/*
 * SVG <g> implementation
 *
 * Authors:
 *   Lauris Kaplinski <lauris@kaplinski.com>
 *   bulia byak <buliabyak@users.sf.net>
 *   Johan Engelen <j.b.c.engelen@ewi.utwente.nl>
 *   Jon A. Cruz <jon@joncruz.org>
 *   Abhishek Sharma
 *
 * Copyright (C) 1999-2006 authors
 * Copyright (C) 2000-2001 Ximian, Inc.
 *
 * Released under GNU GPL, read the file 'COPYING' for more information
 */

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <glibmm/i18n.h>
#include <cstring>
#include <string>

#include "display/drawing-group.h"
#include "display/curve.h"
#include "xml/repr.h"
#include "svg/svg.h"
#include "document.h"
#include "document-undo.h"
#include "style.h"
#include "attributes.h"
#include "sp-item-transform.h"
#include "sp-root.h"
#include "sp-use.h"
#include "sp-offset.h"
#include "sp-clippath.h"
#include "sp-mask.h"
#include "sp-path.h"
#include "box3d.h"
#include "persp3d.h"
#include "inkscape.h"
#include "desktop-handles.h"
#include "selection.h"
#include "live_effects/effect.h"
#include "live_effects/lpeobject.h"
#include "live_effects/lpeobject-reference.h"
#include "sp-title.h"
#include "sp-desc.h"
#include "sp-switch.h"
#include "sp-defs.h"
#include "verbs.h"
#include "layer-model.h"
#include "sp-textpath.h"
#include "sp-flowtext.h"

using Inkscape::DocumentUndo;

static void sp_group_perform_patheffect(SPGroup *group, SPGroup *topgroup, bool write);

#include "sp-factory.h"

namespace {
	SPObject* createGroup() {
		return new SPGroup();
	}

	bool groupRegistered = SPFactory::instance().registerObject("svg:g", createGroup);
}

SPGroup::SPGroup() : SPLPEItem() {
    this->_layer_mode = SPGroup::GROUP;
    //new (&this->_display_modes) std::map<unsigned int, SPGroup::LayerMode>();
}

SPGroup::~SPGroup() {
	//this->_display_modes.~map();
}

void SPGroup::build(SPDocument *document, Inkscape::XML::Node *repr) {
    this->readAttr( "inkscape:groupmode" );

    SPLPEItem::build(document, repr);
}

void SPGroup::release() {
    if (this->_layer_mode == SPGroup::LAYER) {
        this->document->removeResource("layer", this);
    }

    SPLPEItem::release();
}

void SPGroup::child_added(Inkscape::XML::Node* child, Inkscape::XML::Node* ref) {
    SPLPEItem::child_added(child, ref);

    SPObject *last_child = this->lastChild();

    if (last_child && last_child->getRepr() == child) {
        // optimization for the common special case where the child is being added at the end
        SPObject *ochild = last_child;
        if ( SP_IS_ITEM(ochild) ) {
            /* TODO: this should be moved into SPItem somehow */
            SPItemView *v;
            Inkscape::DrawingItem *ac;

            for (v = this->display; v != NULL; v = v->next) {
                ac = SP_ITEM (ochild)->invoke_show (v->arenaitem->drawing(), v->key, v->flags);

                if (ac) {
                    v->arenaitem->appendChild(ac);
                }
            }
        }
    } else {    // general case
        SPObject *ochild = this->get_child_by_repr(child);
        if ( ochild && SP_IS_ITEM(ochild) ) {
            /* TODO: this should be moved into SPItem somehow */
            SPItemView *v;
            Inkscape::DrawingItem *ac;

            unsigned position = SP_ITEM(ochild)->pos_in_parent();

            for (v = this->display; v != NULL; v = v->next) {
                ac = SP_ITEM (ochild)->invoke_show (v->arenaitem->drawing(), v->key, v->flags);

                if (ac) {
                    v->arenaitem->prependChild(ac);
                    ac->setZOrder(position);
                }
            }
        }
    }

    this->requestModified(SP_OBJECT_MODIFIED_FLAG);
}

/* fixme: hide (Lauris) */

void SPGroup::remove_child(Inkscape::XML::Node *child) {
    SPLPEItem::remove_child(child);

    this->requestModified(SP_OBJECT_MODIFIED_FLAG);
}

void SPGroup::order_changed (Inkscape::XML::Node *child, Inkscape::XML::Node *old_ref, Inkscape::XML::Node *new_ref)
{
	SPLPEItem::order_changed(child, old_ref, new_ref);

