Improve code quality

Author: Jack251970

Flow.Launcher.Core/Plugin/PluginManager.cs

@@ -260,13 +260,16 @@ public static async Task InitializePluginsAsync()
             }
         }
 
-        public static ICollection<PluginPair> ValidPluginsForQuery(Query query)
+        public static ICollection<PluginPair> ValidPluginsForQuery(Query query, bool quickSwitch)
         {
             if (query is null)
                 return Array.Empty<PluginPair>();
 
             if (!NonGlobalPlugins.TryGetValue(query.ActionKeyword, out var plugin))
-                return GlobalPlugins;
+                return quickSwitch ? GlobalPlugins.Where(p => p.Plugin is IAsyncQuickSwitch).ToList() : GlobalPlugins;
+
+            if (quickSwitch && plugin.Plugin is not IAsyncQuickSwitch)
+                return Array.Empty<PluginPair>();
 
             return new List<PluginPair>
             {

Flow.Launcher/ViewModel/MainViewModel.cs

@@ -1302,13 +1302,7 @@ private async Task QueryResultsAsync(bool searchDelay, bool isReQuery = false, b
 
             _lastQuery = query;
 
-            var plugins = PluginManager.ValidPluginsForQuery(query);
-
-            if (quickSwitch)
-            {
-                // Select for IAsyncQuickSwitch
-                plugins = new Collection<PluginPair>(plugins.Where(p => p.Plugin is IAsyncQuickSwitch).ToList());
-            }
+            var plugins = PluginManager.ValidPluginsForQuery(query, quickSwitch);
 
             if (plugins.Count == 1)
             {