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// This file contains the declarations of the GetRootFeature(),
// VisitFeatureHierarchy() functions and FeatureVisitor base class.

#ifndef KML_ENGINE_FEATURE_VISITOR_H__
#define KML_ENGINE_FEATURE_VISITOR_H__

#include "kml/dom.h"

namespace kmlengine {

// This returns the root Feature of the given KML hierarchy.  If root is
// neither of Type_Kml nor Type_Feature NULL is returned.
const kmldom::FeaturePtr GetRootFeature(const kmldom::ElementPtr& root);

// This is the base class for use with VisitFeatureHierarchy.  Derive your own
// class and implement VisitFeature and pass the instance of your class to
// VisitFeatureHierarchy
class FeatureVisitor {
 public:
  virtual ~FeatureVisitor() {}
  virtual void VisitFeature(const kmldom::FeaturePtr& feature) {}
};

// Visit the Feature hierarchy rooted at feature calling the VisitFeature()
// method of the given FeatureVisitor in depth-first order.
void VisitFeatureHierarchy(const kmldom::FeaturePtr& feature,
                           FeatureVisitor& feature_visitor);

}  // end namespace kmlengine

#endif  // KML_ENGINE_FEATURE_VISITOR_H__