// Boost.Geometry (aka GGL, Generic Geometry Library)

// Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
// Copyright (c) 2008-2012 Bruno Lalande, Paris, France.
// Copyright (c) 2009-2012 Mateusz Loskot, London, UK.
// Copyright (c) 2013 Adam Wulkiewicz, Lodz, Poland.

// This file was modified by Oracle on 2013, 2014.
// Modifications copyright (c) 2013, 2014, Oracle and/or its affiliates.

// Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
// (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands.

// 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)

// Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle

#ifndef BOOST_GEOMETRY_ALGORITHMS_TOUCHES_HPP
#define BOOST_GEOMETRY_ALGORITHMS_TOUCHES_HPP


#include <deque>

#include <boost/variant/apply_visitor.hpp>
#include <boost/variant/static_visitor.hpp>
#include <boost/variant/variant_fwd.hpp>

#include <boost/geometry/geometries/concepts/check.hpp>
#include <boost/geometry/algorithms/detail/for_each_range.hpp>
#include <boost/geometry/algorithms/detail/overlay/overlay.hpp>
#include <boost/geometry/algorithms/detail/overlay/self_turn_points.hpp>
#include <boost/geometry/algorithms/disjoint.hpp>
#include <boost/geometry/algorithms/intersects.hpp>
#include <boost/geometry/algorithms/num_geometries.hpp>
#include <boost/geometry/algorithms/detail/sub_range.hpp>
#include <boost/geometry/policies/robustness/no_rescale_policy.hpp>

#include <boost/geometry/algorithms/detail/relate/relate.hpp>

namespace boost { namespace geometry
{

#ifndef DOXYGEN_NO_DETAIL
namespace detail { namespace touches
{

// Box/Box

template
<
    std::size_t Dimension,
    std::size_t DimensionCount
>
struct box_box_loop
{
    template <typename Box1, typename Box2>
    static inline bool apply(Box1 const& b1, Box2 const& b2, bool & touch)
    {
        typedef typename coordinate_type<Box1>::type coordinate_type1;
        typedef typename coordinate_type<Box2>::type coordinate_type2;

        coordinate_type1 const& min1 = get<min_corner, Dimension>(b1);
        coordinate_type1 const& max1 = get<max_corner, Dimension>(b1);
        coordinate_type2 const& min2 = get<min_corner, Dimension>(b2);
        coordinate_type2 const& max2 = get<max_corner, Dimension>(b2);

        // TODO assert or exception?
        //BOOST_ASSERT(min1 <= max1 && min2 <= max2);

        if ( max1 < min2 || max2 < min1 )
        {
            return false;
        }

        if ( max1 == min2 || max2 == min1 )
        {
            touch = true;
        }
        
        return box_box_loop
                <
                    Dimension + 1,
                    DimensionCount
                >::apply(b1, b2, touch);
    }
};

template
<
    std::size_t DimensionCount
>
struct box_box_loop<DimensionCount, DimensionCount>
{
    template <typename Box1, typename Box2>
    static inline bool apply(Box1 const& , Box2 const&, bool &)
    {
        return true;
    }
};

struct box_box
{
    template <typename Box1, typename Box2>
    static inline bool apply(Box1 const& b1, Box2 const& b2)
    {
        BOOST_STATIC_ASSERT((boost::is_same
                                <
                                    typename geometry::coordinate_system<Box1>::type,
                                    typename geometry::coordinate_system<Box2>::type
                                >::value
                           ));
        assert_dimension_equal<Box1, Box2>();

        bool touches = false;
        bool ok = box_box_loop
                    <
                        0,
                        dimension<Box1>::type::value
                    >::apply(b1, b2, touches);

        return ok && touches;
    }
};

// Areal/Areal

struct areal_interrupt_policy
{
    static bool const enabled = true;
    bool found_touch;
    bool found_not_touch;

