Merge branch 'develop' into stable

23 files changed, 1046 insertions, 122 deletions

diff --git a/src/SMAPI/Framework/Content/ContentCache.cs b/src/SMAPI/Framework/Content/ContentCache.cs
index f33ff84d..b0933ac6 100644
--- a/src/SMAPI/Framework/Content/ContentCache.cs
+++ b/src/SMAPI/Framework/Content/ContentCache.cs
@@ -4,7 +4,6 @@ using System.Diagnostics.Contracts;
 using System.Linq;
 using Microsoft.Xna.Framework;
 using StardewModdingAPI.Framework.Reflection;
-using StardewModdingAPI.Internal;
 using StardewModdingAPI.Toolkit.Utilities;
 using StardewValley;
 
diff --git a/src/SMAPI/Framework/ContentCoordinator.cs b/src/SMAPI/Framework/ContentCoordinator.cs
index 82d3805b..2fd31263 100644
--- a/src/SMAPI/Framework/ContentCoordinator.cs
+++ b/src/SMAPI/Framework/ContentCoordinator.cs
@@ -1,8 +1,10 @@
 using System;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 using System.Globalization;
 using System.IO;
 using System.Linq;
+using System.Threading;
 using Microsoft.Xna.Framework.Content;
 using StardewModdingAPI.Framework.Content;
 using StardewModdingAPI.Framework.ContentManagers;
@@ -48,6 +50,10 @@ namespace StardewModdingAPI.Framework
         /// <summary>Whether the content coordinator has been disposed.</summary>
         private bool IsDisposed;
 
+        /// <summary>A lock used to prevent asynchronous changes to the content manager list.</summary>
+        /// <remarks>The game may adds content managers in asynchronous threads (e.g. when populating the load screen).</remarks>
+        private readonly ReaderWriterLockSlim ContentManagerLock = new ReaderWriterLockSlim();
+
 
         /*********
         ** Accessors
@@ -59,10 +65,10 @@ namespace StardewModdingAPI.Framework
         public LocalizedContentManager.LanguageCode Language => this.MainContentManager.Language;
 
         /// <summary>Interceptors which provide the initial versions of matching assets.</summary>
-        public IDictionary<IModMetadata, IList<IAssetLoader>> Loaders { get; } = new Dictionary<IModMetadata, IList<IAssetLoader>>();
+        public IList<ModLinked<IAssetLoader>> Loaders { get; } = new List<ModLinked<IAssetLoader>>();
 
         /// <summary>Interceptors which edit matching assets after they're loaded.</summary>
-        public IDictionary<IModMetadata, IList<IAssetEditor>> Editors { get; } = new Dictionary<IModMetadata, IList<IAssetEditor>>();
+        public IList<ModLinked<IAssetEditor>> Editors { get; } = new List<ModLinked<IAssetEditor>>();
 
         /// <summary>The absolute path to the <see cref="ContentManager.RootDirectory"/>.</summary>
         public string FullRootDirectory { get; }
@@ -96,9 +102,12 @@ namespace StardewModdingAPI.Framework
         /// <param name="name">A name for the mod manager. Not guaranteed to be unique.</param>
         public GameContentManager CreateGameContentManager(string name)
         {
-            GameContentManager manager = new GameContentManager(name, this.MainContentManager.ServiceProvider, this.MainContentManager.RootDirectory, this.MainContentManager.CurrentCulture, this, this.Monitor, this.Reflection, this.OnDisposing, this.OnLoadingFirstAsset);
-            this.ContentManagers.Add(manager);
-            return manager;
+            return this.ContentManagerLock.InWriteLock(() =>
+            {
+                GameContentManager manager = new GameContentManager(name, this.MainContentManager.ServiceProvider, this.MainContentManager.RootDirectory, this.MainContentManager.CurrentCulture, this, this.Monitor, this.Reflection, this.OnDisposing, this.OnLoadingFirstAsset);
+                this.ContentManagers.Add(manager);
+                return manager;
+            });
         }
 
