#include "config.h"
#include "XPathPath.h"
#include "Document.h"
#include "XPathPredicate.h"
#include "XPathStep.h"
namespace WebCore {
namespace XPath {
Filter::Filter(std::unique_ptr<Expression> expression, Vector<std::unique_ptr<Expression>> predicates)
: m_expression(WTF::move(expression)), m_predicates(WTF::move(predicates))
{
setIsContextNodeSensitive(m_expression->isContextNodeSensitive());
setIsContextPositionSensitive(m_expression->isContextPositionSensitive());
setIsContextSizeSensitive(m_expression->isContextSizeSensitive());
}
Value Filter::evaluate() const
{
Value result = m_expression->evaluate();
NodeSet& nodes = result.modifiableNodeSet();
nodes.sort();
EvaluationContext& evaluationContext = Expression::evaluationContext();
for (unsigned i = 0; i < m_predicates.size(); i++) {
NodeSet newNodes;
evaluationContext.size = nodes.size();
evaluationContext.position = 0;
for (unsigned j = 0; j < nodes.size(); j++) {
Node* node = nodes[j];
evaluationContext.node = node;
++evaluationContext.position;
if (evaluatePredicate(*m_predicates[i]))
newNodes.append(node);
}
nodes = WTF::move(newNodes);
}
return result;
}
LocationPath::LocationPath()
: m_isAbsolute(false)
{
setIsContextNodeSensitive(true);
}
Value LocationPath::evaluate() const
{
EvaluationContext& evaluationContext = Expression::evaluationContext();
EvaluationContext backupContext = evaluationContext;
Node* context = evaluationContext.node.get();
if (m_isAbsolute && !context->isDocumentNode()) {
if (context->inDocument())
context = context->ownerDocument();
else
context = context->highestAncestor();
}
NodeSet nodes;
nodes.append(context);
evaluate(nodes);
evaluationContext = backupContext;
return Value(WTF::move(nodes));
}
void LocationPath::evaluate(NodeSet& nodes) const
{
bool resultIsSorted = nodes.isSorted();
for (unsigned i = 0; i < m_steps.size(); i++) {
Step& step = *m_steps[i];
NodeSet newNodes;
HashSet<Node*> newNodesSet;
bool needToCheckForDuplicateNodes = !nodes.subtreesAreDisjoint() || (step.axis() != Step::ChildAxis && step.axis() != Step::SelfAxis
&& step.axis() != Step::DescendantAxis && step.axis() != Step::DescendantOrSelfAxis && step.axis() != Step::AttributeAxis);
if (needToCheckForDuplicateNodes)
resultIsSorted = false;
if (nodes.subtreesAreDisjoint() && (step.axis() == Step::ChildAxis || step.axis() == Step::SelfAxis))
newNodes.markSubtreesDisjoint(true);
for (unsigned j = 0; j < nodes.size(); j++) {
NodeSet matches;
step.evaluate(*nodes[j], matches);
if (!matches.isSorted())
resultIsSorted = false;
for (size_t nodeIndex = 0; nodeIndex < matches.size(); ++nodeIndex) {
Node* node = matches[nodeIndex];
if (!needToCheckForDuplicateNodes || newNodesSet.add(node).isNewEntry)
newNodes.append(node);
}
}
nodes = WTF::move(newNodes);
}
nodes.markSorted(resultIsSorted);
}
void LocationPath::appendStep(std::unique_ptr<Step> step)
{
unsigned stepCount = m_steps.size();
if (stepCount) {
bool dropSecondStep;
optimizeStepPair(*m_steps[stepCount - 1], *step, dropSecondStep);
if (dropSecondStep)
return;
}
step->optimize();
m_steps.append(WTF::move(step));
}
void LocationPath::prependStep(std::unique_ptr<Step> step)
{
if (m_steps.size()) {
bool dropSecondStep;
optimizeStepPair(*step, *m_steps[0], dropSecondStep);
if (dropSecondStep) {
m_steps[0] = WTF::move(step);
return;
}
}
step->optimize();
m_steps.insert(0, WTF::move(step));
}
Path::Path(std::unique_ptr<Expression> filter, std::unique_ptr<LocationPath> path)
: m_filter(WTF::move(filter))
, m_path(WTF::move(path))
{
setIsContextNodeSensitive(m_filter->isContextNodeSensitive());
setIsContextPositionSensitive(m_filter->isContextPositionSensitive());
setIsContextSizeSensitive(m_filter->isContextSizeSensitive());
}
Value Path::evaluate() const
{
Value result = m_filter->evaluate();
NodeSet& nodes = result.modifiableNodeSet();
m_path->evaluate(nodes);
return result;
}
}
}