    // dummy variable required by self_get_turn_points::get_turns
    static bool const has_intersections = false;

    inline bool result()
    {
        return found_touch && !found_not_touch;
    }

    inline areal_interrupt_policy()
        : found_touch(false), found_not_touch(false)
    {}

    template <typename Range>
    inline bool apply(Range const& range)
    {
        // if already rejected (temp workaround?)
        if ( found_not_touch )
            return true;

        typedef typename boost::range_iterator<Range const>::type iterator;
        for ( iterator it = boost::begin(range) ; it != boost::end(range) ; ++it )
        {
            if ( it->has(overlay::operation_intersection) )
            {
                found_not_touch = true;
                return true;
            }

            switch(it->method)
            {
                case overlay::method_crosses:
                    found_not_touch = true;
                    return true;
                case overlay::method_equal:
                    // Segment spatially equal means: at the right side
                    // the polygon internally overlaps. So return false.
                    found_not_touch = true;
                    return true;
                case overlay::method_touch:
                case overlay::method_touch_interior:
                case overlay::method_collinear:
                    if ( ok_for_touch(*it) )
                    {
                        found_touch = true;
                    }
                    else
                    {
                        found_not_touch = true;
                        return true;
                    }
                    break;
                case overlay::method_none :
                case overlay::method_disjoint :
                case overlay::method_error :
                    break;
            }
        }

        return false;
    }

    template <typename Turn>
    inline bool ok_for_touch(Turn const& turn)
    {
        return turn.both(overlay::operation_union)
            || turn.both(overlay::operation_blocked)
            || turn.combination(overlay::operation_union, overlay::operation_blocked)
            ;
    }
};

template<typename Geometry>
struct check_each_ring_for_within
{
    bool has_within;
    Geometry const& m_geometry;

    inline check_each_ring_for_within(Geometry const& g)
        : has_within(false)
        , m_geometry(g)
    {}

    template <typename Range>
    inline void apply(Range const& range)
    {
        typename geometry::point_type<Range>::type p;
        geometry::point_on_border(p, range);
        if ( !has_within && geometry::within(p, m_geometry) )
        {
            has_within = true;
        }
    }
};

template <typename FirstGeometry, typename SecondGeometry>
inline bool rings_containing(FirstGeometry const& geometry1,
                SecondGeometry const& geometry2)
{
    check_each_ring_for_within<FirstGeometry> checker(geometry1);
    geometry::detail::for_each_range(geometry2, checker);
    return checker.has_within;
}

template <typename Geometry1, typename Geometry2>
struct areal_areal
{
    static inline
    bool apply(Geometry1 const& geometry1, Geometry2 const& geometry2)
    {
        typedef detail::no_rescale_policy rescale_policy_type;
        typedef typename geometry::point_type<Geometry1>::type point_type;
        typedef detail::overlay::turn_info
            <
                point_type,
                typename segment_ratio_type<point_type, rescale_policy_type>::type
            > turn_info;

        std::deque<turn_info> turns;
        detail::touches::areal_interrupt_policy policy;
        rescale_policy_type robust_policy;
        boost::geometry::get_turns
                <
                    detail::overlay::do_reverse<geometry::point_order<Geometry1>::value>::value,
                    detail::overlay::do_reverse<geometry::point_order<Geometry2>::value>::value,
                    detail::overlay::assign_null_policy
                >(geometry1, geometry2, robust_policy, turns, policy);

        return policy.result()
            && ! geometry::detail::touches::rings_containing(geometry1, geometry2)
            && ! geometry::detail::touches::rings_containing(geometry2, geometry1);
    }
};

// P/*

struct use_point_in_geometry
{
    template <typename Point, typename Geometry>
    static inline bool apply(Point const& point, Geometry const& geometry)
    {
        return detail::within::point_in_geometry(point, geometry) == 0;
    }
};

}}
#endif // DOXYGEN_NO_DETAIL

#ifndef DOXYGEN_NO_DISPATCH
namespace dispatch {

// TODO: Since CastedTags are used is Reverse needed?

template
<
    typename Geometry1, typename Geometry2,
    typename Tag1 = typename tag<Geometry1>::type,
    typename Tag2 = typename tag<Geometry2>::type,
    typename CastedTag1 = typename tag_cast<Tag1, pointlike_tag, linear_tag, areal_tag>::type,
    typename CastedTag2 = typename tag_cast<Tag2, pointlike_tag, linear_tag, areal_tag>::type,
    bool Reverse = reverse_dispatch<Geometry1, Geometry2>::type::value
>
struct touches
    : not_implemented<Tag1, Tag2>
{};

