/*
	Copyright 2006-2026 The QElectroTech Team
	This file is part of QElectroTech.

	QElectroTech 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 2 of the License, or
	(at your option) any later version.

	QElectroTech 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 QElectroTech.  If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef CONTACTUSAGE_H
#define CONTACTUSAGE_H

#include <algorithm>

/**
	@brief The ContactUsage struct
	How many slave contacts a master element currently uses, broken down
	by contact type.

	Header-only and free of any graphics dependency so that the counting
	rules can be unit tested on their own. MasterElement::contactUsage()
	is the thin wrapper that feeds it the linked elements.

	This counts contacts, which is what tells you how many contacts an
	auxiliary block must provide. It is deliberately not the count that
	MasterElement::isFull() uses: a master's max_slaves is a number of
	slots, and a slave fills exactly one slot however many contacts it
	carries.

	Two rules are easy to get wrong, and both live here so that every
	caller gets them right:
	 - a slave stands for as many contacts as its "number" kind
	   information says, so a 4 pole contact counts as 4, not as 1
	 - a changeover contact is counted once, as sw. CrossRefItem's
	   NOElements() and NCElements() both return it, so adding those two
	   lists together would count it twice.
*/
struct ContactUsage
{
	/**
		Contact types a slave can declare. Mirrors
		ElementData::SlaveState, which is not used directly so that this
		header stays free of the element data dependencies and can be
		unit tested on its own. MasterElement::contactUsage() maps
		between the two.
	*/
	enum Type
	{
		NO,		///< Normally open
		NC,		///< Normally closed
		SW,		///< Changeover
		Other	///< Neither of the above
	};

	int no    = 0;	///< Normally open
	int nc    = 0;	///< Normally closed
	int sw    = 0;	///< Changeover
	int other = 0;	///< Neither of the above

	int total() const { return no + nc + sw + other; }

	/**
		Add one slave element to the tally.
		@param type     the contact type the slave declares
		@param contacts how many contacts it stands for. Values below 1
		                are treated as 1: an element which declares no
		                contact count is still one contact.
	*/
	void addSlave(Type type, int contacts)
	{
		const int n = std::max(1, contacts);

		switch (type)
		{
			case NO:    no    += n; break;
			case NC:    nc    += n; break;
			case SW:    sw    += n; break;
			case Other: other += n; break;
		}
	}
};

#endif // CONTACTUSAGE_H