feat(engine): allow getting the type of an asset

engine/include/cubos/engine/assets/assets.hpp

@@ -211,6 +211,16 @@ namespace cubos::engine
         /// @return Vector with all registered assets.
         std::vector<AnyAsset> listAll() const;
 
+        /// @brief Gets the type of an asset.
+        ///
+        /// If the asset is not loaded, its type is deduced from its bridge.
+        /// If there's also no associated bridge, aborts.
+        /// If the asset does not exist, aborts.
+        ///
+        /// @param handle Handle to check the type for.
+        /// @return Asset type.
+        std::type_index type(const AnyAsset& handle) const;
+
     private:
         /// @brief Represents a known asset - may or may not be loaded.
         struct Entry

engine/include/cubos/engine/assets/bridge.hpp

@@ -7,6 +7,8 @@
 
 #pragma once
 
+#include <typeindex>
+
 #include <cubos/engine/assets/asset.hpp>
 
 namespace cubos::engine
@@ -26,7 +28,14 @@ namespace cubos::engine
     class AssetBridge
     {
     public:
-        AssetBridge() = default;
+        /// @brief Constructs a bridge.
+        ///
+        /// @param index Type of assets loaded by the bridge.
+        explicit AssetBridge(std::type_index index)
+            : mIndex(index)
+        {
+        }
+
         virtual ~AssetBridge() = default;
 
         /// @brief Loads an asset.
@@ -46,5 +55,15 @@ namespace cubos::engine
         /// @param handle Handle of the asset being saved.
         /// @return Whether the asset was successfully saved.
         virtual bool save(const Assets& assets, const AnyAsset& handle);
+
+        /// @brief Gets the type of the assets the bridge loads.
+        /// @return Type of the asset.
+        inline std::type_index assetType() const
+        {
+            return mIndex;
+        }
+
+    private:
+        std::type_index mIndex; ///< Type of assets loaded by the bridge
     };
 } // namespace cubos::engine

engine/include/cubos/engine/assets/bridges/binary.hpp

@@ -27,7 +27,8 @@ namespace cubos::engine
         /// @brief Constructs a bridge.
         /// @param littleEndian Whether to use little endian byte order.
         BinaryBridge(bool littleEndian = true)
-            : mLittleEndian{littleEndian}
+            : FileBridge(typeid(T))
+            , mLittleEndian{littleEndian}
         {
         }
 

engine/include/cubos/engine/assets/bridges/file.hpp

@@ -21,6 +21,14 @@ namespace cubos::engine
     class FileBridge : public AssetBridge
     {
     public:
+        /// @brief Constructs a bridge.
+        ///
+        /// @param index Type of assets loaded by the bridge.
+        explicit FileBridge(std::type_index index)
+            : AssetBridge(index)
+        {
+        }
+
         bool load(Assets& assets, const AnyAsset& handle) final;
         bool save(const Assets& assets, const AnyAsset& handle) final;
 

engine/include/cubos/engine/assets/bridges/json.hpp

@@ -30,7 +30,8 @@ namespace cubos::engine
         ///
         /// @param indentation Indentation level to use when saving the JSON file.
         JSONBridge(int indentation = 4)
-            : mIndentation{indentation}
+            : FileBridge(typeid(T))
+            , mIndentation{indentation}
         {
         }
 

engine/include/cubos/engine/scene/bridge.hpp

@@ -5,6 +5,7 @@
 #pragma once
 
 #include <cubos/engine/assets/bridge.hpp>
+#include <cubos/engine/scene/scene.hpp>
 
 namespace cubos::engine
 {
@@ -45,6 +46,13 @@ namespace cubos::engine
     class SceneBridge : public AssetBridge
     {
     public:
+        /// @brief Constructs a bridge.
+        ///
+        SceneBridge()
+            : AssetBridge(typeid(Scene))
+        {
+        }
+
         bool load(Assets& assets, const AnyAsset& handle) override;
         bool save(const Assets& assets, const AnyAsset& handle) override;
     };

engine/samples/assets/bridge/main.cpp

@@ -21,6 +21,11 @@ using namespace cubos::engine;
 class TextBridge : public FileBridge
 {
 public:
+    TextBridge()
+        : FileBridge(typeid(std::string))
+    {
+    }
+
     bool loadFromFile(Assets& assets, const AnyAsset& handle, Stream& stream) override
     {
         // Dump the file's contents into a string.

engine/src/cubos/engine/assets/assets.cpp

@@ -589,6 +589,12 @@ void Assets::loader()
             assetEntry->status = Assets::Status::Unloaded;
             assetEntry->cond.notify_all();
         }
+        else
+        {
+            auto assetEntry = this->entry(task.handle);
+            CUBOS_ASSERT(assetEntry != nullptr);
+            CUBOS_ASSERT(assetEntry->type == task.bridge->assetType());
+        }
     }
 }
 
@@ -600,4 +606,18 @@ std::vector<AnyAsset> Assets::listAll() const
         out.emplace_back(entry);
     }
     return out;
+}
+
+std::type_index Assets::type(const AnyAsset& handle) const
+{
+    auto assetEntry = this->entry(handle);
+    CUBOS_ASSERT(assetEntry != nullptr, "Could not find asset's type");
+    if (assetEntry->status == Status::Loaded)
+    {
+        return assetEntry->type;
+    }
+
+    auto bridge = this->bridge(handle);
+    CUBOS_ASSERT(bridge != nullptr, "Could not find asset's type");
+    return bridge->assetType();
 }