/**
* Copyright 2010 Bazaarvoice, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* @author J. Ryan Stinnett (ryan.stinnett@bazaarvoice.com)
*/
package com.bazaarvoice.jless.ast.node;
import com.bazaarvoice.jless.ast.util.NodeTreeUtils;
import com.bazaarvoice.jless.ast.visitor.InclusiveNodeVisitor;
import com.bazaarvoice.jless.ast.visitor.NodeAdditionVisitor;
import com.bazaarvoice.jless.ast.visitor.NodeNavigationVisitor;
public class SelectorNode extends InternalNode {
public SelectorNode() {
super();
setAdditionVisitor();
}
public SelectorNode(Node child) {
this();
addChild(child);
}
private void setAdditionVisitor() {
setAdditionVisitor(new InclusiveNodeVisitor() {
/**
* Absorb all children of the given selector. This assumes that cloning is not necessary.
*/
@Override
public boolean add(SelectorNode selector) {
// If the first segment is a universal ("*") segment, it must remain first in the list
SelectorSegmentNode sourceSegment = NodeTreeUtils.getFirstChild(selector, SelectorSegmentNode.class);
if (sourceSegment.isUniversal()) {
// If the first destination segment is not a sub-element selector and it has no combinator,
// switch it to the descendant combinator before absorbing the universal segment.
setCombinatorIfNotSubElement(SelectorNode.this);
// Add the universal HTML segment at the front of the list
addChild(0, sourceSegment);
}
// If the first source segment is not a sub-element selector and it has no combinator,
// switch it to the descendant combinator before absorbing the segments.
setCombinatorIfNotSubElement(selector);
NodeTreeUtils.moveChildren(selector, SelectorNode.this);
return false; // Don't add the original selector itself
}
});
}
private void setCombinatorIfNotSubElement(SelectorNode selector) {
SelectorSegmentNode sourceSegment = NodeTreeUtils.getFirstChild(selector, SelectorSegmentNode.class);
if (!sourceSegment.isSubElementSelector() && sourceSegment.getCombinator().equals(SelectorSegmentNode.NO_COMBINATOR)) {
sourceSegment.setCombinator(SelectorSegmentNode.DESCENDANT_COMBINATOR);
}
}
@Override
protected boolean add(NodeAdditionVisitor visitor) {
return visitor.add(this);
}
@Override
protected boolean enter(NodeNavigationVisitor visitor) {
return visitor.enter(this);
}
@Override
protected boolean exit(NodeNavigationVisitor visitor) {
return visitor.exit(this);
}
@Override
protected boolean visitInvisible(NodeNavigationVisitor visitor) {
return visitor.visitInvisible(this);
}
/**
* The internal state of this node will be rebuilt as cloned children are added by the super class.
*/
@Override
public SelectorNode clone() {
return (SelectorNode) super.clone();
}
/**
* Recreate internal state before children are cloned.
*/
@Override
protected void cloneChildren(InternalNode node) {
SelectorNode selector = (SelectorNode) node;
// Reset internal state
selector.setAdditionVisitor();
super.cloneChildren(node);
}
}