AStarPriorityQueue.h

#pragma once

#include "Graphs.h"
#include "Types.h"
#include "AStarState.h"

#include <queue>


namespace Eegeo
{
    namespace Graphs
    {
        class AStarStatePriorityComparer
        {
        public:
            AStarStatePriorityComparer(const std::vector<AStarState>& astarStateVector)
                : m_astarStateVector(astarStateVector)
            {}

            inline bool operator ()(const int ia, const int ib) const
            {
                const auto& a = m_astarStateVector.at(ia);
                const auto& b = m_astarStateVector.at(ib);
                return a.F() > b.F();
            }
        private:
            const std::vector<AStarState>& m_astarStateVector;

        };

        struct AStarPriorityQueueTraits
        {
            using container_type = std::vector<int>;
            using predicate_type = AStarStatePriorityComparer;
            using type = std::priority_queue<int, container_type, predicate_type>;
        };

        class AStarPriorityQueue : public AStarPriorityQueueTraits::type, private Eegeo::NonCopyable
        {
        public:
            AStarPriorityQueue(const AStarPriorityQueueTraits::predicate_type& comparer)
                : AStarPriorityQueueTraits::type(comparer)
            {}

            void reorder()
            {
                std::make_heap(std::begin(c), std::end(c), comp);
            }
        };
    }
}