// This file is part of BUDEES, a software that allows fast simulation of bubble dynamics in electrolyzers and their interactions with electrical parameters. 
// 
// Copyright (C) 2024 <CNRS-ENS Rennes-Université de Rennes-CY Cergy Paris Université-Université Paris Saclay-CNAM Paris-ENS Paris-Saclay>
// 
// 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 https://www.gnu.org/licenses/



TimeSteps updateTimestep(TimeSteps& timesteps, double maxRadius, double maxVelocity, vector<Site>& Sites, bool* stopFlag) {
	// Nucleation growing rate
	double growingFactorMax = 0;
	for (vector<Site>::iterator it = Sites.begin(); it != Sites.end(); it++)
		growingFactorMax = MAX(growingFactorMax, it->growth);
	double TgrowthMin = RFritzMin/growingFactorMax;
	double dtMaximal1 = TgrowthMin/GROWING_TIME_COEF;

	// Equilibrium buoyancy velocity
	double UElec = abs(bPrefactor*mathSQ(maxRadius));
	double dtElec = 2*maxRadius/(ELECTRICAL_TIME_COEF*UElec);

	// Check Reynolds
	double U = abs(bPrefactor*mathSQ(maxRadius));
	double dtMaximal2 = 2*maxRadius/(BUOYANCY_TIME_COEF*U);
	double reynolds = (rho/mu)*maxVelocity*maxRadius;
	if (reynolds > 10) {
		errorProgress("reynolds number too high (Re=" + std::to_string(reynolds) + ")");
		*stopFlag = true;
	}

	// Return the smallest value
	double dt = MIN(dtMaximal1, dtMaximal2);

	return {dt, dtElec, timesteps.i, timesteps.iElec};
}