#ifndef GEOSPATIAL_QUERY_HPP
#define GEOSPATIAL_QUERY_HPP

#include "engine/phantom_node.hpp"
#include "util/bearing.hpp"
#include "util/coordinate_calculation.hpp"
#include "util/rectangle.hpp"
#include "util/typedefs.hpp"
#include "util/web_mercator.hpp"

#include "osrm/coordinate.hpp"

#include <algorithm>
#include <cmath>
#include <memory>
#include <vector>

namespace osrm
{
namespace engine
{

inline std::pair<bool, bool> boolPairAnd(const std::pair<bool, bool> &A,
                                         const std::pair<bool, bool> &B)
{
    return std::make_pair(A.first && B.first, A.second && B.second);
}

// Implements complex queries on top of an RTree and builds PhantomNodes from it.
//
// Only holds a weak reference on the RTree and coordinates!
template <typename RTreeT, typename DataFacadeT> class GeospatialQuery
{
    using EdgeData = typename RTreeT::EdgeData;
    using CoordinateList = typename RTreeT::CoordinateList;
    using CandidateSegment = typename RTreeT::CandidateSegment;

  public:
    GeospatialQuery(RTreeT &rtree_, const CoordinateList &coordinates_, DataFacadeT &datafacade_)
        : rtree(rtree_), coordinates(coordinates_), datafacade(datafacade_)
    {
    }

    std::vector<EdgeData> Search(const util::RectangleInt2D &bbox)
    {
        return rtree.SearchInBox(bbox);
    }

    // Returns nearest PhantomNodes in the given bearing range within max_distance.
    // Does not filter by small/big component!
    std::vector<PhantomNodeWithDistance>
    NearestPhantomNodesInRange(const util::Coordinate input_coordinate,
                               const double max_distance) const
    {
        auto results =
            rtree.Nearest(input_coordinate,
                          [this](const CandidateSegment &segment) { return HasValidEdge(segment); },
                          [this, max_distance, input_coordinate](const std::size_t,
                                                                 const CandidateSegment &segment) {
                              return CheckSegmentDistance(input_coordinate, segment, max_distance);
                          });

        return MakePhantomNodes(input_coordinate, results);
    }

    // Returns nearest PhantomNodes in the given bearing range within max_distance.
    // Does not filter by small/big component!
    std::vector<PhantomNodeWithDistance>
    NearestPhantomNodesInRange(const util::Coordinate input_coordinate,
                               const double max_distance,
                               const int bearing,
                               const int bearing_range) const
    {
        auto results = rtree.Nearest(
            input_coordinate,
            [this, bearing, bearing_range, max_distance](const CandidateSegment &segment) {
                return boolPairAnd(CheckSegmentBearing(segment, bearing, bearing_range),
                                   HasValidEdge(segment));
            },
            [this, max_distance, input_coordinate](const std::size_t,
                                                   const CandidateSegment &segment) {
                return CheckSegmentDistance(input_coordinate, segment, max_distance);
            });

        return MakePhantomNodes(input_coordinate, results);
    }

    // Returns max_results nearest PhantomNodes in the given bearing range.
    // Does not filter by small/big component!
    std::vector<PhantomNodeWithDistance>
    NearestPhantomNodes(const util::Coordinate input_coordinate,
                        const unsigned max_results,
                        const int bearing,
                        const int bearing_range) const
    {
        auto results = rtree.Nearest(
            input_coordinate,
            [this, bearing, bearing_range](const CandidateSegment &segment) {
                return boolPairAnd(CheckSegmentBearing(segment, bearing, bearing_range),
                                   HasValidEdge(segment));
            },
            [max_results](const std::size_t num_results, const CandidateSegment &) {
                return num_results >= max_results;
            });

        return MakePhantomNodes(input_coordinate, results);
    }

    // Returns max_results nearest PhantomNodes in the given bearing range within the maximum
    // distance.
    // Does not filter by small/big component!
    std::vector<PhantomNodeWithDistance>
    NearestPhantomNodes(const util::Coordinate input_coordinate,
                        const unsigned max_results,
                        const double max_distance,
                        const int bearing,
                        const int bearing_range) const
    {
        auto results = rtree.Nearest(
            input_coordinate,
            [this, bearing, bearing_range](const CandidateSegment &segment) {
                return boolPairAnd(CheckSegmentBearing(segment, bearing, bearing_range),
                                   HasValidEdge(segment));
            },
            [this, max_distance, max_results, input_coordinate](const std::size_t num_results,
                                                                const CandidateSegment &segment) {
                return num_results >= max_results ||
                       CheckSegmentDistance(input_coordinate, segment, max_distance);
            });