// If reversal is needed, perform it
template
<
    typename Geometry1, typename Geometry2,
    typename Tag1, typename Tag2,
    typename CastedTag1, typename CastedTag2
>
struct touches<Geometry1, Geometry2, Tag1, Tag2, CastedTag1, CastedTag2, true>
    : touches<Geometry2, Geometry1, Tag2, Tag1, CastedTag2, CastedTag1, false>
{
    static inline bool apply(Geometry1 const& g1, Geometry2 const& g2)
    {
        return touches<Geometry2, Geometry1>::apply(g2, g1);
    }
};

// P/P

template <typename Geometry1, typename Geometry2, typename Tag1, typename Tag2>
struct touches<Geometry1, Geometry2, Tag1, Tag2, pointlike_tag, pointlike_tag, false>
{
    static inline bool apply(Geometry1 const& , Geometry2 const& )
    {
        return false;
    }
};

// P/*

template <typename Point, typename Geometry, typename Tag2, typename CastedTag2>
struct touches<Point, Geometry, point_tag, Tag2, pointlike_tag, CastedTag2, false>
    : detail::touches::use_point_in_geometry
{};

// TODO: support touches(MPt, Linear/Areal)

// Box/Box

template <typename Box1, typename Box2, typename CastedTag1, typename CastedTag2>
struct touches<Box1, Box2, box_tag, box_tag, CastedTag1, CastedTag2, false>
    : detail::touches::box_box
{};

template <typename Box1, typename Box2>
struct touches<Box1, Box2, box_tag, box_tag, areal_tag, areal_tag, false>
    : detail::touches::box_box
{};

// L/L

template <typename Linear1, typename Linear2, typename Tag1, typename Tag2>
struct touches<Linear1, Linear2, Tag1, Tag2, linear_tag, linear_tag, false>
    : detail::relate::relate_base
    <
        detail::relate::static_mask_touches_type,
        Linear1,
        Linear2
    >
{};

// L/A

template <typename Linear, typename Areal, typename Tag1, typename Tag2>
struct touches<Linear, Areal, Tag1, Tag2, linear_tag, areal_tag, false>
    : detail::relate::relate_base
    <
        detail::relate::static_mask_touches_type,
        Linear,
        Areal
    >
{};

// A/L
template <typename Linear, typename Areal, typename Tag1, typename Tag2>
struct touches<Linear, Areal, Tag1, Tag2, linear_tag, areal_tag, true>
    : detail::relate::relate_base
    <
        detail::relate::static_mask_touches_type,
        Areal,
        Linear
    >
{};

// A/A

template <typename Areal1, typename Areal2, typename Tag1, typename Tag2>
struct touches<Areal1, Areal2, Tag1, Tag2, areal_tag, areal_tag, false>
    : detail::touches::areal_areal<Areal1, Areal2>
{};

} // namespace dispatch
#endif // DOXYGEN_NO_DISPATCH


namespace resolve_variant {

template <typename Geometry1, typename Geometry2>
struct touches
{
    static bool apply(Geometry1 const& geometry1, Geometry2 const& geometry2)
    {
        concept::check<Geometry1 const>();
        concept::check<Geometry2 const>();

        return dispatch::touches<Geometry1, Geometry2>
                       ::apply(geometry1, geometry2);
    }
};

template <BOOST_VARIANT_ENUM_PARAMS(typename T), typename Geometry2>
struct touches<boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)>, Geometry2>
{
    struct visitor: boost::static_visitor<bool>
    {
        Geometry2 const& m_geometry2;

        visitor(Geometry2 const& geometry2): m_geometry2(geometry2) {}

        template <typename Geometry1>
        bool operator()(Geometry1 const& geometry1) const
        {
            return touches<Geometry1, Geometry2>::apply(geometry1, m_geometry2);
        }
    };

    static inline bool
    apply(boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)> const& geometry1,
          Geometry2 const& geometry2)
    {
        return boost::apply_visitor(visitor(geometry2), geometry1);
    }
};

template <typename Geometry1, BOOST_VARIANT_ENUM_PARAMS(typename T)>
struct touches<Geometry1, boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)> >
{
    struct visitor: boost::static_visitor<bool>
    {
        Geometry1 const& m_geometry1;