    SPObject *ochild = this->get_child_by_repr(child);
    if ( ochild && SP_IS_ITEM(ochild) ) {
        /* TODO: this should be moved into SPItem somehow */
        SPItemView *v;
        unsigned position = SP_ITEM(ochild)->pos_in_parent();
        for ( v = SP_ITEM (ochild)->display ; v != NULL ; v = v->next ) {
            v->arenaitem->setZOrder(position);
        }
    }

    this->requestModified(SP_OBJECT_MODIFIED_FLAG);
}

void SPGroup::update(SPCtx *ctx, unsigned int flags) {
    SPLPEItem::update(ctx, flags);

    SPItemCtx *ictx, cctx;

    ictx = (SPItemCtx *) ctx;
    cctx = *ictx;

    if (flags & SP_OBJECT_MODIFIED_FLAG) {
      flags |= SP_OBJECT_PARENT_MODIFIED_FLAG;
    }

    flags &= SP_OBJECT_MODIFIED_CASCADE;

    if (flags & SP_OBJECT_STYLE_MODIFIED_FLAG) {
        for (SPItemView *v = this->display; v != NULL; v = v->next) {
            Inkscape::DrawingGroup *group = dynamic_cast<Inkscape::DrawingGroup *>(v->arenaitem);
            group->setStyle(this->style);
        }
    }

    GSList *l = g_slist_reverse(this->childList(true, SPObject::ActionUpdate));
    while (l) {
        SPObject *child = SP_OBJECT (l->data);
        l = g_slist_remove (l, child);

        if (flags || (child->uflags & (SP_OBJECT_MODIFIED_FLAG | SP_OBJECT_CHILD_MODIFIED_FLAG))) {
            if (SP_IS_ITEM (child)) {
                SPItem const &chi = *SP_ITEM(child);
                cctx.i2doc = chi.transform * ictx->i2doc;
                cctx.i2vp = chi.transform * ictx->i2vp;
                child->updateDisplay((SPCtx *)&cctx, flags);
            } else {
                child->updateDisplay(ctx, flags);
            }
        }

        sp_object_unref(child);
    }
}

void SPGroup::modified(guint flags) {
    SPLPEItem::modified(flags);

    SPObject *child;

    if (flags & SP_OBJECT_MODIFIED_FLAG) {
    	flags |= SP_OBJECT_PARENT_MODIFIED_FLAG;
    }

    flags &= SP_OBJECT_MODIFIED_CASCADE;

    if (flags & SP_OBJECT_STYLE_MODIFIED_FLAG) {
        for (SPItemView *v = this->display; v != NULL; v = v->next) {
            Inkscape::DrawingGroup *group = dynamic_cast<Inkscape::DrawingGroup *>(v->arenaitem);
            group->setStyle(this->style);
        }
    }

    GSList *l = g_slist_reverse(this->childList(true));

    while (l) {
        child = SP_OBJECT (l->data);
        l = g_slist_remove (l, child);

        if (flags || (child->mflags & (SP_OBJECT_MODIFIED_FLAG | SP_OBJECT_CHILD_MODIFIED_FLAG))) {
            child->emitModified(flags);
        }

        sp_object_unref(child);
    }
}

Inkscape::XML::Node* SPGroup::write(Inkscape::XML::Document *xml_doc, Inkscape::XML::Node *repr, guint flags) {
	SPGroup* object = this;
    SPGroup *group = SP_GROUP(object);

    if (flags & SP_OBJECT_WRITE_BUILD) {
        GSList *l;

        if (!repr) {
            if (SP_IS_SWITCH(object)) {
                repr = xml_doc->createElement("svg:switch");
            } else {
                repr = xml_doc->createElement("svg:g");
            }
        }

        l = NULL;