        return MakePhantomNodes(input_coordinate, results);
    }

    // Returns max_results nearest PhantomNodes.
    // Does not filter by small/big component!
    std::vector<PhantomNodeWithDistance>
    NearestPhantomNodes(const util::Coordinate input_coordinate, const unsigned max_results) const
    {
        auto results =
            rtree.Nearest(input_coordinate,
                          [this](const CandidateSegment &segment) { return HasValidEdge(segment); },
                          [max_results](const std::size_t num_results, const CandidateSegment &) {
                              return num_results >= max_results;
                          });

        return MakePhantomNodes(input_coordinate, results);
    }

    // Returns max_results nearest PhantomNodes in the given max distance.
    // Does not filter by small/big component!
    std::vector<PhantomNodeWithDistance>
    NearestPhantomNodes(const util::Coordinate input_coordinate,
                        const unsigned max_results,
                        const double max_distance) const
    {
        auto results =
            rtree.Nearest(input_coordinate,
                          [this](const CandidateSegment &segment) { return HasValidEdge(segment); },
                          [this, max_distance, max_results, input_coordinate](
                              const std::size_t num_results, const CandidateSegment &segment) {
                              return num_results >= max_results ||
                                     CheckSegmentDistance(input_coordinate, segment, max_distance);
                          });

        return MakePhantomNodes(input_coordinate, results);
    }

    // Returns the nearest phantom node. If this phantom node is not from a big component
    // a second phantom node is return that is the nearest coordinate in a big component.
    std::pair<PhantomNode, PhantomNode>
    NearestPhantomNodeWithAlternativeFromBigComponent(const util::Coordinate input_coordinate,
                                                      const double max_distance) const
    {
        bool has_small_component = false;
        bool has_big_component = false;
        auto results = rtree.Nearest(
            input_coordinate,
            [this, &has_big_component, &has_small_component](const CandidateSegment &segment) {
                auto use_segment = (!has_small_component ||
                                    (!has_big_component && !segment.data.component.is_tiny));
                auto use_directions = std::make_pair(use_segment, use_segment);
                const auto valid_edges = HasValidEdge(segment);

                if (valid_edges.first || valid_edges.second)
                {
                    has_big_component = has_big_component || !segment.data.component.is_tiny;
                    has_small_component = has_small_component || segment.data.component.is_tiny;
                }
                use_directions = boolPairAnd(use_directions, valid_edges);
                return use_directions;
            },
            [this, &has_big_component, max_distance, input_coordinate](
                const std::size_t num_results, const CandidateSegment &segment) {
                return (num_results > 0 && has_big_component) ||
                       CheckSegmentDistance(input_coordinate, segment, max_distance);
            });

        if (results.size() == 0)
        {
            return std::make_pair(PhantomNode{}, PhantomNode{});
        }

        BOOST_ASSERT(results.size() == 1 || results.size() == 2);
        return std::make_pair(MakePhantomNode(input_coordinate, results.front()).phantom_node,
                              MakePhantomNode(input_coordinate, results.back()).phantom_node);
    }

    // Returns the nearest phantom node. If this phantom node is not from a big component
    // a second phantom node is return that is the nearest coordinate in a big component.
    std::pair<PhantomNode, PhantomNode>
    NearestPhantomNodeWithAlternativeFromBigComponent(const util::Coordinate input_coordinate) const
    {
        bool has_small_component = false;
        bool has_big_component = false;
        auto results = rtree.Nearest(
            input_coordinate,
            [this, &has_big_component, &has_small_component](const CandidateSegment &segment) {
                auto use_segment = (!has_small_component ||
                                    (!has_big_component && !segment.data.component.is_tiny));
                auto use_directions = std::make_pair(use_segment, use_segment);
                if (!use_directions.first && !use_directions.second)
                    return use_directions;
                const auto valid_edges = HasValidEdge(segment);

                if (valid_edges.first || valid_edges.second)
                {

                    has_big_component = has_big_component || !segment.data.component.is_tiny;
                    has_small_component = has_small_component || segment.data.component.is_tiny;
                }

                use_directions = boolPairAnd(use_directions, valid_edges);
                return use_directions;
            },
            [&has_big_component](const std::size_t num_results, const CandidateSegment &) {
                return num_results > 0 && has_big_component;
            });

        if (results.size() == 0)
        {
            return std::make_pair(PhantomNode{}, PhantomNode{});
        }

        BOOST_ASSERT(results.size() == 1 || results.size() == 2);
        return std::make_pair(MakePhantomNode(input_coordinate, results.front()).phantom_node,
                              MakePhantomNode(input_coordinate, results.back()).phantom_node);
    }

