#include "Runtime/Character/CSteeringBehaviors.hpp"

#include "Runtime/CStateManager.hpp"
#include "Runtime/World/CPhysicsActor.hpp"

namespace urde {

zeus::CVector3f CSteeringBehaviors::Flee(const CPhysicsActor& actor, const zeus::CVector3f& v0) const {
  zeus::CVector3f actVec = actor.GetTranslation() - v0;
  if (actVec.canBeNormalized())
    return actVec.normalized();

  return actor.GetTransform().frontVector();
}

zeus::CVector3f CSteeringBehaviors::Seek(const CPhysicsActor& actor, const zeus::CVector3f& target) const {
  zeus::CVector3f posDiff = target - actor.GetTranslation();
  if (posDiff.canBeNormalized())
    return posDiff.normalized();

  return {};
}

zeus::CVector3f CSteeringBehaviors::Arrival(const CPhysicsActor& actor, const zeus::CVector3f& dest,
                                            float dampingRadius) const {
  zeus::CVector3f posDiff = dest - actor.GetTranslation();
  if (!posDiff.canBeNormalized())
    return {};

  if (posDiff.magSquared() < (dampingRadius * dampingRadius))
    dampingRadius = posDiff.magSquared() / (dampingRadius * dampingRadius);
  else
    dampingRadius = 1.f;

  return dampingRadius * posDiff.normalized();
}

zeus::CVector3f CSteeringBehaviors::Pursuit(const CPhysicsActor& actor, const zeus::CVector3f& v0,
                                            const zeus::CVector3f& v1) const {
  zeus::CVector3f target;
  if (!ProjectLinearIntersection(actor.GetTranslation(), actor.GetVelocity().magnitude(), v0, v1, target))
    target = v1 * 1.f + v0;
  return CSteeringBehaviors::Seek(actor, target);
}

zeus::CVector3f CSteeringBehaviors::Separation(const CPhysicsActor& actor, const zeus::CVector3f& pos,
                                               float separation) const {
  zeus::CVector3f posDiff = actor.GetTranslation() - pos;
  if (posDiff.magSquared() >= separation * separation)
    return {};

  if (!posDiff.canBeNormalized())
    return actor.GetTransform().frontVector();

  return (1.f - (posDiff.magSquared() / (separation * separation))) * posDiff.normalized();
}

zeus::CVector3f CSteeringBehaviors::Alignment(const CPhysicsActor& actor, rstl::reserved_vector<TUniqueId, 1024>& list,
                                              const CStateManager& mgr) const {
  zeus::CVector3f align;

  if (!list.empty()) {
    for (const TUniqueId& id : list)
      if (const CActor* act = static_cast<const CActor*>(mgr.GetObjectById(id)))
        align += act->GetTransform().frontVector();

    align *= zeus::CVector3f(1.f / float(list.size()));
  }

  float diff = zeus::CVector3f::getAngleDiff(actor.GetTransform().frontVector(), align);
  return align * (diff / M_PIF);
}

zeus::CVector3f CSteeringBehaviors::Cohesion(const CPhysicsActor& actor, rstl::reserved_vector<TUniqueId, 1024>& list,
                                             float dampingRadius, const CStateManager& mgr) const {
  zeus::CVector3f dest;
  if (!list.empty()) {
    for (const TUniqueId& id : list)
      if (const CActor* act = static_cast<const CActor*>(mgr.GetObjectById(id)))
        dest += act->GetTranslation();

    dest *= zeus::CVector3f(1.f / float(list.size()));
    return Arrival(actor, dest, dampingRadius);
  }
  return dest;
}

zeus::CVector2f CSteeringBehaviors::Flee2D(const CPhysicsActor& actor, const zeus::CVector2f& v0) const {
  zeus::CVector2f diffVec = actor.GetTranslation().toVec2f() - v0;
  if (diffVec.magSquared() > FLT_EPSILON)
    return diffVec.normalized();
  else
    return actor.GetTransform().basis[1].toVec2f();
}