        for (SPObject *child = object->firstChild(); child; child = child->getNext() ) {
            if ( !SP_IS_TITLE(child) && !SP_IS_DESC(child) ) {
                Inkscape::XML::Node *crepr = child->updateRepr(xml_doc, NULL, flags);

                if (crepr) {
                    l = g_slist_prepend (l, crepr);
                }
            }
        }

        while (l) {
            repr->addChild((Inkscape::XML::Node *) l->data, NULL);
            Inkscape::GC::release((Inkscape::XML::Node *) l->data);
            l = g_slist_remove (l, l->data);
        }
    } else {
        for (SPObject *child = object->firstChild() ; child ; child = child->getNext() ) {
            if ( !SP_IS_TITLE(child) && !SP_IS_DESC(child) ) {
                child->updateRepr(flags);
            }
        }
    }

    if ( flags & SP_OBJECT_WRITE_EXT ) {
        const char *value;
        if ( group->_layer_mode == SPGroup::LAYER ) {
            value = "layer";
        } else if ( group->_layer_mode == SPGroup::MASK_HELPER ) {
            value = "maskhelper";
        } else if ( flags & SP_OBJECT_WRITE_ALL ) {
            value = "group";
        } else {
            value = NULL;
        }

        repr->setAttribute("inkscape:groupmode", value);
    }

    SPLPEItem::write(xml_doc, repr, flags);

    return repr;
}

Geom::OptRect SPGroup::bbox(Geom::Affine const &transform, SPItem::BBoxType bboxtype)
{
    Geom::OptRect bbox;

    GSList *l = this->childList(false, SPObject::ActionBBox);

    while (l) {
        SPObject *o = SP_OBJECT (l->data);

        if (SP_IS_ITEM(o) && !SP_ITEM(o)->isHidden()) {
            SPItem *child = SP_ITEM(o);
            Geom::Affine const ct(child->transform * transform);
            bbox |= child->bounds(bboxtype, ct);
        }

        l = g_slist_remove (l, o);
    }

    return bbox;
}

void SPGroup::print(SPPrintContext *ctx) {
    GSList *l = g_slist_reverse(this->childList(false));

    while (l) {
        SPObject *o = SP_OBJECT (l->data);

        if (SP_IS_ITEM(o)) {
            SP_ITEM(o)->invoke_print (ctx);
        }

        l = g_slist_remove (l, o);
    }
}

const char *SPGroup::displayName() {
    return _("Group");
}

gchar *SPGroup::description() {
    gint len = this->getItemCount();
    return g_strdup_printf(
        ngettext(_("of <b>%d</b> object"), _("of <b>%d</b> objects"), len), len);
}

void SPGroup::set(unsigned int key, gchar const* value) {
    switch (key) {
        case SP_ATTR_INKSCAPE_GROUPMODE:
            if ( value && !strcmp(value, "layer") ) {
                this->setLayerMode(SPGroup::LAYER);
            } else if ( value && !strcmp(value, "maskhelper") ) {
                this->setLayerMode(SPGroup::MASK_HELPER);
            } else {
                this->setLayerMode(SPGroup::GROUP);
            }
            break;

        default:
            SPLPEItem::set(key, value);
            break;
    }
}

Inkscape::DrawingItem *SPGroup::show (Inkscape::Drawing &drawing, unsigned int key, unsigned int flags) {
    Inkscape::DrawingGroup *ai;

    ai = new Inkscape::DrawingGroup(drawing);
    ai->setPickChildren(this->effectiveLayerMode(key) == SPGroup::LAYER);
    ai->setStyle(this->style);

    this->_showChildren(drawing, ai, key, flags);
    return ai;
}

void SPGroup::hide (unsigned int key) {
    SPItem * child;

    GSList *l = g_slist_reverse(this->childList(false, SPObject::ActionShow));

    while (l) {
        SPObject *o = SP_OBJECT (l->data);

        if (SP_IS_ITEM (o)) {
            child = SP_ITEM (o);
            child->invoke_hide (key);
        }

        l = g_slist_remove (l, o);
    }

//    SPLPEItem::onHide(key);
}


void SPGroup::snappoints(std::vector<Inkscape::SnapCandidatePoint> &p, Inkscape::SnapPreferences const *snapprefs) {
    for ( SPObject const *o = this->firstChild(); o; o = o->getNext() )
    {
        if (SP_IS_ITEM(o)) {
            SP_ITEM(o)->getSnappoints(p, snapprefs);
        }
    }
}


void
sp_item_group_ungroup (SPGroup *group, GSList **children, bool do_done)
{
    g_return_if_fail (group != NULL);
    g_return_if_fail (SP_IS_GROUP (group));

