/* === S Y N F I G ========================================================= */
/*!	\file circle.cpp
**	\brief Implementation of the "Circle" layer
**
**	$Id$
**
**	\legal
**	Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
**	Copyright (c) 2008 Chris Moore
**	Copyright (c) 2011-2013 Carlos López
**
**	This package 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 package 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.
**	\endlegal
*/
/* ========================================================================= */

/* === H E A D E R S ======================================================= */

#ifdef USING_PCH
#	include "pch.h"
#else
#ifdef HAVE_CONFIG_H
#	include <config.h>
#endif

#include <synfig/localization.h>
#include <synfig/general.h>

#include "circle.h"
#include <synfig/context.h>

#endif

using namespace synfig;
using namespace std;
using namespace etl;

/* -- G L O B A L S --------------------------------------------------------- */

SYNFIG_LAYER_INIT(Circle);
SYNFIG_LAYER_SET_NAME(Circle,"circle");
SYNFIG_LAYER_SET_LOCAL_NAME(Circle,N_("Circle"));
SYNFIG_LAYER_SET_CATEGORY(Circle,N_("Geometry"));
SYNFIG_LAYER_SET_VERSION(Circle,"0.2");
SYNFIG_LAYER_SET_CVS_ID(Circle,"$Id$");

/* -- F U N C T I O N S ----------------------------------------------------- */

Circle::Circle():
	param_radius    (Real(1))
{
	SET_INTERPOLATION_DEFAULTS();
	SET_STATIC_DEFAULTS();
}

void
Circle::sync_vfunc()
{
	const int num_splines = 8;
	const Angle::deg angle(180.0/(Real)num_splines);
	const Real k = 1.0 / Angle::cos(angle).get();

	Real radius = fabs(param_radius.get(Real()));

	Matrix2 matrix;
	matrix.set_rotate(angle);

	Vector p0, p1, p2(radius, 0.0);
	clear();
	move_to(p2[0], p2[1]);
	for(int i = 0; i < num_splines; ++i)
	{
		Vector p0 = p2;
		p1 = matrix.get_transformed(p0);
		p2 = matrix.get_transformed(p1);
		conic_to(p2[0], p2[1], k*p1[0], k*p1[1]);
	}
	close();
}

bool
Circle::set_shape_param(const synfig::String & param, const synfig::ValueBase &value)
{
	IMPORT_VALUE(param_radius);
	return false;
}

bool
Circle::set_param(const String &param, const ValueBase &value)
{
	if (set_shape_param(param, value))
		{ force_sync(); return true; }

	if ( param == "color"
	  || param == "invert"
	  || param == "origin"
	  || param == "feather" )
		return Layer_Shape::set_param(param, value);

	if ( param == "pos" )
		return Layer_Shape::set_param("origin", value);

	return Layer_Composite::set_param(param,value);
}

ValueBase
Circle::get_param(const String &param)const
{
	EXPORT_VALUE(param_radius);

	EXPORT_NAME();
	EXPORT_VERSION();

	if ( param == "color"
	  || param == "invert"
	  || param == "origin"
	  || param == "feather" )
		return Layer_Shape::get_param(param);

	if ( param == "pos" )
		return Layer_Shape::get_param("origin");

	return Layer_Composite::get_param(param);
}

Layer::Vocab
Circle::get_param_vocab()const
{
	Layer::Vocab ret(Layer_Composite::get_param_vocab());
	Layer::Vocab shape(Layer_Shape::get_param_vocab());

	ret.push_back(shape["color"]);
	ret.push_back(ParamDesc("radius")
		.set_local_name(_("Radius"))
		.set_origin("origin")
		.set_description(_("Radius of the circle"))
		.set_is_distance()
	);
	ret.push_back(shape["feather"]);
	ret.push_back(shape["origin"]);
	ret.push_back(shape["invert"]);

	return ret;
}

// It is possible to remove hit_check() function, but in this case the following bug will appear - 
// https://github.com/synfig/synfig/issues/442
synfig::Layer::Handle
Circle::hit_check(synfig::Context context, const synfig::Point &point)const
{
	Real radius = param_radius.get(Real());
	Real feather = param_feather.get(Real());
	Point origin = param_origin.get(Point());
	bool invert = param_invert.get(bool());
	
	Point temp=origin-point;

	if(get_amount()==0)
		return context.hit_check(point);

	bool in_circle(temp.mag_squared() <= radius*radius);

	if(invert)
	{
		in_circle=!in_circle;
		if(in_circle && get_amount()-(feather/radius)<=0.1 && get_blend_method()!=Color::BLEND_STRAIGHT)
			in_circle=false;
	}
	else
	{
		if(get_amount()-(feather/radius)<=0.0)
			in_circle=false;
	}

	if(in_circle)
	{
		synfig::Layer::Handle tmp;
		if(get_blend_method()==Color::BLEND_BEHIND && (tmp=context.hit_check(point)))
			return tmp;
		if(Color::is_onto(get_blend_method()) && !(tmp=context.hit_check(point)))
			return 0;
		return const_cast<Circle*>(this);
	}

	return context.hit_check(point);
}