Merge pull request #2082 from VictoriousRaptor/quicklook

Add external preview (QuickLook) support

.github/actions/spelling/expect.txt

@@ -98,6 +98,7 @@ Português
 Português (Brasil)
 Italiano
 Slovenský
+quicklook
 Tiếng Việt
 Droplex
 Preinstalled

Flow.Launcher.Core/Plugin/PluginManager.cs

@@ -1,4 +1,4 @@
-using Flow.Launcher.Core.ExternalPlugins;
+using Flow.Launcher.Core.ExternalPlugins;
 using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
@@ -90,6 +90,48 @@ namespace Flow.Launcher.Core.Plugin
             }).ToArray());
         }
 
+        public static async Task OpenExternalPreviewAsync(string path, bool sendFailToast = true)
+        {
+            await Task.WhenAll(AllPlugins.Select(plugin => plugin.Plugin switch
+            {
+                IAsyncExternalPreview p => p.OpenPreviewAsync(path, sendFailToast),
+                _ => Task.CompletedTask,
+            }).ToArray());
+        }
+
+        public static async Task CloseExternalPreviewAsync()
+        {
+            await Task.WhenAll(AllPlugins.Select(plugin => plugin.Plugin switch
+            {
+                IAsyncExternalPreview p => p.ClosePreviewAsync(),
+                _ => Task.CompletedTask,
+            }).ToArray());
+        }
+
+        public static async Task SwitchExternalPreviewAsync(string path, bool sendFailToast = true)
+        {
+            await Task.WhenAll(AllPlugins.Select(plugin => plugin.Plugin switch
+            {
+                IAsyncExternalPreview p => p.SwitchPreviewAsync(path, sendFailToast),
+                _ => Task.CompletedTask,
+            }).ToArray());
+        }
+
+        public static bool UseExternalPreview()
+        {
+            return GetPluginsForInterface<IAsyncExternalPreview>().Any(x => !x.Metadata.Disabled);
+        }
+
+        public static bool AllowAlwaysPreview()
+        {
+            var plugin = GetPluginsForInterface<IAsyncExternalPreview>().FirstOrDefault(x => !x.Metadata.Disabled);
+
+            if (plugin is null)
+                return false;
+
+            return ((IAsyncExternalPreview)plugin.Plugin).AllowAlwaysPreview();
+        }
+
         static PluginManager()
         {
             // validate user directory

Flow.Launcher.Infrastructure/UserSettings/Settings.cs

@@ -185,7 +185,9 @@ namespace Flow.Launcher.Infrastructure.UserSettings
         /// when false Alphabet static service will always return empty results
         /// </summary>
         public bool ShouldUsePinyin { get; set; } = false;
+
         public bool AlwaysPreview { get; set; } = false;
+        
         public bool AlwaysStartEn { get; set; } = false;
 
         private SearchPrecisionScore _querySearchPrecision = SearchPrecisionScore.Regular;

Flow.Launcher.Plugin/Interfaces/IAsyncExternalPreview.cs

@@ -0,0 +1,40 @@
+using System.Threading.Tasks;
+
+namespace Flow.Launcher.Plugin
+{
+    /// <summary>
+    /// This interface is for plugins that wish to provide file preview (external preview) 
+    /// via a third party app instead of the default preview.
+    /// </summary>
+    public interface IAsyncExternalPreview : IFeatures
+    {
+        /// <summary>
+        /// Method for opening/showing the preview.
+        /// </summary>
+        /// <param name="path">The file path to open the preview for</param>
+        /// <param name="sendFailToast">Whether to send a toast message notification on failure for the user</param>
+        public Task OpenPreviewAsync(string path, bool sendFailToast = true);
+
+        /// <summary>
+        /// Method for closing/hiding the preview.
+        /// </summary>
+        public Task ClosePreviewAsync();
+
+        /// <summary>
+        /// Method for switching the preview to the next file result. 
+        /// This requires the external preview be already open/showing
+        /// </summary>
+        /// <param name="path">The file path to switch the preview for</param>
+        /// <param name="sendFailToast">Whether to send a toast message notification on failure for the user</param>
+        public Task SwitchPreviewAsync(string path, bool sendFailToast = true);
+
+        /// <summary>
+        /// Allows the preview plugin to override the AlwaysPreview setting. Typically useful if plugin's preview does not
+        /// fully work well with being shown together when the query window appears with results.
+        /// When AlwaysPreview setting is on and this is set to false, the preview will not be shown when query 
+        /// window appears with results, instead the internal preview will be shown.
+        /// </summary>
+        /// <returns></returns>
+        public bool AllowAlwaysPreview();
+    }
+}