    SPDocument *doc = group->document;
    SPRoot *root = doc->getRoot();
    SPObject *defs = root->defs;

    SPItem *gitem = group;
    Inkscape::XML::Node *grepr = gitem->getRepr();

    g_return_if_fail (!strcmp (grepr->name(), "svg:g")
                   || !strcmp (grepr->name(), "svg:a")
                   || !strcmp (grepr->name(), "svg:switch")
                   || !strcmp (grepr->name(), "svg:svg"));

    // this converts the gradient/pattern fill/stroke on the group, if any, to userSpaceOnUse
    gitem->adjust_paint_recursive (Geom::identity(), Geom::identity(), false);

    SPItem *pitem = SP_ITEM(gitem->parent);
    Inkscape::XML::Node *prepr = pitem->getRepr();

	if (SP_IS_BOX3D(gitem)) {
		group = box3d_convert_to_group(SP_BOX3D(gitem));
		gitem = group;
	}

	sp_lpe_item_remove_all_path_effects(SP_LPE_ITEM(group), false);

    /* Step 1 - generate lists of children objects */
    GSList *items = NULL;
    GSList *objects = NULL;
    for (SPObject *child = group->firstChild() ; child; child = child->getNext() ) {

        if (SP_IS_ITEM (child)) {

            SPItem *citem = SP_ITEM (child);

            /* Merging of style */
            // this converts the gradient/pattern fill/stroke, if any, to userSpaceOnUse; we need to do
            // it here _before_ the new transform is set, so as to use the pre-transform bbox
            citem->adjust_paint_recursive (Geom::identity(), Geom::identity(), false);

            sp_style_merge_from_dying_parent(child->style, gitem->style);
            /*
             * fixme: We currently make no allowance for the case where child is cloned
             * and the group has any style settings.
             *
             * (This should never occur with documents created solely with the current
             * version of inkscape without using the XML editor: we usually apply group
             * style changes to children rather than to the group itself.)
             *
             * If the group has no style settings, then
             * sp_style_merge_from_dying_parent should be a no-op.  Otherwise (i.e. if
             * we change the child's style to compensate for its parent going away)
             * then those changes will typically be reflected in any clones of child,
             * whereas we'd prefer for Ungroup not to affect the visual appearance.
             *
             * The only way of preserving styling appearance in general is for child to
             * be put into a new group -- a somewhat surprising response to an Ungroup
             * command.  We could add a new groupmode:transparent that would mostly
             * hide the existence of such groups from the user (i.e. editing behaves as
             * if the transparent group's children weren't in a group), though that's
             * extra complication & maintenance burden and this case is rare.
             */

            child->updateRepr();

            Inkscape::XML::Node *nrepr = child->getRepr()->duplicate(prepr->document());

            // Merging transform
            Geom::Affine ctrans;
            Geom::Affine const g(gitem->transform);
            if (SP_IS_USE(citem) && sp_use_get_original (SP_USE(citem)) &&
                sp_use_get_original( SP_USE(citem) )->parent == SP_OBJECT(group)) {
                // make sure a clone's effective transform is the same as was under group
                ctrans = g.inverse() * citem->transform * g;
            } else {
                // We should not apply the group's transformation to both a linked offset AND to its source
                if (SP_IS_OFFSET(citem)) { // Do we have an offset at hand (whether it's dynamic or linked)?
                    SPItem *source = sp_offset_get_source(SP_OFFSET(citem));
                    // When dealing with a chain of linked offsets, the transformation of an offset will be
                    // tied to the transformation of the top-most source, not to any of the intermediate
                    // offsets. So let's find the top-most source
                    while (source != NULL && SP_IS_OFFSET(source)) {
                        source = sp_offset_get_source(SP_OFFSET(source));
                    }
                    if (source != NULL && // If true then we must be dealing with a linked offset ...
                        group->isAncestorOf(source) == false) { // ... of which the source is not in the same group
                        ctrans = citem->transform * g; // then we should apply the transformation of the group to the offset
                    } else {
                        ctrans = citem->transform;
                    }
                } else {
                    ctrans = citem->transform * g;
                }
            }

