/*! \file piunits_base.h
 * \ingroup Core
 * \~\brief
 * \~english Unit conversions
 * \~russian Преобразование единиц измерения
 */
/*
    PIP - Platform Independent Primitives
    Unit conversions
    Ivan Pelipenko peri4ko@yandex.ru

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Lesser 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 Lesser General Public License for more details.

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

#ifndef PIUNITS_BASE_H
#define PIUNITS_BASE_H

#include "pitranslator.h"

#define DECLARE_UNIT_CLASS_BEGIN(Name, StartIndex)                              \
	namespace PIUnits {                                                         \
	namespace Class {                                                           \
	class PIP_EXPORT Name                                                       \
		: public Internal::ClassBase                                            \
		, public Internal::Registrator<Name> {                                  \
	private:                                                                    \
		friend class Internal::Registrator<Name>;                               \
		constexpr static int typeStart = StartIndex;                            \
		PIString name(int type) const override;                                 \
		PIString unit(int type) const override;                                 \
		PIString valueToString(double v, char format, int prec) const override; \
		double convert(double v, int from, int to) const override;              \
		bool supportPrefixes(int type) const override;                          \
		bool supportPrefixesNon3(int type) const override;                      \
		bool supportPrefixesGreater(int type) const override;                   \
		bool supportPrefixesSmaller(int type) const override;                   \
																				\
	public:                                                                     \
		PIString className() const override {                                   \
			return piTr(#Name, "PIUnits");                                      \
		}                                                                       \
		uint classID() const override {                                         \
			static uint ret = PIStringAscii(#Name).hash();                      \
			return ret;                                                         \
		}


#define DECLARE_UNIT_CLASS_END(Name)          \
	}                                         \
	;                                         \
	}                                         \
	}                                         \
	STATIC_INITIALIZER_BEGIN                  \
		PIUnits::Class::Name::registerSelf(); \
	STATIC_INITIALIZER_END

namespace PIUnits {

PIP_EXPORT PIString className(int type);
PIP_EXPORT PIString name(int type);
PIP_EXPORT PIString unit(int type);

namespace Class {

enum {
	Invalid = -1
};

class PIP_EXPORT Internal {
public:
	class PIP_EXPORT ClassBase {
	public:
		virtual uint classID() const                                                    = 0;
		virtual PIString className() const                                              = 0;
		virtual PIString name(int type) const                                           = 0;
		virtual PIString unit(int type) const                                           = 0;
		virtual PIString valueToString(double v, char format = 'g', int prec = 5) const = 0;
		virtual double convert(double v, int from, int to) const                        = 0;
		virtual bool supportPrefixes(int type) const { return true; }
		virtual bool supportPrefixesNon3(int type) const { return false; }
		virtual bool supportPrefixesGreater(int type) const { return true; }
		virtual bool supportPrefixesSmaller(int type) const { return true; }
		const PIVector<int> & allTypes() const { return types; }

	protected:
		PIVector<int> types;
	};
	template<typename P>
	class Registrator {
	public:
		static void registerSelf() {
			auto * uc = new P();
			for (int t = P::typeStart; t < P::_LastType; ++t) {
				uc->types << t;
				Internal::typeClasses[t] = uc;
			}
			if (!Internal::allTypeClasses.contains(uc)) Internal::allTypeClasses << uc;
		}
	};
	static PIMap<int, ClassBase *> typeClasses;
	static PIVector<ClassBase *> allTypeClasses;
	static const PIString unknown;
};


} // namespace Class

PIP_EXPORT PIVector<Class::Internal::ClassBase *> allClasses();

} // namespace PIUnits


#endif