// Copyright (C)  2003  Dominique Devriese <devriese@kde.org>

// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
// 02110-1301, USA.

#include "circle_imp.h"

#include "bogus_imp.h"
#include "point_imp.h"

#include "../misc/kigtransform.h"
#include "../misc/kigpainter.h"
#include "../misc/equationstring.h"
#include "../misc/coordinate_system.h"

#include "../kig/kig_document.h"
#include "../kig/kig_view.h"

#include <math.h>

CircleImp::CircleImp( const Coordinate& center, double radius )
  : mcenter( center ), mradius( radius )
{
}

CircleImp::~CircleImp()
{
}

ObjectImp* CircleImp::transform( const Transformation& t ) const
{
  if ( t.isHomothetic() )
  {
    Coordinate nc = t.apply( mcenter );
    double nr = t.apply( mradius );
    if ( nc.valid() )
      return new CircleImp( nc, nr );
    else return new InvalidImp;
  }
  else
  {
    // domi: i should return a ConicImp here, but i don't know how to
    // calculate it..
    return Parent::transform( t );
  };
}

void CircleImp::draw( KigPainter& p ) const
{
  p.drawCircle( mcenter, mradius );
}

bool CircleImp::contains( const Coordinate& p, int width, const KigWidget& w ) const
{
  return fabs((mcenter - p).length() - mradius) <= w.screenInfo().normalMiss( width );
}

bool CircleImp::inRect( const Rect& r, int width, const KigWidget& w ) const
{
  // first we check if the rect contains at least one of the
  // north/south/east/west points of the circle
  if ( r.contains( mcenter + Coordinate( 0, -mradius ) ) ) return true;
  if ( r.contains( mcenter + Coordinate( mradius, 0 ) ) ) return true;
  if ( r.contains( mcenter + Coordinate( 0, mradius ) ) ) return true;
  if ( r.contains( mcenter + Coordinate( -mradius, 0 ) ) ) return true;

  // we allow a miss of some pixels ..
  double miss = w.screenInfo().normalMiss( width );
  double bigradius = mradius + miss;
  bigradius *= bigradius;
  double smallradius = mradius - miss;
  smallradius *= smallradius;

  const int in = -1;
  const int undecided = 0;
  const int out = 1;

  int inorout = undecided;

  Coordinate coords[4];
  coords[0] = r.topLeft();
  coords[1] = r.topRight();
  coords[2] = r.bottomRight();
  coords[3] = r.bottomLeft();

  // we check if the corners of the rect are either
  for ( Coordinate* i = coords; i < coords + 4; ++i )
  {
    double t = ( *i - mcenter ).squareLength();
    if ( t >= bigradius )
    {
      if ( inorout == in ) return true;
      inorout = out;
    }
    else if ( t <= smallradius )
    {
      if ( inorout == out ) return true;
      inorout = in;
    }
  }
  return inorout == undecided;
}

bool CircleImp::valid() const
{
  return true;
}

int CircleImp::numberOfProperties() const
{
  // We _intentionally_ do not use the Conic properties..
  return CurveImp::numberOfProperties() + 7;
}

const QByteArrayList CircleImp::propertiesInternalNames() const
{
  QByteArrayList l = CurveImp::propertiesInternalNames();
  l << "surface";
  l << "circumference";
  l << "radius";
  l << "center";
  l << "cartesian-equation";
  l << "simply-cartesian-equation";
  l << "polar-equation";
  assert( l.size() == CircleImp::numberOfProperties() );
  return l;
}

const QByteArrayList CircleImp::properties() const
{
  QByteArrayList l = CurveImp::properties();
  l << I18N_NOOP( "Surface" );
  l << I18N_NOOP( "Circumference" );
  l << I18N_NOOP( "Radius" );
  l << I18N_NOOP( "Center" );
  l << I18N_NOOP( "Expanded Cartesian Equation" );
  l << I18N_NOOP( "Cartesian Equation" );
  l << I18N_NOOP( "Polar Equation" );
  assert( l.size() == CircleImp::numberOfProperties() );
  return l;
}

const ObjectImpType* CircleImp::impRequirementForProperty( int which ) const
{
  if ( which < CurveImp::numberOfProperties() )
    return CurveImp::impRequirementForProperty( which );
  else return CircleImp::stype();
}

const char* CircleImp::iconForProperty( int which ) const
{
  assert( which < CircleImp::numberOfProperties() );
  if ( which < CurveImp::numberOfProperties() )
    return CurveImp::iconForProperty( which );
  else if ( which == CurveImp::numberOfProperties() )
    return "areaCircle"; // surface
  else if ( which == CurveImp::numberOfProperties() + 1 )
    return "circumference"; // circumference
  else if ( which == CurveImp::numberOfProperties() + 2 )
    return "";  //radius
  else if ( which == CurveImp::numberOfProperties() + 3 )
    return "baseCircle"; // circle center
  else if ( which == CurveImp::numberOfProperties() + 4 )
    return "kig_text"; // cartesian equation
  else if ( which == CurveImp::numberOfProperties() + 5 )
    return "kig_text"; // simply cartesian equation
  else if ( which == CurveImp::numberOfProperties() + 6 )
    return "kig_text"; // polar equation
  else assert( false );
  return "";
}