Flow.Launcher.Plugin/Result.cs

@@ -270,12 +270,12 @@ namespace Flow.Launcher.Plugin
             /// <summary>
             /// Full image used for preview panel
             /// </summary>
-            public string PreviewImagePath { get; set; }
+            public string PreviewImagePath { get; set; } = null;
 
             /// <summary>
             /// Determines if the preview image should occupy the full width of the preview panel.
             /// </summary>
-            public bool IsMedia { get; set; }
+            public bool IsMedia { get; set; } = false;
 
             /// <summary>
             /// Result description text that is shown at the bottom of the preview panel.
@@ -283,12 +283,17 @@ namespace Flow.Launcher.Plugin
             /// <remarks>
             /// When a value is not set, the <see cref="SubTitle"/> will be used.
             /// </remarks>
-            public string Description { get; set; }
+            public string Description { get; set; } = null;
 
             /// <summary>
             /// Delegate to get the preview panel's image
             /// </summary>
-            public IconDelegate PreviewDelegate { get; set; }
+            public IconDelegate PreviewDelegate { get; set; } = null;
+
+            /// <summary>
+            /// File path of the result. For third-party programs providing external preview.
+            /// </summary>
+            public string FilePath { get; set; } = null;
 
             /// <summary>
             /// Default instance of <see cref="PreviewInfo"/>
@@ -299,6 +304,7 @@ namespace Flow.Launcher.Plugin
                 Description = null,
                 IsMedia = false,
                 PreviewDelegate = null,
+                FilePath = null,
             };
         }
     }

Flow.Launcher/MainWindow.xaml

@@ -427,7 +427,7 @@
                         VerticalAlignment="Stretch"
                         Background="Transparent"
                         ShowsPreview="True"
-                        Visibility="{Binding PreviewVisible, Converter={StaticResource BoolToVisibilityConverter}}">
+                        Visibility="{Binding InternalPreviewVisible, Converter={StaticResource BoolToVisibilityConverter}}">
                         <GridSplitter.Template>
                             <ControlTemplate TargetType="{x:Type GridSplitter}">
                                 <Border Style="{DynamicResource PreviewBorderStyle}" />
@@ -439,7 +439,7 @@
                         Grid.Column="2"
                         VerticalAlignment="Stretch"
                         Style="{DynamicResource PreviewArea}"
-                        Visibility="{Binding PreviewVisible, Converter={StaticResource BoolToVisibilityConverter}}">
+                        Visibility="{Binding InternalPreviewVisible, Converter={StaticResource BoolToVisibilityConverter}}">
                         <Border
                             MinHeight="380"
                             d:DataContext="{d:DesignInstance vm:ResultViewModel}"

Flow.Launcher/MainWindow.xaml.cs

@@ -630,7 +630,7 @@ namespace Flow.Launcher
                 if (_settings.UseAnimation)
                     await Task.Delay(100);
 
-                if (_settings.HideWhenDeactivated)
+                if (_settings.HideWhenDeactivated && !_viewModel.ExternalPreviewVisible)
                 {
                     _viewModel.Hide();
                 }

Flow.Launcher/ViewModel/MainViewModel.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Threading;
@@ -407,6 +407,10 @@ namespace Flow.Launcher.ViewModel
             }
         }
 
+        #endregion
+
+        #region BasicCommands
+
         [RelayCommand]
         private void OpenSetting()
         {
@@ -581,56 +585,6 @@ namespace Flow.Launcher.ViewModel
             Settings.MaxResultsToShow -= 1;
         }
 
