Use explicit priorities for all internal communication events.

Penumbra/Api/PenumbraApi.cs

@@ -22,6 +22,7 @@ using Penumbra.String;
 using Penumbra.String.Classes;
 using Penumbra.Services;
 using Penumbra.Collections.Manager;
+using Penumbra.Communication;
 using Penumbra.Interop.Services;
 using Penumbra.UI;
 
@@ -34,13 +35,13 @@ public class PenumbraApi : IDisposable, IPenumbraApi
 
     public event Action<string>? PreSettingsPanelDraw
     {
-        add => _communicator.PreSettingsPanelDraw.Subscribe(value!);
+        add => _communicator.PreSettingsPanelDraw.Subscribe(value!, Communication.PreSettingsPanelDraw.Priority.Default);
         remove => _communicator.PreSettingsPanelDraw.Unsubscribe(value!);
     }
 
     public event Action<string>? PostSettingsPanelDraw
     {
-        add => _communicator.PostSettingsPanelDraw.Subscribe(value!);
+        add => _communicator.PostSettingsPanelDraw.Subscribe(value!, Communication.PostSettingsPanelDraw.Priority.Default);
         remove => _communicator.PostSettingsPanelDraw.Unsubscribe(value!);
     }
 
@@ -68,7 +69,7 @@ public class PenumbraApi : IDisposable, IPenumbraApi
                 return;
 
             CheckInitialized();
-            _communicator.CreatingCharacterBase.Subscribe(new Action<nint, string, nint, nint, nint>(value));
+            _communicator.CreatingCharacterBase.Subscribe(new Action<nint, string, nint, nint, nint>(value), Communication.CreatingCharacterBase.Priority.Api);
         }
         remove
         {
@@ -88,7 +89,7 @@ public class PenumbraApi : IDisposable, IPenumbraApi
                 return;
 
             CheckInitialized();
-            _communicator.CreatedCharacterBase.Subscribe(new Action<nint, string, nint>(value));
+            _communicator.CreatedCharacterBase.Subscribe(new Action<nint, string, nint>(value), Communication.CreatedCharacterBase.Priority.Api);
         }
         remove
         {
@@ -147,8 +148,8 @@ public class PenumbraApi : IDisposable, IPenumbraApi
         _lumina             = _dalamud.GameData.GameData;
 
         _resourceLoader.ResourceLoaded += OnResourceLoaded;
-        _communicator.ModPathChanged.Subscribe(ModPathChangeSubscriber);
-        _communicator.ModSettingChanged.Subscribe(OnModSettingChange, -1000);
+        _communicator.ModPathChanged.Subscribe(ModPathChangeSubscriber, ModPathChanged.Priority.Api);
+        _communicator.ModSettingChanged.Subscribe(OnModSettingChange, Communication.ModSettingChanged.Priority.Api);
     }
 
     public unsafe void Dispose()
@@ -180,7 +181,7 @@ public class PenumbraApi : IDisposable, IPenumbraApi
 
     public event ChangedItemClick? ChangedItemClicked
     {
-        add => _communicator.ChangedItemClick.Subscribe(new Action<MouseButton, object?>(value!));
+        add => _communicator.ChangedItemClick.Subscribe(new Action<MouseButton, object?>(value!), Communication.ChangedItemClick.Priority.Default);
         remove => _communicator.ChangedItemClick.Unsubscribe(new Action<MouseButton, object?>(value!));
     }
 
@@ -203,7 +204,7 @@ public class PenumbraApi : IDisposable, IPenumbraApi
         add
         {
             CheckInitialized();
-            _communicator.ModDirectoryChanged.Subscribe(value!);
+            _communicator.ModDirectoryChanged.Subscribe(value!, Communication.ModDirectoryChanged.Priority.Api);
         }
         remove
         {
@@ -220,7 +221,7 @@ public class PenumbraApi : IDisposable, IPenumbraApi
         add
         {
             CheckInitialized();
-            _communicator.EnabledChanged.Subscribe(value!, int.MinValue);
+            _communicator.EnabledChanged.Subscribe(value!, EnabledChanged.Priority.Api);
         }
         remove
         {
@@ -237,7 +238,7 @@ public class PenumbraApi : IDisposable, IPenumbraApi
 
     public event ChangedItemHover? ChangedItemTooltip
     {
-        add => _communicator.ChangedItemHover.Subscribe(new Action<object?>(value!));
+        add => _communicator.ChangedItemHover.Subscribe(new Action<object?>(value!), Communication.ChangedItemHover.Priority.Default);
         remove => _communicator.ChangedItemHover.Unsubscribe(new Action<object?>(value!));
     }
 

Penumbra/Api/TempModManager.cs

@@ -5,8 +5,9 @@ using Penumbra.Mods;
 using System.Collections.Generic;
 using Penumbra.Services;
 using Penumbra.String.Classes;
-using Penumbra.Collections.Manager;
-
+using Penumbra.Collections.Manager;
+using Penumbra.Communication;
+
 namespace Penumbra.Api;
 
 public enum RedirectResult
@@ -27,7 +28,7 @@ public class TempModManager : IDisposable
     public TempModManager(CommunicatorService communicator)
     {
         _communicator                        =  communicator;
-        _communicator.CollectionChange.Subscribe(OnCollectionChange);
+        _communicator.CollectionChange.Subscribe(OnCollectionChange, CollectionChange.Priority.TempModManager);
     }
 
     public void Dispose()

Penumbra/Collections/Cache/CollectionCacheManager.cs

@@ -8,6 +8,7 @@ using OtterGui.Classes;
 using Penumbra.Api;
 using Penumbra.Api.Enums;
 using Penumbra.Collections.Manager;
+using Penumbra.Communication;
 using Penumbra.Meta;
 using Penumbra.Mods;
 using Penumbra.Mods.Manager;
@@ -44,15 +45,15 @@ public class CollectionCacheManager : IDisposable
 
         if (!_active.Individuals.IsLoaded)
             _active.Individuals.Loaded += CreateNecessaryCaches;
-        _communicator.CollectionChange.Subscribe(OnCollectionChange, -100);
-        _communicator.ModPathChanged.Subscribe(OnModChangeAddition, -100);
-        _communicator.ModPathChanged.Subscribe(OnModChangeRemoval,  100);
-        _communicator.TemporaryGlobalModChange.Subscribe(OnGlobalModChange);
-        _communicator.ModOptionChanged.Subscribe(OnModOptionChange, -100);
-        _communicator.ModSettingChanged.Subscribe(OnModSettingChange);
-        _communicator.CollectionInheritanceChanged.Subscribe(OnCollectionInheritanceChange);
-        _communicator.ModDiscoveryStarted.Subscribe(OnModDiscoveryStarted);
-        _communicator.ModDiscoveryFinished.Subscribe(OnModDiscoveryFinished, -100);
+        _communicator.CollectionChange.Subscribe(OnCollectionChange, CollectionChange.Priority.CollectionCacheManager);
+        _communicator.ModPathChanged.Subscribe(OnModChangeAddition, ModPathChanged.Priority.CollectionCacheManagerAddition);
+        _communicator.ModPathChanged.Subscribe(OnModChangeRemoval,  ModPathChanged.Priority.CollectionCacheManagerRemoval);
+        _communicator.TemporaryGlobalModChange.Subscribe(OnGlobalModChange, TemporaryGlobalModChange.Priority.CollectionCacheManager);
+        _communicator.ModOptionChanged.Subscribe(OnModOptionChange, ModOptionChanged.Priority.CollectionCacheManager);
+        _communicator.ModSettingChanged.Subscribe(OnModSettingChange, ModSettingChanged.Priority.CollectionCacheManager);
+        _communicator.CollectionInheritanceChanged.Subscribe(OnCollectionInheritanceChange, CollectionInheritanceChanged.Priority.CollectionCacheManager);
+        _communicator.ModDiscoveryStarted.Subscribe(OnModDiscoveryStarted, ModDiscoveryStarted.Priority.CollectionCacheManager);
+        _communicator.ModDiscoveryFinished.Subscribe(OnModDiscoveryFinished, ModDiscoveryFinished.Priority.CollectionCacheManager);
 
         if (!MetaFileManager.CharacterUtility.Ready)
             MetaFileManager.CharacterUtility.LoadingFinished += IncrementCounters;