ObjectImp* CircleImp::property( int which, const KigDocument& w ) const
{
  assert( which < CircleImp::numberOfProperties() );
  if ( which < CurveImp::numberOfProperties() )
    return CurveImp::property( which, w );
  if ( which == CurveImp::numberOfProperties() )
    return new DoubleImp( surface() );
  else if ( which == CurveImp::numberOfProperties() + 1 )
    return new DoubleImp( circumference() );
  else if ( which == CurveImp::numberOfProperties() + 2 )
    return new DoubleImp( radius() );
  else if ( which == CurveImp::numberOfProperties() + 3 )
    return new PointImp( center() );
  else if ( which == CurveImp::numberOfProperties() + 4 )
    return new StringImp( cartesianEquationString( w ) );
  else if ( which == CurveImp::numberOfProperties() + 5 )
    return new StringImp( simplyCartesianEquationString( w ) );
  else if ( which == CurveImp::numberOfProperties() + 6 )
    return new StringImp( polarEquationString( w ) );
  else assert( false );
  return new InvalidImp;
}

const Coordinate CircleImp::center() const
{
  return mcenter;
}

double CircleImp::radius() const
{
  return mradius;
}

double CircleImp::surface() const
{
  return M_PI * squareRadius();
}

double CircleImp::squareRadius() const
{
  return mradius * mradius;
}

double CircleImp::circumference() const
{
  return 2 * M_PI * radius();
}

QString CircleImp::polarEquationString( const KigDocument& w ) const
{
  ConicPolarData data = polarData();
  QString ret = ki18n( "rho = %1   [centered at %2]" )
                     .subs( data.pdimen, 0, 'g', 3 )
                     .subs( w.coordinateSystem().fromScreen( data.focus1, w ) )
                     .toString();
  return ret;
}

QString CircleImp::cartesianEquationString( const KigDocument& ) const
{
//  QString ret = i18n( "x² + y² + %1 x + %2 y + %3 = 0" );
  ConicCartesianData data = cartesianData();
  EquationString ret = EquationString( "" );
  bool needsign = false;
  ret.addTerm( 1., ret.x2(), needsign );
  ret.addTerm( 1., ret.y2(), needsign );
  ret.addTerm( data.coeffs[3], ret.x(), needsign );
  ret.addTerm( data.coeffs[4], ret.y(), needsign );
  ret.addTerm( data.coeffs[5], "", needsign );
  ret.append( " = 0" );
//  ret = ret.arg( data.coeffs[3], 0, 'g', 3 );
//  ret = ret.arg( data.coeffs[4], 0, 'g', 3 );
//  ret = ret.arg( data.coeffs[5], 0, 'g', 3 );
  return ret;
}

QString CircleImp::simplyCartesianEquationString( const KigDocument& ) const
{
  EquationString ret = EquationString( "( x" );
  bool needsign = true;
  ret.addTerm( -mcenter.x, "", needsign );
  ret.append( QString::fromUtf8( " )² + ( y" ) );
  ret.addTerm( -mcenter.y, "", needsign );
  ret.append( QString::fromUtf8( " )² = " ) );
  needsign = false;
  ret.addTerm( mradius*mradius, "", needsign );
  ret.prettify();

//  QString ret = i18n( "( x - %1 )² + ( y - %2 )² = %3" );
//  ret = ret.arg( mcenter.x, 0, 'g', 3 );
//  ret = ret.arg( mcenter.y, 0, 'g', 3 );
//  ret = ret.arg( mradius * mradius, 0, 'g', 3 );
  return ret;
}

Coordinate CircleImp::focus1() const
{
  return center();
}

Coordinate CircleImp::focus2() const
{
  return center();
}

int CircleImp::conicType() const
{
  return 1;
}

const ConicCartesianData CircleImp::cartesianData() const
{
  Coordinate c = center();
  double sqr = squareRadius();
  ConicCartesianData data(
    1.0, 1.0, 0.0, -2*c.x, -2*c.y,
    c.x*c.x + c.y*c.y - sqr );
  return data;
}

const ConicPolarData CircleImp::polarData() const
{
  return ConicPolarData( center(), radius(), 0, 0 );
}

CircleImp* CircleImp::copy() const
{
  return new CircleImp( mcenter, mradius );
}

double CircleImp::getParam( const Coordinate& point, const KigDocument& ) const
{
  Coordinate tmp = point - mcenter;
  double ret = atan2(tmp.y, tmp.x) / ( 2 * M_PI );
  if ( ret > 0 ) return ret;
  else return ret + 1;
}

const Coordinate CircleImp::getPoint( double p, const KigDocument& ) const
{
  return mcenter + Coordinate (cos(p * 2 * M_PI), sin(p * 2 * M_PI)) * mradius;
}

void CircleImp::visit( ObjectImpVisitor* vtor ) const
{
  vtor->visit( this );
}

bool CircleImp::equals( const ObjectImp& rhs ) const
{
  return rhs.inherits( CircleImp::stype() ) &&
    static_cast<const CircleImp&>( rhs ).center() == center() &&
    static_cast<const CircleImp&>( rhs ).radius() == radius();
}

const ObjectImpType* CircleImp::stype()
{
  static const ObjectImpType t(
    Parent::stype(), "circle",
    I18N_NOOP( "circle" ),
    I18N_NOOP( "Select this circle" ),
    I18N_NOOP( "Select circle %1" ),
    I18N_NOOP( "Remove a Circle" ),
    I18N_NOOP( "Add a Circle" ),
    I18N_NOOP( "Move a Circle" ),
    I18N_NOOP( "Attach to this circle" ),
    I18N_NOOP( "Show a Circle" ),
    I18N_NOOP( "Hide a Circle" )
    );
  return &t;
}

const ObjectImpType* CircleImp::type() const
{
  return CircleImp::stype();
}

bool CircleImp::isPropertyDefinedOnOrThroughThisImp( int which ) const
{
  assert( which < CircleImp::numberOfProperties() );
  if ( which < CurveImp::numberOfProperties() )
    return CurveImp::isPropertyDefinedOnOrThroughThisImp( which );
  return false;
}

Rect CircleImp::surroundingRect() const
{
  Coordinate d( mradius, mradius );
  return Rect( mcenter - d, mcenter + d );
}
