid.ColumnDefinitions>
+                        <ColumnDefinition Width="1*" />
+                        <ColumnDefinition Width="5" />
+                        <ColumnDefinition Width="0.5*" />
+                        <ColumnDefinition Width="5" />
+                        <ColumnDefinition Width="0.5*" />
+                    </Grid.ColumnDefinitions>
 
-                <ui:Button x:Name="newThemeButton" Content="{DynamicResource newTheme}" Icon="{ui:SymbolIcon Add24}" Grid.Column="2" HorizontalAlignment="Stretch" Click="AddThemeButton_Click" FontWeight="Regular"/>
-                <ui:Button x:Name="deleteThemeButton" Content="{DynamicResource deleteTheme}" Icon="{ui:SymbolIcon Delete24}"  Grid.Column="4"  HorizontalAlignment="Stretch" Click="DeleteThemeButton_Click" FontWeight="Regular"/>
-            </Grid>
-        </ui:Card>
-    </Grid>
+                    <ui:Button x:Name="newThemeButton" Content="{DynamicResource newTheme}" Icon="{ui:SymbolIcon Add24}" Grid.Column="2" HorizontalAlignment="Stretch" Click="AddThemeButton_Click" FontWeight="Regular"/>
+                    <ui:Button x:Name="deleteThemeButton" Content="{DynamicResource deleteTheme}" Icon="{ui:SymbolIcon Delete24}"  Grid.Column="4"  HorizontalAlignment="Stretch" Click="DeleteThemeButton_Click" FontWeight="Regular"/>
+                </Grid>
+            </ui:Card>
+        </Grid>
+    </busyIndicator:BusyMask>
 </Page>

src/DesktopMagic/Pages/ThemePage.xaml.cs

@@ -1,5 +1,6 @@
 using DesktopMagic.DataContexts;
 using DesktopMagic.Dialogs;
+using DesktopMagic.Helpers;
 using DesktopMagic.Plugins;
 
 using System.Linq;
@@ -30,9 +31,15 @@ public partial class ThemePage : Page
         // Subscribe to manager events
         _manager.SettingsChanged += OnSettingsChanged;
 
+        Loaded += ThemePage_Loaded;
         Unloaded += ThemePage_Unloaded;
     }
 
+    private void ThemePage_Loaded(object sender, RoutedEventArgs e)
+    {
+        RefreshShareStates();
+    }
+
     private void ThemePage_Unloaded(object sender, RoutedEventArgs e)
     {
         // Unsubscribe from events
@@ -44,9 +51,37 @@ public partial class ThemePage : Page
         Dispatcher.Invoke(() =>
         {
             _dataContext.Settings = _manager.Settings;
+            RefreshShareStates();
         });
     }
 
+    private void RefreshShareStates()
+    {
+        foreach (Theme theme in _manager.Settings.Themes)
+        {
+            ModIoService.RefreshShareState(theme);
+        }
+    }
+
+    private async void ShareThemeButton_Click(object sender, RoutedEventArgs e)
+    {
+        if (sender is not System.Windows.Controls.Button button || button.Tag is not Theme theme)
+        {
+            return;
+        }
+
+        button.IsEnabled = false;
+
+        try
+        {
+            await ModIoService.ShareAsync(theme, Window.GetWindow(this), isBusy => _dataContext.IsSharing = isBusy);
+        }
+        finally
+        {
+            button.IsEnabled = true;
+        }
+    }
+
     private async void AddThemeButton_Click(object sender, RoutedEventArgs e)
     {
         InputDialog inputDialog = new((string)FindResource("enterThemeName"))
@@ -104,6 +139,9 @@ public partial class ThemePage : Page
 
         if (themesListBox.SelectedItem is Theme theme)
         {
+            // A subscribed theme would be downloaded again on the next sync.
+            await ModIoService.UnsubscribeAsync(theme);
+
             _ = _manager.Settings.Themes.Remove(theme);
             _manager.SaveSettings();
         }
@@ -122,5 +160,6 @@ public partial class ThemePage : Page
         };
 
         _ = themeDialog.ShowDialog();
+        ModIoService.RefreshShareState(theme);
     }
 }

src/DesktopMagic/Plugins/PluginManager.xaml

@@ -31,19 +31,26 @@
             <ui:Card Grid.ColumnSpan="3" Padding="5" Margin="0 0 0 5">
                 <Grid>
                     <Grid.ColumnDefinitions>
+                        <ColumnDefinition Width="auto" />
+                        <ColumnDefinition Width="10" />
                         <ColumnDefinition />
                         <ColumnDefinition Width="10" />
                         <ColumnDefinition />
                     </Grid.ColumnDefinitions>
 