-        [RelayCommand]
-        public void TogglePreview()
-        {
-            if (!PreviewVisible)
-            {
-                ShowPreview();
-            }
-            else
-            {
-                HidePreview();
-            }
-
-            ContextMenu.IsPreviewOn = PreviewVisible;
-            History.IsPreviewOn = PreviewVisible;
-            Results.IsPreviewOn = PreviewVisible;
-        }
-
-        private void ShowPreview()
-        {
-            ResultAreaColumn = 1;
-            PreviewVisible = true;
-            Results.SelectedItem?.LoadPreviewImage();
-        }
-
-        private void HidePreview()
-        {
-            ResultAreaColumn = 3;
-            PreviewVisible = false;
-        }
-
-        public void ResetPreview()
-        {
-            if (Settings.AlwaysPreview == true)
-            {
-                ShowPreview();
-            }
-            else
-            {
-                HidePreview();
-            }
-        }
-
-        private void UpdatePreview()
-        {
-            if (PreviewVisible)
-            {
-                Results.SelectedItem?.LoadPreviewImage();
-            }
-        }
-
         /// <summary>
         /// we need move cursor to end when we manually changed query
         /// but we don't want to move cursor to end when query is updated from TextBox
@@ -805,10 +759,186 @@ namespace Flow.Launcher.ViewModel
         public string Image => Constant.QueryTextBoxIconImagePath;
 
         public bool StartWithEnglishMode => Settings.AlwaysStartEn;
+        
+        #endregion
 
-        public bool PreviewVisible { get; set; } = false;
+        #region Preview
 
-        public int ResultAreaColumn { get; set; } = 1;
+        public bool InternalPreviewVisible
+        {
+            get
+            {
+                if (ResultAreaColumn == ResultAreaColumnPreviewShown)
+                    return true;
+
+                if (ResultAreaColumn == ResultAreaColumnPreviewHidden)
+                    return false;
+#if DEBUG
+                throw new NotImplementedException("ResultAreaColumn should match ResultAreaColumnPreviewShown/ResultAreaColumnPreviewHidden value");
+#else
+                Log.Error("MainViewModel", "ResultAreaColumnPreviewHidden/ResultAreaColumnPreviewShown int value not implemented", "InternalPreviewVisible");
+#endif
+                return false;
+            }
+        }
+
+        private static readonly int ResultAreaColumnPreviewShown = 1;
+
+        private static readonly int ResultAreaColumnPreviewHidden = 3;
+
+        public int ResultAreaColumn { get; set; } = ResultAreaColumnPreviewShown;
+
+        // This is not a reliable indicator of whether external preview is visible due to the
+        // ability of manually closing/exiting the external preview program which, does not inform flow that
+        // preview is no longer available.
+        public bool ExternalPreviewVisible { get; set; } = false;
+
+        private void ShowPreview()
+        {
+            var useExternalPreview = PluginManager.UseExternalPreview();
+
+            switch (useExternalPreview)
+            {
+                case true
+                    when CanExternalPreviewSelectedResult(out var path):
+                    // Internal preview may still be on when user switches to external
+                    if (InternalPreviewVisible)
+                        HideInternalPreview();
+                    OpenExternalPreview(path);
+                    break;
+
+                case true
+                    when !CanExternalPreviewSelectedResult(out var _):
+                    if (ExternalPreviewVisible)
+                        CloseExternalPreview();
+                    ShowInternalPreview();
+                    break;
+
+                case false:
+                    ShowInternalPreview();
+                    break;
+            }
+        }
+
+        private void HidePreview()
+        {            
+            if (PluginManager.UseExternalPreview())
+                CloseExternalPreview();
+
+            if (InternalPreviewVisible)
+                HideInternalPreview();
+        }
+
+        [RelayCommand]
+        private void TogglePreview()
+        {
+            if (InternalPreviewVisible || ExternalPreviewVisible)
+            {
+                HidePreview();
+            }
+            else
+            {
+                ShowPreview();
+            }
+        }
+
+        private void ToggleInternalPreview()
+        {
+            if (!InternalPreviewVisible)
+            {
+                ShowInternalPreview();
+            }
+            else
+            {
+                HideInternalPreview();
+            }
+        }
+
+        private void OpenExternalPreview(string path, bool sendFailToast = true)
+        {
+            _ = PluginManager.OpenExternalPreviewAsync(path, sendFailToast).ConfigureAwait(false);
+            ExternalPreviewVisible = true;
+        }
+
+        private void CloseExternalPreview()
+        {
+            _ = PluginManager.CloseExternalPreviewAsync().ConfigureAwait(false);
+            ExternalPreviewVisible = false;
+        }
+
+        private void SwitchExternalPreview(string path, bool sendFailToast = true)
+        {
+            _ = PluginManager.SwitchExternalPreviewAsync(path,sendFailToast).ConfigureAwait(false);
+        }
+
+        private void ShowInternalPreview()
+        {
+            ResultAreaColumn = ResultAreaColumnPreviewShown;
+            Results.SelectedItem?.LoadPreviewImage();
+        }
+
+        private void HideInternalPreview()
+        {
+            ResultAreaColumn = ResultAreaColumnPreviewHidden;
+        }
+
+        public void ResetPreview()
+        {
+            switch (Settings.AlwaysPreview)
+            {
+                case true
+                    when PluginManager.AllowAlwaysPreview() && CanExternalPreviewSelectedResult(out var path):
+                    OpenExternalPreview(path);
+                    break;
+
+                case true:
+                    ShowInternalPreview();
+                    break;
+
+                case false:
+                    HidePreview();
+                    break;
+            }
+        }
+        
+        private void UpdatePreview()
+        {
+            switch (PluginManager.UseExternalPreview())
+            {
+                case true
+                    when CanExternalPreviewSelectedResult(out var path):
+                    if (ExternalPreviewVisible)
+                    {
+                        SwitchExternalPreview(path, false);
+                    }
+                    else if (InternalPreviewVisible)
+                    {
+                        HideInternalPreview();
+                        OpenExternalPreview(path);
+                    }
+                    break;
+
+                case true
+                    when !CanExternalPreviewSelectedResult(out var _):
+                    if (ExternalPreviewVisible)
+                    {
+                        CloseExternalPreview();
+                        ShowInternalPreview();
+                    }
+                    break;
+
+                case false
+                    when InternalPreviewVisible:
+                    Results.SelectedItem?.LoadPreviewImage();
+                    break;
+            }
+        }
+
+        private bool CanExternalPreviewSelectedResult(out string path)
+        {
+            path = Results.SelectedItem?.Result?.Preview.FilePath;
+            return !string.IsNullOrEmpty(path);
+        }
 
