/**
	roflcat
	Copyright (C) 2019 rexy712

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef PRINTER_BASE_HPP
#define PRINTER_BASE_HPP

#include "cmd.hpp"
#include <type_traits> //std::is_same
#include <utility> //std::declval

#define SHOW_TABS_STRING L"^I"
#define LINE_NUMBERING_SPACE STRINGIFY(8)

#define REAL_STRINGIFY(x) #x
#define STRINGIFY(x) REAL_STRINGIFY(x)


//name of struct generated by OPTIONAL_MEMBER_FUNC for given x
#define HAS_FUNC(x) _determine_has_member_func_##x
//generate utility struct to determine if a given class has a member function
#define OPTIONAL_MEMBER_FUNC(x) \
template<class U, class Ret = void, class... Args> \
struct HAS_FUNC(x){ \
private: \
	template<class T, Ret& (T::*)(Args...)> \
	struct check_s{}; \
	template<class T> \
	static char test(check_s<T, &T::x>*); \
	template<class T> \
	static int test(...); \
public: \
	static constexpr bool value = std::is_same<char,decltype(test<U>(nullptr))>::value; \
}


//Defines an interface for the base classes
//require a _print and an optional _reset function
template<class Derived>
class printer_base
{
private:
	OPTIONAL_MEMBER_FUNC(_reset);

private:
	const bool m_show_ends = false;
	const int m_print_ln = PRINT_LINE_NEVER;
	const bool m_squeeze_blank = false;
	int m_squeeze_cnt = 0;
	bool m_newline = true;
	int m_line_num = 1;
	const wchar_t* const m_tab_str = L"\t";
	const size_t m_tab_size = 1;

protected:
	constexpr printer_base(void)noexcept = default;
	constexpr printer_base(const wchar_t* tabstr, const cmd_args& args)noexcept;
	~printer_base(void)noexcept = default;
public:
	constexpr Derived& print(wchar_t s)noexcept(noexcept(std::declval<Derived>()._print(s)));
	constexpr Derived& print(const wchar_t* s)noexcept(noexcept(std::declval<printer_base<Derived>>().print(std::declval<wchar_t>())));
	constexpr Derived& print(char s);
	constexpr Derived& print(const char* s);
	constexpr Derived& reset(void);
};

#endif