/*
  Copyright 2012 SINTEF ICT, Applied Mathematics.

  This file is part of the Open Porous Media project (OPM).

  OPM 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.

  OPM 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 OPM.  If not, see <http://www.gnu.org/licenses/>.
*/

#include <opm/core/utility/SimulatorTimer.hpp>
#include <opm/core/utility/parameters/ParameterGroup.hpp>
#include <opm/core/utility/Units.hpp>
#include <opm/core/eclipse/EclipseGridParser.hpp>
#include <ostream>
#include <numeric>

namespace Opm
{

    /// Default constructor.
    SimulatorTimer::SimulatorTimer()
	: current_step_(0),
	  current_time_(0.0)
    {
    }

    /// Initialize from parameters. Accepts the following:
    ///    num_psteps    (default 1)
    ///    stepsize_days (default 1)
    void SimulatorTimer::init(const parameter::ParameterGroup& param)
    {
	const int num_psteps = param.getDefault("num_psteps", 1);
	const double stepsize_days = param.getDefault("stepsize_days", 1.0);
	const double stepsize = Opm::unit::convert::from(stepsize_days, Opm::unit::day);
	timesteps_.clear();
	timesteps_.resize(num_psteps, stepsize);
	total_time_ = num_psteps*stepsize;
    }

    /// Initialize from TSTEP field.
    void SimulatorTimer::init(const EclipseGridParser& deck)
    {
	timesteps_ = deck.getTSTEP().tstep_;
	total_time_ = std::accumulate(timesteps_.begin(), timesteps_.end(), 0.0);
    }

    /// Total number of steps.
    int SimulatorTimer::numSteps() const
    {
	return timesteps_.size();
    }

    /// Current step number.
    int SimulatorTimer::currentStepNum() const
    {
	return current_step_;
    }

    /// Current step length.
    double SimulatorTimer::currentStepLength() const
    {
	ASSERT(!done());
	return timesteps_[current_step_];
    }

    /// Current time.
    double SimulatorTimer::currentTime() const
    {
	return current_time_;
    }

    /// Total time.
    double SimulatorTimer::totalTime() const
    {
	return total_time_;
    }

    /// Print a report with current and total time etc.
    void SimulatorTimer::report(std::ostream& os) const
    {
        os << "\n\n---------------    Simulation step number " << currentStepNum() << "    ---------------"
	   << "\n      Current time (days)     " << Opm::unit::convert::to(currentTime(), Opm::unit::day)
	   << "\n      Current stepsize (days) " << Opm::unit::convert::to(currentStepLength(), Opm::unit::day)
	   << "\n      Total time (days)       " << Opm::unit::convert::to(totalTime(), Opm::unit::day)
	   << "\n" << std::endl;
    }

    /// Next step.
    SimulatorTimer& SimulatorTimer::operator++()
    {
	ASSERT(!done());
	current_time_ += timesteps_[current_step_];
	++current_step_;
	return *this;
    }

    /// Return true if op++() has been called numSteps() times.
    bool SimulatorTimer::done() const
    {
	return int(timesteps_.size()) == current_step_;
    }


} // namespace Opm