/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * Copyright 2018 Danny Robson <danny@nerdcruft.net>
 */

#pragma once

#include "../point.hpp"
#include "../vector.hpp"

namespace util::geom {
    // an line of infinite extent that passes though 'base'.
    //
    // direction should be normalised
    template <size_t S, typename T>
    struct line {
        line () = default;
        line (util::point<S,T> a, util::point<S,T> b):
            line (a, normalised (b - a))
        { ; }

        line (util::point<S,T> _base, util::vector<S,T> _direction):
            base (_base),
            direction (_direction)
        {
            CHECK (is_normalised (direction));
        }

        util::point<S,T> base;
        util::vector<S,T> direction;
    };

    using line2f = line<2,float>;
    using line3f = line<3,float>;


    template <size_t S, typename T>
    T
    distance2 (line<S,T> l, point<S,T> p)
    {
        const auto t = dot (p - l.base, l.direction);
        return distance2 (p, l.base + l.direction * t);
    }


    template <size_t S, typename T>
    T
    distance (line<S,T> l, point<S,T> p)
    {
        return std::sqrt (distance2 (l, p));
    }
};