-                    <ui:TextBox Grid.Column="0" Text="{Binding AllPluginsSearchText, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" TextChanged="AllPluginsSearchTextBox_TextChanged" PlaceholderText="{DynamicResource searchAllPlugins}" Icon="{ui:SymbolIcon Search24}" IconPlacement="Right" />
-                    <ui:TextBox Grid.Column="2" Text="{Binding InstalledPluginsSearchText, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" TextChanged="InstalledPluginsSearchTextBox_TextChanged" PlaceholderText="{DynamicResource searchInstalledPlugins}" Icon="{ui:SymbolIcon Search24}" IconPlacement="Right" />
+                    <ComboBox x:Name="categoryComboBox" Grid.Column="0" MinWidth="130" VerticalAlignment="Center" SelectedIndex="{Binding CategoryIndex, Mode=TwoWay}" SelectionChanged="CategoryComboBox_SelectionChanged">
+                        <ComboBoxItem Content="{DynamicResource plugins}" />
+                        <ComboBoxItem Content="{DynamicResource layouts}" />
+                        <ComboBoxItem Content="{DynamicResource themes}" />
+                    </ComboBox>
+                    <ui:TextBox Grid.Column="2" Text="{Binding AllPluginsSearchText, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" TextChanged="AllPluginsSearchTextBox_TextChanged" PlaceholderText="{DynamicResource searchModIo}" Icon="{ui:SymbolIcon Search24}" IconPlacement="Right" />
+                    <ui:TextBox Grid.Column="4" Text="{Binding InstalledPluginsSearchText, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" TextChanged="InstalledPluginsSearchTextBox_TextChanged" PlaceholderText="{DynamicResource searchInstalled}" Icon="{ui:SymbolIcon Search24}" IconPlacement="Right" />
                 </Grid>
             </ui:Card>
 
             <busyIndicator:BusyMask Grid.Row="2" IsBusy="{Binding IsSearching}" IndicatorType="ThreeDots" BusyContent="Searching..." BusyContentMargin="0,50,0,0" Foreground="{DynamicResource TextFillColorPrimaryBrush}" Background="{DynamicResource ControlStrokeColorDefaultBrush}">
                 <ScrollViewer VerticalScrollBarVisibility="Auto" VerticalAlignment="Stretch" Padding="0" VerticalContentAlignment="Top" Margin="0 0 2.5 0">
-                    <ItemsControl ItemsSource="{Binding AllPlugins}">
+                    <ItemsControl ItemsSource="{Binding ShownAll}">
                         <ItemsControl.ItemTemplate>
                             <DataTemplate>
                                 <local:ModEntry Margin="0 0 0 5" />
@@ -56,7 +63,7 @@
                                         <Setter Property="Template">
                                             <Setter.Value>
                                                 <ControlTemplate>
-                                                    <TextBlock Text="No plugins found!" FontSize="20" VerticalAlignment="Center" HorizontalAlignment="Center" />
+                                                    <TextBlock Text="{DynamicResource nothingFound}" FontSize="20" VerticalAlignment="Center" HorizontalAlignment="Center" />
                                                 </ControlTemplate>
                                             </Setter.Value>
                                         </Setter>
@@ -69,7 +76,7 @@
             </busyIndicator:BusyMask>
 
             <ScrollViewer VerticalScrollBarVisibility="Auto" Grid.Row="2" Grid.Column="2" VerticalAlignment="Stretch" Padding="0" VerticalContentAlignment="Top">
-                <ItemsControl  ItemsSource="{Binding InstalledPlugins}" Margin="2.5 0 0 0">
+                <ItemsControl  ItemsSource="{Binding ShownInstalled}" Margin="2.5 0 0 0">
                     <ItemsControl.ItemTemplate>
                         <DataTemplate>
                             <local:ModEntry Margin="0 0 0 5"/>
@@ -82,7 +89,7 @@
                                     <Setter Property="Template">
                                         <Setter.Value>
                                             <ControlTemplate>
-                                                <TextBlock Text="No plugins found!" FontSize="20" VerticalAlignment="Center" HorizontalAlignment="Center" />
+                                                <TextBlock Text="{DynamicResource nothingFound}" FontSize="20" VerticalAlignment="Center" HorizontalAlignment="Center" />
                                             </ControlTemplate>
                                         </Setter.Value>
                                     </Setter>

