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/* Author: Ioan Sucan */

#ifndef OMPL_BASE_GOALS_GOAL_SAMPLEABLE_REGION_
#define OMPL_BASE_GOALS_GOAL_SAMPLEABLE_REGION_

#include "ompl/base/goals/GoalRegion.h"

namespace ompl
{

    namespace base
    {

        /** \brief Abstract definition of a goal region that can be sampled */
        class GoalSampleableRegion : public GoalRegion
        {
        public:

            /** \brief Create a goal region that can be sampled */
            GoalSampleableRegion(const SpaceInformationPtr &si) : GoalRegion(si)
            {
                type_ = GOAL_SAMPLEABLE_REGION;
            }

            virtual ~GoalSampleableRegion()
            {
            }

            /** \brief Sample a state in the goal region */
            virtual void sampleGoal(State *st) const = 0;

            /** \brief Return the maximum number of samples that can be asked for before repeating */
            virtual unsigned int maxSampleCount() const = 0;

            /** \brief Return true if maxSampleCount() > 0, since in this case samples can certainly be produced */
            bool canSample() const
            {
                return maxSampleCount() > 0;
            }

            /** \brief Return true if samples could be generated by this sampler at some point in the future. By default this is equivalent to canSample(),
             but for GoalLazySamples, this call also reflects the fact that a sampling thread is active and although no samples are produced yet, some may
             become available at some point in the future. */
            virtual bool couldSample() const
            {
                return canSample();
            }

        };

    }
}

#endif
