// Boost.Geometry (aka GGL, Generic Geometry Library) test file
//
// Copyright Barend Gehrels 2007-2009, Geodan, Amsterdam, the Netherlands
// Copyright Bruno Lalande 2008, 2009
// Use, modification and distribution is subject to the Boost Software License,
// Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)

#define TEST_ARRAY

#include <sstream>

#include <boost/mpl/if.hpp>
#include <geometry_test_common.hpp>


#include <boost/geometry/algorithms/distance.hpp>
#include <boost/geometry/strategies/strategies.hpp>

#ifndef TEST_ARRAY
#include <boost/geometry/algorithms/make.hpp>
#endif

#include <boost/geometry/geometries/geometries.hpp>
#include <boost/geometry/geometries/adapted/boost_array_as_linestring.hpp>
#include <boost/geometry/geometries/adapted/c_array_cartesian.hpp>
#include <boost/geometry/geometries/adapted/tuple_cartesian.hpp>
#include <test_common/test_point.hpp>


namespace bg = boost::geometry;


// Define a custom distance strategy
// For this one, the "taxicab" distance, 
// see http://en.wikipedia.org/wiki/Taxicab_geometry

// For a point-point-distance operation, one typename Point is enough.
// For a point-segment-distance operation, there is some magic inside
// using another point type and casting if necessary. Therefore,
// two point-types are necessary.
template <typename P1, typename P2 = P1>
struct taxicab_distance
{
    static inline typename boost::geometry::coordinate_type<P1>::type apply(
                    P1 const& p1, P2 const& p2) 
    {
        using boost::geometry::get;
        using boost::geometry::math::abs;
        return abs(get<0>(p1) - get<1>(p2))
            + abs(get<1>(p1) - get<1>(p2));
    }
};



namespace boost { namespace geometry { namespace strategy { namespace distance { namespace services 
{

template <typename P1, typename P2>
struct tag<taxicab_distance<P1, P2> >
{
    typedef strategy_tag_distance_point_point type;
};


template <typename P1, typename P2>
struct return_type<taxicab_distance<P1, P2> >
{
    typedef typename coordinate_type<P1>::type type;
};


template<typename P1, typename P2, typename PN1, typename PN2>
struct similar_type<taxicab_distance<P1, P2>, PN1, PN2>
{
    typedef taxicab_distance<PN1, PN2> type;
};


template<typename P1, typename P2, typename PN1, typename PN2>
struct get_similar<taxicab_distance<P1, P2>, PN1, PN2>
{
    static inline typename similar_type
        <
            taxicab_distance<P1, P2>, PN1, PN2
        >::type apply(taxicab_distance<P1, P2> const& )
    {
        return taxicab_distance<PN1, PN2>();
    }
};

template <typename P1, typename P2>
struct comparable_type<taxicab_distance<P1, P2> >
{
    typedef taxicab_distance<P1, P2> type;
};

template <typename P1, typename P2>
struct get_comparable<taxicab_distance<P1, P2> >
{
    static inline taxicab_distance<P1, P2> apply(taxicab_distance<P1, P2> const& input)
    {
        return input;
    }
};

template <typename P1, typename P2>
struct result_from_distance<taxicab_distance<P1, P2> >
{
    template <typename T>
    static inline typename coordinate_type<P1>::type apply(taxicab_distance<P1, P2> const& , T const& value)
    {
        return value;
    }
};


}}}}} // namespace boost::geometry::strategy::distance::services




template <typename P>
void test_distance_point()
{
    namespace services = bg::strategy::distance::services;
    typedef typename bg::distance_result<P>::type return_type;

    {
        // Basic, trivial test

        P p1;
        bg::set<0>(p1, 1);
        bg::set<1>(p1, 1);

        P p2;
        bg::set<0>(p2, 2);
        bg::set<1>(p2, 2);

        return_type d = bg::distance(p1, p2);
        BOOST_CHECK_CLOSE(d, return_type(1.4142135), 0.001);