src/DesktopMagic/Plugins/PluginManager.xaml.cs

@@ -1,6 +1,7 @@
 using DesktopMagic.DataContexts;
 using DesktopMagic.Dialogs;
 using DesktopMagic.Helpers;
+using DesktopMagic.Settings;
 
 using Modio;
 using Modio.Filters;
@@ -32,8 +33,7 @@ namespace DesktopMagic.Plugins;
 /// </summary>
 public partial class PluginManager : Page
 {
-    private const int ModIoGameId = 5665;
-    private const string ModIoApiKey = "88e6ea774c3a502b06114e7fee0829ac";
+    private const uint ModIoGameId = ModIoService.GameId;
     private readonly HttpClient httpClient = new();
     private readonly PluginManagerDataContext pluginManagerDataContext = new();
     private readonly string pluginsPath = Path.Combine(App.ApplicationDataPath, "Plugins");
@@ -48,23 +48,16 @@ public partial class PluginManager : Page
     private bool changed = false;
     private Client modIoClient;
 
+    // mod.io data of the local layouts and themes linked to a mod, by mod ID.
+    private readonly Dictionary<uint, Mod> linkedMods = [];
+
     public PluginManager()
     {
         Resources.MergedDictionaries.Add(App.LanguageDictionary);
 
-        string? modIoAccessToken = MainWindowDataContext.GetSettings().ModIoAccessToken;
-
-        if (modIoAccessToken is null)
-        {
-            modIoClient = new Client(new Credentials(ModIoApiKey));
-            App.Logger.LogInfo("Initialized mod.io client without authentication", source: "PluginManager");
-        }
-        else
-        {
-            modIoClient = new Client(new Credentials(ModIoApiKey, modIoAccessToken));
-            pluginManagerDataContext.IsAuthenticated = true;
-            App.Logger.LogInfo("Initialized mod.io client with authentication", source: "PluginManager");
-        }
+        modIoClient = ModIoService.CreateClient();
+        pluginManagerDataContext.IsAuthenticated = ModIoService.IsAuthenticated;
+        App.Logger.LogInfo($"Initialized mod.io client {(ModIoService.IsAuthenticated ? "with" : "without")} authentication", source: "PluginManager");
 
         InitializeComponent();
 
@@ -72,7 +65,15 @@ public partial class PluginManager : Page
         searchTimer.Tick += async (sender, e) =>
         {
             searchTimer.Stop();
-            await SearchAllPlugins(pluginManagerDataContext.AllPluginsSearchText);
+
+            if (pluginManagerDataContext.Category == ModCategory.Plugins)
+            {
+                await SearchAllPlugins(pluginManagerDataContext.AllPluginsSearchText);
+            }
+            else
+            {
+                await SearchShared(pluginManagerDataContext.AllPluginsSearchText);
+            }
         };
 
         Loaded += PluginManager_Loaded;
@@ -222,7 +223,7 @@ public partial class PluginManager : Page
             IAsyncEnumerable<Mod> mods = modIoClient.Games[ModIoGameId].Mods.Search(filter).ToEnumerable();
             await foreach (Mod mod in mods)
             {
-                if (pluginIds.Contains(mod.Id))
+                if (pluginIds.Contains(mod.Id) || !ModIoService.IsPluginMod(mod))
                 {
                     continue;
                 }
@@ -237,6 +238,8 @@ public partial class PluginManager : Page
         }
 
         await SyncPlugins();
+        await UpdateLinkedItems();
+        await PopulateShared();
 
         pluginManagerDataContext.IsLoading = false;
         App.Logger.LogInfo("Plugin Manager initialization complete", source: "PluginManager");
@@ -353,20 +356,177 @@ public partial class PluginManager : Page
 