         #endregion
 
@@ -1232,6 +1362,9 @@ namespace Flow.Launcher.ViewModel
             lastContextMenuResult = new Result();
             lastContextMenuResults = new List<Result>();
 
+            if (ExternalPreviewVisible)
+                CloseExternalPreview();
+
             if (!SelectedIsFromQueryResults())
             {
                 SelectedResults = Results;

Plugins/Flow.Launcher.Plugin.Explorer/Search/ResultManager.cs

@@ -102,6 +102,10 @@ namespace Flow.Launcher.Plugin.Explorer.Search
                 AutoCompleteText = GetAutoCompleteText(title, query, path, ResultType.Folder),
                 TitleHighlightData = StringMatcher.FuzzySearch(query.Search, title).MatchData,
                 CopyText = path,
+                Preview = new Result.PreviewInfo
+                {
+                    FilePath = path,
+                },
                 Action = c =>
                 {
                     if (c.SpecialKeyState.ToModifierKeys() == ModifierKeys.Alt)
@@ -192,6 +196,10 @@ namespace Flow.Launcher.Plugin.Explorer.Search
                 Score = 500,
                 ProgressBar = progressValue,
                 ProgressBarColor = progressBarColor,
+                Preview = new Result.PreviewInfo
+                {
+                    FilePath = path,
+                },
                 Action = _ =>
                 {
                     OpenFolder(path);
@@ -261,10 +269,7 @@ namespace Flow.Launcher.Plugin.Explorer.Search
 
         internal static Result CreateFileResult(string filePath, Query query, int score = 0, bool windowsIndexed = false)
         {
-            Result.PreviewInfo preview = IsMedia(Path.GetExtension(filePath))
-                ? new Result.PreviewInfo { IsMedia = true, PreviewImagePath = filePath, }
-                : Result.PreviewInfo.Default;
-
+            bool isMedia = IsMedia(Path.GetExtension(filePath));
             var title = Path.GetFileName(filePath);
 
 
@@ -275,7 +280,12 @@ namespace Flow.Launcher.Plugin.Explorer.Search
                 Title = title,
                 SubTitle = Path.GetDirectoryName(filePath),
                 IcoPath = filePath,
-                Preview = preview,
+                Preview = new Result.PreviewInfo
+                {
+                    IsMedia = isMedia,
+                    PreviewImagePath = isMedia ? filePath : null,
+                    FilePath = filePath,
+                },
                 AutoCompleteText = GetAutoCompleteText(title, query, filePath, ResultType.File),
                 TitleHighlightData = StringMatcher.FuzzySearch(query.Search, title).MatchData,
                 Score = score,