#include "libnr/n-art-bpath.h"

#include "libnr/nr-rect-ops.h"

#include "document.h"

#include "sp-namedview.h"

#include "sp-image.h"

#include "sp-item-group.h"

#include "sp-item.h"

#include "sp-use.h"

#include "display/curve.h"

#include "desktop.h"

#include "inkscape.h"

#include "prefs-utils.h"

#include "sp-text.h"

#include "sp-flowtext.h"

#include "text-editing.h"

Inkscape::ObjectSnapper::ObjectSnapper(SPNamedView const *nv, NR::Coord const d)

: Snapper(nv, d), _snap_to_itemnode(true), _snap_to_itempath(true),

_snap_to_bboxnode(true), _snap_to_bboxpath(true), _strict_snapping(true),

_include_item_center(false)

{

_candidates = new std::list<SPItem*>;

_points_to_snap_to = new std::list<NR::Point>;

_paths_to_snap_to = new std::list<Path*>;

}

Inkscape::ObjectSnapper::~ObjectSnapper()

{

_candidates->clear(); //Don't delete the candidates themselves, as these are not ours!

delete _candidates;

_points_to_snap_to->clear();

delete _points_to_snap_to;

for (std::list<Path*>::const_iterator k = _paths_to_snap_to->begin(); k != _paths_to_snap_to->end(); k++) {

delete *k;

}

_paths_to_snap_to->clear();

delete _paths_to_snap_to;

}

void Inkscape::ObjectSnapper::_findCandidates(SPObject* r,

std::list<SPItem const *> const &it,

bool const &first_point,

std::vector<NR::Point> &points_to_snap,

DimensionToSnap const snap_dim) const

{

if (ThisSnapperMightSnap()) {

SPDesktop const *desktop = SP_ACTIVE_DESKTOP;

if (first_point) {

_candidates->clear();

}

for (SPObject* o = sp_object_first_child(r); o != NULL; o = SP_OBJECT_NEXT(o)) {

if (SP_IS_ITEM(o) && !SP_ITEM(o)->isLocked() && !desktop->itemIsHidden(SP_ITEM(o))) {

/* See if this item is on the ignore list */

std::list<SPItem const *>::const_iterator i = it.begin();

while (i != it.end() && *i != o) {

i++;

}

if (i == it.end()) {

/* See if the item is within range */

if (SP_IS_GROUP(o)) {

_findCandidates(o, it, false, points_to_snap, snap_dim);

} else {

// Now let's see if any of the snapping points is within

// snapping range of this object

NR::Maybe<NR::Rect> b = sp_item_bbox_desktop(SP_ITEM(o));

if (b) {

for (std::vector<NR::Point>::const_iterator i = points_to_snap.begin(); i != points_to_snap.end(); i++) {

NR::Point b_min = b->min();

NR::Point b_max = b->max();

double d = getDistance();

bool withinX = ((*i)[NR::X] >= b_min[NR::X] - d) && ((*i)[NR::X] <= b_max[NR::X] + d);

bool withinY = ((*i)[NR::Y] >= b_min[NR::Y] - d) && ((*i)[NR::Y] <= b_max[NR::Y] + d);

if (snap_dim == SNAP_X && withinX || snap_dim == SNAP_Y && withinY || snap_dim == SNAP_XY && withinX && withinY) {

//We've found a point that is within snapping range

//of this object, so record it as a candidate

_candidates->push_back(SP_ITEM(o));

break;

}

}

}

}

}

}

}

}

}

void Inkscape::ObjectSnapper::_snapNodes(Inkscape::Snapper::PointType const &t,

Inkscape::SnappedPoint &s,

NR::Point const &p,

bool const &first_point,

DimensionToSnap const snap_dim) const

{

/* FIXME: this seems like a hack. Perhaps Snappers should be

SPDesktop const *desktop = SP_ACTIVE_DESKTOP;

// Determine the type of bounding box we should snap to

SPItem::BBoxType bbox_type = SPItem::GEOMETRIC_BBOX;

if (_snap_to_bboxnode) {

gchar const *prefs_bbox = prefs_get_string_attribute("tools.select", "bounding_box");

bbox_type = (prefs_bbox != NULL && strcmp(prefs_bbox, "geometric")==0)? SPItem::GEOMETRIC_BBOX : SPItem::APPROXIMATE_BBOX;

}

bool p_is_a_node = t & Inkscape::Snapper::SNAPPOINT_NODE;

bool p_is_a_bbox = t & Inkscape::Snapper::SNAPPOINT_BBOX;

bool p_is_a_guide = t & Inkscape::Snapper::SNAPPOINT_GUIDE;

// A point considered for snapping should be either a node, a bbox corner or a guide. Pick only ONE!

g_assert(!(p_is_a_node && p_is_a_bbox || p_is_a_bbox && p_is_a_guide || p_is_a_node && p_is_a_guide));

// Now, let's first collect all points to snap to. If we have a whole bunch of points to snap,

// e.g. when translating an item using the selector tool, then we will only do this for the