Penumbra/Collections/Manager/ActiveCollections.cs

@@ -6,6 +6,7 @@ using Dalamud.Interface.Internal.Notifications;
 using Newtonsoft.Json;
 using Newtonsoft.Json.Linq;
 using OtterGui;
+using Penumbra.Communication;
 using Penumbra.GameData.Actors;
 using Penumbra.GameData.Enums;
 using Penumbra.Services;
@@ -44,7 +45,7 @@ public class ActiveCollections : ISavable, IDisposable
         Default       = storage.DefaultNamed;
         Interface     = storage.DefaultNamed;
         Individuals   = new IndividualCollections(actors, config, false);
-        _communicator.CollectionChange.Subscribe(OnCollectionChange, -100);
+        _communicator.CollectionChange.Subscribe(OnCollectionChange, CollectionChange.Priority.ActiveCollections);
         LoadCollections();
         UpdateCurrentCollectionInUse();
         Individuals.Loaded += UpdateCurrentCollectionInUse;

Penumbra/Collections/Manager/CollectionStorage.cs

@@ -7,6 +7,7 @@ using System.Linq;
 using Dalamud.Interface.Internal.Notifications;
 using OtterGui;
 using OtterGui.Filesystem;
+using Penumbra.Communication;
 using Penumbra.Mods;
 using Penumbra.Mods.Manager;
 using Penumbra.Services;
@@ -56,10 +57,10 @@ public class CollectionStorage : IReadOnlyList<ModCollection>, IDisposable
         _communicator = communicator;
         _saveService  = saveService;
         _modStorage   = modStorage;
-        _communicator.ModDiscoveryStarted.Subscribe(OnModDiscoveryStarted);
-        _communicator.ModDiscoveryFinished.Subscribe(OnModDiscoveryFinished);
-        _communicator.ModPathChanged.Subscribe(OnModPathChange, 10);
-        _communicator.ModOptionChanged.Subscribe(OnModOptionChange, 100);
+        _communicator.ModDiscoveryStarted.Subscribe(OnModDiscoveryStarted, ModDiscoveryStarted.Priority.CollectionStorage);
+        _communicator.ModDiscoveryFinished.Subscribe(OnModDiscoveryFinished, ModDiscoveryFinished.Priority.CollectionStorage);
+        _communicator.ModPathChanged.Subscribe(OnModPathChange, ModPathChanged.Priority.CollectionStorage);
+        _communicator.ModOptionChanged.Subscribe(OnModOptionChange, ModOptionChanged.Priority.CollectionStorage);
         ReadCollections(out DefaultNamed);
     }
 

Penumbra/Collections/Manager/InheritanceManager.cs

@@ -4,6 +4,7 @@ using System.Linq;
 using Dalamud.Interface.Internal.Notifications;
 using OtterGui;
 using OtterGui.Filesystem;
+using Penumbra.Communication;
 using Penumbra.Mods.Manager;
 using Penumbra.Services;
 using Penumbra.Util;
@@ -47,7 +48,7 @@ public class InheritanceManager : IDisposable
         _modStorage   = modStorage;
 
         ApplyInheritances();
-        _communicator.CollectionChange.Subscribe(OnCollectionChange);
+        _communicator.CollectionChange.Subscribe(OnCollectionChange, CollectionChange.Priority.InheritanceManager);
     }
 
     public void Dispose()

Penumbra/Collections/Manager/TempCollectionManager.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using Penumbra.Api;
+using Penumbra.Communication;
 using Penumbra.GameData.Actors;
 using Penumbra.Mods;
 using Penumbra.Services;
@@ -27,7 +28,7 @@ public class TempCollectionManager : IDisposable
         _storage      = storage;
         Collections   = new IndividualCollections(actors, config, true);
 
-        _communicator.TemporaryGlobalModChange.Subscribe(OnGlobalModChange);
+        _communicator.TemporaryGlobalModChange.Subscribe(OnGlobalModChange, TemporaryGlobalModChange.Priority.TempCollectionManager);
     }
 
     public void Dispose()

Penumbra/Communication/ChangedItemClick.cs

@@ -0,0 +1,28 @@
+using System;
+using Penumbra.Api.Enums;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary>
+/// Triggered when a Changed Item in Penumbra is clicked.
+/// <list type="number">
+///     <item>Parameter is the clicked mouse button. </item>
+///     <item>Parameter is the clicked object data if any.. </item>
+/// </list>
+/// </summary>
+public sealed class ChangedItemClick : EventWrapper<Action<MouseButton, object?>, ChangedItemClick.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="Api.PenumbraApi.ChangedItemClicked"/>
+        Default = 0,
+    }
+
+    public ChangedItemClick()
+        : base(nameof(ChangedItemClick))
+    { }
+
+    public void Invoke(MouseButton button, object? data)
+        => Invoke(this, button, data);
+}

Penumbra/Communication/ChangedItemHover.cs

@@ -0,0 +1,29 @@
+using System;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary>
+/// Triggered when a Changed Item in Penumbra is hovered.
+/// <list type="number">
+///     <item>Parameter is the hovered object data if any. </item>
+/// </list>
+/// </summary>
+public sealed class ChangedItemHover : EventWrapper<Action<object?>, ChangedItemHover.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="Api.PenumbraApi.ChangedItemTooltip"/>
+        Default = 0,
+    }
+
+    public ChangedItemHover()
+        : base(nameof(ChangedItemHover))
+    { }
+
+    public void Invoke(object? data)
+        => Invoke(this, data);
+
+    public bool HasTooltip
+        => HasSubscribers;
+}

Penumbra/Communication/CollectionChange.cs

@@ -0,0 +1,54 @@
+using System;
+using Penumbra.Collections;
+using Penumbra.Collections.Manager;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary>
+/// Triggered whenever collection setup is changed.
+/// <list type="number">
+///     <item>Parameter is the type of the changed collection. (Inactive or Temporary for additions or deletions)</item>
+///     <item>Parameter is the old collection, or null on additions.</item>
+///     <item>Parameter is the new collection, or null on deletions.</item>
+///     <item>Parameter is the display name for Individual collections or an empty string otherwise.</item>
+/// </list> </summary>
+public sealed class CollectionChange : EventWrapper<Action<CollectionType, ModCollection?, ModCollection?, string>, CollectionChange.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="Collections.Cache.CollectionCacheManager.OnCollectionChange"/>
+        CollectionCacheManager = -2,
+
+        /// <seealso cref="Collections.Manager.ActiveCollections.OnCollectionChange"/>
+        ActiveCollections = -1,
+
+        /// <seealso cref="Api.TempModManager.OnCollectionChange"/>
+        TempModManager = 0,
+
+        /// <seealso cref="Collections.Manager.InheritanceManager.OnCollectionChange" />
+        InheritanceManager = 0,
+
+        /// <seealso cref="Interop.PathResolving.IdentifiedCollectionCache.CollectionChangeClear" />
+        IdentifiedCollectionCache = 0,
+
+        /// <seealso cref="UI.AdvancedWindow.ItemSwapTab.OnCollectionChange" />
+        ItemSwapTab = 0,
+
+        /// <seealso cref="UI.CollectionTab.CollectionSelector.OnCollectionChange" />
+        CollectionSelector = 0,
+
+        /// <seealso cref="UI.CollectionTab.IndividualAssignmentUi.UpdateIdentifiers"/>
+        IndividualAssignmentUi = 0,
+
+        /// <seealso cref="UI.ModsTab.ModFileSystemSelector.OnCollectionChange"/>
+        ModFileSystemSelector = 0,
+    }
+
+    public CollectionChange()
+        : base(nameof(CollectionChange))
+    { }
+
+    public void Invoke(CollectionType collectionType, ModCollection? oldCollection, ModCollection? newCollection, string displayName)
+        => Invoke(this, collectionType, oldCollection, newCollection, displayName);
+}

