// 2010 © Václav Šmilauer <eudoxos@arcig.cz>

#include <pkg/common/MatchMaker.hpp>

namespace yade { // Cannot have #include directive inside.

YADE_PLUGIN((MatchMaker));

Real MatchMaker::operator()(int id1, int id2, Real val1, Real val2) const
{
	const int minId = std::min(id1, id2);
	const int maxId = std::max(id1, id2);

	const auto foundMatchItem = matchSet.find(std::make_pair(minId, maxId));

	if (foundMatchItem != matchSet.end()) {
		return foundMatchItem->second;
	} else {
		if (fbNeedsValues && (math::isnan(val1) || math::isnan(val2))) {
			throw std::invalid_argument(
			        "MatchMaker: no match for (" + boost::lexical_cast<string>(id1) + "," + boost::lexical_cast<string>(id2)
			        + "), and values required for algo computation '" + algo + "' not specified.");
		}
		return computeFallback(val1, val2);
	}
}

void MatchMaker::postLoad(MatchMaker&)
{
	if (algo == "val") {
		fbPtr         = &MatchMaker::fbVal;
		fbNeedsValues = false;
	} else if (algo == "zero") {
		fbPtr         = &MatchMaker::fbZero;
		fbNeedsValues = false;
	} else if (algo == "avg") {
		fbPtr         = &MatchMaker::fbAvg;
		fbNeedsValues = true;
	} else if (algo == "min") {
		fbPtr         = &MatchMaker::fbMin;
		fbNeedsValues = true;
	} else if (algo == "max") {
		fbPtr         = &MatchMaker::fbMax;
		fbNeedsValues = true;
	} else if (algo == "harmAvg") {
		fbPtr         = &MatchMaker::fbHarmAvg;
		fbNeedsValues = true;
	} else
		throw std::invalid_argument("MatchMaker:: algo '" + algo + "' not recognized (possible values: val, zero, avg, min, max, harmAvg).");

	// Fill matchSet with values for a fast coefficient search
	for (const auto& m : matches) {
		const int  minId  = std::min((int)m[0], (int)m[1]);
		const int  maxId  = std::max((int)m[0], (int)m[1]);
		const auto idPair = std::make_pair(minId, maxId);
		matchSet.insert(std::make_pair(idPair, m[2]));
	}
}

Real MatchMaker::computeFallback(Real v1, Real v2) const { return (this->*MatchMaker::fbPtr)(v1, v2); }

} // namespace yade