        // Test specifying strategy manually
        typename services::default_strategy<bg::point_tag, P>::type strategy;

        d = bg::distance(p1, p2, strategy);
        BOOST_CHECK_CLOSE(d, return_type(1.4142135), 0.001);

        {
            // Test custom strategy
            BOOST_CONCEPT_ASSERT( (bg::concept::PointDistanceStrategy<taxicab_distance<P> >) );

            typedef typename services::return_type<taxicab_distance<P> >::type cab_return_type;
            BOOST_MPL_ASSERT((boost::is_same<cab_return_type, typename bg::coordinate_type<P>::type>));

            taxicab_distance<P> tcd;
            cab_return_type d = bg::distance(p1, p2, tcd);

            BOOST_CHECK( bg::math::abs(d - cab_return_type(2)) <= cab_return_type(0.01) );
        }
    }


    {
        // 3-4-5 angle
        P p1, p2, p3;
        bg::set<0>(p1, 0); bg::set<1>(p1, 0);
        bg::set<0>(p2, 3); bg::set<1>(p2, 0);
        bg::set<0>(p3, 0); bg::set<1>(p3, 4);

        return_type dr12 = bg::distance(p1, p2);
        return_type dr13 = bg::distance(p1, p3);
        return_type dr23 = bg::distance(p2, p3);

        BOOST_CHECK_CLOSE(dr12, return_type(3), 0.001);
        BOOST_CHECK_CLOSE(dr13, return_type(4), 0.001);
        BOOST_CHECK_CLOSE(dr23, return_type(5), 0.001);
    }


    {
        // test comparability

        typedef typename services::default_strategy<bg::point_tag, P>::type strategy_type;
        typedef typename services::comparable_type<strategy_type>::type comparable_strategy_type;

        strategy_type strategy;
        comparable_strategy_type comparable_strategy = services::get_comparable<strategy_type>::apply(strategy);
        return_type comparable = services::result_from_distance<comparable_strategy_type>::apply(comparable_strategy, 3);

        BOOST_CHECK_CLOSE(comparable, return_type(9), 0.001);
    }
}

template <typename P>
void test_distance_segment()
{
    typedef typename bg::distance_result<P>::type return_type;
    typedef typename bg::coordinate_type<P>::type coordinate_type;

    P s1; bg::set<0>(s1, 1); bg::set<1>(s1, 1);
    P s2; bg::set<0>(s2, 4); bg::set<1>(s2, 4);

    // Check points left, right, projected-left, projected-right, on segment
    P p1; bg::set<0>(p1, 0); bg::set<1>(p1, 1);
    P p2; bg::set<0>(p2, 1); bg::set<1>(p2, 0);
    P p3; bg::set<0>(p3, 3); bg::set<1>(p3, 1);
    P p4; bg::set<0>(p4, 1); bg::set<1>(p4, 3);
    P p5; bg::set<0>(p5, 3); bg::set<1>(p5, 3);

    bg::segment<P const> const seg(s1, s2);

    return_type d1 = bg::distance(p1, seg); 
    return_type d2 = bg::distance(p2, seg); 
    return_type d3 = bg::distance(p3, seg); 
    return_type d4 = bg::distance(p4, seg); 
    return_type d5 = bg::distance(p5, seg); 

    BOOST_CHECK_CLOSE(d1, return_type(1), 0.001);
    BOOST_CHECK_CLOSE(d2, return_type(1), 0.001);
    BOOST_CHECK_CLOSE(d3, return_type(1.4142135), 0.001);
    BOOST_CHECK_CLOSE(d4, return_type(1.4142135), 0.001);
    BOOST_CHECK_CLOSE(d5, return_type(0), 0.001);

    // Reverse case: segment/point instead of point/segment
    return_type dr1 = bg::distance(seg, p1); 
    return_type dr2 = bg::distance(seg, p2); 

