#include <tools/modifiers/modifiertest.h>

// std includes

#include <cmath>

//*****************************************************************************************

//    TModifierTest::Modifier implementation

//*****************************************************************************************

TModifierTest::Modifier::Modifier(

  TTrackHandler &handler,

  double angle,

  double radius,

  double speed

):

  TTrackModifier(handler),

  angle(angle),

  radius(radius),

  speed(speed)

{ }

TTrackPoint

TModifierTest::Modifier::calcPoint(double originalIndex) {

  TTrackPoint p = TTrackModifier::calcPoint(originalIndex);

  if (p.length > TConsts::epsilon) {

    double frac;

    int i0 = original.floorIndex(originalIndex, &frac);

    int i1 = original.ceilIndex(originalIndex);

    if (i0 < 0) return p;

    if (Handler *handler = dynamic_cast<Handler*>(&this->handler)) {

      double angle = this->angle + speed*TTrack::interpolationLinear(

        handler->angles[i0], handler->angles[i1], frac);

      double radius = 2.0*this->radius*p.pressure;

      double s = sin(angle);

      double c = cos(angle);

      TPointD tangent = original.calcTangent(originalIndex, fabs(2.0*this->radius/speed));

      p.position.x -= tangent.y*s*radius;

      p.position.y += tangent.x*s*radius;

      p.pressure   *= 1.0 - 0.5*c;

    }

  } else {

    p.pressure = 0.0;

  }

  return p;

}

//*****************************************************************************************

//    TModifierTest implementation

//*****************************************************************************************

TModifierTest::TModifierTest(int count, double radius):

  count(count),

  radius(radius)

{ }

void

TModifierTest::modifyTrack(

  const TTrack &track,

  const TInputSavePoint::Holder &savePoint,

  TTrackList &outTracks )

{

  const double segmentSize = 2.0*M_PI/10.0;

  if (!track.handler) {

    if (track.getKeyState(track.front().time).isPressed(TKey(Qt::Key_Alt))) {

      // TModifierTest::Handler for spiro

      track.handler = new Handler(track);

      for(int i = 0; i < count; ++i)

        track.handler->tracks.push_back(

          new TTrack(

            new Modifier(

              *track.handler,

              i*2.0*M_PI/(double)count,

              radius,

              0.25 )));

    }

  }

  Handler *handler = dynamic_cast<Handler*>(track.handler.getPointer());

  if (!handler) {

    TInputModifier::modifyTrack(track, savePoint, outTracks);

    return;

  }

  outTracks.insert(

    outTracks.end(),

    track.handler->tracks.begin(),

    track.handler->tracks.end() );

  if (!track.changed())

    return;

  int start = track.size() - track.pointsAdded;

  if (start < 0) start = 0;

  // remove angles

  double lastAngle = start < (int)handler->angles.size() ? handler->angles[start]

                   : handler->angles.empty() ? 0.0

                   : handler->angles.back();

  handler->angles.resize(start, lastAngle);

  // add angles

  for(int i = start; i < track.size(); ++i) {

    if (i > 0) {

      double dl = track[i].length - track[i-1].length;

      double da = track[i].pressure > TConsts::epsilon

                ? dl/(radius*track[i].pressure) : 0.0;

      handler->angles.push_back(handler->angles[i-1] + da);

    } else {

      handler->angles.push_back(0.0);

    }

  }

  // process sub-tracks

  for(TTrackList::const_iterator ti = handler->tracks.begin(); ti != handler->tracks.end(); ++ti) {

    TTrack &subTrack = **ti;

    double currentSegmentSize = segmentSize;

    if (const Modifier *modifier = dynamic_cast<const Modifier*>(subTrack.modifier.getPointer()))

      if (fabs(modifier->speed) > TConsts::epsilon)

        currentSegmentSize = segmentSize/fabs(modifier->speed);

    // remove points

    int subStart = subTrack.floorIndex(subTrack.indexByOriginalIndex(start-1)) + 1;

    subTrack.truncate(subStart);

    // add points

    for(int i = start; i < track.size(); ++i) {

      if (i > 0) {

        double prevAngle = handler->angles[i-1];

        double nextAngle = handler->angles[i];

        if (fabs(nextAngle - prevAngle) > 1.5*currentSegmentSize) {

          double step = currentSegmentSize/fabs(nextAngle - prevAngle);

          double end = 1.0 - 0.5*step;

          for(double frac = step; frac < end; frac += step)

            subTrack.push_back( subTrack.modifier->calcPoint((double)i - 1.0 + frac) );

        }

      }

      subTrack.push_back( subTrack.modifier->calcPoint(i) );

    }

  }

  track.resetChanges();

}