misc: Refactor Discord integration to listen on TitleIDs.CurrentApplication changes instead of waiting to be directly told when to change states.

src/Ryujinx.Common/TitleIDs.cs

@@ -8,7 +8,20 @@ namespace Ryujinx.Common
 {
     public static class TitleIDs
     {
-        public static Optional<string> CurrentApplication { get; set; }
+        private static string _currentApplication;
+
+        public static Optional<string> CurrentApplication
+        {
+            get => _currentApplication;
+            set
+            {
+                _currentApplication = value.OrElse(null);
+                
+                CurrentApplicationChanged?.Invoke(_currentApplication);
+            }
+        }
+
+        public static event Action<Optional<string>> CurrentApplicationChanged;
         
         public static GraphicsBackend SelectGraphicsBackend(string titleId, GraphicsBackend currentBackend)
         {

src/Ryujinx.HLE/Loaders/Processes/Extensions/FileSystemExtensions.cs

@@ -105,7 +105,6 @@ namespace Ryujinx.HLE.Loaders.Processes.Extensions
 
             // Initialize GPU.
             GraphicsConfig.TitleId = programId.ToString("X16");
-            TitleIDs.CurrentApplication = GraphicsConfig.TitleId;
             device.Gpu.HostInitalized.Set();
 
             if (!MemoryBlock.SupportsFlags(MemoryAllocationFlags.ViewCompatible))

src/Ryujinx.HLE/Loaders/Processes/ProcessLoader.cs

@@ -61,6 +61,8 @@ namespace Ryujinx.HLE.Loaders.Processes
                 {
                     _latestPid = processResult.ProcessId;
 
+                    TitleIDs.CurrentApplication = processResult.ProgramIdText;
+
                     return true;
                 }
             }
@@ -88,6 +90,8 @@ namespace Ryujinx.HLE.Loaders.Processes
                 {
                     _latestPid = processResult.ProcessId;
 
+                    TitleIDs.CurrentApplication = processResult.ProgramIdText;
+
                     return true;
                 }
             }
@@ -115,6 +119,8 @@ namespace Ryujinx.HLE.Loaders.Processes
                     if (processResult.ProgramId > 0x01000000000007FF)
                     {
                         _latestPid = processResult.ProcessId;
+
+                        TitleIDs.CurrentApplication = processResult.ProgramIdText;
                     }
 
                     return true;
@@ -134,6 +140,8 @@ namespace Ryujinx.HLE.Loaders.Processes
                 {
                     _latestPid = processResult.ProcessId;
 
+                    TitleIDs.CurrentApplication = processResult.ProgramIdText;
+
                     return true;
                 }
             }

src/Ryujinx.HLE/Switch.cs

@@ -2,6 +2,7 @@ using LibHac.Common;
 using LibHac.Ns;
 using Ryujinx.Audio.Backends.CompatLayer;
 using Ryujinx.Audio.Integration;
+using Ryujinx.Common;
 using Ryujinx.Common.Configuration;
 using Ryujinx.Graphics.Gpu;
 using Ryujinx.HLE.FileSystem;
@@ -17,6 +18,8 @@ namespace Ryujinx.HLE
 {
     public class Switch : IDisposable
     {
+        public static Switch Shared { get; private set; }
+        
         public HLEConfiguration Configuration { get; }
         public IHardwareDeviceDriver AudioDeviceDriver { get; }
         public MemoryBlock Memory { get; }
@@ -77,6 +80,8 @@ namespace Ryujinx.HLE
             DirtyHacks                              = Configuration.Hacks;
             UpdateVSyncInterval();
 #pragma warning restore IDE0055
+
+            Shared = this;
         }
 
         public void ProcessFrame()
@@ -145,6 +150,9 @@ namespace Ryujinx.HLE
                 AudioDeviceDriver.Dispose();
                 FileSystem.Dispose();
                 Memory.Dispose();
+
+                TitleIDs.CurrentApplication = null;
+                Shared = null;
             }
         }
     }

src/Ryujinx.UI.Common/DiscordIntegrationModule.cs

@@ -2,6 +2,7 @@ using DiscordRPC;
 using Humanizer;
 using Humanizer.Localisation;
 using Ryujinx.Common;
+using Ryujinx.HLE;
 using Ryujinx.HLE.Loaders.Processes;
 using Ryujinx.UI.App.Common;
 using Ryujinx.UI.Common.Configuration;
@@ -44,6 +45,16 @@ namespace Ryujinx.UI.Common
             };
 
             ConfigurationState.Instance.EnableDiscordIntegration.Event += Update;
+            TitleIDs.CurrentApplicationChanged += titleId =>
+            {
+                if (titleId)
+                    SwitchToPlayingState(
+                        ApplicationLibrary.LoadAndSaveMetaData(titleId),
+                        Switch.Shared.Processes.ActiveApplication
+                        );
+                else 
+                    SwitchToMainState();
+            };
         }
 
         private static void Update(object sender, ReactiveEventArgs<bool> evnt)
@@ -69,7 +80,7 @@ namespace Ryujinx.UI.Common
             }
         }
 
-        public static void SwitchToPlayingState(ApplicationMetadata appMeta, ProcessResult procRes)
+        private static void SwitchToPlayingState(ApplicationMetadata appMeta, ProcessResult procRes)
         {
             _discordClient?.SetPresence(new RichPresence
             {
@@ -88,7 +99,7 @@ namespace Ryujinx.UI.Common
             });
         }
 
-        public static void SwitchToMainState() => _discordClient?.SetPresence(_discordPresenceMain);
+        private static void SwitchToMainState() => _discordClient?.SetPresence(_discordPresenceMain);
 
         private static string TruncateToByteLength(string input)
         {

src/Ryujinx/AppHost.cs

@@ -578,7 +578,6 @@ namespace Ryujinx.Ava
         public void Stop()
         {
             _isActive = false;
-            DiscordIntegrationModule.SwitchToMainState();
         }
 
         private void Exit()
@@ -862,13 +861,11 @@ namespace Ryujinx.Ava
 
                 return false;
             }
-
-            ApplicationMetadata appMeta = ApplicationLibrary.LoadAndSaveMetaData(Device.Processes.ActiveApplication.ProgramIdText,
+            
+            ApplicationLibrary.LoadAndSaveMetaData(Device.Processes.ActiveApplication.ProgramIdText,
                 appMetadata => appMetadata.UpdatePreGame()
             );
 
-            DiscordIntegrationModule.SwitchToPlayingState(appMeta, Device.Processes.ActiveApplication);
-
             return true;
         }