         /// <summary>Get a new content manager which handles reading files from a SMAPI mod folder with support for unpacked files.</summary>
@@ -107,20 +116,23 @@ namespace StardewModdingAPI.Framework
         /// <param name="gameContentManager">The game content manager used for map tilesheets not provided by the mod.</param>
         public ModContentManager CreateModContentManager(string name, string rootDirectory, IContentManager gameContentManager)
         {
-            ModContentManager manager = new ModContentManager(
-                name: name,
-                gameContentManager: gameContentManager,
-                serviceProvider: this.MainContentManager.ServiceProvider,
-                rootDirectory: rootDirectory,
-                currentCulture: this.MainContentManager.CurrentCulture,
-                coordinator: this,
-                monitor: this.Monitor,
-                reflection: this.Reflection,
-                jsonHelper: this.JsonHelper,
-                onDisposing: this.OnDisposing
-            );
-            this.ContentManagers.Add(manager);
-            return manager;
+            return this.ContentManagerLock.InWriteLock(() =>
+            {
+                ModContentManager manager = new ModContentManager(
+                    name: name,
+                    gameContentManager: gameContentManager,
+                    serviceProvider: this.MainContentManager.ServiceProvider,
+                    rootDirectory: rootDirectory,
+                    currentCulture: this.MainContentManager.CurrentCulture,
+                    coordinator: this,
+                    monitor: this.Monitor,
+                    reflection: this.Reflection,
+                    jsonHelper: this.JsonHelper,
+                    onDisposing: this.OnDisposing
+                );
+                this.ContentManagers.Add(manager);
+                return manager;
+            });
         }
 
         /// <summary>Get the current content locale.</summary>
@@ -132,8 +144,11 @@ namespace StardewModdingAPI.Framework
         /// <summary>Perform any cleanup needed when the locale changes.</summary>
         public void OnLocaleChanged()
         {
-            foreach (IContentManager contentManager in this.ContentManagers)
-                contentManager.OnLocaleChanged();
+            this.ContentManagerLock.InReadLock(() =>
+            {
+                foreach (IContentManager contentManager in this.ContentManagers)
+                    contentManager.OnLocaleChanged();
+            });
         }
 
         /// <summary>Get whether this asset is mapped to a mod folder.</summary>
@@ -180,7 +195,9 @@ namespace StardewModdingAPI.Framework
         public T LoadManagedAsset<T>(string contentManagerID, string relativePath)
         {
             // get content manager
-            IContentManager contentManager = this.ContentManagers.FirstOrDefault(p => p.IsNamespaced && p.Name == contentManagerID);
+            IContentManager contentManager = this.ContentManagerLock.InReadLock(() =>
+                this.ContentManagers.FirstOrDefault(p => p.IsNamespaced && p.Name == contentManagerID)
+            );
             if (contentManager == null)
                 throw new InvalidOperationException($"The '{contentManagerID}' prefix isn't handled by any mod.");
 
@@ -210,15 +227,18 @@ namespace StardewModdingAPI.Framework
         {
             // invalidate cache & track removed assets
             IDictionary<string, ISet<object>> removedAssets = new Dictionary<string, ISet<object>>(StringComparer.InvariantCultureIgnoreCase);
-            foreach (IContentManager contentManager in this.ContentManagers)
+            this.ContentManagerLock.InReadLock(() =>
             {
-                foreach (var entry in contentManager.InvalidateCache(predicate, dispose))
+                foreach (IContentManager contentManager in this.ContentManagers)
                 {
-                    if (!removedAssets.TryGetValue(entry.Key, out ISet<object> assets))
-                        removedAssets[entry.Key] = assets = new HashSet<object>(new ObjectReferenceComparer<object>());
-                    assets.Add(entry.Value);
+                    foreach (var entry in contentManager.InvalidateCache(predicate, dispose))
+                    {
+                        if (!removedAssets.TryGetValue(entry.Key, out ISet<object> assets))
+                            removedAssets[entry.Key] = assets = new HashSet<object>(new ObjectReferenceComparer<object>());
+                        assets.Add(entry.Value);
+                    }
                 }
-            }
+            });
 