    BOOST_CHECK_CLOSE(dr1, d1, 0.001);
    BOOST_CHECK_CLOSE(dr2, d2, 0.001);

    // Test specifying strategy manually:
    // 1) point-point-distance
    typename bg::strategy::distance::services::default_strategy<bg::point_tag, P>::type pp_strategy;
    d1 = bg::distance(p1, seg, pp_strategy); 
    BOOST_CHECK_CLOSE(d1, return_type(1), 0.001);

    // 2) point-segment-distance
    typename bg::strategy::distance::services::default_strategy<bg::segment_tag, P>::type ps_strategy;
    d1 = bg::distance(p1, seg, ps_strategy); 
    BOOST_CHECK_CLOSE(d1, return_type(1), 0.001);

    // 3) custom point strategy
    taxicab_distance<P> tcd;
    return_type d = bg::distance(p1, seg, tcd);
    BOOST_CHECK_CLOSE(d1, return_type(1), 0.001);
}


template <typename P>
void test_distance_linestring()
{
    typedef typename bg::distance_result<P>::type return_type;

    boost::array<P, 2> points;
    bg::set<0>(points[0], 1);
    bg::set<1>(points[0], 1);
    bg::set<0>(points[1], 3);
    bg::set<1>(points[1], 3);

    P p;
    bg::set<0>(p, 2); bg::set<1>(p, 1);

    return_type d = bg::distance(p, points);
    BOOST_CHECK_CLOSE(d, return_type(0.70710678), 0.001);

    bg::set<0>(p, 5); bg::set<1>(p, 5);
    d = bg::distance(p, points);
    BOOST_CHECK_CLOSE(d, return_type(2.828427), 0.001);


    bg::linestring<P> line;
    {
        P lp;
        bg::set<0>(lp, 1); bg::set<1>(lp, 1); line.push_back(lp);
        bg::set<0>(lp, 2); bg::set<1>(lp, 2); line.push_back(lp);
        bg::set<0>(lp, 3); bg::set<1>(lp, 3); line.push_back(lp);
    }

    bg::set<0>(p, 5); bg::set<1>(p, 5);

    d = bg::distance(p, line);
    BOOST_CHECK_CLOSE(d, return_type(2.828427), 0.001);

    // Reverse case: line/point instead of point/line
    d = bg::distance(line, p);
    BOOST_CHECK_CLOSE(d, return_type(2.828427), 0.001);
}


template <typename P>
void test_distance_ring()
{
    typedef typename bg::distance_result<P>::type return_type;

    bg::linear_ring<P> ring;
    {
        P lp;
        bg::set<0>(lp, 1); bg::set<1>(lp, 1); line.push_back(lp);
        bg::set<0>(lp, 2); bg::set<1>(lp, 2); line.push_back(lp);
        bg::set<0>(lp, 3); bg::set<1>(lp, 3); line.push_back(lp);
    }

    bg::set<0>(p, 5); bg::set<1>(p, 5);

    d = bg::distance(p, line);
    BOOST_CHECK_CLOSE(d, return_type(2.828427), 0.001);

    // Reverse case: line/point instead of point/line
    d = bg::distance(line, p);
    BOOST_CHECK_CLOSE(d, return_type(2.828427), 0.001);
}


template <typename P>
void test_all()
{
    test_distance_point<P>();
    test_distance_segment<P>();
    test_distance_linestring<P>();
}

int test_main(int, char* [])
{
#ifdef TEST_ARRAY
    //test_all<int[2]>();
    //test_all<float[2]>();
    //test_all<double[2]>();
    //test_all<test::test_point>(); // located here because of 3D
#endif

    test_all<bg::point_xy<int> >();
    test_all<boost::tuple<float, float> >();
    test_all<bg::point_xy<float> >();
    test_all<bg::point_xy<double> >();

    return 0;
}