GServer-v2/server/include/Scripting/interface/ScriptArguments.h

#pragma once

#ifndef SCRIPTARGUMENTS_H
#define SCRIPTARGUMENTS_H

#include <memory>
#include <string>
#include <tuple>
#include "ScriptObject.h"

class IScriptFunction;

namespace detail
{
	template<typename T>
	inline void InvalidateBinding(T val) {
	}

	template<typename T>
	inline void InvalidateBinding(IScriptObject<T>* val) {
		// Decrease reference for wrapped objects
		val->decreaseReference();
	}

	template<typename T>
	inline void ValidateBinding(T val) {
	}

	template<typename T>
	inline void ValidateBinding(IScriptObject<T>* val) {
		// Increase reference for wrapped objects
		val->increaseReference();
	}
};

class IScriptArguments
{
public:
	IScriptArguments() = default;
	virtual ~IScriptArguments() = default;
	
	virtual bool Invoke(IScriptFunction *func, bool catchExceptions = false) = 0;
};

template <typename... Ts>
class ScriptArguments : public IScriptArguments
{
public:
	template <typename... Args>
	ScriptArguments(Args&&... An)
		: IScriptArguments(), _resolved(false), _tuple(std::forward<Args>(An)...) {
		validate_args(std::index_sequence_for<Ts...>{});
	}
	
	virtual ~ScriptArguments() {
		if (!_resolved) {
			invalidate_args(std::index_sequence_for<Ts...>{});
		}
	}

	virtual bool Invoke(IScriptFunction *func, bool catchExceptions = false) = 0;

	inline size_t Count() const {
		return Argc;
	}

	inline const std::tuple<Ts...> & Args() const {
		return _tuple;
	}

protected:
	static constexpr int Argc = (sizeof...(Ts));

	bool _resolved;
	std::tuple<Ts...> _tuple;

private:
	template <std::size_t...Is>
	inline void invalidate_args(std::index_sequence<Is...>) {
		if constexpr (sizeof...(Is) > 0) {
			int unused[] = { ((detail::InvalidateBinding(std::get<Is>(_tuple))), void(), 0)... };
			static_cast<void>(unused); // Avoid warning for unused variable
		}
	}

	template <std::size_t...Is>
	inline void validate_args(std::index_sequence<Is...>) {
		if constexpr (sizeof...(Is) > 0) {
			int unused[] = { ((detail::ValidateBinding(std::get<Is>(_tuple))), void(), 0)... };
			static_cast<void>(unused); // Avoid warning for unused variable
		}
	}
};

#endif