        visitor(Geometry1 const& geometry1): m_geometry1(geometry1) {}

        template <typename Geometry2>
        bool operator()(Geometry2 const& geometry2) const
        {
            return touches<Geometry1, Geometry2>::apply(m_geometry1, geometry2);
        }
    };

    static inline bool
    apply(Geometry1 const& geometry1,
          boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)> const& geometry2)
    {
        return boost::apply_visitor(visitor(geometry1), geometry2);
    }
};

template <BOOST_VARIANT_ENUM_PARAMS(typename T1),
          BOOST_VARIANT_ENUM_PARAMS(typename T2)>
struct touches<boost::variant<BOOST_VARIANT_ENUM_PARAMS(T1)>,
               boost::variant<BOOST_VARIANT_ENUM_PARAMS(T2)> >
{
    struct visitor: boost::static_visitor<bool>
    {
        template <typename Geometry1, typename Geometry2>
        bool operator()(Geometry1 const& geometry1,
                        Geometry2 const& geometry2) const
        {
            return touches<Geometry1, Geometry2>::apply(geometry1, geometry2);
        }
    };

    static inline bool
    apply(boost::variant<BOOST_VARIANT_ENUM_PARAMS(T1)> const& geometry1,
          boost::variant<BOOST_VARIANT_ENUM_PARAMS(T2)> const& geometry2)
    {
        return boost::apply_visitor(visitor(), geometry1, geometry2);
    }
};

template <typename Geometry>
struct self_touches
{
    static bool apply(Geometry const& geometry)
    {
        concept::check<Geometry const>();

        typedef detail::no_rescale_policy rescale_policy_type;
        typedef typename geometry::point_type<Geometry>::type point_type;
        typedef detail::overlay::turn_info
            <
                point_type,
                typename segment_ratio_type<point_type, rescale_policy_type>::type
            > turn_info;

        typedef detail::overlay::get_turn_info
        <
            detail::overlay::assign_null_policy
        > policy_type;

        std::deque<turn_info> turns;
        detail::touches::areal_interrupt_policy policy;
        rescale_policy_type robust_policy;
        detail::self_get_turn_points::get_turns
        <
            policy_type
        >::apply(geometry, robust_policy, turns, policy);

        return policy.result();
    }
};

template <BOOST_VARIANT_ENUM_PARAMS(typename T)>
struct self_touches<boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)> >
{
    struct visitor: boost::static_visitor<bool>
    {
        template <typename Geometry>
        bool operator()(Geometry const& geometry) const
        {
            return self_touches<Geometry>::apply(geometry);
        }
    };

    static inline bool
    apply(boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)> const& geometry)
    {
        return boost::apply_visitor(visitor(), geometry);
    }
};

} // namespace resolve_variant


/*!
\brief \brief_check{has at least one touching point (self-tangency)}
\note This function can be called for one geometry (self-tangency) and
    also for two geometries (touch)
\ingroup touches
\tparam Geometry \tparam_geometry
\param geometry \param_geometry
\return \return_check{is self-touching}

\qbk{distinguish,one geometry}
\qbk{[def __one_parameter__]}
\qbk{[include reference/algorithms/touches.qbk]}
*/
template <typename Geometry>
inline bool touches(Geometry const& geometry)
{
    return resolve_variant::self_touches<Geometry>::apply(geometry);
}


/*!
\brief \brief_check2{have at least one touching point (tangent - non overlapping)}
\ingroup touches
\tparam Geometry1 \tparam_geometry
\tparam Geometry2 \tparam_geometry
\param geometry1 \param_geometry
\param geometry2 \param_geometry
\return \return_check2{touch each other}

\qbk{distinguish,two geometries}
\qbk{[include reference/algorithms/touches.qbk]}
 */
template <typename Geometry1, typename Geometry2>
inline bool touches(Geometry1 const& geometry1, Geometry2 const& geometry2)
{
    return resolve_variant::touches<Geometry1, Geometry2>::apply(geometry1, geometry2);
}


}} // namespace boost::geometry

#endif // BOOST_GEOMETRY_ALGORITHMS_TOUCHES_HPP