zeus::CVector2f CSteeringBehaviors::Arrival2D(const CPhysicsActor& actor, const zeus::CVector2f& v0, float f1) const {
  zeus::CVector2f diffVec = v0 - actor.GetTranslation().toVec2f();
  if (diffVec.magSquared() > FLT_EPSILON)
    return diffVec.normalized();
  else
    return {};
}

bool CSteeringBehaviors::SolveQuadratic(float a, float b, float c, float& xPos, float& xNeg) {
  float numSq = b * b - 4.f * a * c;
  if (numSq < FLT_EPSILON || std::fabs(a) < FLT_EPSILON)
    return false;

  numSq = std::sqrt(numSq);
  float denom = 2.f * a;
  xPos = (-b + numSq) / denom;
  xNeg = (-b - numSq) / denom;
  return true;
}

bool CSteeringBehaviors::SolveCubic(const rstl::reserved_vector<float, 4>& in, rstl::reserved_vector<float, 4>& out) {
  if (in[3] != 0.f) {
    float f3 = 3.f * in[3];
    float f31 = in[2] / f3;
    float f4 = in[1] / f3 - f31 * f31;
    float f0 = (f31 * f4 - in[0]) / in[3];
    float f1 = 2.f * f31 * f31;
    f3 = f4 * f4 * f4;
    float f24 = -0.5f * (f31 * f1 - f0);
    f1 = f24 * f24 + f3;
    if (f1 < 0.f) {
      float f25 = std::acos(zeus::clamp(-1.f, f24 / std::sqrt(-f3), 1.f));
      f24 = 2.f * std::pow(-f3, 0.166667f);
      for (float f23 = 0.f; f23 < 2.01f; f23 += 1.f)
        out.push_back(std::cos((2.f * f23 * M_PIF + f25) / 3.f) * f24 - f31);
      if (out[1] < out[0])
        std::swap(out[1], out[0]);
      if (out[2] < out[1])
        std::swap(out[2], out[1]);
      if (out[1] < out[0])
        std::swap(out[1], out[0]);
    } else {
      float f30 = std::sqrt(f1);
      float f25 = std::pow(std::fabs(f24 + f30), 0.333333f);
      f1 = std::pow(std::fabs(f24 - f30), 0.333333f);
      f1 = (f24 - f30) > 0.f ? f1 : -f1;
      f25 = (f24 + f30) > 0.f ? f25 : -f25;
      out.push_back(f25 + f1 - f31);
    }
    for (float& f : out) {
      float f8 = (2.f * in[2] + 3.f * f * in[3]) * f + in[1];
      if (f8 != 0.f)
        f -= (((f * in[3] + in[2]) * f + in[1]) * f + in[0]) / f8;
    }
  } else if (in[2] != 0.f) {
    float f23 = 0.5f * in[1] / in[2];
    float f1 = f23 * f23 - (in[1] / in[2]);
    if (f1 >= 0.f) {
      f1 = std::sqrt(f1);
      out.push_back(-f23 - f1);
      out.push_back(-f23 + f1);
    }
  } else if (in[1] != 0.f) {
    out.push_back(-in[0] / in[1]);
  }
  return out.size() != 0;
}