             // reload core game assets
             if (removedAssets.Any())
@@ -232,6 +252,23 @@ namespace StardewModdingAPI.Framework
             return removedAssets.Keys;
         }
 
+        /// <summary>Get all loaded instances of an asset name.</summary>
+        /// <param name="assetName">The asset name.</param>
+        [SuppressMessage("ReSharper", "UnusedMember.Global", Justification = "This method is provided for Content Patcher.")]
+        public IEnumerable<object> GetLoadedValues(string assetName)
+        {
+            return this.ContentManagerLock.InReadLock(() =>
+            {
+                List<object> values = new List<object>();
+                foreach (IContentManager content in this.ContentManagers.Where(p => !p.IsNamespaced && p.IsLoaded(assetName)))
+                {
+                    object value = content.Load<object>(assetName, this.Language, useCache: true);
+                    values.Add(value);
+                }
+                return values;
+            });
+        }
+
         /// <summary>Dispose held resources.</summary>
         public void Dispose()
         {
@@ -244,6 +281,8 @@ namespace StardewModdingAPI.Framework
                 contentManager.Dispose();
             this.ContentManagers.Clear();
             this.MainContentManager = null;
+
+            this.ContentManagerLock.Dispose();
         }
 
 
@@ -257,7 +296,9 @@ namespace StardewModdingAPI.Framework
             if (this.IsDisposed)
                 return;
 
-            this.ContentManagers.Remove(contentManager);
+            this.ContentManagerLock.InWriteLock(() =>
+                this.ContentManagers.Remove(contentManager)
+            );
         }
     }
 }
diff --git a/src/SMAPI/Framework/ContentManagers/GameContentManager.cs b/src/SMAPI/Framework/ContentManagers/GameContentManager.cs
index 8930267d..eecdda74 100644
--- a/src/SMAPI/Framework/ContentManagers/GameContentManager.cs
+++ b/src/SMAPI/Framework/ContentManagers/GameContentManager.cs
@@ -21,10 +21,10 @@ namespace StardewModdingAPI.Framework.ContentManagers
         private readonly ContextHash<string> AssetsBeingLoaded = new ContextHash<string>();
 
         /// <summary>Interceptors which provide the initial versions of matching assets.</summary>
-        private IDictionary<IModMetadata, IList<IAssetLoader>> Loaders => this.Coordinator.Loaders;
+        private IList<ModLinked<IAssetLoader>> Loaders => this.Coordinator.Loaders;
 
         /// <summary>Interceptors which edit matching assets after they're loaded.</summary>
-        private IDictionary<IModMetadata, IList<IAssetEditor>> Editors => this.Coordinator.Editors;
+        private IList<ModLinked<IAssetEditor>> Editors => this.Coordinator.Editors;
 
         /// <summary>A lookup which indicates whether the asset is localizable (i.e. the filename contains the locale), if previously loaded.</summary>
         private readonly IDictionary<string, bool> IsLocalizableLookup;
@@ -278,16 +278,16 @@ namespace StardewModdingAPI.Framework.ContentManagers
         private IAssetData ApplyLoader<T>(IAssetInfo info)
         {
             // find matching loaders
-            var loaders = this.GetInterceptors(this.Loaders)
+            var loaders = this.Loaders
                 .Where(entry =>
                 {
                     try
                     {
-                        return entry.Value.CanLoad<T>(info);
+                        return entry.Data.CanLoad<T>(info);
                     }
                     catch (Exception ex)
                     {
-                        entry.Key.LogAsMod($"Mod failed when checking whether it could load asset '{info.AssetName}', and will be ignored. Error details:\n{ex.GetLogSummary()}", LogLevel.Error);
+                        entry.Mod.LogAsMod($"Mod failed when checking whether it could load asset '{info.AssetName}', and will be ignored. Error details:\n{ex.GetLogSummary()}", LogLevel.Error);
                         return false;
                     }
                 })
@@ -298,14 +298,14 @@ namespace StardewModdingAPI.Framework.ContentManagers
                 return null;
             if (loaders.Length > 1)
             {
-                string[] loaderNames = loaders.Select(p => p.Key.DisplayName).ToArray();
+                string[] loaderNames = loaders.Select(p => p.Mod.DisplayName).ToArray();
                 this.Monitor.Log($"Multiple mods want to provide the '{info.AssetName}' asset ({string.Join(", ", loaderNames)}), but an asset can't be loaded multiple times. SMAPI will use the default asset instead; uninstall one of the mods to fix this. (Message for modders: you should usually use {typeof(IAssetEditor)} instead to avoid conflicts.)", LogLevel.Warn);
                 return null;
             }
 
