4 files changed, 57 insertions, 5 deletions

diff --git a/src/crepe/Component.h b/src/crepe/Component.h
index 12c10cb..7734335 100644
--- a/src/crepe/Component.h
+++ b/src/crepe/Component.h
@@ -16,7 +16,12 @@ class Component {
 public:
 	//! Whether the component is active
 	bool active = true;
-	//! The id of the GameObject this component belongs to
+	/**
+	 * \brief The id of the GameObject this component belongs to
+	 *
+	 * \note Only systems are supposed to use this member, but since friend
+	 * relations aren't inherited this needs to be public.
+	 */
 	const game_object_id_t game_object_id;
 
 protected:
@@ -24,10 +29,9 @@ protected:
 	 * \param id The id of the GameObject this component belongs to
 	 */
 	Component(game_object_id_t id);
-	//! Only the ComponentManager can create components
+	//! Only ComponentManager can create components
 	friend class ComponentManager;
 
-public:
 	/**
 	 * \brief Get the maximum number of instances for this component
 	 *
@@ -38,6 +42,8 @@ public:
 	 * \return The maximum number of instances for this component
 	 */
 	virtual int get_instances_max() const { return -1; }
+	//! Only ComponentManager needs to know the max instance count
+	friend class ComponentManager;
 };
 
 } // namespace crepe
diff --git a/src/crepe/api/AudioSource.h b/src/crepe/api/AudioSource.h
index 8a78927..1264790 100644
--- a/src/crepe/api/AudioSource.h
+++ b/src/crepe/api/AudioSource.h
@@ -7,10 +7,19 @@
 
 namespace crepe {
 
+class AudioSystem;
+
 //! Audio source component
 class AudioSource : public Component {
-public:
+	//! AudioSource components are handled by AudioSystem
+	friend class AudioSystem;
+
+protected:
 	AudioSource(game_object_id_t id, const Asset & source);
+	//! Only ComponentManager can create components
+	friend class ComponentManager;
+public:
+	// But std::unique_ptr needs to be able to destoy this component again
 	virtual ~AudioSource() = default;
 
 public:
diff --git a/src/crepe/system/AudioSystem.cpp b/src/crepe/system/AudioSystem.cpp
index 67967ef..c8dae9d 100644
--- a/src/crepe/system/AudioSystem.cpp
+++ b/src/crepe/system/AudioSystem.cpp
@@ -14,7 +14,42 @@ void AudioSystem::update() {
 		AudioSource & component = component_ref.get();
 		if (!component.active) continue;
 
-		// TODO: fetch Sound instance from resourcemanager
+		/**
+		 * How this is supposed to work:
+		 * - Get an instance of Sound for this resource/component combo (Sound
+		 *   instance is supposed to be unique per component, even if they use the
+		 *   same underlying asset).
+		 * OR
+		 * - Use the same instance of Sound if this is what the cache returns
+		 *   (= what the game programmer's wishes to do).
+		 *
+		 * NOT supposed to happen but still the case:
+		 * - Below function call causes assets to be cached unintentionally
+		 * - Cached assets are deleted at the end of a scene (i think?)
+		 * - I'm not sure if the ResourceManager is even supposed to have a public
+		 *   `.clear()` method since the control over resource lifetime is
+		 *   explicitly handed over to the game programmer by using ResourceManager
+		 *   to cache/uncache. I believe the proper methods are supposed to be:
+		 *
+		 *   - get()       get a reference to resource (used here)
+		 *   - clear()     clears NON-cached assets
+		 *   - cache()     marks asset as "do not delete at end of scene"
+		 *   - uncache()   undoes the above
+		 *
+		 *   I think somewhere in the above function calls a unique identifier for
+		 *   the Asset/GameObject should be given to make sure the unique instance
+		 *   shit works as intended. The resource manager is also used for things
+		 *   other than sounds.
+		 *
+		 * Also need to check:
+		 * - Is it an issue if there are multiple AudioSource components playing
+		 *   the same sample (= identical Asset), while they are all triggered
+		 *   using the same underlying instance of Sound (esp. w/
+		 *   play/pause/retrigger behavior).
+		 */
+		Sound & sound = this->resman.cache<Sound>(component.source);
+		sound.set_context(this->context);
+
 		// TODO: lots of state diffing
 	}
 }
diff --git a/src/crepe/system/AudioSystem.h b/src/crepe/system/AudioSystem.h
index e037f51..d0b4f9a 100644
--- a/src/crepe/system/AudioSystem.h
+++ b/src/crepe/system/AudioSystem.h
@@ -1,6 +1,7 @@
 #pragma once
 
 #include "../facade/SoundContext.h"
+#include "../api/ResourceManager.h"
 
 #include "System.h"
 
@@ -13,6 +14,7 @@ public:
 
 private:
 	SoundContext context {};
+	ResourceManager & resman = ResourceManager::get_instance();
 };
 
 } // namespace crepe