bool CSteeringBehaviors::SolveQuartic(const rstl::reserved_vector<float, 5>& in, rstl::reserved_vector<float, 4>& out) {
  if (in[4] == 0.f) {
    rstl::reserved_vector<float, 4> newIn;
    newIn.push_back(in[0]);
    newIn.push_back(in[1]);
    newIn.push_back(in[2]);
    newIn.push_back(in[3]);
    return SolveCubic(newIn, out);
  } else {
    rstl::reserved_vector<float, 4> newIn;
    float f30 = in[3] / (4.f * in[4]);
    float f2 = in[1] / in[4];
    float f29 = f30 * (8.f * f30 * f30 - 2.f * in[2] / in[4]) + f2;
    float f31 = -6.f * f30 * f30 + (in[2] / in[4]);
    float f28 = f30 * (f30 * (-3.f * f30 * f30 + (in[2] / in[4])) - f2) + (in[0] / in[4]);
    newIn.push_back(4.f * f28 * f31 - f29 * f29);
    newIn.push_back(-8.f * f28);
    newIn.push_back(-4.f * f31);
    newIn.push_back(8.f);
    rstl::reserved_vector<float, 4> newOut;
    if (SolveCubic(newIn, newOut)) {
      float f26 = 2.f * newOut.back() - f31;
      f31 = std::sqrt(f26);
      float f1;
      if (f31 == 0.f) {
        f1 = newOut.back() * newOut.back() - f28;
        if (f1 < 0.f)
          return false;
        f1 = std::sqrt(f1);
      } else {
        f1 = f29 / (2.f * f31);
      }
      float f1b = f26 - (newOut.back() + f1) * 4.f;
      f26 = f26 - (newOut.back() - f1) * 4.f;
      if (f1b >= 0.f) {
        f1b = std::sqrt(f1b);
        out.push_back((f31 - f1b) * 0.5f - f30);
        out.push_back((f31 + f1b) * 0.5f - f30);
      }
      if (f26 >= 0.f) {
        f1b = std::sqrt(f26);
        out.push_back((-f31 - f1b) * 0.5f - f30);
        out.push_back((-f31 + f1b) * 0.5f - f30);
      }
      for (float& f : out) {
        float f10 = ((3.f * in[3] + 4.f * f * in[4]) * f + 2.f * in[2]) * f + in[1];
        if (f10 != 0.f)
          f -= ((((f * in[4] + in[3]) * f + in[2]) * f + in[1]) * f + in[0]) / f10;
      }
      if (out.size() > 2) {
        if (out[2] < out[0])
          std::swap(out[2], out[0]);
        if (out[3] < out[1])
          std::swap(out[3], out[1]);
        if (out[1] < out[0])
          std::swap(out[1], out[0]);
        if (out[3] < out[2])
          std::swap(out[3], out[2]);
        if (out[2] < out[1])
          std::swap(out[2], out[1]);
      }
    }
    return out.size() != 0;
  }
}

bool CSteeringBehaviors::ProjectLinearIntersection(const zeus::CVector3f& v0, float f1, const zeus::CVector3f& v1,
                                                   const zeus::CVector3f& v2, zeus::CVector3f& v3) {
  zeus::CVector3f posDiff = v1 - v0;
  float xPos, xNeg;
  if (SolveQuadratic(v2.magSquared() - f1 * f1, posDiff.dot(v2) * 2.f, posDiff.magSquared(), xPos, xNeg) &&
      xNeg > 0.f) {
    v3 = v2 * xNeg + v1;
    return true;
  }
  return false;
}

bool CSteeringBehaviors::ProjectLinearIntersection(const zeus::CVector3f& v0, float f1, const zeus::CVector3f& v1,
                                                   const zeus::CVector3f& v2, const zeus::CVector3f& v3,
                                                   zeus::CVector3f& v4) {
  rstl::reserved_vector<float, 5> newIn;
  rstl::reserved_vector<float, 4> newOut;
  zeus::CVector3f f7 = v1 - v0;
  newIn.push_back(f7.magSquared());
  newIn.push_back(f7.dot(v2) * 2.f);
  newIn.push_back(f7.dot(v3) + v2.magSquared() - f1 * f1);
  newIn.push_back(v2.dot(v3));
  newIn.push_back(v3.magSquared() * 0.25f);
  bool ret = false;
  if (SolveQuartic(newIn, newOut))
    for (float& f : newOut)
      if (f > 0.f) {
        ret = true;
        v4 = v1 + v2 * f + 0.5f * f * f * v3;
      }
  return ret;
}

