/*
 * Copyright (C) 2016+     AzerothCore <www.azerothcore.org>, released under GNU GPL v2 license: https://github.com/azerothcore/azerothcore-wotlk/blob/master/LICENSE-GPL2
 * Copyright (C) 2008-2016 TrinityCore <http://www.trinitycore.org/>
 * Copyright (C) 2005-2009 MaNGOS <http://getmangos.com/>
 */

namespace Movement
{
    template<typename length_type> void Spline<length_type>::evaluate_percent( float t, Vector3& c ) const
    {
        index_type Index;
        float u;
        computeIndex(t, Index, u);
        evaluate_percent(Index, u, c);
    }

    template<typename length_type> void Spline<length_type>::evaluate_derivative(float t, Vector3& hermite) const
    {
        index_type Index;
        float u;
        computeIndex(t, Index, u);
        evaluate_derivative(Index, u, hermite);
    }

    template<typename length_type> SplineBase::index_type Spline<length_type>::computeIndexInBounds(length_type length_) const
    {
        // Temporary disabled: causes infinite loop with t = 1.f
        /*
            index_type hi = index_hi;
            index_type lo = index_lo;

            index_type i = lo + (float)(hi - lo) * t;

            while ((lengths[i] > length) || (lengths[i + 1] <= length))
            {
                if (lengths[i] > length)
                    hi = i - 1; // too big
                else if (lengths[i + 1] <= length)
                    lo = i + 1; // too small

                i = (hi + lo) / 2;
            }*/

        index_type i = index_lo;
        index_type N = index_hi;
        while (i + 1 < N && lengths[i + 1] < length_)
            ++i;

        return i;
    }

    template<typename length_type> void Spline<length_type>::computeIndex(float t, index_type& index, float& u) const
    {
        ASSERT(t >= 0.f && t <= 1.f);
        length_type length_ = t * length();
        index = computeIndexInBounds(length_);
        ASSERT(index < index_hi);
        u = (length_ - length(index)) / (float)length(index, index + 1);
    }

    template<typename length_type> SplineBase::index_type Spline<length_type>::computeIndexInBounds( float t ) const
    {
        ASSERT(t >= 0.f && t <= 1.f);
        return computeIndexInBounds(t * length());
    }

    template<typename length_type> void Spline<length_type>::initLengths()
    {
        index_type i = index_lo;
        length_type length = 0;
        lengths.resize(index_hi + 1);
        while (i < index_hi)
        {
            length += SegLength(i);
            lengths[++i] = length;
        }
    }

    template<typename length_type> void Spline<length_type>::clear()
    {
        SplineBase::clear();
        lengths.clear();
    }

}