            // FIXME: constructing a transform that would fully preserve the appearance of a
            // textpath if it is ungrouped with its path seems to be impossible in general
            // case. E.g. if the group was squeezed, to keep the ungrouped textpath squeezed
            // as well, we'll need to relink it to some "virtual" path which is inversely
            // stretched relative to the actual path, and then squeeze the textpath back so it
            // would both fit the actual path _and_ be squeezed as before. It's a bummer.

            // This is just a way to temporarily remember the transform in repr. When repr is
            // reattached outside of the group, the transform will be written more properly
            // (i.e. optimized into the object if the corresponding preference is set)
            gchar *affinestr=sp_svg_transform_write(ctrans);
            nrepr->setAttribute("transform", affinestr);
            g_free(affinestr);

            items = g_slist_prepend (items, nrepr);

        } else {
            Inkscape::XML::Node *nrepr = child->getRepr()->duplicate(prepr->document());
            objects = g_slist_prepend (objects, nrepr);
        }
    }

    /* Step 2 - clear group */
    // remember the position of the group
    gint pos = group->getRepr()->position();

    // the group is leaving forever, no heir, clones should take note; its children however are going to reemerge
    group->deleteObject(true, false);

    /* Step 3 - add nonitems */
    if (objects) {
        Inkscape::XML::Node *last_def = defs->getRepr()->lastChild();
        while (objects) {
            Inkscape::XML::Node *repr = (Inkscape::XML::Node *) objects->data;
            if (!sp_repr_is_meta_element(repr)) {
                defs->getRepr()->addChild(repr, last_def);
            }
            Inkscape::GC::release(repr);
            objects = g_slist_remove (objects, objects->data);
        }
    }

    /* Step 4 - add items */
    while (items) {
        Inkscape::XML::Node *repr = (Inkscape::XML::Node *) items->data;
        // add item
        prepr->appendChild(repr);
        // restore position; since the items list was prepended (i.e. reverse), we now add
        // all children at the same pos, which inverts the order once again
        repr->setPosition(pos > 0 ? pos : 0);

        // fill in the children list if non-null
        SPItem *item = static_cast<SPItem *>(doc->getObjectByRepr(repr));

        item->doWriteTransform(repr, item->transform, NULL, false);

        Inkscape::GC::release(repr);
        if (children && SP_IS_ITEM(item)) {
            *children = g_slist_prepend(*children, item);
        }

        items = g_slist_remove (items, items->data);
    }

    if (do_done) {
        DocumentUndo::done(doc, SP_VERB_NONE, _("Ungroup"));
    }
}

/*
 * some API for list aspect of SPGroup
 */

GSList *sp_item_group_item_list(SPGroup * group)
{
    g_return_val_if_fail(group != NULL, NULL);
    g_return_val_if_fail(SP_IS_GROUP(group), NULL);

    GSList *s = NULL;

    for (SPObject *o = group->firstChild() ; o ; o = o->getNext() ) {
        if ( SP_IS_ITEM(o) ) {
            s = g_slist_prepend(s, o);
        }
    }

    return g_slist_reverse (s);
}

SPObject *sp_item_group_get_child_by_name(SPGroup *group, SPObject *ref, const gchar *name)
{
    SPObject *child = (ref) ? ref->getNext() : group->firstChild();
    while ( child && strcmp(child->getRepr()->name(), name) ) {
        child = child->getNext();
    }
    return child;
}

void SPGroup::setLayerMode(LayerMode mode) {
    if ( _layer_mode != mode ) {
        if ( mode == LAYER ) {
            this->document->addResource("layer", this);
        } else if ( _layer_mode == LAYER ) {
            this->document->removeResource("layer", this);
        }
        _layer_mode = mode;
        _updateLayerMode();
    }
}