Penumbra/Communication/CollectionInheritanceChanged.cs

@@ -0,0 +1,34 @@
+using System;
+using Penumbra.Collections;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary>
+/// Triggered whenever a collections inheritances change.
+/// <list type="number">
+///     <item>Parameter is the collection whose ancestors were changed. </item>
+///     <item>Parameter is whether the change was itself inherited, i.e. if it happened in a direct parent (false) or a more removed ancestor (true). </item>
+/// </list>
+/// </summary>
+public sealed class CollectionInheritanceChanged : EventWrapper<Action<ModCollection, bool>, CollectionInheritanceChanged.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="Collections.Cache.CollectionCacheManager.OnCollectionInheritanceChange"/>
+        CollectionCacheManager = 0,
+
+        /// <seealso cref="UI.AdvancedWindow.ItemSwapTab.OnInheritanceChange"/>
+        ItemSwapTab = 0,
+
+        /// <seealso cref="UI.ModsTab.ModFileSystemSelector.OnInheritanceChange"/>
+        ModFileSystemSelector = 0,
+    }
+
+    public CollectionInheritanceChanged()
+        : base(nameof(CollectionInheritanceChanged))
+    { }
+
+    public void Invoke(ModCollection collection, bool inherited)
+        => Invoke(this, collection, inherited);
+}

Penumbra/Communication/CreatedCharacterBase.cs

@@ -0,0 +1,25 @@
+using System;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary> <list type="number">
+///     <item>Parameter is the game object for which a draw object is created. </item>
+///     <item>Parameter is the name of the applied collection. </item>
+///     <item>Parameter is the created draw object. </item>
+/// </list> </summary>
+public sealed class CreatedCharacterBase : EventWrapper<Action<nint, string, nint>, CreatedCharacterBase.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="Api.PenumbraApi.CreatedCharacterBase"/>
+        Api = 0,
+    }
+
+    public CreatedCharacterBase()
+        : base(nameof(CreatedCharacterBase))
+    { }
+
+    public void Invoke(nint gameObject, string appliedCollectionName, nint drawObject)
+        => Invoke(this, gameObject, appliedCollectionName, drawObject);
+}

Penumbra/Communication/CreatingCharacterBase.cs

@@ -0,0 +1,29 @@
+using System;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary>
+/// Triggered whenever a character base draw object is being created by the game.
+/// <list type="number">
+///     <item>Parameter is the game object for which a draw object is created. </item>
+///     <item>Parameter is the name of the applied collection. </item>
+///     <item>Parameter is a pointer to the model id (an uint). </item>
+///     <item>Parameter is a pointer to the customize array. </item>
+///     <item>Parameter is a pointer to the equip data array. </item>
+/// </list> </summary>
+public sealed class CreatingCharacterBase : EventWrapper<Action<nint, string, nint, nint, nint>, CreatingCharacterBase.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="Api.PenumbraApi.CreatingCharacterBase"/>
+        Api = 0,
+    }
+
+    public CreatingCharacterBase()
+        : base(nameof(CreatingCharacterBase))
+    { }
+
+    public void Invoke(nint gameObject, string appliedCollectionName, nint modelIdAddress, nint customizeArrayAddress, nint equipDataAddress)
+        => Invoke(this, gameObject, appliedCollectionName, modelIdAddress, customizeArrayAddress, equipDataAddress);
+}

Penumbra/Communication/EnabledChanged.cs

@@ -0,0 +1,26 @@
+using System;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary>
+/// Triggered when the general Enabled state of Penumbra is changed.
+/// <list type="number">
+///     <item>Parameter is whether Penumbra is now Enabled (true) or Disabled (false). </item>
+/// </list>
+/// </summary>
+public sealed class EnabledChanged : EventWrapper<Action<bool>, EnabledChanged.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="Api.PenumbraApi.EnabledChange"/>
+        Api = int.MinValue,
+    }
+
+    public EnabledChanged()
+        : base(nameof(EnabledChanged))
+    { }
+
+    public void Invoke(bool enabled)
+        => Invoke(this, enabled);
+}

Penumbra/Communication/ModDataChanged.cs

@@ -0,0 +1,35 @@
+using System;
+using Penumbra.Mods;
+using Penumbra.Mods.Manager;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary>
+/// Triggered whenever mod meta data or local data is changed.
+/// <list type="number">
+///     <item>Parameter is the type of data change for the mod, which can be multiple flags. </item>
+///     <item>Parameter is the changed mod. </item>
+///     <item>Parameter is the old name of the mod in case of a name change, and null otherwise. </item>
+/// </list> </summary>
+public sealed class ModDataChanged : EventWrapper<Action<ModDataChangeType, Mod, string?>, ModDataChanged.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="UI.ModsTab.ModFileSystemSelector.OnModDataChange"/>
+        ModFileSystemSelector = -10,
+
+        /// <seealso cref="Mods.Manager.ModCacheManager.OnModDataChange"/>
+        ModCacheManager = 0,
+
+        /// <seealso cref="Mods.ModFileSystem.OnDataChange"/>
+        ModFileSystem = 0,
+    }
+
+    public ModDataChanged()
+        : base(nameof(ModDataChanged))
+    { }
+
+    public void Invoke(ModDataChangeType changeType, Mod mod, string? oldName)
+        => Invoke(this, changeType, mod, oldName);
+}

Penumbra/Communication/ModDirectoryChanged.cs

@@ -0,0 +1,30 @@
+using System;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary>
+/// Triggered whenever the mod root directory changes.
+/// <list type="number">
+///     <item>Parameter is the full path of the new directory. </item>
+///     <item>Parameter is whether the new directory is valid. </item>
+/// </list>
+/// </summary>
+public sealed class ModDirectoryChanged : EventWrapper<Action<string, bool>, ModDirectoryChanged.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="Api.PenumbraApi.ModDirectoryChanged"/>
+        Api = 0,
+
+        /// <seealso cref="UI.FileDialogService.OnModDirectoryChange"/>
+        FileDialogService = 0,
+    }
+
+    public ModDirectoryChanged()
+        : base(nameof(ModDirectoryChanged))
+    { }
+
+    public void Invoke(string newModDirectory, bool newDirectoryValid)
+        => Invoke(this, newModDirectory, newDirectoryValid);
+}

Penumbra/Communication/ModDiscoveryFinished.cs

@@ -0,0 +1,33 @@
+using System;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary> Triggered whenever a new mod discovery has finished. </summary>
+public sealed class ModDiscoveryFinished : EventWrapper<Action, ModDiscoveryFinished.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="UI.ModsTab.ModFileSystemSelector.RestoreLastSelection"/>
+        ModFileSystemSelector = -200,
+
+        /// <seealso cref="Collections.Cache.CollectionCacheManager.OnModDiscoveryFinished"/>
+        CollectionCacheManager = -100,
+
+        /// <seealso cref="Collections.Manager.CollectionStorage.OnModDiscoveryFinished"/>
+        CollectionStorage = 0,
+
+        /// <seealso cref="Mods.Manager.ModCacheManager.OnModDiscoveryFinished"/>
+        ModCacheManager = 0,
+
+        /// <seealso cref="Mods.ModFileSystem.Reload"/>
+        ModFileSystem = 0,
+    }
+
+    public ModDiscoveryFinished()
+        : base(nameof(ModDiscoveryFinished))
+    { }
+
+    public void Invoke()
+        => Invoke(this);
+}

Penumbra/Communication/ModDiscoveryStarted.cs

@@ -0,0 +1,26 @@
+using System;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary> Triggered whenever mods are prepared to be rediscovered. </summary>
+public sealed class ModDiscoveryStarted : EventWrapper<Action, ModDiscoveryStarted.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="Collections.Cache.CollectionCacheManager.OnModDiscoveryStarted"/>
+        CollectionCacheManager = 0,
+
+        /// <seealso cref="Collections.Manager.CollectionStorage.OnModDiscoveryStarted"/>
+        CollectionStorage = 0,
+
+        /// <seealso cref="UI.ModsTab.ModFileSystemSelector.StoreCurrentSelection"/>
+        ModFileSystemSelector = 200,
+    }
+    public ModDiscoveryStarted()
+        : base(nameof(ModDiscoveryStarted))
+    { }
+
+    public void Invoke()
+        => Invoke(this);
+}