             // fetch asset from loader
-            IModMetadata mod = loaders[0].Key;
-            IAssetLoader loader = loaders[0].Value;
+            IModMetadata mod = loaders[0].Mod;
+            IAssetLoader loader = loaders[0].Data;
             T data;
             try
             {
@@ -338,11 +338,11 @@ namespace StardewModdingAPI.Framework.ContentManagers
             IAssetData GetNewData(object data) => new AssetDataForObject(info, data, this.AssertAndNormalizeAssetName);
 
             // edit asset
-            foreach (var entry in this.GetInterceptors(this.Editors))
+            foreach (var entry in this.Editors)
             {
                 // check for match
-                IModMetadata mod = entry.Key;
-                IAssetEditor editor = entry.Value;
+                IModMetadata mod = entry.Mod;
+                IAssetEditor editor = entry.Data;
                 try
                 {
                     if (!editor.CanEdit<T>(info))
@@ -382,19 +382,5 @@ namespace StardewModdingAPI.Framework.ContentManagers
             // return result
             return asset;
         }
-
-        /// <summary>Get all registered interceptors from a list.</summary>
-        private IEnumerable<KeyValuePair<IModMetadata, T>> GetInterceptors<T>(IDictionary<IModMetadata, IList<T>> entries)
-        {
-            foreach (var entry in entries)
-            {
-                IModMetadata mod = entry.Key;
-                IList<T> interceptors = entry.Value;
-
-                // registered editors
-                foreach (T interceptor in interceptors)
-                    yield return new KeyValuePair<IModMetadata, T>(mod, interceptor);
-            }
-        }
     }
 }
diff --git a/src/SMAPI/Framework/ContentManagers/ModContentManager.cs b/src/SMAPI/Framework/ContentManagers/ModContentManager.cs
index fdf76b24..0a526fc8 100644
--- a/src/SMAPI/Framework/ContentManagers/ModContentManager.cs
+++ b/src/SMAPI/Framework/ContentManagers/ModContentManager.cs
@@ -154,6 +154,7 @@ namespace StardewModdingAPI.Framework.ContentManagers
 
                     // unpacked map
                     case ".tbin":
+                    case ".tmx":
                         {
                             // validate
                             if (typeof(T) != typeof(Map))
diff --git a/src/SMAPI/Framework/Events/EventManager.cs b/src/SMAPI/Framework/Events/EventManager.cs
index 892cbc7b..a9dfda97 100644
--- a/src/SMAPI/Framework/Events/EventManager.cs
+++ b/src/SMAPI/Framework/Events/EventManager.cs
@@ -1,5 +1,8 @@
+using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
+using System.Reflection;
 using StardewModdingAPI.Events;
+using StardewModdingAPI.Framework.PerformanceMonitoring;
 
 namespace StardewModdingAPI.Framework.Events
 {
@@ -173,28 +176,32 @@ namespace StardewModdingAPI.Framework.Events
         /// <summary>Construct an instance.</summary>
         /// <param name="monitor">Writes messages to the log.</param>
         /// <param name="modRegistry">The mod registry with which to identify mods.</param>
-        public EventManager(IMonitor monitor, ModRegistry modRegistry)
+        /// <param name="performanceMonitor">Tracks performance metrics.</param>
+        public EventManager(IMonitor monitor, ModRegistry modRegistry, PerformanceMonitor performanceMonitor)
         {
             // create shortcut initializers
-            ManagedEvent<TEventArgs> ManageEventOf<TEventArgs>(string typeName, string eventName) => new ManagedEvent<TEventArgs>($"{typeName}.{eventName}", monitor, modRegistry);
+            ManagedEvent<TEventArgs> ManageEventOf<TEventArgs>(string typeName, string eventName, bool isPerformanceCritical = false)
+            {
+                return new ManagedEvent<TEventArgs>($"{typeName}.{eventName}", monitor, modRegistry, performanceMonitor, isPerformanceCritical);
+            }
 