SPGroup::LayerMode SPGroup::layerDisplayMode(unsigned int dkey) const {
    std::map<unsigned int, LayerMode>::const_iterator iter;
    iter = _display_modes.find(dkey);
    if ( iter != _display_modes.end() ) {
        return (*iter).second;
    } else {
        return GROUP;
    }
}

void SPGroup::setLayerDisplayMode(unsigned int dkey, SPGroup::LayerMode mode) {
    if ( layerDisplayMode(dkey) != mode ) {
        _display_modes[dkey] = mode;
        _updateLayerMode(dkey);
    }
}

void SPGroup::_updateLayerMode(unsigned int display_key) {
    SPItemView *view;
    for ( view = this->display ; view ; view = view->next ) {
        if ( !display_key || view->key == display_key ) {
            Inkscape::DrawingGroup *g = dynamic_cast<Inkscape::DrawingGroup *>(view->arenaitem);
            if (g) {
                g->setPickChildren(effectiveLayerMode(view->key) == SPGroup::LAYER);
            }
        }
    }
}

void SPGroup::translateChildItems(Geom::Translate const &tr)
{
    if ( hasChildren() ) {
        for (SPObject *o = firstChild() ; o ; o = o->getNext() ) {
            if ( SP_IS_ITEM(o) ) {
                sp_item_move_rel(reinterpret_cast<SPItem *>(o), tr);
            }
        }
    }
}

// Recursively scale child items around a point
void SPGroup::scaleChildItemsRec(Geom::Scale const &sc, Geom::Point const &p)
{
    if ( hasChildren() ) {
        for (SPObject *o = firstChild() ; o ; o = o->getNext() ) {
            if ( SP_IS_ITEM(o) ) {
                if (SP_IS_GROUP(o) && !SP_IS_BOX3D(o)) {
                    SP_GROUP(o)->scaleChildItemsRec(sc, p);
                } else {
                    SPItem *item = SP_ITEM(o);
                    Geom::OptRect bbox = item->desktopVisualBounds();
                    if (bbox) {
                        // Scale item
                        Geom::Translate const s(p);
                        Geom::Affine final = s.inverse() * sc * s;
                        
                        Geom::Point old_center(0,0);
                        if (item->isCenterSet()) {
                            old_center = item->getCenter();
                        }
                        
                        gchar const *conn_type = NULL;
                        if (SP_IS_TEXT_TEXTPATH(item)) {
                            SP_TEXT(item)->optimizeTextpathText();
                        } else if (SP_IS_FLOWTEXT(item)) {
                            SP_FLOWTEXT(item)->optimizeScaledText();
                        } else if (SP_IS_BOX3D(item)) {
                            // Force recalculation from perspective
                            box3d_position_set(SP_BOX3D(item));
                        } else if (item->getAttribute("inkscape:connector-type") != NULL
                            && (item->getAttribute("inkscape:connection-start") == NULL
                                || item->getAttribute("inkscape:connection-end") == NULL)) {
                            // Remove and store connector type for transform if disconnected
                            conn_type = item->getAttribute("inkscape:connector-type");
                            item->removeAttribute("inkscape:connector-type");
                        }
                        
                        if (SP_IS_PERSP3D(item)) {
                            persp3d_apply_affine_transformation(SP_PERSP3D(item), final);
                        } else if ((SP_IS_TEXT_TEXTPATH(item) || SP_IS_FLOWTEXT(item)) && !item->transform.isIdentity()) {
                            // Save and reset current transform
                            Geom::Affine tmp(item->transform);
                            item->transform = Geom::Affine();
                            // Apply scale
                            item->set_i2d_affine(item->i2dt_affine() * sc);
                            item->doWriteTransform(item->getRepr(), item->transform, NULL, true);
                            // Scale translation and restore original transform
                            tmp[4] *= sc[0];
                            tmp[5] *= sc[1];
                            item->doWriteTransform(item->getRepr(), tmp, NULL, true);
                        } else if (SP_IS_USE(item)) {
                            // calculate the matrix we need to apply to the clone
                            // to cancel its induced transform from its original
                            Geom::Affine move = final.inverse() * item->transform * final;
                            item->doWriteTransform(item->getRepr(), move, &move, true);
                        } else {
                            item->set_i2d_affine(item->i2dt_affine() * final);
                            item->doWriteTransform(item->getRepr(), item->transform, NULL, true);
                        }
                        
