#include "ext/LinearPotential.h"

#include <tmathutil.h></tmathutil.h>

#include <algorithm></algorithm>

#include "tstroke.h"

using namespace std;

//-----------------------------------------------------------------------------

void ToonzExt::LinearPotential::setParameters_(const TStroke *ref, double par,

                                               double al) {

  ref_          = ref;

  par_          = par;

  actionLength_ = al;

  strokeLength_  = ref->getLength();

  lengthAtParam_ = ref->getLength(par);

  // lunghezza dal pto di click all'inizio della curva

  leftFactor_ = lengthAtParam_;

  // lunghezza dal pto di click alla fine

  rightFactor_ = strokeLength_ - lengthAtParam_;

  // considero come intervallo di mapping [-range,range].

  //  4 ha come valore c.a. 10exp-6

  //  cioé sposterei un pixel su un movimento di un milione di pixel

  range_ = 2.8;

}

//-----------------------------------------------------------------------------

ToonzExt::LinearPotential::~LinearPotential() {}

//-----------------------------------------------------------------------------

double ToonzExt::LinearPotential::value_(double value2test) const {

  assert(0.0 <= value2test && value2test <= 1.0);

  return this->compute_value(value2test);

}

//-----------------------------------------------------------------------------

// normalization of parameter in range interval

double ToonzExt::LinearPotential::compute_shape(double value2test) const {

  double x                       = ref_->getLength(value2test);

  double shape                   = this->actionLength_ * 0.5;

  if (isAlmostZero(shape)) shape = 1.0;

  x                              = ((x - lengthAtParam_) * range_) / shape;

  return x;

}

//-----------------------------------------------------------------------------

double ToonzExt::LinearPotential::compute_value(double value2test) const {

  // use

  //

  //  1-x

  //

  double x   = 0.0;

  double res = 0.0;

  // length  at parameter

  x = ref_->getLength(value2test);

  double tmp_al = actionLength_ * 0.5;

  if (isAlmostZero(par_) || areAlmostEqual(par_, 1.0)) tmp_al = actionLength_;

  // this is ckecked from wrapper class

  assert(tmp_al != 0.0);

  // compute correct parameter considering offset

  // try to have a square curve like shape

  //

  //  m = x

  //

  if (leftFactor_ == 0.0)

    x = 1.0 - x / tmp_al;

  else if (rightFactor_ == 0.0)

    x = (x - (strokeLength_ - tmp_al)) / tmp_al;

  else {

    if (x <= lengthAtParam_ && ((lengthAtParam_ - x) <= leftFactor_))

      x = (x - (lengthAtParam_ - leftFactor_)) / leftFactor_;

    else if (x > lengthAtParam_ && ((x - lengthAtParam_) < rightFactor_))

      x = (rightFactor_ - (x - lengthAtParam_)) / rightFactor_;

    else

      x = -1;

  }

  if (x < 0.0) return 0.0;

  // assert( 0.0 <= x &&

  //  x <= 1.0 + TConsts::epsilon );

  res = x;

  return res;

}

//-----------------------------------------------------------------------------

ToonzExt::Potential *ToonzExt::LinearPotential::clone() {

  return new LinearPotential;

}

//-----------------------------------------------------------------------------

//  End Of File

//-----------------------------------------------------------------------------