Penumbra/Communication/ModOptionChanged.cs

@@ -0,0 +1,40 @@
+using System;
+using Penumbra.Mods;
+using Penumbra.Mods.Manager;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary>
+/// Triggered whenever an option of a mod is changed inside the mod.
+/// <list type="number">
+///     <item>Parameter is the type option change. </item>
+///     <item>Parameter is the changed mod. </item>
+///     <item>Parameter is the index of the changed group inside the mod. </item>
+///     <item>Parameter is the index of the changed option inside the group or -1 if it does not concern a specific option. </item>
+///     <item>Parameter is the index of the group an option was moved to. </item>
+/// </list> </summary>
+public sealed class ModOptionChanged : EventWrapper<Action<ModOptionChangeType, Mod, int, int, int>, ModOptionChanged.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="Collections.Cache.CollectionCacheManager.OnModOptionChange"/>
+        CollectionCacheManager = -100,
+
+        /// <seealso cref="Mods.Manager.ModCacheManager.OnModOptionChange"/>
+        ModCacheManager = 0,
+
+        /// <seealso cref="UI.AdvancedWindow.ItemSwapTab.OnModOptionChange"/>
+        ItemSwapTab = 0,
+
+        /// <seealso cref="Collections.Manager.CollectionStorage.OnModOptionChange"/>
+        CollectionStorage = 100,
+    }
+
+    public ModOptionChanged()
+        : base(nameof(ModOptionChanged))
+    { }
+
+    public void Invoke(ModOptionChangeType changeType, Mod mod, int groupIndex, int optionIndex, int moveToIndex)
+        => Invoke(this, changeType, mod, groupIndex, optionIndex, moveToIndex);
+}

Penumbra/Communication/ModPathChanged.cs

@@ -0,0 +1,54 @@
+using System;
+using System.IO;
+using Penumbra.Mods;
+using Penumbra.Mods.Manager;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary>
+/// Triggered whenever a mod is added, deleted, moved or reloaded.
+/// <list type="number">
+///     <item>Parameter is the type of change. </item>
+///     <item>Parameter is the changed mod. </item>
+///     <item>Parameter is the old directory on deletion, move or reload and null on addition. </item>
+///     <item>Parameter is the new directory on addition, move or reload and null on deletion. </item>
+/// </list>
+/// </summary>
+public sealed class ModPathChanged : EventWrapper<Action<ModPathChangeType, Mod, DirectoryInfo?, DirectoryInfo?>, ModPathChanged.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="Collections.Cache.CollectionCacheManager.OnModChangeAddition"/>
+        CollectionCacheManagerAddition = -100,
+
+        /// <seealso cref="Api.PenumbraApi.ModPathChangeSubscriber"/>
+        Api = 0,
+
+        /// <seealso cref="Mods.Manager.ModCacheManager.OnModPathChange"/>
+        ModCacheManager = 0,
+
+        /// <seealso cref="Mods.Manager.ModExportManager.OnModPathChange"/>
+        ModExportManager = 0,
+
+        /// <seealso cref="Mods.ModFileSystem.OnModPathChange"/>
+        ModFileSystem = 0,
+
+        /// <seealso cref="Mods.Manager.ModManager.OnModPathChange"/>
+        ModManager = 0,
+
+        /// <seealso cref="Collections.Manager.CollectionStorage.OnModPathChange"/>
+        CollectionStorage = 10,
+
+        /// <seealso cref="Collections.Cache.CollectionCacheManager.OnModChangeRemoval"/>
+        CollectionCacheManagerRemoval = 100,
+
+
+    }
+    public ModPathChanged()
+        : base(nameof(ModPathChanged))
+    { }
+
+    public void Invoke(ModPathChangeType changeType, Mod mod, DirectoryInfo? oldModDirectory, DirectoryInfo? newModDirectory)
+        => Invoke(this, changeType, mod, oldModDirectory, newModDirectory);
+}

Penumbra/Communication/ModSettingChanged.cs

@@ -0,0 +1,43 @@
+using System;
+using Penumbra.Api.Enums;
+using Penumbra.Collections;
+using Penumbra.Mods;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary>
+/// Triggered whenever a mod setting is changed.
+/// <list type="number">
+///     <item>Parameter is the collection in which the setting was changed. </item>
+///     <item>Parameter is the type of change. </item>
+///     <item>Parameter is the mod the setting was changed for, unless it was a multi-change. </item>
+///     <item>Parameter is the old value of the setting before the change as int. </item>
+///     <item>Parameter is the index of the changed group if the change type is Setting. </item>
+///     <item>Parameter is whether the change was inherited from another collection. </item>
+/// </list>
+/// </summary>
+public sealed class ModSettingChanged : EventWrapper<Action<ModCollection, ModSettingChange, Mod?, int, int, bool>, ModSettingChanged.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="Api.PenumbraApi.OnModSettingChange"/>
+        Api = int.MinValue,
+
+        /// <seealso cref="Collections.Cache.CollectionCacheManager.OnModSettingChange"/>
+        CollectionCacheManager = 0,
+
+        /// <seealso cref="UI.AdvancedWindow.ItemSwapTab.OnSettingChange"/>
+        ItemSwapTab = 0,
+
+        /// <seealso cref="UI.ModsTab.ModFileSystemSelector.OnSettingChange"/>
+        ModFileSystemSelector = 0,
+    }
+
+    public ModSettingChanged()
+        : base(nameof(ModSettingChanged))
+    { }
+
+    public void Invoke(ModCollection collection, ModSettingChange type, Mod? mod, int oldValue, int groupIdx, bool inherited)
+        => Invoke(this, collection, type, mod, oldValue, groupIdx, inherited);
+}

Penumbra/Communication/PostSettingsPanelDraw.cs

@@ -0,0 +1,26 @@
+using System;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary>
+/// Triggered after the settings panel is drawn.
+/// <list type="number">
+///     <item>Parameter is the identifier (directory name) of the currently selected mod. </item>
+/// </list>
+/// </summary>
+public sealed class PostSettingsPanelDraw : EventWrapper<Action<string>, PostSettingsPanelDraw.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="Api.PenumbraApi.PostSettingsPanelDraw"/>
+        Default = 0,
+    }
+
+    public PostSettingsPanelDraw()
+        : base(nameof(PostSettingsPanelDraw))
+    { }
+
+    public void Invoke(string modDirectory)
+        => Invoke(this, modDirectory);
+}

Penumbra/Communication/PreSettingsPanelDraw.cs

@@ -0,0 +1,26 @@
+using System;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary>
+/// Triggered before the settings panel is drawn.
+/// <list type="number">
+///     <item>Parameter is the identifier (directory name) of the currently selected mod. </item>
+/// </list>
+/// </summary>
+public sealed class PreSettingsPanelDraw : EventWrapper<Action<string>, PreSettingsPanelDraw.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="Api.PenumbraApi.PreSettingsPanelDraw"/>
+        Default = 0,
+    }
+
+    public PreSettingsPanelDraw()
+        : base(nameof(PreSettingsPanelDraw))
+    { }
+
+    public void Invoke(string modDirectory)
+        => Invoke(this, modDirectory);
+}

Penumbra/Communication/TemporaryGlobalModChange.cs

@@ -0,0 +1,31 @@
+using System;
+using Penumbra.Mods;
+using Penumbra.Util;
+
+namespace Penumbra.Communication;
+
+/// <summary>
+/// Triggered whenever a temporary mod for all collections is changed.
+/// <list type="number">
+///     <item>Parameter added, deleted or edited temporary mod.</item>
+///     <item>Parameter is whether the mod was newly created.</item>
+///     <item>Parameter is whether the mod was deleted.</item>
+/// </list> </summary>
+public sealed class TemporaryGlobalModChange : EventWrapper<Action<TemporaryMod, bool, bool>, TemporaryGlobalModChange.Priority>
+{
+    public enum Priority
+    {
+        /// <seealso cref="Collections.Cache.CollectionCacheManager.OnGlobalModChange"/>
+        CollectionCacheManager = 0,
+
+        /// <seealso cref="Collections.Manager.TempCollectionManager.OnGlobalModChange"/>
+        TempCollectionManager = 0,
+    }
+
+    public TemporaryGlobalModChange()
+        : base(nameof(TemporaryGlobalModChange))
+    { }
+
+    public void Invoke(TemporaryMod temporaryMod, bool newlyCreated, bool deleted)
+        => Invoke(this, temporaryMod, newlyCreated, deleted);
+}

Penumbra/Interop/PathResolving/IdentifiedCollectionCache.cs

@@ -5,7 +5,8 @@ using Dalamud.Game.ClientState;
 using FFXIVClientStructs.FFXIV.Client.Game.Character;
 using FFXIVClientStructs.FFXIV.Client.Game.Object;
 using Penumbra.Collections;
-using Penumbra.Collections.Manager;
+using Penumbra.Collections.Manager;
+using Penumbra.Communication;
 using Penumbra.GameData.Actors;
 using Penumbra.Interop.Services;
 using Penumbra.Services;
@@ -26,7 +27,7 @@ public unsafe class IdentifiedCollectionCache : IDisposable, IEnumerable<(nint A
         _communicator = communicator;
         _events       = events;
 
