1 files changed, 87 insertions, 0 deletions
diff --git a/src/StardewModdingAPI/Events/ContentEvents.cs b/src/StardewModdingAPI/Events/ContentEvents.cs
new file mode 100644
index 00000000..9418673a
--- /dev/null
+++ b/src/StardewModdingAPI/Events/ContentEvents.cs
@@ -0,0 +1,87 @@
+using System;
+using System.Collections.Generic;
+using StardewModdingAPI.Framework;
+
+namespace StardewModdingAPI.Events
+{
+    /// <summary>Events raised when the game loads content.</summary>
+    [Obsolete("This is an undocumented experimental API and may change without warning.")]
+    public static class ContentEvents
+    {
+        /*********
+        ** Properties
+        *********/
+        /// <summary>Tracks the installed mods.</summary>
+        private static ModRegistry ModRegistry;
+
+        /// <summary>Encapsulates monitoring and logging.</summary>
+        private static IMonitor Monitor;
+
+        /// <summary>The mods using the experimental API for which a warning has been raised.</summary>
+        private static readonly HashSet<string> WarnedMods = new HashSet<string>();
+
+
+        /*********
+        ** Events
+        *********/
+        /// <summary>Raised after the content language changes.</summary>
+        public static event EventHandler<EventArgsValueChanged<string>> AfterLocaleChanged;
+
+        /// <summary>Raised when an XNB file is being read into the cache. Mods can change the data here before it's cached.</summary>
+        internal static event EventHandler<IContentEventHelper> AfterAssetLoaded;
+
+
+        /*********
+        ** Internal methods
+        *********/
+        /// <summary>Injects types required for backwards compatibility.</summary>
+        /// <param name="modRegistry">Tracks the installed mods.</param>
+        /// <param name="monitor">Encapsulates monitoring and logging.</param>
+        internal static void Shim(ModRegistry modRegistry, IMonitor monitor)
+        {
+            ContentEvents.ModRegistry = modRegistry;
+            ContentEvents.Monitor = monitor;
+        }
+
+        /// <summary>Raise an <see cref="AfterLocaleChanged"/> event.</summary>
+        /// <param name="monitor">Encapsulates monitoring and logging.</param>
+        /// <param name="oldLocale">The previous locale.</param>
+        /// <param name="newLocale">The current locale.</param>
+        internal static void InvokeAfterLocaleChanged(IMonitor monitor, string oldLocale, string newLocale)
+        {
+            monitor.SafelyRaiseGenericEvent($"{nameof(ContentEvents)}.{nameof(ContentEvents.AfterLocaleChanged)}", ContentEvents.AfterLocaleChanged?.GetInvocationList(), null, new EventArgsValueChanged<string>(oldLocale, newLocale));
+        }
+
+        /// <summary>Raise an <see cref="AfterAssetLoaded"/> event.</summary>
+        /// <param name="monitor">Encapsulates monitoring and logging.</param>
+        /// <param name="contentHelper">Encapsulates access and changes to content being read from a data file.</param>
+        internal static void InvokeAfterAssetLoaded(IMonitor monitor, IContentEventHelper contentHelper)
+        {
+            if (ContentEvents.AfterAssetLoaded != null)
+            {
+                Delegate[] handlers = ContentEvents.AfterAssetLoaded.GetInvocationList();
+                ContentEvents.RaiseDeprecationWarning(handlers);
+                monitor.SafelyRaiseGenericEvent($"{nameof(ContentEvents)}.{nameof(ContentEvents.AfterAssetLoaded)}", handlers, null, contentHelper);
+            }
+        }
+
+
+        /*********
+        ** Private methods
+        *********/
+        /// <summary>Raise a 'experimental API' warning for each mod using the content API.</summary>
+        /// <param name="handlers">The event handlers.</param>
+        private static void RaiseDeprecationWarning(Delegate[] handlers)
+        {
+            foreach (Delegate handler in handlers)
+            {
+                string modName = ContentEvents.ModRegistry.GetModFrom(handler) ?? "An unknown mod";
+                if (!ContentEvents.WarnedMods.Contains(modName))
+                {
+                    ContentEvents.WarnedMods.Add(modName);
+                    ContentEvents.Monitor.Log($"{modName} used the undocumented and experimental content API, which may change or be removed without warning.", LogLevel.Warn);
+                }
+            }
+        }
+    }
+}