    // Returns the nearest phantom node. If this phantom node is not from a big component
    // a second phantom node is return that is the nearest coordinate in a big component.
    std::pair<PhantomNode, PhantomNode> NearestPhantomNodeWithAlternativeFromBigComponent(
        const util::Coordinate input_coordinate, const int bearing, const int bearing_range) const
    {
        bool has_small_component = false;
        bool has_big_component = false;
        auto results = rtree.Nearest(
            input_coordinate,
            [this, bearing, bearing_range, &has_big_component, &has_small_component](
                const CandidateSegment &segment) {
                auto use_segment = (!has_small_component ||
                                    (!has_big_component && !segment.data.component.is_tiny));
                auto use_directions = std::make_pair(use_segment, use_segment);
                use_directions = boolPairAnd(use_directions, HasValidEdge(segment));

                if (use_segment)
                {
                    use_directions =
                        boolPairAnd(CheckSegmentBearing(segment, bearing, bearing_range),
                                    HasValidEdge(segment));
                    if (use_directions.first || use_directions.second)
                    {
                        has_big_component = has_big_component || !segment.data.component.is_tiny;
                        has_small_component = has_small_component || segment.data.component.is_tiny;
                    }
                }

                return use_directions;
            },
            [&has_big_component](const std::size_t num_results, const CandidateSegment &) {
                return num_results > 0 && has_big_component;
            });

        if (results.size() == 0)
        {
            return std::make_pair(PhantomNode{}, PhantomNode{});
        }

        BOOST_ASSERT(results.size() > 0);
        return std::make_pair(MakePhantomNode(input_coordinate, results.front()).phantom_node,
                              MakePhantomNode(input_coordinate, results.back()).phantom_node);
    }

    // Returns the nearest phantom node. If this phantom node is not from a big component
    // a second phantom node is return that is the nearest coordinate in a big component.
    std::pair<PhantomNode, PhantomNode>
    NearestPhantomNodeWithAlternativeFromBigComponent(const util::Coordinate input_coordinate,
                                                      const double max_distance,
                                                      const int bearing,
                                                      const int bearing_range) const
    {
        bool has_small_component = false;
        bool has_big_component = false;
        auto results = rtree.Nearest(
            input_coordinate,
            [this, bearing, bearing_range, &has_big_component, &has_small_component](
                const CandidateSegment &segment) {
                auto use_segment = (!has_small_component ||
                                    (!has_big_component && !segment.data.component.is_tiny));
                auto use_directions = std::make_pair(use_segment, use_segment);
                use_directions = boolPairAnd(use_directions, HasValidEdge(segment));

                if (use_segment)
                {
                    use_directions =
                        boolPairAnd(CheckSegmentBearing(segment, bearing, bearing_range),
                                    HasValidEdge(segment));
                    if (use_directions.first || use_directions.second)
                    {
                        has_big_component = has_big_component || !segment.data.component.is_tiny;
                        has_small_component = has_small_component || segment.data.component.is_tiny;
                    }
                }

                return use_directions;
            },
            [this, &has_big_component, max_distance, input_coordinate](
                const std::size_t num_results, const CandidateSegment &segment) {
                return (num_results > 0 && has_big_component) ||
                       CheckSegmentDistance(input_coordinate, segment, max_distance);
            });

        if (results.size() == 0)
        {
            return std::make_pair(PhantomNode{}, PhantomNode{});
        }

        BOOST_ASSERT(results.size() > 0);
        return std::make_pair(MakePhantomNode(input_coordinate, results.front()).phantom_node,
                              MakePhantomNode(input_coordinate, results.back()).phantom_node);
    }

  private:
    std::vector<PhantomNodeWithDistance>
    MakePhantomNodes(const util::Coordinate input_coordinate,
                     const std::vector<EdgeData> &results) const
    {
        std::vector<PhantomNodeWithDistance> distance_and_phantoms(results.size());
        std::transform(results.begin(),
                       results.end(),
                       distance_and_phantoms.begin(),
                       [this, &input_coordinate](const EdgeData &data) {
                           return MakePhantomNode(input_coordinate, data);
                       });
        return distance_and_phantoms;
    }

    PhantomNodeWithDistance MakePhantomNode(const util::Coordinate input_coordinate,
                                            const EdgeData &data) const
    {
        util::Coordinate point_on_segment;
        double ratio;
        const auto current_perpendicular_distance =
            util::coordinate_calculation::perpendicularDistance(coordinates[data.u],
                                                                coordinates[data.v],
                                                                input_coordinate,
                                                                point_on_segment,
                                                                ratio);

        // Find the node-based-edge that this belongs to, and directly
        // calculate the forward_weight, forward_offset, reverse_weight, reverse_offset

        int forward_offset = 0, forward_weight = 0;
        int reverse_offset = 0, reverse_weight = 0;

        const std::vector<EdgeWeight> forward_weight_vector =
            datafacade.GetUncompressedForwardWeights(data.packed_geometry_id);
        const std::vector<EdgeWeight> reverse_weight_vector =
            datafacade.GetUncompressedReverseWeights(data.packed_geometry_id);

        for (std::size_t i = 0; i < data.fwd_segment_position; i++)
        {
            forward_offset += forward_weight_vector[i];
        }
        forward_weight = forward_weight_vector[data.fwd_segment_position];