-        _communicator.CollectionChange.Subscribe(CollectionChangeClear);
+        _communicator.CollectionChange.Subscribe(CollectionChangeClear, CollectionChange.Priority.IdentifiedCollectionCache);
         _clientState.TerritoryChanged        += TerritoryClear;
         _events.CharacterDestructor          += OnCharacterDestruct;
     }

Penumbra/Mods/Manager/ModCacheManager.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Threading.Tasks;
+using Penumbra.Communication;
 using Penumbra.GameData;
 using Penumbra.GameData.Data;
 using Penumbra.GameData.Enums;
@@ -23,10 +24,10 @@ public class ModCacheManager : IDisposable
         _identifier   = identifier;
         _modManager   = modStorage;
 
-        _communicator.ModOptionChanged.Subscribe(OnModOptionChange);
-        _communicator.ModPathChanged.Subscribe(OnModPathChange);
-        _communicator.ModDataChanged.Subscribe(OnModDataChange);
-        _communicator.ModDiscoveryFinished.Subscribe(OnModDiscoveryFinished);
+        _communicator.ModOptionChanged.Subscribe(OnModOptionChange, ModOptionChanged.Priority.ModCacheManager);
+        _communicator.ModPathChanged.Subscribe(OnModPathChange, ModPathChanged.Priority.ModCacheManager);
+        _communicator.ModDataChanged.Subscribe(OnModDataChange, ModDataChanged.Priority.ModCacheManager);
+        _communicator.ModDiscoveryFinished.Subscribe(OnModDiscoveryFinished, ModDiscoveryFinished.Priority.ModCacheManager);
         if (!identifier.Valid)
             identifier.FinishedCreation += OnIdentifierCreation;
         OnModDiscoveryFinished();

Penumbra/Mods/Manager/ModExportManager.cs

@@ -1,5 +1,6 @@
 using System;
 using System.IO;
+using Penumbra.Communication;
 using Penumbra.Services;
 
 namespace Penumbra.Mods.Manager;
@@ -21,7 +22,7 @@ public class ModExportManager : IDisposable
         _communicator = communicator;
         _modManager   = modManager;
         UpdateExportDirectory(_config.ExportDirectory, false);
-        _communicator.ModPathChanged.Subscribe(OnModPathChange);
+        _communicator.ModPathChanged.Subscribe(OnModPathChange, ModPathChanged.Priority.ModExportManager);
     }
 
     /// <inheritdoc cref="UpdateExportDirectory(string, bool)"/>

Penumbra/Mods/Manager/ModFileSystem.cs

@@ -5,6 +5,7 @@ using System.IO;
 using System.Linq;
 using System.Text.RegularExpressions;
 using OtterGui.Filesystem;
+using Penumbra.Communication;
 using Penumbra.Mods.Manager;
 using Penumbra.Services;
 using Penumbra.Util;
@@ -25,9 +26,9 @@ public sealed class ModFileSystem : FileSystem<Mod>, IDisposable, ISavable
         _saveService  = saveService;
         Reload();
         Changed += OnChange;
-        _communicator.ModDiscoveryFinished.Subscribe(Reload);
-        _communicator.ModDataChanged.Subscribe(OnDataChange);
-        _communicator.ModPathChanged.Subscribe(OnModPathChange);
+        _communicator.ModDiscoveryFinished.Subscribe(Reload, ModDiscoveryFinished.Priority.ModFileSystem);
+        _communicator.ModDataChanged.Subscribe(OnDataChange, ModDataChanged.Priority.ModFileSystem);
+        _communicator.ModPathChanged.Subscribe(OnModPathChange, ModPathChanged.Priority.ModFileSystem);
     }
 
     public void Dispose()

Penumbra/Mods/Manager/ModManager.cs

@@ -3,6 +3,7 @@ using System.Collections.Concurrent;
 using System.IO;
 using System.Linq;
 using System.Threading.Tasks;
+using Penumbra.Communication;
 using Penumbra.Services;
 
 namespace Penumbra.Mods.Manager;
@@ -50,7 +51,7 @@ public sealed class ModManager : ModStorage, IDisposable
         OptionEditor  = optionEditor;
         Creator    = creator;
         SetBaseDirectory(config.ModDirectory, true);
-        _communicator.ModPathChanged.Subscribe(OnModPathChange);
+        _communicator.ModPathChanged.Subscribe(OnModPathChange, ModPathChanged.Priority.ModManager);
         DiscoverMods();
     }
 

Penumbra/Services/CommunicatorService.cs

@@ -1,350 +1,59 @@
 using System;
-using System.IO;
-using Penumbra.Api.Enums;
-using Penumbra.Collections;
-using Penumbra.Collections.Manager;
-using Penumbra.Mods;
-using Penumbra.Mods.Manager;
-using Penumbra.Util;
+using Penumbra.Communication;
 
 namespace Penumbra.Services;
 