             // init events (new)
             this.MenuChanged = ManageEventOf<MenuChangedEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.MenuChanged));
-            this.Rendering = ManageEventOf<RenderingEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.Rendering));
-            this.Rendered = ManageEventOf<RenderedEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.Rendered));
-            this.RenderingWorld = ManageEventOf<RenderingWorldEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.RenderingWorld));
-            this.RenderedWorld = ManageEventOf<RenderedWorldEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.RenderedWorld));
-            this.RenderingActiveMenu = ManageEventOf<RenderingActiveMenuEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.RenderingActiveMenu));
-            this.RenderedActiveMenu = ManageEventOf<RenderedActiveMenuEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.RenderedActiveMenu));
-            this.RenderingHud = ManageEventOf<RenderingHudEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.RenderingHud));
-            this.RenderedHud = ManageEventOf<RenderedHudEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.RenderedHud));
+            this.Rendering = ManageEventOf<RenderingEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.Rendering), isPerformanceCritical: true);
+            this.Rendered = ManageEventOf<RenderedEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.Rendered), isPerformanceCritical: true);
+            this.RenderingWorld = ManageEventOf<RenderingWorldEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.RenderingWorld), isPerformanceCritical: true);
+            this.RenderedWorld = ManageEventOf<RenderedWorldEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.RenderedWorld), isPerformanceCritical: true);
+            this.RenderingActiveMenu = ManageEventOf<RenderingActiveMenuEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.RenderingActiveMenu), isPerformanceCritical: true);
+            this.RenderedActiveMenu = ManageEventOf<RenderedActiveMenuEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.RenderedActiveMenu), isPerformanceCritical: true);
+            this.RenderingHud = ManageEventOf<RenderingHudEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.RenderingHud), isPerformanceCritical: true);
+            this.RenderedHud = ManageEventOf<RenderedHudEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.RenderedHud), isPerformanceCritical: true);
             this.WindowResized = ManageEventOf<WindowResizedEventArgs>(nameof(IModEvents.Display), nameof(IDisplayEvents.WindowResized));
 
             this.GameLaunched = ManageEventOf<GameLaunchedEventArgs>(nameof(IModEvents.GameLoop), nameof(IGameLoopEvents.GameLaunched));
-            this.UpdateTicking = ManageEventOf<UpdateTickingEventArgs>(nameof(IModEvents.GameLoop), nameof(IGameLoopEvents.UpdateTicking));
-            this.UpdateTicked = ManageEventOf<UpdateTickedEventArgs>(nameof(IModEvents.GameLoop), nameof(IGameLoopEvents.UpdateTicked));
-            this.OneSecondUpdateTicking = ManageEventOf<OneSecondUpdateTickingEventArgs>(nameof(IModEvents.GameLoop), nameof(IGameLoopEvents.OneSecondUpdateTicking));
-            this.OneSecondUpdateTicked = ManageEventOf<OneSecondUpdateTickedEventArgs>(nameof(IModEvents.GameLoop), nameof(IGameLoopEvents.OneSecondUpdateTicked));
+            this.UpdateTicking = ManageEventOf<UpdateTickingEventArgs>(nameof(IModEvents.GameLoop), nameof(IGameLoopEvents.UpdateTicking), isPerformanceCritical: true);
+            this.UpdateTicked = ManageEventOf<UpdateTickedEventArgs>(nameof(IModEvents.GameLoop), nameof(IGameLoopEvents.UpdateTicked), isPerformanceCritical: true);
+            this.OneSecondUpdateTicking = ManageEventOf<OneSecondUpdateTickingEventArgs>(nameof(IModEvents.GameLoop), nameof(IGameLoopEvents.OneSecondUpdateTicking), isPerformanceCritical: true);
+            this.OneSecondUpdateTicked = ManageEventOf<OneSecondUpdateTickedEventArgs>(nameof(IModEvents.GameLoop), nameof(IGameLoopEvents.OneSecondUpdateTicked), isPerformanceCritical: true);
             this.SaveCreating = ManageEventOf<SaveCreatingEventArgs>(nameof(IModEvents.GameLoop), nameof(IGameLoopEvents.SaveCreating));
             this.SaveCreated = ManageEventOf<SaveCreatedEventArgs>(nameof(IModEvents.GameLoop), nameof(IGameLoopEvents.SaveCreated));
             this.Saving = ManageEventOf<SavingEventArgs>(nameof(IModEvents.GameLoop), nameof(IGameLoopEvents.Saving));
@@ -207,7 +214,7 @@ namespace StardewModdingAPI.Framework.Events
 