     private void InstalledPluginsSearchTextBox_TextChanged(object sender, System.Windows.Controls.TextChangedEventArgs e)
     {
-        if (string.IsNullOrWhiteSpace(pluginManagerDataContext.InstalledPluginsSearchText))
+        FilterInstalled();
+    }
+
+    private void FilterInstalled()
+    {
+        string searchText = pluginManagerDataContext.InstalledPluginsSearchText;
+
+        foreach (PluginEntryDataContext pluginEntryDataContext in pluginManagerDataContext.ShownInstalled)
         {
-            foreach (PluginEntryDataContext pluginEntryDataContext in pluginManagerDataContext.InstalledPlugins)
+            pluginEntryDataContext.IsVisible = string.IsNullOrWhiteSpace(searchText) || pluginEntryDataContext.Name.Contains(searchText, StringComparison.OrdinalIgnoreCase);
+        }
+    }
+
+    private async void CategoryComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
+    {
+        if (!IsLoaded)
+        {
+            return;
+        }
+
+        pluginManagerDataContext.CategoryIndex = categoryComboBox.SelectedIndex;
+        pluginManagerDataContext.IsLoading = true;
+        await PopulateShared();
+        FilterInstalled();
+        pluginManagerDataContext.IsLoading = false;
+    }
+
+    /// <summary>
+    /// Fetches the mods of all linked layouts and themes and applies newer versions.
+    /// Subscribed items are also updated by the subscription sync, this covers items installed while logged out.
+    /// </summary>
+    private async Task UpdateLinkedItems()
+    {
+        linkedMods.Clear();
+
+        foreach (IModIoShareable item in ModIoService.GetSharedItems().Where(item => item.ModIo is not null).ToList())
+        {
+            uint modId = item.ModIo!.ModId;
+
+            try
             {
-                pluginEntryDataContext.IsVisible = true;
+                Mod mod = await modIoClient.Games[ModIoGameId].Mods[modId].Get();
+                linkedMods[modId] = mod;
+
+                if (await ModIoService.UpdateAsync(item, mod, EnsurePluginInstalled))
+                {
+                    changed = true;
+                }
+            }
+            catch (Exception ex)
+            {
+                App.Logger.LogError($"Failed to check \"{item.Name}\" (mod {modId}) for updates: {ex.Message}", source: "PluginManager");
             }
         }
-        else
+    }
+
+    /// <summary>
+    /// Fills the lists of the selected layout or theme category.
+    /// </summary>
+    private async Task PopulateShared()
+    {
+        pluginManagerDataContext.InstalledShared.Clear();
+        pluginManagerDataContext.AllShared.Clear();
+
+        if (pluginManagerDataContext.Category == ModCategory.Plugins)
         {
-            foreach (PluginEntryDataContext pluginEntryDataContext in pluginManagerDataContext.InstalledPlugins)
+            return;
+        }
+
+        IEnumerable<IModIoShareable> items = pluginManagerDataContext.Category == ModCategory.Layouts
+            ? _manager.Settings.Layouts
+            : _manager.Settings.Themes;
+
+        foreach (IModIoShareable item in items.Where(item => item.ModIo is not null).ToList())
+        {
+            uint modId = item.ModIo!.ModId;
+
+            if (!linkedMods.TryGetValue(modId, out Mod? mod))
             {
-                pluginEntryDataContext.IsVisible = pluginEntryDataContext.Name.Contains(pluginManagerDataContext.InstalledPluginsSearchText, StringComparison.OrdinalIgnoreCase);
+                try
+                {
+                    mod = await modIoClient.Games[ModIoGameId].Mods[modId].Get();
+                    linkedMods[modId] = mod;
+                }
+                catch (Exception ex)
+                {
+                    App.Logger.LogError($"Failed to fetch mod {modId} of \"{item.Name}\": {ex.Message}", source: "PluginManager");
+                }
+            }
+
+            // Show the local name, it can differ from the mod name (e.g. "Default (2)").
+            PluginMetadata metadata = mod is null ? new PluginMetadata(item.Name, modId) : new PluginMetadata(mod) { Name = item.Name };
+            pluginManagerDataContext.InstalledShared.Add(new PluginEntryDataContext(metadata, new CommandHandler(async () => await RemoveShared(item)), PluginEntryDataContext.Mode.Uninstall));
+        }
+
+        await SearchShared(pluginManagerDataContext.AllPluginsSearchText);
+    }
+
+    private async Task SearchShared(string searchString)
+    {
+        pluginManagerDataContext.AllShared.Clear();
+
+        if (pluginManagerDataContext.Category == ModCategory.Plugins)
+        {
+            pluginManagerDataContext.IsSearching = false;
+            return;
+        }
+
+        string tag = pluginManagerDataContext.Category == ModCategory.Layouts ? SharePackage.LayoutTag : SharePackage.ThemeTag;
+        Filter filter = ModFilter.Tags.Eq(tag);
+
+        if (!string.IsNullOrWhiteSpace(searchString))
+        {
+            if (!searchString.Contains('*'))
+            {
+                searchString = $"*{searchString.Trim()}*";
+            }
+
+            filter = filter.And(ModFilter.Name.Like(searchString));
+        }
+
+        filter = filter.And(ModFilter.Popular.Desc()).Limit(100);
+
+        try
+        {
+            App.Logger.LogInfo($"Fetching shared {tag} mods from mod.io", source: "PluginManager");
+            IAsyncEnumerable<Mod> mods = modIoClient.Games[ModIoGameId].Mods.Search(filter).ToEnumerable();
+            await foreach (Mod mod in mods)
+            {
+                if (ModIoService.FindLinkedItem(mod.Id) is not null)
+                {
+                    continue;
+                }
+
+                pluginManagerDataContext.AllShared.Add(new PluginEntryDataContext(new(mod), new CommandHandler(async () => await InstallShared(mod)), PluginEntryDataContext.Mode.Install));
             }
         }
+        catch (Exception ex)
+        {
+            App.Logger.LogError($"Failed to fetch shared {tag} mods from mod.io: {ex.Message}", source: "PluginManager");
+        }
+
+        pluginManagerDataContext.IsSearching = false;
+    }
+
+    private async Task InstallShared(Mod mod)
+    {
+        pluginManagerDataContext.IsLoading = true;
+
+        if (await ModIoService.InstallAsync(mod, EnsurePluginInstalled))
+        {
+            linkedMods[mod.Id] = mod;
+            changed = true;
+        }
+
+        await PopulateShared();
+        FilterInstalled();
+        pluginManagerDataContext.IsLoading = false;
+    }
+
+    private async Task RemoveShared(IModIoShareable item)
+    {
+        if (!await ModIoService.RemoveAsync(item))
+        {
+            return;
+        }
+
+        pluginManagerDataContext.IsLoading = true;
+        await PopulateShared();
+        FilterInstalled();
+        pluginManagerDataContext.IsLoading = false;
     }
 
