#include <tools/modifiers/modifierline.h>


//*****************************************************************************************
//    TModifierLine implementation
//*****************************************************************************************


static inline void calcFixedAngle(const TTrackPoint &p0, TTrackPoint &p1) {
  TPointD p = p1.position - p0.position;
  double l = sqrt(p.x*p.x + p.y*p.y);
  if (l < TConsts::epsilon) {
    p = TPointD();
  } else {
    double a = atan2(p.y, p.x);
    a = round(a*4/M_PI)*M_PI/4;
    p.x = cos(a)*l;
    p.y = sin(a)*l;
  }
  p1.position = p0.position + p;
}


TTrackPoint TModifierLine::Modifier::calcPoint(double originalIndex) {
  if (original.empty()) return TTrackPoint();
  if (original.size() < 2) return original.front();
  TTrackPoint p0 = original.front();
  TTrackPoint p1 = original.back();
  if (fixAngle) calcFixedAngle(p0, p1);
  return TTrack::interpolationLinear(p0, p1, originalIndex/(original.size() - 1));
}

void
TModifierLine::modifyTrack(
  const TTrack &track,
  const TInputSavePoint::Holder &savePoint,
  TTrackList &outTracks )
{
  if (!track.handler) {
    track.handler = new TTrackHandler(track);
    Modifier *modifier = new Modifier(*track.handler);
    modifier->savePoint = savePoint;
    track.handler->tracks.push_back( new TTrack(modifier) );
  }

  if (!track.changed())
    return;
  if (track.handler->tracks.empty())
    return;
  
  TTrack &subTrack = *track.handler->tracks.front();
  Modifier* modifier = dynamic_cast<Modifier*>(subTrack.modifier.getPointer());
  if (!modifier)
    { track.resetChanges(); return; }
  
  bool fixAngle = track.getKeyState(track.back()).isPressed(TKey::shift);
  outTracks.push_back(track.handler->tracks.front());

  int i1 = track.size();
  int i0 = i1 - track.pointsAdded;
  double maxPressure = modifier->maxPressure;
  if (track.pointsRemoved)
    { maxPressure = 0; i0 = 0; }
  for(int i = i0; i < i1; ++i) {
    double p = track[i].pressure;
    if (maxPressure < p) maxPressure = p;
  }
  modifier->maxPressure = maxPressure;
  modifier->fixAngle = fixAngle;
  if (track.finished())
    modifier->savePoint.reset();

  subTrack.truncate(0);
  
  if (track.size() > 0) {
    TTrackPoint p = track.front();
    p.originalIndex = 0;
    p.pressure = maxPressure;
    p.tilt = TPointD();
    subTrack.push_back(p);
  }
  
  if (track.size() > 1) {
    TTrackPoint p = track.back();
    p.originalIndex = track.size() - 1;
    p.pressure = maxPressure;
    p.tilt = TPointD();
    if (fixAngle) calcFixedAngle(subTrack.front(), p);
    subTrack.push_back(p);
  }
  
  track.resetChanges();
}