// first point and store the collection for later use. This dramatically improves the performance

if (first_point) {

_points_to_snap_to->clear();

for (std::list<SPItem*>::const_iterator i = _candidates->begin(); i != _candidates->end(); i++) {

NR::Matrix i2doc(NR::identity());

SPItem *root_item = NULL;

if (SP_IS_USE(*i)) {

i2doc = sp_use_get_root_transform(SP_USE(*i));

root_item = sp_use_root(SP_USE(*i));

} else {

i2doc = sp_item_i2doc_affine(*i);

root_item = *i;

}

SPCurve *curve = NULL;

if (SP_IS_SHAPE(root_item)) {

SPShape const *sh = SP_SHAPE(root_item);

curve = sh->curve;

} else if (SP_IS_IMAGE(root_item)) {

SPImage const *im = SP_IMAGE(root_item);

curve = im->curve;

}

//Collect all nodes so we can snap to them

if (_snap_to_itemnode) {

if (!(_strict_snapping && !p_is_a_node) || p_is_a_guide) {

if (curve) {

int j = 0;

while (SP_CURVE_BPATH(curve)[j].code != NR_END) {

/* Get this node in desktop coordinates */

NArtBpath const &bp = SP_CURVE_BPATH(curve)[j];

_points_to_snap_to->push_back(desktop->doc2dt(bp.c(3) * i2doc));

j++;

}

if (_include_item_center) {

_points_to_snap_to->push_back(root_item->getCenter());

}

}

}

}

//Collect the bounding box's corners so we can snap to them

if (_snap_to_bboxnode) {

if (!(_strict_snapping && !p_is_a_bbox) || p_is_a_guide) {

NR::Maybe<NR::Rect> b = sp_item_bbox_desktop(root_item, bbox_type);

if (b) {

for ( unsigned k = 0 ; k < 4 ; k++ ) {

_points_to_snap_to->push_back(b->corner(k));

}

}

}

}

}

}

//Do the snapping, using all the nodes and corners collected above

for (std::list<NR::Point>::const_iterator k = _points_to_snap_to->begin(); k != _points_to_snap_to->end(); k++) {

/* Try to snap to this node of the path */

NR::Coord dist = NR_HUGE;

NR::Point snapped_point;

switch (snap_dim) {

case SNAP_X:

dist = fabs((*k)[NR::X] - p[NR::X]);

snapped_point = NR::Point((*k)[NR::X], p[NR::Y]);

break;

case SNAP_Y:

dist = fabs((*k)[NR::Y] - p[NR::Y]);

snapped_point = NR::Point(p[NR::X], (*k)[NR::Y]);

break;

case SNAP_XY:

dist = NR::L2(*k - p);

snapped_point = *k;

break;

}

if (dist < getDistance() && dist < s.getDistance()) {

s = SnappedPoint(snapped_point, dist);

}

}

}

void Inkscape::ObjectSnapper::_snapPaths(Inkscape::Snapper::PointType const &t,

Inkscape::SnappedPoint &s,

NR::Point const &p,

bool const &first_point) const

{

/* FIXME: this seems like a hack. Perhaps Snappers should be

SPDesktop const *desktop = SP_ACTIVE_DESKTOP;

NR::Point const p_doc = desktop->dt2doc(p);

// Determine the type of bounding box we should snap to

SPItem::BBoxType bbox_type = SPItem::GEOMETRIC_BBOX;

if (_snap_to_bboxpath) {

gchar const *prefs_bbox = prefs_get_string_attribute("tools.select", "bounding_box");

bbox_type = (prefs_bbox != NULL && strcmp(prefs_bbox, "geometric")==0)? SPItem::GEOMETRIC_BBOX : SPItem::APPROXIMATE_BBOX;

}

bool p_is_a_node = t & Inkscape::Snapper::SNAPPOINT_NODE;

// Now, let's first collect all paths to snap to. If we have a whole bunch of points to snap,

// e.g. when translating an item using the selector tool, then we will only do this for the

// first point and store the collection for later use. This dramatically improves the performance

if (first_point) {

for (std::list<Path*>::const_iterator k = _paths_to_snap_to->begin(); k != _paths_to_snap_to->end(); k++) {

delete *k;

}

_paths_to_snap_to->clear();

for (std::list<SPItem*>::const_iterator i = _candidates->begin(); i != _candidates->end(); i++) {

/* Transform the requested snap point to this item's coordinates */

NR::Matrix i2doc(NR::identity());

SPItem *root_item = NULL;

/* We might have a clone at hand, so make sure we get the root item */

if (SP_IS_USE(*i)) {

i2doc = sp_use_get_root_transform(SP_USE(*i));

root_item = sp_use_root(SP_USE(*i));

} else {

i2doc = sp_item_i2doc_affine(*i);

root_item = *i;

}

//Build a list of all paths considered for snapping to

//Add the item's path to snap to

if (_snap_to_itempath) {

if (!(_strict_snapping && !p_is_a_node)) {

// Snapping to the path of characters is very cool, but for a large

// chunk of text this will take ages! So limit snapping to text paths

// containing max. 240 characters. Snapping the bbox will not be affected

bool very_lenghty_prose = false;

if (SP_IS_TEXT(root_item) || SP_IS_FLOWTEXT(root_item)) {

very_lenghty_prose = sp_text_get_length(SP_TEXT(root_item)) > 240;

}

// On my AMD 3000+, the snapping lag becomes annoying at approx. 240 chars

// which corresponds to a lag of 500 msec. This is for snapping a rect

// to a single line of text.