-/// <summary>
-/// Triggered whenever collection setup is changed.
-/// <list type="number">
-///     <item>Parameter is the type of the changed collection. (Inactive or Temporary for additions or deletions)</item>
-///     <item>Parameter is the old collection, or null on additions.</item>
-///     <item>Parameter is the new collection, or null on deletions.</item>
-///     <item>Parameter is the display name for Individual collections or an empty string otherwise.</item>
-/// </list> </summary>
-public sealed class CollectionChange : EventWrapper<Action<CollectionType, ModCollection?, ModCollection?, string>>
-{
-    public CollectionChange()
-        : base(nameof(CollectionChange))
-    { }
-
-    public void Invoke(CollectionType collectionType, ModCollection? oldCollection, ModCollection? newCollection, string displayName)
-        => Invoke(this, collectionType, oldCollection, newCollection, displayName);
-}
-
-/// <summary>
-/// Triggered whenever a temporary mod for all collections is changed.
-/// <list type="number">
-///     <item>Parameter added, deleted or edited temporary mod.</item>
-///     <item>Parameter is whether the mod was newly created.</item>
-///     <item>Parameter is whether the mod was deleted.</item>
-/// </list> </summary>
-public sealed class TemporaryGlobalModChange : EventWrapper<Action<TemporaryMod, bool, bool>>
-{
-    public TemporaryGlobalModChange()
-        : base(nameof(TemporaryGlobalModChange))
-    { }
-
-    public void Invoke(TemporaryMod temporaryMod, bool newlyCreated, bool deleted)
-        => Invoke(this, temporaryMod, newlyCreated, deleted);
-}
-
-/// <summary>
-/// Triggered whenever a character base draw object is being created by the game.
-/// <list type="number">
-///     <item>Parameter is the game object for which a draw object is created. </item>
-///     <item>Parameter is the name of the applied collection. </item>
-///     <item>Parameter is a pointer to the model id (an uint). </item>
-///     <item>Parameter is a pointer to the customize array. </item>
-///     <item>Parameter is a pointer to the equip data array. </item>
-/// </list> </summary>
-public sealed class CreatingCharacterBase : EventWrapper<Action<nint, string, nint, nint, nint>>
-{
-    public CreatingCharacterBase()
-        : base(nameof(CreatingCharacterBase))
-    { }
-
-    public void Invoke(nint gameObject, string appliedCollectionName, nint modelIdAddress, nint customizeArrayAddress, nint equipDataAddress)
-        => Invoke(this, gameObject, appliedCollectionName, modelIdAddress, customizeArrayAddress, equipDataAddress);
-}
-
-/// <summary> <list type="number">
-///     <item>Parameter is the game object for which a draw object is created. </item>
-///     <item>Parameter is the name of the applied collection. </item>
-///     <item>Parameter is the created draw object. </item>
-/// </list> </summary>
-public sealed class CreatedCharacterBase : EventWrapper<Action<nint, string, nint>>
-{
-    public CreatedCharacterBase()
-        : base(nameof(CreatedCharacterBase))
-    { }
-
-    public void Invoke(nint gameObject, string appliedCollectionName, nint drawObject)
-        => Invoke(this, gameObject, appliedCollectionName, drawObject);
-}
-
-/// <summary>
-/// Triggered whenever mod meta data or local data is changed.
-/// <list type="number">
-///     <item>Parameter is the type of data change for the mod, which can be multiple flags. </item>
-///     <item>Parameter is the changed mod. </item>
-///     <item>Parameter is the old name of the mod in case of a name change, and null otherwise. </item>
-/// </list> </summary>
-public sealed class ModDataChanged : EventWrapper<Action<ModDataChangeType, Mod, string?>>
-{
-    public ModDataChanged()
-        : base(nameof(ModDataChanged))
-    { }
-
-    public void Invoke(ModDataChangeType changeType, Mod mod, string? oldName)
-        => Invoke(this, changeType, mod, oldName);
-}
-
-/// <summary>
-/// Triggered whenever an option of a mod is changed inside the mod.
-/// <list type="number">
-///     <item>Parameter is the type option change. </item>
-///     <item>Parameter is the changed mod. </item>
-///     <item>Parameter is the index of the changed group inside the mod. </item>
-///     <item>Parameter is the index of the changed option inside the group or -1 if it does not concern a specific option. </item>
-///     <item>Parameter is the index of the group an option was moved to. </item>
-/// </list> </summary>
-public sealed class ModOptionChanged : EventWrapper<Action<ModOptionChangeType, Mod, int, int, int>>
-{
-    public ModOptionChanged()
-        : base(nameof(ModOptionChanged))
-    { }
-
-    public void Invoke(ModOptionChangeType changeType, Mod mod, int groupIndex, int optionIndex, int moveToIndex)
-        => Invoke(this, changeType, mod, groupIndex, optionIndex, moveToIndex);
-}
-
-/// <summary> Triggered whenever mods are prepared to be rediscovered. </summary>
-public sealed class ModDiscoveryStarted : EventWrapper<Action>
-{
-    public ModDiscoveryStarted()
-        : base(nameof(ModDiscoveryStarted))
-    { }
-
-    public void Invoke()
-        => EventWrapper<Action>.Invoke(this);
-}
-
-/// <summary> Triggered whenever a new mod discovery has finished. </summary>
-public sealed class ModDiscoveryFinished : EventWrapper<Action>
-{
-    public ModDiscoveryFinished()
-        : base(nameof(ModDiscoveryFinished))
-    { }
-
-    public void Invoke()
-        => Invoke(this);
-}
-
-/// <summary>
-/// Triggered whenever the mod root directory changes.
-/// <list type="number">
-///     <item>Parameter is the full path of the new directory. </item>
-///     <item>Parameter is whether the new directory is valid. </item>
-/// </list>
-/// </summary>
-public sealed class ModDirectoryChanged : EventWrapper<Action<string, bool>>
-{
-    public ModDirectoryChanged()
-        : base(nameof(ModDirectoryChanged))
-    { }
-
-    public void Invoke(string newModDirectory, bool newDirectoryValid)
-        => Invoke(this, newModDirectory, newDirectoryValid);
-}
-
-/// <summary>
-/// Triggered whenever a mod is added, deleted, moved or reloaded.
-/// <list type="number">
-///     <item>Parameter is the type of change. </item>
-///     <item>Parameter is the changed mod. </item>
-///     <item>Parameter is the old directory on deletion, move or reload and null on addition. </item>
-///     <item>Parameter is the new directory on addition, move or reload and null on deletion. </item>
-/// </list>
-/// </summary>
-public sealed class ModPathChanged : EventWrapper<Action<ModPathChangeType, Mod, DirectoryInfo?, DirectoryInfo?>>
-{
-    public ModPathChanged()
-        : base(nameof(ModPathChanged))
-    { }
-
-    public void Invoke(ModPathChangeType changeType, Mod mod, DirectoryInfo? oldModDirectory, DirectoryInfo? newModDirectory)
-        => Invoke(this, changeType, mod, oldModDirectory, newModDirectory);
-}
-
-/// <summary>
-/// Triggered whenever a mod setting is changed.
-/// <list type="number">
-///     <item>Parameter is the collection in which the setting was changed. </item>
-///     <item>Parameter is the type of change. </item>
-///     <item>Parameter is the mod the setting was changed for, unless it was a multi-change. </item>
-///     <item>Parameter is the old value of the setting before the change as int. </item>
-///     <item>Parameter is the index of the changed group if the change type is Setting. </item>
-///     <item>Parameter is whether the change was inherited from another collection. </item>
-/// </list>
-/// </summary>
-public sealed class ModSettingChanged : EventWrapper<Action<ModCollection, ModSettingChange, Mod?, int, int, bool>>
-{
-    public ModSettingChanged()
-        : base(nameof(ModSettingChanged))
-    { }
-
-    public void Invoke(ModCollection collection, ModSettingChange type, Mod? mod, int oldValue, int groupIdx, bool inherited)
-        => Invoke(this, collection, type, mod, oldValue, groupIdx, inherited);
-}
-
-/// <summary>
-/// Triggered whenever a collections inheritances change.
-/// <list type="number">
-///     <item>Parameter is the collection whose ancestors were changed. </item>
-///     <item>Parameter is whether the change was itself inherited, i.e. if it happened in a direct parent (false) or a more removed ancestor (true). </item>
-/// </list>
-/// </summary>
-public sealed class CollectionInheritanceChanged : EventWrapper<Action<ModCollection, bool>>
-{
-    public CollectionInheritanceChanged()
-        : base(nameof(CollectionInheritanceChanged))
-    { }
-
-    public void Invoke(ModCollection collection, bool inherited)
-        => Invoke(this, collection, inherited);
-}
-
-/// <summary>
-/// Triggered when the general Enabled state of Penumbra is changed.
-/// <list type="number">
-///     <item>Parameter is whether Penumbra is now Enabled (true) or Disabled (false). </item>
-/// </list>
-/// </summary>
-public sealed class EnabledChanged : EventWrapper<Action<bool>>
-{
-    public EnabledChanged()
-        : base(nameof(EnabledChanged))
-    { }
-
-    public void Invoke(bool enabled)
-        => Invoke(this, enabled);
-}
-
-/// <summary>
-/// Triggered before the settings panel is drawn.
-/// <list type="number">
-///     <item>Parameter is the identifier (directory name) of the currently selected mod. </item>
-/// </list>
-/// </summary>
-public sealed class PreSettingsPanelDraw : EventWrapper<Action<string>>
-{
-    public PreSettingsPanelDraw()
-        : base(nameof(PreSettingsPanelDraw))
-    { }
-
-    public void Invoke(string modDirectory)
-        => Invoke(this, modDirectory);
-}
-
-/// <summary>
-/// Triggered after the settings panel is drawn.
-/// <list type="number">
-///     <item>Parameter is the identifier (directory name) of the currently selected mod. </item>
-/// </list>
-/// </summary>
-public sealed class PostSettingsPanelDraw : EventWrapper<Action<string>>
-{
-    public PostSettingsPanelDraw()
-        : base(nameof(PostSettingsPanelDraw))
-    { }
-
-    public void Invoke(string modDirectory)
-        => Invoke(this, modDirectory);
-}
-
-/// <summary>
-/// Triggered when a Changed Item in Penumbra is hovered.
-/// <list type="number">
-///     <item>Parameter is the hovered object data if any. </item>
-/// </list>
-/// </summary>
-public sealed class ChangedItemHover : EventWrapper<Action<object?>>
-{
-    public ChangedItemHover()
-        : base(nameof(ChangedItemHover))
-    { }
-
-    public void Invoke(object? data)
-        => Invoke(this, data);
-
-    public bool HasTooltip
-        => HasSubscribers;
-}
-
-/// <summary>
-/// Triggered when a Changed Item in Penumbra is clicked.
-/// <list type="number">
-///     <item>Parameter is the clicked mouse button. </item>
-///     <item>Parameter is the clicked object data if any.. </item>
-/// </list>
-/// </summary>
-public sealed class ChangedItemClick : EventWrapper<Action<MouseButton, object?>>
-{
-    public ChangedItemClick()
-        : base(nameof(ChangedItemClick))
-    { }
-
-    public void Invoke(MouseButton button, object? data)
-        => Invoke(this, button, data);
-}
-
 public class CommunicatorService : IDisposable
 {
-    /// <inheritdoc cref="Services.CollectionChange"/>
+    /// <inheritdoc cref="Communication.CollectionChange"/>
     public readonly CollectionChange CollectionChange = new();
 
