[Tangerine] Add asset bundle loader

Tangerine/Plugin.cs

@@ -20,5 +20,6 @@ public override void Load()
         _harmony = new Harmony(MyPluginInfo.PLUGIN_GUID);
         TangerineDataManager.InitializeHarmony(_harmony);
         TangerineTextDataManager.InitializeHarmony(_harmony);
+        TangerineLoader.InitializeHarmony(_harmony);
     }
 }

Tangerine/TangerineLoader.cs

@@ -0,0 +1,96 @@
+using HarmonyLib;
+using System.Collections.Generic;
+using System.Reflection;
+
+namespace Tangerine
+{
+    public static class TangerineLoader
+    {
+        private static Harmony _harmony;
+
+        private static bool _assetsBundleManagerUnpatched = false;
+
+        // assetbundleName: id
+        private static readonly Dictionary<string, AssetbundleId> _assetBundleIds = new();
+
+        // id.hash: filePath
+        private static readonly Dictionary<string, string> _assetBundlePaths = new();
+
+        /// <summary>
+        /// Adds an Asset Bundle to the game's dictionary to allow it to be loaded from a custom path.
+        /// Asset bundles existing in the game will be overridden if a bundle with the same name is added.
+        /// </summary>
+        /// <param name="id">Id entry to add</param>
+        /// <param name="filePath">The path the file will be loaded from</param>
+        public static void AddAssetBundleId(AssetbundleId id, string filePath)
+        {
+            id.SetKeys();
+            _assetBundleIds[id.name] = id;
+            _assetBundlePaths[id.hash] = filePath;
+
+            if (_assetsBundleManagerUnpatched)
+            {
+                // Update the game's dictionary
+                AssetsBundleManager.Instance.dictBundleID[id.name] = id;
+            }
+        }
+
+        /// <param name="idDict"><c>Key: Value</c> mapping for <see cref="AssetbundleId"/></param>
+        /// <inheritdoc cref="AddAssetBundleId(AssetbundleId, string)"/>
+        public static void AddAssetBundleId(Dictionary<string, object> idDict, string filePath)
+        {
+            AddAssetBundleId(CreateAssetbundleIdFromDict(idDict), filePath);
+        }
+
+        /// <summary>
+        /// Adds a file hash to be loaded from a custom path when the game asks for the file.
+        /// This method is for adding files that are not asset bundles, like <c>.acb</c> files.
+        /// Use <see cref="AddAssetBundleId(AssetbundleId, string)"/> for adding asset bundles.
+        /// </summary>
+        /// <param name="hash">MD5 hash of the file name that the game will search for</param>
+        /// <inheritdoc cref="AddAssetBundleId(AssetbundleId, string)"/>
+        public static void AddFile(string hash, string filePath)
+        {
+            _assetBundlePaths[hash] = filePath;
+        }
+
+        internal static void InitializeHarmony(Harmony harmony)
+        {
+            _harmony = harmony;
+            _harmony.PatchAll(typeof(TangerineLoader));
+        }
+
+        private static AssetbundleId CreateAssetbundleIdFromDict(Dictionary<string, object> dict)
+        {
+            return new AssetbundleId((string)dict["name"], (string)dict["hash"], (uint)dict["crc"], (long)dict["size"]);
+        }
+
+        [HarmonyPatch(typeof(AssetsBundleManager), nameof(AssetsBundleManager.OnStartLoadSingleAsset))]
+        [HarmonyPostfix]
+        public static void AddAssetbundleIdsPatch(AssetsBundleManager __instance, MethodBase __originalMethod)
+        {
+            // This will override existing bundle ids in the manager's dict
+            foreach (var id in _assetBundleIds.Values)
+            {
+                __instance.dictBundleID[id.name] = id;
+                Plugin.Log.LogWarning($"Added AssetbundleId: [{id.hash}] {id.name}");
+            }
+
+            Plugin.Log.LogWarning($"Unpatching {nameof(AssetsBundleManager)} postfix");
+            _harmony.Unpatch(__originalMethod, MethodBase.GetCurrentMethod() as MethodInfo);
+            _assetsBundleManagerUnpatched = true;
+        }
+
+        [HarmonyPatch(typeof(AssetsBundleManager), nameof(AssetsBundleManager.GetPath))]
+        [HarmonyPostfix]
+        private static void GetPathPostfix(string file, ref string __result)
+        {
+            if (_assetBundlePaths.TryGetValue(file, out var filePath))
+            {
+                // Update file path
+                __result = filePath;
+                Plugin.Log.LogWarning($"Replaced path for file: ({__result})");
+            }
+        }
+    }
+}