#include "CPathFindSearch.hpp"

namespace urde
{

bool CPathFindSearch::SegmentOver(const zeus::CVector3f& p1) const
{
    if (x4_waypoints.size() > 1 && xc8_curWaypoint < x4_waypoints.size() - 1)
    {
        const zeus::CVector3f& wp0 = x4_waypoints[xc8_curWaypoint];
        const zeus::CVector3f& wp1 = x4_waypoints[xc8_curWaypoint + 1];
        const zeus::CVector3f& wp2 = x4_waypoints[std::min(u32(x4_waypoints.size()) - 1, xc8_curWaypoint + 2)];
        return (p1 - wp1).dot(wp2 - wp0) >= 0.f;
    }
    return true;
}

void CPathFindSearch::GetSplinePoint(zeus::CVector3f& pOut, const zeus::CVector3f& p1, u32 wpIdx) const
{
    if (x4_waypoints.size() > 1 && wpIdx < x4_waypoints.size() - 1)
    {
        zeus::CVector3f a = (wpIdx == 0) ? x4_waypoints[0] * 2.f - x4_waypoints[1] : x4_waypoints[wpIdx-1];
        const zeus::CVector3f& b = x4_waypoints[wpIdx];
        const zeus::CVector3f& c = x4_waypoints[wpIdx+1];
        zeus::CVector3f d = (wpIdx + 2 >= x4_waypoints.size()) ?
            x4_waypoints[x4_waypoints.size()-1] * 2.f - x4_waypoints[x4_waypoints.size()-2] : x4_waypoints[wpIdx+2];
        zeus::CVector3f delta = c - b;
        if (delta.isMagnitudeSafe())
            pOut = zeus::getCatmullRomSplinePoint(a, b, c, d, (p1 - b).dot(delta) / delta.magSquared());
        else
            pOut = b;
    }
}

void CPathFindSearch::GetSplinePoint(zeus::CVector3f& pOut, const zeus::CVector3f& p1) const
{
    GetSplinePoint(pOut, p1, xc8_curWaypoint);
}

void CPathFindSearch::GetSplinePointWithLookahead(zeus::CVector3f& pOut, const zeus::CVector3f& p1,
                                                  u32 wpIdx, float lookahead) const
{
    if (x4_waypoints.size() > 1 && wpIdx < x4_waypoints.size() - 1)
    {
        const zeus::CVector3f& wp0 = x4_waypoints[wpIdx];
        const zeus::CVector3f& wp1 = x4_waypoints[wpIdx+1];
        zeus::CVector3f delta = wp1 - wp0;
        if (delta.isMagnitudeSafe())
        {
            float deltaMag = delta.magnitude();
            delta = delta * (1.f / deltaMag);
            float bToPtProj = (p1 - wp0).dot(delta);
            if (bToPtProj + lookahead <= deltaMag)
                GetSplinePoint(pOut, delta * lookahead + p1, wpIdx);
            else if (wpIdx < x4_waypoints.size() - 2)
                GetSplinePointWithLookahead(pOut, wp1, wpIdx + 1, lookahead - (deltaMag - bToPtProj));
            else
                pOut = delta * (lookahead - (deltaMag - bToPtProj)) + wp1;
        }
        else
        {
            pOut = wp1;
        }
    }
}

void CPathFindSearch::GetSplinePointWithLookahead(zeus::CVector3f& pOut, const zeus::CVector3f& p1,
                                                  float lookahead) const
{
    GetSplinePointWithLookahead(pOut, p1, xc8_curWaypoint, lookahead);
}

}