bool CSteeringBehaviors::ProjectOrbitalIntersection(const zeus::CVector3f& v0, float f1, float f2,
                                                    const zeus::CVector3f& v1, const zeus::CVector3f& v2,
                                                    const zeus::CVector3f& v3, zeus::CVector3f& v4) {
  if (f1 > 0.f) {
    if (v2.canBeNormalized()) {
      zeus::CVector3f _12c = (v1 - v3).toVec2f();
      if (_12c.canBeNormalized()) {
        zeus::CVector3f f25 = v1;
        zeus::CVector3f f22 = v2;
        float f17 = (f25 - v0).magnitude() / f1 - 0.f;
        float f18 = FLT_MAX;
        zeus::CVector3f _150 = _12c.normalized();
        float f26 = _150.dot(f22);
        float f27 = _150.cross(zeus::skUp).dot(f22);
        for (float f19 = 0.f; f17 < f18 && f19 < 4.f;) {
          if (zeus::close_enough(f17, f2) || f17 < 0.f) {
            v4 = f25;
            return true;
          }
          f25 += f2 * f22;
          f18 = f17;
          _12c = (f25 - v3).toVec2f();
          if (!_12c.canBeNormalized())
            break;
          zeus::CVector3f _168 = _12c.normalized();
          f22 = _168.cross(zeus::skUp) * f27 + f26 * _168;
          f19 += f2;
          f17 = (f25 - v0).magnitude() / f1 - f19;
        }
      } else {
        return ProjectLinearIntersection(v0, f1, v1, v2, v4);
      }
    } else {
      v4 = v1;
      return true;
    }
  }
  return false;
}

bool CSteeringBehaviors::ProjectOrbitalIntersection(const zeus::CVector3f& v0, float f1, float f2,
                                                    const zeus::CVector3f& v1, const zeus::CVector3f& v2,
                                                    const zeus::CVector3f& v3, const zeus::CVector3f& v4,
                                                    zeus::CVector3f& v5) {
  if (f1 > 0.f) {
    zeus::CVector3f _12c = (v1 - v4).toVec2f();
    if (v2.canBeNormalized() && _12c.canBeNormalized()) {
      zeus::CVector3f f24 = v1;
      zeus::CVector3f f21 = v2;
      float f16 = (f24 - v0).magnitude() / f1 - 0.f;
      float f17 = FLT_MAX;
      zeus::CVector3f _150 = _12c.normalized();
      float f25 = _150.dot(f21);
      float f26 = _150.cross(zeus::skUp).dot(f21);
      for (float f18 = 0.f; f16 < f17 && f18 < 4.f;) {
        if (zeus::close_enough(f16, f2) || f16 < 0.f) {
          v5 = f24;
          return true;
        }
        f24 += f2 * f21;
        f17 = f16;
        f18 += f2;
        f16 = (f24 - v0).magnitude() / f1 - f18;
        _12c = (f24 - v4).toVec2f();
        if (!_12c.canBeNormalized())
          break;
        zeus::CVector3f _168 = _12c.normalized();
        f21 = _168.cross(zeus::skUp) * f26 + f25 * _168;
      }
    } else {
      return ProjectLinearIntersection(v0, f1, v1, v2, v3, v5);
    }
  }
  return false;
}

zeus::CVector3f CSteeringBehaviors::ProjectOrbitalPosition(const zeus::CVector3f& pos, const zeus::CVector3f& vel,
                                                           const zeus::CVector3f& orbitPoint, float dt,
                                                           float preThinkDt) {
  zeus::CVector3f usePos = pos;
  if (vel.canBeNormalized()) {
    zeus::CVector3f pointToPos = pos - orbitPoint;
    pointToPos.z() = 0.f;
    if (pointToPos.canBeNormalized()) {
      zeus::CVector3f useVel = vel;
      pointToPos.normalize();
      float f29 = pointToPos.dot(useVel);
      float f30 = pointToPos.cross(zeus::skUp).dot(useVel);
      for (float curDt = 0.f; curDt < dt;) {
        usePos += preThinkDt * useVel;
        zeus::CVector3f usePointToPos = usePos - orbitPoint;
        usePointToPos.z() = 0.f;
        if (usePointToPos.canBeNormalized()) {
          usePointToPos.normalize();
          useVel = usePointToPos.cross(zeus::skUp) * f30 + usePointToPos * f29;
        }
        curDt += std::min(dt - curDt, preThinkDt);
      }
    }
  }
  return usePos;
}

} // namespace urde