             this.ButtonPressed = ManageEventOf<ButtonPressedEventArgs>(nameof(IModEvents.Input), nameof(IInputEvents.ButtonPressed));
             this.ButtonReleased = ManageEventOf<ButtonReleasedEventArgs>(nameof(IModEvents.Input), nameof(IInputEvents.ButtonReleased));
-            this.CursorMoved = ManageEventOf<CursorMovedEventArgs>(nameof(IModEvents.Input), nameof(IInputEvents.CursorMoved));
+            this.CursorMoved = ManageEventOf<CursorMovedEventArgs>(nameof(IModEvents.Input), nameof(IInputEvents.CursorMoved), isPerformanceCritical: true);
             this.MouseWheelScrolled = ManageEventOf<MouseWheelScrolledEventArgs>(nameof(IModEvents.Input), nameof(IInputEvents.MouseWheelScrolled));
 
             this.PeerContextReceived = ManageEventOf<PeerContextReceivedEventArgs>(nameof(IModEvents.Multiplayer), nameof(IMultiplayerEvents.PeerContextReceived));
@@ -228,8 +235,15 @@ namespace StardewModdingAPI.Framework.Events
             this.TerrainFeatureListChanged = ManageEventOf<TerrainFeatureListChangedEventArgs>(nameof(IModEvents.World), nameof(IWorldEvents.TerrainFeatureListChanged));
 
             this.LoadStageChanged = ManageEventOf<LoadStageChangedEventArgs>(nameof(IModEvents.Specialized), nameof(ISpecializedEvents.LoadStageChanged));
-            this.UnvalidatedUpdateTicking = ManageEventOf<UnvalidatedUpdateTickingEventArgs>(nameof(IModEvents.Specialized), nameof(ISpecializedEvents.UnvalidatedUpdateTicking));
-            this.UnvalidatedUpdateTicked = ManageEventOf<UnvalidatedUpdateTickedEventArgs>(nameof(IModEvents.Specialized), nameof(ISpecializedEvents.UnvalidatedUpdateTicked));
+            this.UnvalidatedUpdateTicking = ManageEventOf<UnvalidatedUpdateTickingEventArgs>(nameof(IModEvents.Specialized), nameof(ISpecializedEvents.UnvalidatedUpdateTicking), isPerformanceCritical: true);
+            this.UnvalidatedUpdateTicked = ManageEventOf<UnvalidatedUpdateTickedEventArgs>(nameof(IModEvents.Specialized), nameof(ISpecializedEvents.UnvalidatedUpdateTicked), isPerformanceCritical: true);
+        }
+
+        /// <summary>Get all managed events.</summary>
+        public IEnumerable<IManagedEvent> GetAllEvents()
+        {
+            foreach (FieldInfo field in this.GetType().GetFields())
+                yield return (IManagedEvent)field.GetValue(this);
         }
     }
 }
diff --git a/src/SMAPI/Framework/Events/IManagedEvent.cs b/src/SMAPI/Framework/Events/IManagedEvent.cs
new file mode 100644
index 00000000..e4e3ca08
--- /dev/null
+++ b/src/SMAPI/Framework/Events/IManagedEvent.cs
@@ -0,0 +1,15 @@
+namespace StardewModdingAPI.Framework.Events
+{
+    /// <summary>Metadata for an event raised by SMAPI.</summary>
+    internal interface IManagedEvent
+    {
+        /*********
+        ** Accessors
+        *********/
+        /// <summary>A human-readable name for the event.</summary>
+        string EventName { get; }
+
+        /// <summary>Whether the event is typically called at least once per second.</summary>
+        bool IsPerformanceCritical { get; }
+    }
+}
diff --git a/src/SMAPI/Framework/Events/ManagedEvent.cs b/src/SMAPI/Framework/Events/ManagedEvent.cs
index 2afe7a03..118b73ac 100644
--- a/src/SMAPI/Framework/Events/ManagedEvent.cs
+++ b/src/SMAPI/Framework/Events/ManagedEvent.cs
@@ -1,12 +1,13 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using StardewModdingAPI.Framework.PerformanceMonitoring;
 
