/*
	This file is part of Fennix Kernel.

	Fennix Kernel 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.

	Fennix Kernel 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 Fennix Kernel. If not, see <https://www.gnu.org/licenses/>.
*/

#pragma once

#include <system_error>
#include <string>
#include <vector>
#include <locale>

#ifdef in
#undef in
#endif /* deprecated macro in */

namespace std
{
	enum class io_errc
	{
		stream = 1,
	};

	typedef long long streamsize;

	class ios_base
	{
	public:
#pragma region Member types and constants

		typedef int openmode;
		static constexpr openmode app = 1;
		static constexpr openmode binary = 2;
		static constexpr openmode in = 4;
		static constexpr openmode out = 8;
		static constexpr openmode trunc = 16;
		static constexpr openmode ate = 32;
		static constexpr openmode noreplace = 64;

		typedef int fmtflags;
		static constexpr fmtflags dec = 1;
		static constexpr fmtflags oct = 2;
		static constexpr fmtflags hex = 4;
		static constexpr fmtflags basefield = dec | oct | hex;

		static constexpr fmtflags left = 1;
		static constexpr fmtflags right = 2;
		static constexpr fmtflags internal = 4;
		static constexpr fmtflags adjustfield = left | right | internal;

		static constexpr fmtflags scientific = 1;
		static constexpr fmtflags fixed = 2;
		static constexpr fmtflags floatfield = scientific | fixed;

		static constexpr fmtflags boolalpha = 1;
		static constexpr fmtflags showbase = 2;
		static constexpr fmtflags showpoint = 4;
		static constexpr fmtflags showpos = 8;
		static constexpr fmtflags skipws = 16;
		static constexpr fmtflags unitbuf = 32;
		static constexpr fmtflags uppercase = 64;

		typedef int iostate;
		static constexpr iostate goodbit = 0;
		static constexpr iostate badbit = 1;
		static constexpr iostate failbit = 2;
		static constexpr iostate eofbit = 4;

		typedef int seekdir;
		static constexpr seekdir beg = 0;
		static constexpr seekdir end = 1;
		static constexpr seekdir cur = 2;

		enum event
		{
			erase_event,
			imbue_event,
			copyfmt_event
		};

		typedef void (*event_callback)(event type, ios_base &ios, int index);

#pragma endregion Member types and constants

#pragma region Constructors

	protected:
		ios_base();

	public:
		ios_base(const ios_base &) = delete;
		virtual ~ios_base() = default;
		ios_base &operator=(const ios_base &) = delete;

#pragma endregion Constructors

#pragma region Formatting

		fmtflags flags() const
		{
			return _flags;
		}

		fmtflags flags(fmtflags flags)
		{
			fmtflags old = _flags;
			_flags = flags;
			return old;
		}

		fmtflags setf(fmtflags flags)
		{
			fmtflags old = _flags;
			_flags |= flags;
			return old;
		}

		fmtflags setf(fmtflags flags, fmtflags mask)
		{
			fmtflags old = _flags;
			_flags &= ~mask;
			_flags |= flags;
			return old;
		}

		void unsetf(fmtflags flags)
		{
			_flags &= ~flags;
		}

		streamsize precision() const
		{
			return _precision;
		}

		streamsize precision(streamsize new_precision)
		{
			streamsize old = _precision;
			_precision = new_precision;
			return old;
		}

		streamsize width() const
		{
			return _width;
		}

		streamsize width(streamsize new_width)
		{
			streamsize old = _width;
			_width = new_width;
			return old;
		}

#pragma endregion Formatting

#pragma region Locales

		std::locale imbue(const std::locale &loc)
		{
			std::locale old = _loc;
			_loc = loc;
			__call_event(imbue_event, *this, 0);
			return old;
		}

		std::locale getloc() const
		{
			return _loc;
		}

#pragma endregion Locales

#pragma region Internal Extensible Array

		static int xalloc()
		{
			static int index = 0;
			return index++;
		}

		long &iword(int index)
		{
			static std::vector<long> iwords;
			if ((size_t)index >= iwords.size())
				iwords.resize(index + 1);
			return iwords[index];
		}

		void *&pword(int index)
		{
			static std::vector<void *> pwords;
			if ((size_t)index >= pwords.size())
				pwords.resize(index + 1);
			return pwords[index];
		}

#pragma endregion Internal Extensible Array

#pragma region Miscellaneous

		void register_callback(event_callback function, int index)
		{
			_event_callback = function;
			__call_event(imbue_event, *this, index);
		}

		static bool sync_with_stdio(bool sync = true)
		{
			return false;
		}

#pragma endregion Miscellaneous

#pragma region Member Classes

		class failure
		{
		public:
			explicit failure(const std::string &message, const std::error_code &ec = std::io_errc::stream)
			{
			}

			explicit failure(const char *message, const std::error_code &ec = std::io_errc::stream)
			{
			}

			failure(const failure &other) noexcept
			{
			}

			failure &operator=(const failure &other) noexcept
			{
				return *this;
			}

			virtual const char *what() const noexcept
			{
				return nullptr;
			}
		};

		class Init
		{
		public:
			Init() = default;
			~Init() = default;
		};

#pragma endregion Member Classes

	private:
		fmtflags _flags = skipws;
		streamsize _precision = 6;
		streamsize _width = 0;
		std::locale _loc = std::locale::classic();

		static event_callback _event_callback;

		static void __call_event(event type, ios_base &ios, int index)
		{
			if (_event_callback)
				_event_callback(type, ios, index);
		}
	};

	template <class CharT, class Traits = std::char_traits<CharT>>
	class basic_ios : public std::ios_base
	{
	};

	typedef basic_ios<char> ios;
	typedef basic_ios<wchar_t> wios;
}