-    /// <inheritdoc cref="Services.TemporaryGlobalModChange"/>
+    /// <inheritdoc cref="Communication.TemporaryGlobalModChange"/>
     public readonly TemporaryGlobalModChange TemporaryGlobalModChange = new();
 
-    /// <inheritdoc cref="Services.CreatingCharacterBase"/>
+    /// <inheritdoc cref="Communication.CreatingCharacterBase"/>
     public readonly CreatingCharacterBase CreatingCharacterBase = new();
 
-    /// <inheritdoc cref="Services.CreatedCharacterBase"/>
+    /// <inheritdoc cref="Communication.CreatedCharacterBase"/>
     public readonly CreatedCharacterBase CreatedCharacterBase = new();
 
-    /// <inheritdoc cref="Services.ModDataChanged"/>
+    /// <inheritdoc cref="Communication.ModDataChanged"/>
     public readonly ModDataChanged ModDataChanged = new();
 
-    /// <inheritdoc cref="Services.ModOptionChanged"/>
+    /// <inheritdoc cref="Communication.ModOptionChanged"/>
     public readonly ModOptionChanged ModOptionChanged = new();
 
-    /// <inheritdoc cref="Services.ModDiscoveryStarted"/>
+    /// <inheritdoc cref="Communication.ModDiscoveryStarted"/>
     public readonly ModDiscoveryStarted ModDiscoveryStarted = new();
 
-    /// <inheritdoc cref="Services.ModDiscoveryFinished"/>
+    /// <inheritdoc cref="Communication.ModDiscoveryFinished"/>
     public readonly ModDiscoveryFinished ModDiscoveryFinished = new();
 
-    /// <inheritdoc cref="Services.ModDirectoryChanged"/>
+    /// <inheritdoc cref="Communication.ModDirectoryChanged"/>
     public readonly ModDirectoryChanged ModDirectoryChanged = new();
 
-    /// <inheritdoc cref="Services.ModPathChanged"/>
+    /// <inheritdoc cref="Communication.ModPathChanged"/>
     public readonly ModPathChanged ModPathChanged = new();
 
-    /// <inheritdoc cref="Services.ModSettingChanged"/>
+    /// <inheritdoc cref="Communication.ModSettingChanged"/>
     public readonly ModSettingChanged ModSettingChanged = new();
 
-    /// <inheritdoc cref="Services.CollectionInheritanceChanged"/>
+    /// <inheritdoc cref="Communication.CollectionInheritanceChanged"/>
     public readonly CollectionInheritanceChanged CollectionInheritanceChanged = new();
 
-    /// <inheritdoc cref="Services.EnabledChanged"/>
+    /// <inheritdoc cref="Communication.EnabledChanged"/>
     public readonly EnabledChanged EnabledChanged = new();
 
-    /// <inheritdoc cref="Services.PreSettingsPanelDraw"/>
+    /// <inheritdoc cref="Communication.PreSettingsPanelDraw"/>
     public readonly PreSettingsPanelDraw PreSettingsPanelDraw = new();
 
-    /// <inheritdoc cref="Services.PostSettingsPanelDraw"/>
+    /// <inheritdoc cref="Communication.PostSettingsPanelDraw"/>
     public readonly PostSettingsPanelDraw PostSettingsPanelDraw = new();
 
-    /// <inheritdoc cref="Services.ChangedItemHover"/>
+    /// <inheritdoc cref="Communication.ChangedItemHover"/>
     public readonly ChangedItemHover ChangedItemHover = new();
 
-    /// <inheritdoc cref="Services.ChangedItemClick"/>
+    /// <inheritdoc cref="Communication.ChangedItemClick"/>
     public readonly ChangedItemClick ChangedItemClick = new();
 
     public void Dispose()

Penumbra/UI/AdvancedWindow/ItemSwapTab.cs

@@ -13,6 +13,7 @@ using OtterGui.Widgets;
 using Penumbra.Api.Enums;
 using Penumbra.Collections;
 using Penumbra.Collections.Manager;
+using Penumbra.Communication;
 using Penumbra.GameData.Enums;
 using Penumbra.GameData.Structs;
 using Penumbra.Meta;
@@ -57,10 +58,10 @@ public class ItemSwapTab : IDisposable, ITab
             // @formatter:on
         };
 
-        _communicator.CollectionChange.Subscribe(OnCollectionChange);
-        _communicator.ModSettingChanged.Subscribe(OnSettingChange);
-        _communicator.CollectionInheritanceChanged.Subscribe(OnInheritanceChange);
-        _communicator.ModOptionChanged.Subscribe(OnModOptionChange);
+        _communicator.CollectionChange.Subscribe(OnCollectionChange, CollectionChange.Priority.ItemSwapTab);
+        _communicator.ModSettingChanged.Subscribe(OnSettingChange, ModSettingChanged.Priority.ItemSwapTab);
+        _communicator.CollectionInheritanceChanged.Subscribe(OnInheritanceChange, CollectionInheritanceChanged.Priority.ItemSwapTab);
+        _communicator.ModOptionChanged.Subscribe(OnModOptionChange, ModOptionChanged.Priority.ItemSwapTab);
     }
 
     /// <summary> Update the currently selected mod or its settings. </summary>

Penumbra/UI/CollectionTab/CollectionSelector.cs

@@ -6,6 +6,7 @@ using OtterGui;
 using OtterGui.Raii;
 using Penumbra.Collections;
 using Penumbra.Collections.Manager;
+using Penumbra.Communication;
 using Penumbra.GameData.Actors;
 using Penumbra.Services;
 using Penumbra.UI.Classes;
@@ -34,7 +35,7 @@ public sealed class CollectionSelector : ItemSelector<ModCollection>, IDisposabl
         _active       = active;
         _tutorial     = tutorial;
 
-        _communicator.CollectionChange.Subscribe(OnCollectionChange);
+        _communicator.CollectionChange.Subscribe(OnCollectionChange, CollectionChange.Priority.CollectionSelector);
         // Set items.
         OnCollectionChange(CollectionType.Inactive, null, null, string.Empty);
         // Set selection.

Penumbra/UI/CollectionTab/IndividualAssignmentUi.cs

@@ -5,6 +5,7 @@ using ImGuiNET;
 using OtterGui.Raii;
 using Penumbra.Collections;
 using Penumbra.Collections.Manager;
+using Penumbra.Communication;
 using Penumbra.GameData.Actors;
 using Penumbra.Services;
 
@@ -30,7 +31,7 @@ public class IndividualAssignmentUi : IDisposable
         _communicator      = communicator;
         _actorService      = actors;
         _collectionManager = collectionManager;
-        _communicator.CollectionChange.Subscribe(UpdateIdentifiers);
+        _communicator.CollectionChange.Subscribe(UpdateIdentifiers, CollectionChange.Priority.IndividualAssignmentUi);
         if (_actorService.Valid)
             SetupCombos();
         else
@@ -57,7 +58,7 @@ public class IndividualAssignmentUi : IDisposable
     public void DrawWorldCombo(float width)
     {
         if (_ready && _worldCombo.Draw(width))
-            UpdateIdentifiers();
+            UpdateIdentifiersInternal();
     }
 
     public void DrawObjectKindCombo(float width)
@@ -76,7 +77,7 @@ public class IndividualAssignmentUi : IDisposable
                 continue;
 
             _newKind = kind;
-            UpdateIdentifiers();
+            UpdateIdentifiersInternal();
         }
     }
 
@@ -87,7 +88,7 @@ public class IndividualAssignmentUi : IDisposable
 
         ImGui.SetNextItemWidth(width);
         if (ImGui.InputTextWithHint("##NewCharacter", "Character Name...", ref _newCharacterName, 32))
-            UpdateIdentifiers();
+            UpdateIdentifiersInternal();
     }
 
     public void DrawNewNpcCollection(float width)
@@ -97,7 +98,7 @@ public class IndividualAssignmentUi : IDisposable
 
         var combo = GetNpcCombo(_newKind);
         if (combo.Draw(width))
-            UpdateIdentifiers();
+            UpdateIdentifiersInternal();
     }
 
     public void Dispose()
@@ -154,10 +155,10 @@ public class IndividualAssignmentUi : IDisposable
     private void UpdateIdentifiers(CollectionType type, ModCollection? _1, ModCollection? _2, string _3)
     {
         if (type == CollectionType.Individual)
-            UpdateIdentifiers();
+            UpdateIdentifiersInternal();
     }
 