     private async Task SearchAllPlugins(string searchString)
@@ -386,7 +546,7 @@ public partial class PluginManager : Page
             IAsyncEnumerable<Mod> mods = modIoClient.Games[ModIoGameId].Mods.Search(filter).ToEnumerable();
             await foreach (Mod mod in mods)
             {
-                if (pluginManagerDataContext.InstalledPlugins.Any(p => p.Id == mod.Id))
+                if (pluginManagerDataContext.InstalledPlugins.Any(p => p.Id == mod.Id) || !ModIoService.IsPluginMod(mod))
                 {
                     continue;
                 }
@@ -674,52 +834,21 @@ public class {pluginSafeName}Plugin : Plugin
     {
         if (pluginManagerDataContext.IsAuthenticated)
         {
-            App.Logger.LogInfo("Logging out from mod.io", source: "PluginManager");
-            MainWindowDataContext.GetSettings().ModIoAccessToken = null;
+            ModIoService.LogOut();
+            modIoClient = ModIoService.CreateClient();
             pluginManagerDataContext.IsAuthenticated = false;
             return;
         }
 
-        App.Logger.LogInfo("Starting mod.io authentication", source: "PluginManager");
-
         try
         {
-            InputDialog inputDialog = new((string)FindResource("enterModIoEmail"), "Plugin Manager")
+            if (!await ModIoService.LogInAsync(Window.GetWindow(this), "Plugin Manager"))
             {
-                Owner = Window.GetWindow(this),
-            };
-
-            if (inputDialog.ShowDialog() != true)
-            {
-                App.Logger.LogInfo("Authentication cancelled by user", source: "PluginManager");
-                return;
-            }
-
-            App.Logger.LogInfo($"Requesting authentication code for email: {inputDialog.ResponseText}", source: "PluginManager");
-            await modIoClient.Auth.RequestCode(ModIoApiKey, inputDialog.ResponseText);
-
-            inputDialog = new((string)FindResource("enterModIoAccessToken"), "Plugin Manager")
-            {
-                Owner = Window.GetWindow(this),
-            };
-
-            if (inputDialog.ShowDialog() != true)
-            {
-                App.Logger.LogInfo("Authentication cancelled by user", source: "PluginManager");
                 return;
             }
 
             pluginManagerDataContext.IsLoading = true;
-
-            AccessToken accessToken = await modIoClient.Auth.SecurityCode(ModIoApiKey, inputDialog.ResponseText);
-
-            if (accessToken.Value is not null)
-            {
-                modIoClient = new Client(new Credentials(ModIoApiKey, accessToken.Value));
-                App.Logger.LogInfo("Successfully authenticated with mod.io", source: "PluginManager");
-            }
-
-            MainWindowDataContext.GetSettings().ModIoAccessToken = accessToken.Value;
+            modIoClient = ModIoService.CreateClient();
             pluginManagerDataContext.IsAuthenticated = true;
 