        BOOST_ASSERT(data.fwd_segment_position < reverse_weight_vector.size());

        for (std::size_t i = 0; i < reverse_weight_vector.size() - data.fwd_segment_position - 1;
             i++)
        {
            reverse_offset += reverse_weight_vector[i];
        }
        reverse_weight =
            reverse_weight_vector[reverse_weight_vector.size() - data.fwd_segment_position - 1];

        ratio = std::min(1.0, std::max(0.0, ratio));
        if (data.forward_segment_id.id != SPECIAL_SEGMENTID)
        {
            forward_weight *= ratio;
        }
        if (data.reverse_segment_id.id != SPECIAL_SEGMENTID)
        {
            reverse_weight *= 1.0 - ratio;
        }

        auto transformed = PhantomNodeWithDistance{PhantomNode{data,
                                                               forward_weight,
                                                               forward_offset,
                                                               reverse_weight,
                                                               reverse_offset,
                                                               point_on_segment,
                                                               input_coordinate},
                                                   current_perpendicular_distance};

        return transformed;
    }

    bool CheckSegmentDistance(const Coordinate input_coordinate,
                              const CandidateSegment &segment,
                              const double max_distance) const
    {
        BOOST_ASSERT(segment.data.forward_segment_id.id != SPECIAL_SEGMENTID ||
                     !segment.data.forward_segment_id.enabled);
        BOOST_ASSERT(segment.data.reverse_segment_id.id != SPECIAL_SEGMENTID ||
                     !segment.data.reverse_segment_id.enabled);

        Coordinate wsg84_coordinate =
            util::web_mercator::toWGS84(segment.fixed_projected_coordinate);

        return util::coordinate_calculation::haversineDistance(input_coordinate, wsg84_coordinate) >
               max_distance;
    }

    std::pair<bool, bool> CheckSegmentBearing(const CandidateSegment &segment,
                                              const int filter_bearing,
                                              const int filter_bearing_range) const
    {
        BOOST_ASSERT(segment.data.forward_segment_id.id != SPECIAL_SEGMENTID ||
                     !segment.data.forward_segment_id.enabled);
        BOOST_ASSERT(segment.data.reverse_segment_id.id != SPECIAL_SEGMENTID ||
                     !segment.data.reverse_segment_id.enabled);

        const double forward_edge_bearing = util::coordinate_calculation::bearing(
            coordinates[segment.data.u], coordinates[segment.data.v]);

        const double backward_edge_bearing = (forward_edge_bearing + 180) > 360
                                                 ? (forward_edge_bearing - 180)
                                                 : (forward_edge_bearing + 180);

        const bool forward_bearing_valid =
            util::bearing::CheckInBounds(
                std::round(forward_edge_bearing), filter_bearing, filter_bearing_range) &&
            segment.data.forward_segment_id.enabled;
        const bool backward_bearing_valid =
            util::bearing::CheckInBounds(
                std::round(backward_edge_bearing), filter_bearing, filter_bearing_range) &&
            segment.data.reverse_segment_id.enabled;
        return std::make_pair(forward_bearing_valid, backward_bearing_valid);
    }

    /**
     * Checks to see if the edge weights are valid.  We might have an edge,
     * but a traffic update might set the speed to 0 (weight == INVALID_EDGE_WEIGHT).
     * which means that this edge is not currently traversible.  If this is the case,
     * then we shouldn't snap to this edge.
     */
    std::pair<bool, bool> HasValidEdge(const CandidateSegment &segment) const
    {

        bool forward_edge_valid = false;
        bool reverse_edge_valid = false;

        const std::vector<EdgeWeight> forward_weight_vector =
            datafacade.GetUncompressedForwardWeights(segment.data.packed_geometry_id);

        if (forward_weight_vector[segment.data.fwd_segment_position] != INVALID_EDGE_WEIGHT)
        {
            forward_edge_valid = segment.data.forward_segment_id.enabled;
        }

        const std::vector<EdgeWeight> reverse_weight_vector =
            datafacade.GetUncompressedReverseWeights(segment.data.packed_geometry_id);
        if (reverse_weight_vector[reverse_weight_vector.size() - segment.data.fwd_segment_position -
                                  1] != INVALID_EDGE_WEIGHT)
        {
            reverse_edge_valid = segment.data.reverse_segment_id.enabled;
        }

        return std::make_pair(forward_edge_valid, reverse_edge_valid);
    }

    const RTreeT &rtree;
    const CoordinateList &coordinates;
    DataFacadeT &datafacade;
};
}
}

#endif