-    private void UpdateIdentifiers()
+    private void UpdateIdentifiersInternal()
     {
         var combo = GetNpcCombo(_newKind);
         PlayerTooltip = _collectionManager.Active.Individuals.CanAdd(IdentifierType.Player, _newCharacterName,

Penumbra/UI/FileDialogService.cs

@@ -9,6 +9,7 @@ using Dalamud.Interface.ImGuiFileDialog;
 using Dalamud.Utility;
 using ImGuiNET;
 using OtterGui;
+using Penumbra.Communication;
 using Penumbra.Services;
 
 namespace Penumbra.UI;
@@ -22,9 +23,9 @@ public class FileDialogService : IDisposable
 
     public FileDialogService(CommunicatorService communicator, Configuration config)
     {
-        _communicator                           =  communicator;
-        _manager                                =  SetupFileManager(config.ModDirectory);
-        _communicator.ModDirectoryChanged.Subscribe(OnModDirectoryChange);
+        _communicator = communicator;
+        _manager      = SetupFileManager(config.ModDirectory);
+        _communicator.ModDirectoryChanged.Subscribe(OnModDirectoryChange, ModDirectoryChanged.Priority.FileDialogService);
     }
 
     public void OpenFilePicker(string title, string filters, Action<bool, List<string>> callback, int selectionCountMax, string? startPath,

Penumbra/UI/ModsTab/ModFileSystemSelector.cs

@@ -14,6 +14,7 @@ using OtterGui.Raii;
 using Penumbra.Api.Enums;
 using Penumbra.Collections;
 using Penumbra.Collections.Manager;
+using Penumbra.Communication;
 using Penumbra.Mods;
 using Penumbra.Mods.Manager;
 using Penumbra.Services;
@@ -72,12 +73,12 @@ public sealed class ModFileSystemSelector : FileSystemSelector<Mod, ModFileSyste
         SetFilterTooltip();
 
         SelectionChanged += OnSelectionChange;
-        _communicator.CollectionChange.Subscribe(OnCollectionChange);
-        _communicator.ModSettingChanged.Subscribe(OnSettingChange);
-        _communicator.CollectionInheritanceChanged.Subscribe(OnInheritanceChange);
-        _communicator.ModDataChanged.Subscribe(OnModDataChange);
-        _communicator.ModDiscoveryStarted.Subscribe(StoreCurrentSelection);
-        _communicator.ModDiscoveryFinished.Subscribe(RestoreLastSelection);
+        _communicator.CollectionChange.Subscribe(OnCollectionChange, CollectionChange.Priority.ModFileSystemSelector);
+        _communicator.ModSettingChanged.Subscribe(OnSettingChange, ModSettingChanged.Priority.ModFileSystemSelector);
+        _communicator.CollectionInheritanceChanged.Subscribe(OnInheritanceChange, CollectionInheritanceChanged.Priority.ModFileSystemSelector);
+        _communicator.ModDataChanged.Subscribe(OnModDataChange, ModDataChanged.Priority.ModFileSystemSelector);
+        _communicator.ModDiscoveryStarted.Subscribe(StoreCurrentSelection, ModDiscoveryStarted.Priority.ModFileSystemSelector);
+        _communicator.ModDiscoveryFinished.Subscribe(RestoreLastSelection, ModDiscoveryFinished.Priority.ModFileSystemSelector);
         OnCollectionChange(CollectionType.Current, null, _collectionManager.Active.Current, "");
     }
 

Penumbra/Util/EventWrapper.cs

@@ -4,10 +4,12 @@ using System.Linq;
 
 namespace Penumbra.Util;
 
-public abstract class EventWrapper<T> : IDisposable where T : Delegate
+public abstract class EventWrapper<T, TPriority> : IDisposable
+    where T : Delegate
+    where TPriority : struct, Enum
 {
-    private readonly string                                  _name;
-    private readonly List<(object Subscriber, int Priority)> _event = new();
+    private readonly string                                        _name;
+    private readonly List<(object Subscriber, TPriority Priority)> _event = new();
 
     public bool HasSubscribers
         => _event.Count > 0;
@@ -23,12 +25,12 @@ public abstract class EventWrapper<T> : IDisposable where T : Delegate
         }
     }
 
-    public void Subscribe(T subscriber, int priority = 0)
+    public void Subscribe(T subscriber, TPriority priority)
     {
         lock (_event)
         {
-            var existingIdx = _event.FindIndex(p => (T) p.Subscriber == subscriber);
-            var idx         = _event.FindIndex(p => p.Priority > priority);
+            var existingIdx = _event.FindIndex(p => (T)p.Subscriber == subscriber);
+            var idx         = _event.FindIndex(p => p.Priority.CompareTo(priority) > 0);
             if (idx == existingIdx)
             {
                 if (idx < 0)
@@ -53,14 +55,14 @@ public abstract class EventWrapper<T> : IDisposable where T : Delegate
     {
         lock (_event)
         {
-            var idx = _event.FindIndex(p => (T) p.Subscriber == subscriber);
+            var idx = _event.FindIndex(p => (T)p.Subscriber == subscriber);
             if (idx >= 0)
                 _event.RemoveAt(idx);
         }
     }
 
 
-    protected static void Invoke(EventWrapper<T> wrapper)
+    protected static void Invoke(EventWrapper<T, TPriority> wrapper)
     {
         lock (wrapper._event)
         {
@@ -78,7 +80,7 @@ public abstract class EventWrapper<T> : IDisposable where T : Delegate
         }
     }
 
-    protected static void Invoke<T1>(EventWrapper<T> wrapper, T1 a)
+    protected static void Invoke<T1>(EventWrapper<T, TPriority> wrapper, T1 a)
     {
         lock (wrapper._event)
         {
@@ -96,7 +98,7 @@ public abstract class EventWrapper<T> : IDisposable where T : Delegate
         }
     }
 
-    protected static void Invoke<T1, T2>(EventWrapper<T> wrapper, T1 a, T2 b)
+    protected static void Invoke<T1, T2>(EventWrapper<T, TPriority> wrapper, T1 a, T2 b)
     {
         lock (wrapper._event)
         {
@@ -114,7 +116,7 @@ public abstract class EventWrapper<T> : IDisposable where T : Delegate
         }
     }
 
-    protected static void Invoke<T1, T2, T3>(EventWrapper<T> wrapper, T1 a, T2 b, T3 c)
+    protected static void Invoke<T1, T2, T3>(EventWrapper<T, TPriority> wrapper, T1 a, T2 b, T3 c)
     {
         lock (wrapper._event)
         {
@@ -132,7 +134,7 @@ public abstract class EventWrapper<T> : IDisposable where T : Delegate
         }
     }
 
-    protected static void Invoke<T1, T2, T3, T4>(EventWrapper<T> wrapper, T1 a, T2 b, T3 c, T4 d)
+    protected static void Invoke<T1, T2, T3, T4>(EventWrapper<T, TPriority> wrapper, T1 a, T2 b, T3 c, T4 d)
     {
         lock (wrapper._event)
         {
@@ -150,7 +152,7 @@ public abstract class EventWrapper<T> : IDisposable where T : Delegate
         }
     }
 
-    protected static void Invoke<T1, T2, T3, T4, T5>(EventWrapper<T> wrapper, T1 a, T2 b, T3 c, T4 d, T5 e)
+    protected static void Invoke<T1, T2, T3, T4, T5>(EventWrapper<T, TPriority> wrapper, T1 a, T2 b, T3 c, T4 d, T5 e)
     {
         lock (wrapper._event)
         {
@@ -168,7 +170,7 @@ public abstract class EventWrapper<T> : IDisposable where T : Delegate
         }
     }
 
-    protected static void Invoke<T1, T2, T3, T4, T5, T6>(EventWrapper<T> wrapper, T1 a, T2 b, T3 c, T4 d, T5 e, T6 f)
+    protected static void Invoke<T1, T2, T3, T4, T5, T6>(EventWrapper<T, TPriority> wrapper, T1 a, T2 b, T3 c, T4 d, T5 e, T6 f)
     {
         lock (wrapper._event)
         {