#include <2geom/line.h>

#include "line-snapper.h"

#include "snapped-line.h"

#include "snap.h"

Inkscape::LineSnapper::LineSnapper(SnapManager *sm, Geom::Coord const d) : Snapper(sm, d)

{

}

void Inkscape::LineSnapper::freeSnap(SnappedConstraints &sc,

Inkscape::SnapCandidatePoint const &p,

Geom::OptRect const &/*bbox_to_snap*/,

std::vector<SPItem const *> const */*it*/,

std::vector<Inkscape::SnapCandidatePoint> */*unselected_nodes*/) const

{

if (!(_snap_enabled && _snapmanager->snapprefs.getSnapFrom(p.getSourceType())) ) {

return;

}

/* Get the lines that we will try to snap to */

const LineList lines = _getSnapLines(p.getPoint());

for (LineList::const_iterator i = lines.begin(); i != lines.end(); i++) {

Geom::Point const p1 = i->second; // point at guide/grid line

Geom::Point const p2 = p1 + Geom::rot90(i->first); // 2nd point at guide/grid line

// std::cout << " line through " << i->second << " with normal " << i->first;

g_assert(i->first != Geom::Point(0,0)); // we cannot project on an linesegment of zero length

Geom::Point const p_proj = Geom::projection(p.getPoint(), Geom::Line(p1, p2));

Geom::Coord const dist = Geom::L2(p_proj - p.getPoint());

//Store any line that's within snapping range

if (dist < getSnapperTolerance()) {

_addSnappedLine(sc, p_proj, dist, p.getSourceType(), p.getSourceNum(), i->first, i->second);

// For any line that's within range, we will also look at it's "point on line" p1. For guides

// this point coincides with its origin; for grids this is of no use, but we cannot

// discern between grids and guides here

Geom::Coord const dist_p1 = Geom::L2(p1 - p.getPoint());

if (dist_p1 < getSnapperTolerance()) {

_addSnappedLinesOrigin(sc, p1, dist_p1, p.getSourceType(), p.getSourceNum());

// Only relevant for guides; grids don't have an origin per line

// Therefore _addSnappedLinesOrigin() will only be implemented for guides

}

// std::cout << " -> distance = " << dist;

}

// std::cout << std::endl;

}

}

void Inkscape::LineSnapper::constrainedSnap(SnappedConstraints &sc,

Inkscape::SnapCandidatePoint const &p,

Geom::OptRect const &/*bbox_to_snap*/,

ConstraintLine const &c,

std::vector<SPItem const *> const */*it*/) const

{

if (_snap_enabled == false || _snapmanager->snapprefs.getSnapFrom(p.getSourceType()) == false) {

return;

}

/* Get the lines that we will try to snap to */

const LineList lines = _getSnapLines(p.getPoint());

for (LineList::const_iterator i = lines.begin(); i != lines.end(); i++) {

if (Geom::L2(c.getDirection()) > 0) { // Can't do a constrained snap without a constraint

// constraint line

Geom::Point const point_on_line = c.hasPoint() ? c.getPoint() : p.getPoint();

Geom::Line line1(point_on_line, point_on_line + c.getDirection());

// grid/guide line

Geom::Point const p1 = i->second; // point at guide/grid line

Geom::Point const p2 = p1 + Geom::rot90(i->first); // 2nd point at guide/grid line

Geom::Line line2(p1, p2);

Geom::OptCrossing inters = Geom::OptCrossing(); // empty by default

try

{

inters = Geom::intersection(line1, line2);

}

catch (Geom::InfiniteSolutions e)

{

// We're probably dealing with parallel lines, so snapping doesn't make any sense here

continue; // jump to the next iterator in the for-loop

}

if (inters) {

Geom::Point t = line1.pointAt((*inters).ta);

const Geom::Coord dist = Geom::L2(t - p.getPoint());

if (dist < getSnapperTolerance()) {

// When doing a constrained snap, we're already at an intersection.

// This snappoint is therefore fully constrained, so there's no need

// to look for additional intersections; just return the snapped point

// and forget about the line

_addSnappedPoint(sc, t, dist, p.getSourceType(), p.getSourceNum());

// For any line that's within range, we will also look at it's "point on line" p1. For guides

// this point coincides with its origin; for grids this is of no use, but we cannot

// discern between grids and guides here

Geom::Coord const dist_p1 = Geom::L2(p1 - p.getPoint());

if (dist_p1 < getSnapperTolerance()) {

_addSnappedLinesOrigin(sc, p1, dist_p1, p.getSourceType(), p.getSourceNum());

// Only relevant for guides; grids don't have an origin per line

// Therefore _addSnappedLinesOrigin() will only be implemented for guides

}

}

}

}

}

}

void Inkscape::LineSnapper::_addSnappedLinesOrigin(SnappedConstraints &/*sc*/, Geom::Point const /*origin*/, Geom::Coord const /*snapped_distance*/, SnapSourceType const &/*source_type*/, long /*source_num*/) const

{

}