 namespace StardewModdingAPI.Framework.Events
 {
     /// <summary>An event wrapper which intercepts and logs errors in handler code.</summary>
     /// <typeparam name="TEventArgs">The event arguments type.</typeparam>
-    internal class ManagedEvent<TEventArgs>
+    internal class ManagedEvent<TEventArgs> : IManagedEvent
     {
         /*********
         ** Fields
@@ -14,9 +15,6 @@ namespace StardewModdingAPI.Framework.Events
         /// <summary>The underlying event.</summary>
         private event EventHandler<TEventArgs> Event;
 
-        /// <summary>A human-readable name for the event.</summary>
-        private readonly string EventName;
-
         /// <summary>Writes messages to the log.</summary>
         private readonly IMonitor Monitor;
 
@@ -29,6 +27,19 @@ namespace StardewModdingAPI.Framework.Events
         /// <summary>The cached invocation list.</summary>
         private EventHandler<TEventArgs>[] CachedInvocationList;
 
+        /// <summary>Tracks performance metrics.</summary>
+        private readonly PerformanceMonitor PerformanceMonitor;
+
+
+        /*********
+        ** Accessors
+        *********/
+        /// <summary>A human-readable name for the event.</summary>
+        public string EventName { get; }
+
+        /// <summary>Whether the event is typically called at least once per second.</summary>
+        public bool IsPerformanceCritical { get; }
+
 
         /*********
         ** Public methods
@@ -37,11 +48,15 @@ namespace StardewModdingAPI.Framework.Events
         /// <param name="eventName">A human-readable name for the event.</param>
         /// <param name="monitor">Writes messages to the log.</param>
         /// <param name="modRegistry">The mod registry with which to identify mods.</param>
-        public ManagedEvent(string eventName, IMonitor monitor, ModRegistry modRegistry)
+        /// <param name="performanceMonitor">Tracks performance metrics.</param>
+        /// <param name="isPerformanceCritical">Whether the event is typically called at least once per second.</param>
+        public ManagedEvent(string eventName, IMonitor monitor, ModRegistry modRegistry, PerformanceMonitor performanceMonitor, bool isPerformanceCritical = false)
         {
             this.EventName = eventName;
             this.Monitor = monitor;
             this.ModRegistry = modRegistry;
+            this.PerformanceMonitor = performanceMonitor;
+            this.IsPerformanceCritical = isPerformanceCritical;
         }
 
         /// <summary>Get whether anything is listening to the event.</summary>
@@ -81,17 +96,21 @@ namespace StardewModdingAPI.Framework.Events
             if (this.Event == null)
                 return;
 
