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/* Author: Luis G. Torres */

#include "ompl/base/objectives/MechanicalWorkOptimizationObjective.h"

ompl::base::MechanicalWorkOptimizationObjective::MechanicalWorkOptimizationObjective(const SpaceInformationPtr &si,
                                                                                     double pathLengthWeight)
  : OptimizationObjective(si), pathLengthWeight_(pathLengthWeight)
{
    description_ = "Mechanical Work";
}

double ompl::base::MechanicalWorkOptimizationObjective::getPathLengthWeight() const
{
    return pathLengthWeight_;
}

ompl::base::Cost ompl::base::MechanicalWorkOptimizationObjective::stateCost(const State *s) const
{
    return Cost(1.0);
}

ompl::base::Cost ompl::base::MechanicalWorkOptimizationObjective::motionCost(const State *s1, const State *s2) const
{
    // Only accrue positive changes in cost
    double positiveCostAccrued = std::max(stateCost(s2).value() - stateCost(s1).value(), 0.0);
    return Cost(positiveCostAccrued + pathLengthWeight_ * si_->distance(s1, s2));
}
