add file obj comp to prep for move

we now depend on os

external/CMakeLists.txt

@@ -20,3 +20,12 @@ if (NOT TARGET solanaceae_util)
 	FetchContent_MakeAvailable(solanaceae_util)
 endif()
 
+if (NOT TARGET solanaceae_object_store)
+	FetchContent_Declare(solanaceae_object_store
+		GIT_REPOSITORY https://github.com/Green-Sky/solanaceae_object_store.git
+		GIT_TAG master
+		EXCLUDE_FROM_ALL
+	)
+	FetchContent_MakeAvailable(solanaceae_object_store)
+endif()
+

src/CMakeLists.txt

@@ -28,6 +28,7 @@ target_compile_features(solanaceae_message3 PUBLIC cxx_std_17)
 target_link_libraries(solanaceae_message3 PUBLIC
 	solanaceae_util
 	solanaceae_contact
+	solanaceae_object_store # for fwd.hpp in components
 	EnTT::EnTT
 )
 

src/solanaceae/message3/components.hpp

@@ -4,8 +4,7 @@
 
 #include "./message.hpp"
 
-//fwd
+#include <solanaceae/object_store/fwd.hpp>
-struct File2I;
 
 #include <entt/container/dense_map.hpp>
 
@@ -72,6 +71,11 @@ namespace Message::Components {
 
 	struct TagMessageIsAction {};
 
+	// points to the object providing the file for this message
+	struct MessageFileObject {
+		ObjectHandle o;
+	};
+
 	namespace Transfer {
 
 		//struct TransferState {

src/solanaceae/message3/components_id.inl

@@ -30,6 +30,7 @@ DEFINE_COMP_ID(Message::Components::ReadBy)
 DEFINE_COMP_ID(Message::Components::SyncedBy)
 DEFINE_COMP_ID(Message::Components::MessageText)
 DEFINE_COMP_ID(Message::Components::TagMessageIsAction)
+DEFINE_COMP_ID(Message::Components::MessageFileObject)
 
 DEFINE_COMP_ID(Message::Components::Transfer::TagHaveAll)
 DEFINE_COMP_ID(Message::Components::Transfer::BytesSent)