             App.Logger.LogInfo("Subscribing to installed plugins on mod.io", source: "PluginManager");
@@ -739,7 +868,9 @@ public class {pluginSafeName}Plugin : Plugin
                 }
             }
 
+            await ModIoService.SubscribeToLinkedItemsAsync();
             await SyncPlugins();
+            await PopulateShared();
         }
         catch (Exception ex)
         {
@@ -767,7 +898,8 @@ public class {pluginSafeName}Plugin : Plugin
 
         try
         {
-            IReadOnlyList<Mod> mods = await modIoClient.User.GetSubscriptions(ModFilter.GameId.Eq(ModIoGameId)).ToList();
+            IReadOnlyList<Mod> subscriptions = await modIoClient.User.GetSubscriptions(ModFilter.GameId.Eq(ModIoGameId)).ToList();
+            List<Mod> mods = subscriptions.Where(ModIoService.IsPluginMod).ToList();
             App.Logger.LogInfo($"Found {mods.Count} subscribed plugins on mod.io", source: "PluginManager");
 
             List<PluginEntryDataContext> pluginsToRemove = [];
@@ -800,6 +932,12 @@ public class {pluginSafeName}Plugin : Plugin
             }
 
             App.Logger.LogInfo("Plugin sync completed", source: "PluginManager");
+
+            // Shared layouts and themes are synced after the plugins, so the plugins they use are installed first.
+            if (await ModIoService.SyncSubscriptionsAsync(subscriptions, EnsurePluginInstalled))
+            {
+                changed = true;
+            }
         }
         catch (Exception ex)
         {
@@ -807,6 +945,19 @@ public class {pluginSafeName}Plugin : Plugin
         }
     }
 
+    private async Task EnsurePluginInstalled(uint pluginId)
+    {
+        if (pluginManagerDataContext.InstalledPlugins.Any(p => p.Id == pluginId))
+        {
+            return;
+        }
+
+        App.Logger.LogInfo($"Installing plugin {pluginId} required by a shared layout", source: "PluginManager");
+        Mod mod = await modIoClient.Games[ModIoGameId].Mods[pluginId].Get();
+        await Install(mod);
+        pluginManagerDataContext.IsLoading = true;
+    }
+
     private string GetCsprojPath(string pluginName)
     {
         string pluginSafeName = GetPluginSafeName(pluginName);

src/DesktopMagic/Plugins/SettingElement.cs

@@ -7,6 +7,7 @@ namespace DesktopMagic.Plugins;
 public class SettingElement
 {
     private string jsonValue = string.Empty;
+    private bool shareable;
 
     [JsonIgnore]
     public Setting? Input { get; set; }
@@ -16,6 +17,17 @@ public class SettingElement
 
     public string Id { get; set; }
 
+    /// <summary>
+    /// Whether the value may be included when sharing a layout on mod.io.
+    /// Free-text values (URLs, locations, file paths, ...) can contain personal data and are never shared.
+    /// Persisted so the decision stays stable while the plugin is not loaded.
+    /// </summary>
+    public bool Shareable
+    {
+        get => Input is null ? shareable : IsShareableInput(Input);
+        set => shareable = value;
+    }
+
     public string JsonValue
     {
         get => Input?.GetJsonValue() ?? jsonValue;
@@ -40,6 +52,11 @@ public class SettingElement
         OrderIndex = orderIndex;
     }
 
+    private static bool IsShareableInput(Setting input)
+    {
+        return input is CheckBox or ColorPicker or ComboBox or IntegerUpDown or Slider;
+    }
+
 #pragma warning disable CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider declaring as nullable.
 
     [JsonConstructor]

src/DesktopMagic/Plugins/Theme.cs

@@ -1,5 +1,6 @@
 using DesktopMagic.Api;
 using DesktopMagic.Helpers;
+using DesktopMagic.Settings;
 
 using System.ComponentModel;
 using System.Runtime.CompilerServices;
@@ -11,7 +12,7 @@ using Color = System.Drawing.Color;
 
 namespace DesktopMagic.Plugins;
 
-public class Theme(string name) : ITheme, INotifyPropertyChanged
+public class Theme(string name) : ITheme, INotifyPropertyChanged, IModIoShareable
 {
     public event PropertyChangedEventHandler? PropertyChanged;
 
