GameState

#pragma once

#include <vector>

class GameState{
	struct Function{
		bool isLua;
		union{
			// returns void and has no arguments
			void (*function_pointer)(); 
			char* lua_function;
		};
		Function(){
			function_pointer = nullptr;
			lua_function = nullptr; 
		}
	};

	Function m_update;
	Function m_render;
	Function m_initialize;
	Function m_return;
	Function m_cleanup;

public:
	bool active;
	// A function called 
	// when the stack is being updated
	void setUpdate();

	// A function called when
	// when the stack is being rendered
	void setRender();
	// A function called when
	// the state is first created
	void setInitialize();

	// A Function called when 
	// set to the top of the stack
	void setReturn();

	// A function called 
	// when removed from the stack
	void setCleanup();

};
 
class StateStack{ 
	std::vector<GameState> m_stack;  

public:

	// The bool if true will stop the state below (originally on top) it in the stack from updating
	// if false then it will also recieve updates.
	// This allows us to not render the menu when we push on our game state,
	// but all us to push ontop of that game state a GUI without stopping the game state.
	void push(GameState, bool);

	// The stack that is poped will have it's cleanup function called
	// if one has been defined.
	void pop();

	// executes the stack, starting at the base
	void execute();
};