// Snapping for example to a traced bitmap is also very stressing for

// the CPU, so we'll only snap to paths having no more than 500 nodes

// This also leads to a lag of approx. 500 msec (in my lousy test set-up).

bool very_complex_path = false;

if (SP_IS_PATH(root_item)) {

very_complex_path = sp_nodes_in_path(SP_PATH(root_item)) > 500;

}

if (!very_lenghty_prose && !very_complex_path) {

_paths_to_snap_to->push_back(Path_for_item(root_item, true, true));

}

}

}

//Add the item's bounding box to snap to

if (_snap_to_bboxpath) {

if (!(_strict_snapping && p_is_a_node)) {

//This will get ugly... rect -> curve -> bpath

NRRect rect;

sp_item_invoke_bbox(root_item, &rect, i2doc, TRUE, bbox_type);

NR::Maybe<NR::Rect> bbox = rect.upgrade();

SPCurve *curve = sp_curve_new_from_rect(bbox);

if (curve) {

NArtBpath *bpath = SP_CURVE_BPATH(curve);

if (bpath) {

Path *path = bpath_to_Path(bpath);

if (path) {

_paths_to_snap_to->push_back(path);

}

delete bpath;

}

delete curve;

}

}

}

}

}

//Now we can finally do the real snapping, using the paths collected above

for (std::list<Path*>::const_iterator k = _paths_to_snap_to->begin(); k != _paths_to_snap_to->end(); k++) {

if (*k) {

if (first_point) {

(*k)->ConvertWithBackData(0.01); //This is extremely time consuming!

}

/* Look for the nearest position on this SPItem to our snap point */

NR::Maybe<Path::cut_position> const o = get_nearest_position_on_Path(*k, p_doc);

if (o && o->t >= 0 && o->t <= 1) {

/* Convert the nearest point back to desktop coordinates */

NR::Point const o_it = get_point_on_Path(*k, o->piece, o->t);

NR::Point const o_dt = desktop->doc2dt(o_it);

NR::Coord const dist = NR::L2(o_dt - p);

if (dist < getDistance() && dist < s.getDistance()) {

s = SnappedPoint(o_dt, dist);

}

}

}

}

}

Inkscape::SnappedPoint Inkscape::ObjectSnapper::_doFreeSnap(Inkscape::Snapper::PointType const &t,

NR::Point const &p,

bool const &first_point,

std::vector<NR::Point> &points_to_snap,

std::list<SPItem const *> const &it) const

{

if ( NULL == _named_view ) {

return SnappedPoint(p, NR_HUGE);

}

/* Get a list of all the SPItems that we will try to snap to */

if (first_point) {

_findCandidates(sp_document_root(_named_view->document), it, first_point, points_to_snap, SNAP_XY);

}

SnappedPoint s(p, NR_HUGE);

if (_snap_to_itemnode || _snap_to_bboxnode) {

_snapNodes(t, s, p, first_point, SNAP_XY);

}

if (_snap_to_itempath || _snap_to_bboxpath) {

_snapPaths(t, s, p, first_point);

}

return s;

}

Inkscape::SnappedPoint Inkscape::ObjectSnapper::_doConstrainedSnap(Inkscape::Snapper::PointType const &t,

NR::Point const &p,

bool const &first_point,

std::vector<NR::Point> &points_to_snap,

ConstraintLine const &c,

std::list<SPItem const *> const &it) const

{

/* FIXME: this needs implementing properly; I think we have to do the

return _doFreeSnap(t, p, first_point, points_to_snap, it);

}

Inkscape::SnappedPoint Inkscape::ObjectSnapper::guideSnap(NR::Point const &p,

DimensionToSnap const snap_dim) const

{

if ( NULL == _named_view ) {

return SnappedPoint(p, NR_HUGE);

}

/* Get a list of all the SPItems that we will try to snap to */

std::list<SPItem*> cand;

std::list<SPItem const *> const it; //just an empty list

std::vector<NR::Point> points_to_snap;

points_to_snap.push_back(p);

_findCandidates(sp_document_root(_named_view->document), it, true, points_to_snap, snap_dim);

SnappedPoint s(p, NR_HUGE);

_snapNodes(Inkscape::Snapper::SNAPPOINT_GUIDE, s, p, true, snap_dim);

return s;

}

bool Inkscape::ObjectSnapper::ThisSnapperMightSnap() const

{

bool snap_to_something = _snap_to_itempath || _snap_to_itemnode || _snap_to_bboxpath || _snap_to_bboxnode;

return (_enabled && _snap_from != 0 && snap_to_something);

}