                        if (conn_type != NULL) {
                            item->setAttribute("inkscape:connector-type", conn_type);
                        }
                        
                        if (item->isCenterSet() && !(final.isTranslation() || final.isIdentity())) {
                            item->setCenter(old_center * final);
                            item->updateRepr();
                        }
                    }
                }
            }
        }
    }
}

gint SPGroup::getItemCount() {
    gint len = 0;
    for (SPObject *o = this->firstChild() ; o ; o = o->getNext() ) {
        if (SP_IS_ITEM(o)) {
            len++;
        }
    }

    return len;
}

void SPGroup::_showChildren (Inkscape::Drawing &drawing, Inkscape::DrawingItem *ai, unsigned int key, unsigned int flags) {
    Inkscape::DrawingItem *ac = NULL;
    SPItem * child = NULL;
    GSList *l = g_slist_reverse(this->childList(false, SPObject::ActionShow));
    while (l) {
        SPObject *o = SP_OBJECT (l->data);
        if (SP_IS_ITEM (o)) {
            child = SP_ITEM (o);
            ac = child->invoke_show (drawing, key, flags);
            if (ac) {
                ai->appendChild(ac);
            }
        }
        l = g_slist_remove (l, o);
    }
}

void SPGroup::update_patheffect(bool write) {
#ifdef GROUP_VERBOSE
    g_message("sp_group_update_patheffect: %p\n", lpeitem);
#endif

    GSList const *item_list = sp_item_group_item_list(this);

    for ( GSList const *iter = item_list; iter; iter = iter->next ) {
        SPObject *subitem = static_cast<SPObject *>(iter->data);

        if (SP_IS_LPE_ITEM(subitem)) {
        	((SPLPEItem*)subitem)->update_patheffect(write);
        }
    }

    if (sp_lpe_item_has_path_effect(this) && sp_lpe_item_path_effects_enabled(this)) {
        for (PathEffectList::iterator it = this->path_effect_list->begin(); it != this->path_effect_list->end(); it++)
        {
            LivePathEffectObject *lpeobj = (*it)->lpeobject;

            if (lpeobj && lpeobj->get_lpe()) {
                lpeobj->get_lpe()->doBeforeEffect(this);
            }
        }

        sp_group_perform_patheffect(this, this, write);
    }
}

static void
sp_group_perform_patheffect(SPGroup *group, SPGroup *topgroup, bool write)
{
    GSList const *item_list = sp_item_group_item_list(SP_GROUP(group));

    for ( GSList const *iter = item_list; iter; iter = iter->next ) {
        SPObject *subitem = static_cast<SPObject *>(iter->data);

        if (SP_IS_GROUP(subitem)) {
            sp_group_perform_patheffect(SP_GROUP(subitem), topgroup, write);
        } else if (SP_IS_SHAPE(subitem)) {
            SPCurve * c = NULL;

            if (SP_IS_PATH(subitem)) {
                c = SP_PATH(subitem)->get_original_curve();
            } else {
                c = SP_SHAPE(subitem)->getCurve();
            }

            // only run LPEs when the shape has a curve defined
            if (c) {
                c->transform(i2anc_affine(subitem, topgroup));
                sp_lpe_item_perform_path_effect(SP_LPE_ITEM(topgroup), c);
                c->transform(i2anc_affine(subitem, topgroup).inverse());
                SP_SHAPE(subitem)->setCurve(c, TRUE);

                if (write) {
                    Inkscape::XML::Node *repr = subitem->getRepr();
                    gchar *str = sp_svg_write_path(c->get_pathvector());
                    repr->setAttribute("d", str);
#ifdef GROUP_VERBOSE
g_message("sp_group_perform_patheffect writes 'd' attribute");
#endif
                    g_free(str);
                }

                c->unref();
            }
        }
    }
}

/*
  Local Variables:
  mode:c++
  c-file-style:"stroustrup"
  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
  indent-tabs-mode:nil
  fill-column:99
  End:
*/
// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :
