#include <gtk/gtk.h>

#include "snapped-point.h"

#include "preferences.h"

Inkscape::SnappedPoint::SnappedPoint(Geom::Point const &p, SnapTargetType const &target, Geom::Coord const &d, Geom::Coord const &t, bool const &a, bool const &fully_constrained)

: _point(p), _target(target), _distance(d), _tolerance(std::max(t,1.0)), _always_snap(a)

{

// tolerance should never be smaller than 1 px, as it is used for normalization in isOtherSnapBetter. We don't want a division by zero.

_fully_constrained = fully_constrained;

_second_distance = NR_HUGE;

_second_tolerance = 1;

_second_always_snap = false;

_transformation = Geom::Point(1,1);

_pointer_distance = NR_HUGE;

}

Inkscape::SnappedPoint::SnappedPoint(Geom::Point const &p, SnapTargetType const &target, Geom::Coord const &d, Geom::Coord const &t, bool const &a, bool const &at_intersection, bool const &fully_constrained, Geom::Coord const &d2, Geom::Coord const &t2, bool const &a2)

: _point(p), _target(target), _at_intersection(at_intersection), _fully_constrained(fully_constrained), _distance(d), _tolerance(std::max(t,1.0)), _always_snap(a),

_second_distance(d2), _second_tolerance(std::max(t2,1.0)), _second_always_snap(a2)

{

// tolerance should never be smaller than 1 px, as it is used for normalization in

// isOtherSnapBetter. We don't want a division by zero.

_transformation = Geom::Point(1,1);

_pointer_distance = NR_HUGE;

}

Inkscape::SnappedPoint::SnappedPoint()

{

_point = Geom::Point(0,0);

_target = SNAPTARGET_UNDEFINED,

_distance = NR_HUGE;

_tolerance = 1;

_always_snap = false;

_at_intersection = false;

_second_distance = NR_HUGE;

_second_tolerance = 1;

_second_always_snap = false;

_transformation = Geom::Point(1,1);

_pointer_distance = NR_HUGE;

}

Inkscape::SnappedPoint::~SnappedPoint()

{

}

void Inkscape::SnappedPoint::getPoint(Geom::Point &p) const

{

// When we have snapped

if (getSnapped()) {

// then return the snapped point by overwriting p

p = _point;

} //otherwise p will be left untouched; this way the caller doesn't have to check wether we've snapped

}

bool getClosestSP(std::list<Inkscape::SnappedPoint> &list, Inkscape::SnappedPoint &result)

{

bool success = false;

for (std::list<Inkscape::SnappedPoint>::const_iterator i = list.begin(); i != list.end(); i++) {

if ((i == list.begin()) || (*i).getSnapDistance() < result.getSnapDistance()) {

result = *i;

success = true;

}

}

return success;

}

bool Inkscape::SnappedPoint::isOtherSnapBetter(Inkscape::SnappedPoint const &other_one, bool weighted) const

{

double dist_other = other_one.getSnapDistance();

double dist_this = getSnapDistance();

// The distance to the pointer should only be taken into account when finding the best snapped source node (when

// there's more than one). It is not useful when trying to find the best snapped target point.

// (both the snap distance and the pointer distance are measured in document pixels, not in screen pixels)

if (weighted) {

// weigth factor: controls which node should be preferrerd for snapping, which is either

// the node with the closest snap (w = 0), or the node closest to the mousepointer (w = 1)

Inkscape::Preferences *prefs = Inkscape::Preferences::get();

double w = prefs->getDoubleLimited("/options/snapweight/value", 0.5, 0, 1);

if (prefs->getBool("/options/snapclosestonly/value", false)) {

w = 1;

}

if (w > 0) {

// When accounting for the distance to the mouse pointer, then at least one of the snapped points should

// have that distance set. If not, then this is a bug. Either "weighted" must be set to false, or the

// mouse pointer distance must be set.

g_assert(getPointerDistance() != NR_HUGE || other_one.getPointerDistance() != NR_HUGE);

// The snap distance will always be smaller than the tolerance set for the snapper. The pointer distance can

// however be very large. To compare these in a fair way, we will have to normalize these metrics first

// The closest pointer distance will be normalized to 1.0; the other one will be > 1.0

// The snap distance will be normalized to 1.0 if it's equal to the snapper tolerance

double const norm_p = std::min(getPointerDistance(), other_one.getPointerDistance());

double const norm_t_other = std::min(50.0, other_one.getTolerance());

double const norm_t_this = std::min(50.0, getTolerance());

dist_other = w * other_one.getPointerDistance() / norm_p + (1-w) * dist_other / norm_t_other;

dist_this = w * getPointerDistance() / norm_p + (1-w) * dist_this / norm_t_this;

}

}

// If it's closer

bool c1 = dist_other < dist_this;

// or, if it's for a snapper with "always snap" turned on, and the previous wasn't

bool c2 = other_one.getAlwaysSnap() && !getAlwaysSnap();

// But in no case fall back from a snapper with "always snap" on to one with "always snap" off

bool c2n = !other_one.getAlwaysSnap() && getAlwaysSnap();

// or, if we have a fully constrained snappoint (e.g. to a node or an intersection), while the previous one was only partly constrained (e.g. to a line)

bool c3 = other_one.getFullyConstrained() && !getFullyConstrained();

// But in no case fall back; (has less priority than c3n, so it is allowed to fall back when c3 is true, see below)

bool c3n = !other_one.getFullyConstrained() && getFullyConstrained();

// or, if it's just as close then consider the second distance

bool c4a = (dist_other == dist_this);

bool c4b = other_one.getSecondSnapDistance() < getSecondSnapDistance();

// std::cout << "c1 = " << c1 << " | c2 = " << c2 << " | c2n = " << c2n << " | c3 = " << c3 << " | c3n = " << c3n << " | c4a = " << c4a << " | c4b = " << c4b << std::endl;

return (c1 || c2 || c3 || (c4a && c4b)) && !c2n && (!c3n || c2);

}