@@ -21,6 +22,23 @@ public class Theme(string name) : ITheme, INotifyPropertyChanged
     private string font = "Segoe UI";
     private int cornerRadius;
     private int margin;
+    private ModIoShareState shareState;
+
+    public ModIoLink? ModIo { get; set; }
+
+    [JsonIgnore]
+    public ModIoShareState ShareState
+    {
+        get => shareState;
+        set
+        {
+            if (shareState != value)
+            {
+                shareState = value;
+                OnPropertyChanged();
+            }
+        }
+    }
 
     public string Name
     {

src/DesktopMagic/Resources/Strings/StringResources.de.xaml

@@ -70,6 +70,30 @@
     <system:String x:Key="releaseInfoPublishedFormat">Veröffentlicht: {0}</system:String>
     <system:String x:Key="releaseInfoBodyLabel">Release Notes:</system:String>
     <system:String x:Key="openReleasePage">Release-Seite öffnen</system:String>
+    <system:String x:Key="close">Schließen</system:String>
+    <system:String x:Key="overwrite">Überschreiben</system:String>
+    <system:String x:Key="keepMine">Meine behalten</system:String>
+    <system:String x:Key="shareOnModIo">Auf mod.io teilen</system:String>
+    <system:String x:Key="updateOnModIo">Auf mod.io aktualisieren</system:String>
+    <system:String x:Key="sharedOnModIo">Auf mod.io ansehen</system:String>
+    <system:String x:Key="shareCopyOnModIo">Als neu auf mod.io teilen</system:String>
+    <system:String x:Key="enterModIoSummary">Kurze Zusammenfassung für mod.io eingeben:</system:String>
+    <system:String x:Key="enterModIoChangelog">Was hat sich geändert? (optional)</system:String>
+    <system:String x:Key="modIoShareLayoutWarning">Jeder auf mod.io kann dieses Layout herunterladen. Es enthält die aktivierten Widgets, ihre Positionen, die verwendeten Themes und ihre Nicht-Text-Einstellungen. Text-Einstellungen (z. B. URLs, Orte oder Dateipfade) und gespeicherte Widget-Daten werden nicht geteilt.</system:String>
+    <system:String x:Key="modIoShareThemeWarning">Jeder auf mod.io kann dieses Theme herunterladen.</system:String>
+    <system:String x:Key="modIoLocalPluginsWarning">Diese Widgets sind lokale Plugins, die andere nicht installieren können: {0}</system:String>
+    <system:String x:Key="modIoShareSuccess">"{0}" wurde auf mod.io veröffentlicht.</system:String>
+    <system:String x:Key="modIoUpdateSuccess">Das Update von "{0}" wurde auf mod.io veröffentlicht.</system:String>
+    <system:String x:Key="modIoShareFailed">Teilen auf mod.io fehlgeschlagen: {0}</system:String>
+    <system:String x:Key="modIoSessionExpired">Ihre mod.io-Sitzung ist abgelaufen. Bitte melden Sie sich erneut an.</system:String>
+    <system:String x:Key="modIoUpdateConflict">"{0}" wurde auf mod.io aktualisiert, aber Sie haben es auch lokal geändert. Ihre Änderungen mit der neuen Version überschreiben?</system:String>
+    <system:String x:Key="cannotShareEmptyLayout">Das leere Layout kann nicht geteilt werden!</system:String>
+    <system:String x:Key="layouts">Layouts</system:String>
+    <system:String x:Key="searchModIo">mod.io durchsuchen...</system:String>
+    <system:String x:Key="searchInstalled">Installierte durchsuchen...</system:String>
+    <system:String x:Key="nothingFound">Nichts gefunden!</system:String>
+    <system:String x:Key="modIoInstallFailed">Installation von "{0}" fehlgeschlagen: {1}</system:String>
+    <system:String x:Key="uploadingToModIo">Wird auf mod.io hochgeladen...</system:String>
     <col:ArrayList x:Key="musicVisualizerOptionsComboboxItems">
         <system:String>Unten</system:String>
         <system:String>Mitte</system:String>

