PR Verification BepInEx

S1API/AssetBundles/AssetLoader.cs

@@ -0,0 +1,132 @@
+using System;
+using System.Collections.Generic;
+using System.Reflection;
+
+#if IL2CPPBEPINEX || IL2CPPMELON
+using System.IO;
+#endif
+
+using UnityEngine;
+using Object = UnityEngine.Object;
+
+using S1API.Logging;
+
+namespace S1API.AssetBundles
+{
+    /// <summary>
+    /// The asset bundle manager
+    /// </summary>
+    public static class AssetLoader
+    {
+        private static readonly Log _logger = new Log("AssetLoader");
+        private static readonly Dictionary<string, WrappedAssetBundle> _cachedAssetBundles = new Dictionary<string, WrappedAssetBundle>();
+
+#if IL2CPPMELON || IL2CPPBEPINEX
+        /// <summary>
+        /// Loads an Il2Cpp AssetBundle from an embedded resource stream by name.
+        /// </summary>
+        /// <param name="fullResourceName">The full embedded resource name (including namespace path).</param>
+        /// <param name="overrideAssembly">The assembly to load the embedded resource from.</param>
+        /// <returns>The loaded Il2CppAssetBundle, or throws on failure.</returns>
+        public static WrappedAssetBundle GetAssetBundleFromStream(string fullResourceName, Assembly overrideAssembly)
+        {
+            if (_cachedAssetBundles.TryGetValue(fullResourceName, out WrappedAssetBundle cachedWrappedAssetBundle))
+                return cachedWrappedAssetBundle;
+
+            // Attempt to find the embedded resource in the executing assembly
+            using Stream? stream = overrideAssembly.GetManifestResourceStream(fullResourceName);
+            if (stream == null)
+                throw new Exception($"Embedded resource '{fullResourceName}' not found in {overrideAssembly.FullName}."); // hoping these throws will be melon/bepinex-agnostic
+
+            // Read the stream into a byte array
+            byte[] data = new byte[stream.Length];
+            _ = stream.Read(data, 0, data.Length);
+
+            // Load the AssetBundle from memory
+            Il2CppAssetBundle bundle = Il2CppAssetBundleManager.LoadFromMemory(data);
+            if (bundle == null)
+                throw new Exception($"Failed to load AssetBundle from memory: {fullResourceName}");
+
+            WrappedAssetBundle wrappedAssetBundle = new WrappedAssetBundle(bundle);
+            _cachedAssetBundles.TryAdd(fullResourceName, wrappedAssetBundle);
+            return wrappedAssetBundle;
+        }
+#elif MONOMELON || MONOBEPINEX
+        /// <summary>
+        /// Load a <see cref="WrappedAssetBundle"/> instance by <see cref="string"/> resource name.
+        /// </summary>
+        /// <param name="fullResourceName">The full embedded resource name (including namespace path);</param>
+        /// <param name="overrideAssembly">The assembly to load the embedded resource from.</param>
+        /// <returns>The loaded AssetBundle instance</returns>
+        public static WrappedAssetBundle GetAssetBundleFromStream(string fullResourceName, Assembly overrideAssembly)
+        {
+            // Attempt to retrieve the cached asset bundle
+            if (_cachedAssetBundles.TryGetValue(fullResourceName, out WrappedAssetBundle cachedWrappedAssetBundle))
+                return cachedWrappedAssetBundle;
+
+            // Attempt to find the embedded resource in the executing assembly
+            var stream = overrideAssembly.GetManifestResourceStream(fullResourceName);
+
+            WrappedAssetBundle wrappedAssetBundle = new WrappedAssetBundle(AssetBundle.LoadFromStream(stream));
+            _cachedAssetBundles.TryAdd(fullResourceName, wrappedAssetBundle);
+            return wrappedAssetBundle;
+        }
+#endif
+
+        /// <summary>
+        /// Loads an asset of type <typeparamref name="T"/> from an embedded AssetBundle using the executing assembly.
+        /// </summary>
+        /// <typeparam name="T">The type of asset to load (must derive from UnityEngine.Object).</typeparam>
+        /// <param name="bundleName">The name of the embedded AssetBundle resource.</param>
+        /// <param name="objectName">The name of the asset to load within the AssetBundle.</param>
+        /// <returns>The loaded asset of type <typeparamref name="T"/>.</returns>
+        public static T EasyLoad<T>(string bundleName, string objectName) where T : Object
+        {
+            return EasyLoad<T>(bundleName, objectName, Assembly.GetExecutingAssembly(), out _);
+        }
+
+        /// <summary>
+        /// Loads an asset of type <typeparamref name="T"/> from an embedded AssetBundle using the executing assembly and outputs the loaded bundle.
+        /// </summary>
+        /// <typeparam name="T">The type of asset to load (must derive from UnityEngine.Object).</typeparam>
+        /// <param name="bundleName">The name of the embedded AssetBundle resource.</param>
+        /// <param name="objectName">The name of the asset to load within the AssetBundle.</param>
+        /// <param name="bundle">The output parameter containing the loaded <see cref="WrappedAssetBundle"/>.</param>
+        /// <returns>The loaded asset of type <typeparamref name="T"/>.</returns>
+        public static T EasyLoad<T>(string bundleName, string objectName, out WrappedAssetBundle bundle) where T : Object
+        {
+            return EasyLoad<T>(bundleName, objectName, Assembly.GetExecutingAssembly(), out bundle);
+        }
+
+        /// <summary>
+        /// Loads an asset of type <typeparamref name="T"/> from an embedded AssetBundle using a specified assembly.
+        /// </summary>
+        /// <typeparam name="T">The type of asset to load (must derive from UnityEngine.Object).</typeparam>
+        /// <param name="bundleName">The name of the embedded AssetBundle resource.</param>
+        /// <param name="objectName">The name of the asset to load within the AssetBundle.</param>
+        /// <param name="assemblyOverride">The assembly from which to load the embedded AssetBundle resource.</param>
+        /// <returns>The loaded asset of type <typeparamref name="T"/>.</returns>
+        public static T EasyLoad<T>(string bundleName, string objectName, Assembly assemblyOverride) where T : Object
+        {
+            return EasyLoad<T>(bundleName, objectName, assemblyOverride, out _);
+        }
+
+        /// <summary>
+        /// Loads an asset of type <typeparamref name="T"/> from an embedded AssetBundle using a specified assembly and outputs the loaded bundle.
+        /// </summary>
+        /// <typeparam name="T">The type of asset to load (must derive from UnityEngine.Object).</typeparam>
+        /// <param name="bundleName">The name of the embedded AssetBundle resource.</param>
+        /// <param name="objectName">The name of the asset to load within the AssetBundle.</param>
+        /// <param name="assemblyOverride">The assembly from which to load the embedded AssetBundle resource.</param>
+        /// <param name="bundle">The output parameter containing the loaded <see cref="WrappedAssetBundle"/>.</param>
+        /// <returns>The loaded asset of type <typeparamref name="T"/>.</returns>
+        public static T EasyLoad<T>(string bundleName, string objectName, Assembly assemblyOverride, out WrappedAssetBundle bundle) where T : Object
+        {
+            // Get the asset bundle from the assembly
+            bundle = GetAssetBundleFromStream($"{assemblyOverride.GetName().Name}.{bundleName}", assemblyOverride);
+
+            // Load the asset from the bundle
+            return bundle.LoadAsset<T>(objectName);
+        }
+    }
+}