-            foreach (EventHandler<TEventArgs> handler in this.CachedInvocationList)
+
+            this.PerformanceMonitor.Track(this.EventName, () =>
             {
-                try
+                foreach (EventHandler<TEventArgs> handler in this.CachedInvocationList)
                 {
-                    handler.Invoke(null, args);
-                }
-                catch (Exception ex)
-                {
-                    this.LogError(handler, ex);
+                    try
+                    {
+                        this.PerformanceMonitor.Track(this.EventName, this.GetModNameForPerformanceCounters(handler), () => handler.Invoke(null, args));
+                    }
+                    catch (Exception ex)
+                    {
+                        this.LogError(handler, ex);
+                    }
                 }
-            }
+            });
         }
 
         /// <summary>Raise the event and notify all handlers.</summary>
@@ -122,6 +141,19 @@ namespace StardewModdingAPI.Framework.Events
         /*********
         ** Private methods
         *********/
+        /// <summary>Get the mod name for a given event handler to display in performance monitoring reports.</summary>
+        /// <param name="handler">The event handler.</param>
+        private string GetModNameForPerformanceCounters(EventHandler<TEventArgs> handler)
+        {
+            IModMetadata mod = this.GetSourceMod(handler);
+            if (mod == null)
+                return Constants.GamePerformanceCounterName;
+
+            return mod.HasManifest()
+                ? mod.Manifest.UniqueID
+                : mod.DisplayName;
+        }
+
         /// <summary>Track an event handler.</summary>
         /// <param name="mod">The mod which added the handler.</param>
         /// <param name="handler">The event handler.</param>
diff --git a/src/SMAPI/Framework/GameVersion.cs b/src/SMAPI/Framework/GameVersion.cs
index 29cfbc39..07957624 100644
--- a/src/SMAPI/Framework/GameVersion.cs
+++ b/src/SMAPI/Framework/GameVersion.cs
@@ -3,8 +3,8 @@ using System.Collections.Generic;
 
 namespace StardewModdingAPI.Framework
 {
-    /// <summary>An implementation of <see cref="ISemanticVersion"/> that correctly handles the non-semantic versions used by older Stardew Valley releases.</summary>
-    internal class GameVersion : SemanticVersion
+    /// <summary>An extension of <see cref="ISemanticVersion"/> that correctly handles non-semantic versions used by Stardew Valley.</summary>
+    internal class GameVersion : Toolkit.SemanticVersion
     {
         /*********
         ** Private methods
@@ -18,11 +18,11 @@ namespace StardewModdingAPI.Framework
             ["1.03"] = "1.0.3",
             ["1.04"] = "1.0.4",
             ["1.05"] = "1.0.5",
-            ["1.051"] = "1.0.6-prerelease1", // not a very good mapping, but good enough for SMAPI's purposes.
-            ["1.051b"] = "1.0.6-prerelease2",
+            ["1.051"] = "1.0.5.1",
+            ["1.051b"] = "1.0.5.2",
             ["1.06"] = "1.0.6",
             ["1.07"] = "1.0.7",
-            ["1.07a"] = "1.0.8-prerelease1",
+            ["1.07a"] = "1.0.7.1",
             ["1.08"] = "1.0.8",
             ["1.1"] = "1.1.0",
             ["1.2"] = "1.2.0",
@@ -36,7 +36,7 @@ namespace StardewModdingAPI.Framework
         /// <summary>Construct an instance.</summary>
         /// <param name="version">The game version string.</param>
         public GameVersion(string version)
-            : base(GameVersion.GetSemanticVersionString(version)) { }
+            : base(GameVersion.GetSemanticVersionString(version), allowNonStandard: true) { }
 
         /// <summary>Get a string representation of the version.</summary>
         public override string ToString()
@@ -53,33 +53,21 @@ namespace StardewModdingAPI.Framework
         private static string GetSemanticVersionString(string gameVersion)
         {
             // mapped version
-            if (GameVersion.VersionMap.TryGetValue(gameVersion, out string semanticVersion))
-                return semanticVersion;
-
-            // special case: four-part versions
-            string[] parts = gameVersion.Split('.');
-            if (parts.Length == 4)
-                return $"{parts[0]}.{parts[1]}.{parts[2]}+{parts[3]}";
-
-            return gameVersion;
+            return GameVersion.VersionMap.TryGetValue(gameVersion, out string semanticVers