src/DesktopMagic/Resources/Strings/StringResources.en.xaml

@@ -72,6 +72,30 @@
     <system:String x:Key="releaseInfoPublishedFormat">Published: {0}</system:String>
     <system:String x:Key="releaseInfoBodyLabel">Release notes:</system:String>
     <system:String x:Key="openReleasePage">Open release page</system:String>
+    <system:String x:Key="close">Close</system:String>
+    <system:String x:Key="overwrite">Overwrite</system:String>
+    <system:String x:Key="keepMine">Keep mine</system:String>
+    <system:String x:Key="shareOnModIo">Share on mod.io</system:String>
+    <system:String x:Key="updateOnModIo">Update on mod.io</system:String>
+    <system:String x:Key="sharedOnModIo">View on mod.io</system:String>
+    <system:String x:Key="shareCopyOnModIo">Share as new on mod.io</system:String>
+    <system:String x:Key="enterModIoSummary">Enter a short summary shown on mod.io:</system:String>
+    <system:String x:Key="enterModIoChangelog">What changed? (optional)</system:String>
+    <system:String x:Key="modIoShareLayoutWarning">Everyone on mod.io will be able to download this layout. It includes the enabled widgets, their positions, the used themes and their non-text settings. Text settings (e.g. URLs, locations or file paths) and saved widget data are not shared.</system:String>
+    <system:String x:Key="modIoShareThemeWarning">Everyone on mod.io will be able to download this theme.</system:String>
+    <system:String x:Key="modIoLocalPluginsWarning">These widgets are local plugins that others cannot install: {0}</system:String>
+    <system:String x:Key="modIoShareSuccess">"{0}" was published on mod.io.</system:String>
+    <system:String x:Key="modIoUpdateSuccess">The update of "{0}" was published on mod.io.</system:String>
+    <system:String x:Key="modIoShareFailed">Sharing on mod.io failed: {0}</system:String>
+    <system:String x:Key="modIoSessionExpired">Your mod.io session has expired. Please log in again.</system:String>
+    <system:String x:Key="modIoUpdateConflict">"{0}" was updated on mod.io, but you also changed it locally. Overwrite your changes with the new version?</system:String>
+    <system:String x:Key="cannotShareEmptyLayout">The empty layout cannot be shared!</system:String>
+    <system:String x:Key="layouts">Layouts</system:String>
+    <system:String x:Key="searchModIo">Search mod.io...</system:String>
+    <system:String x:Key="searchInstalled">Search installed...</system:String>
+    <system:String x:Key="nothingFound">Nothing found!</system:String>
+    <system:String x:Key="modIoInstallFailed">Installing "{0}" failed: {1}</system:String>
+    <system:String x:Key="uploadingToModIo">Uploading to mod.io...</system:String>
     <col:ArrayList x:Key="musicVisualizerOptionsComboboxItems">
         <system:String>Bottom</system:String>
         <system:String>Middle</system:String>

src/DesktopMagic/Settings/Layout.cs

@@ -9,7 +9,7 @@ using System.Text.Json.Serialization;
 
 namespace DesktopMagic.Settings;
 
-public class Layout(string name) : INotifyPropertyChanged
+public class Layout(string name) : INotifyPropertyChanged, IModIoShareable
 {
     public event PropertyChangedEventHandler? PropertyChanged;
 
@@ -17,6 +17,23 @@ public class Layout(string name) : INotifyPropertyChanged
     private string? currentThemeName = null;
     private Dictionary<uint, PluginSettings> plugins = [];
     private double screenAspectRatio = 0;
+    private ModIoShareState shareState;
+
+    public ModIoLink? ModIo { get; set; }
+
+    [JsonIgnore]
+    public ModIoShareState ShareState
+    {
+        get => shareState;
+        set
+        {
+            if (shareState != value)
+            {
+                shareState = value;
+                OnPropertyChanged();
+            }
+        }
+    }
 
     [JsonIgnore]
     public Theme Theme

src/DesktopMagic/Settings/ModIoLink.cs

@@ -0,0 +1,48 @@
+using System;
+
+namespace DesktopMagic.Settings;
+
+/// <summary>
+/// Connects a local layout or theme to the mod.io mod it was published as or downloaded from.
+/// </summary>
+public class ModIoLink
+{
+    public uint ModId { get; set; }
+
+    /// <summary>
+    /// The modfile (version) the local copy is based on.
+    /// </summary>
+    public uint ModfileId { get; set; }
+
+    /// <summary>
+    /// Hash of the shareable content at the last publish or download, used to detect local changes.
+    /// </summary>
+    public string? PublishedHash { get; set; }
+
+    /// <summary>
+    /// Whether the logged in mod.io user submitted the mod and is therefore allowed to upload new versions.
+    /// </summary>
+    public bool IsOwner { get; set; }
+
+    public Uri? ProfileUri { get; set; }
+}
+
+public enum ModIoShareState
+{
+    NotShared,
+    UpToDate,
+    Modified,
+    NotOwner
+}
+
+/// <summary>
+/// A local item (layout or theme) that can be shared on mod.io.
+/// </summary>
+public interface IModIoShareable
+{
+    string Name { get; }
+
+    ModIoLink? ModIo { get; set; }
+
+    ModIoShareState ShareState { get; set; }
+}