PathIterator.h

/**************************************************************************
 * basf2 (Belle II Analysis Software Framework)                           *
 * Author: The Belle II Collaboration                                     *
 *                                                                        *
 * See git log for contributors and copyright holders.                    *
 * This file is licensed under LGPL-3.0, see LICENSE.md.                  *
 **************************************************************************/
 
#pragma once
 
#include <framework/core/Path.h>
#include <memory>
 
 
namespace Belle2 {
  class Module;
 
  class PathIterator {
  public:
    explicit PathIterator(const PathPtr& path) :
      m_path(path),
      m_iter(path->m_elements.begin()),
      m_end(path->m_elements.end()),
      m_parentIterator()
    {
      descendIfNecessary();
    }
 
    explicit PathIterator(const PathPtr& path, const PathIterator& parentIterator) :
      m_path(path),
      m_iter(path->m_elements.begin()),
      m_end(path->m_elements.end()),
      m_parentIterator(new PathIterator(parentIterator))
    {
      descendIfNecessary();
    }
 
    void next()
    {
      if (!isDone())
        ++m_iter;
      descendIfNecessary();
    }
 
    void descendIfNecessary()
    {
      if (!isDone() and dynamic_cast<Path*>(m_iter->get())) {
        //we're pointing to another Path
        *this = PathIterator(std::static_pointer_cast<Path>(*m_iter), *this);
      }
      //check _afterwards_ if we need to jump back up
      if (isDone() and m_parentIterator) {
        //jump back to parent iterator
        *this = *(m_parentIterator.get());
        next(); //go to next module
      }
    }
 
    bool isDone() const { return (m_iter == m_end); }
 
    Module* get() const { return dynamic_cast<Module*>(m_iter->get()); }
 
 
  private:
    PathPtr m_path; 
    std::list<std::shared_ptr<PathElement> >::const_iterator m_iter; 
    std::list<std::shared_ptr<PathElement> >::const_iterator m_end; 
    std::shared_ptr<PathIterator> m_parentIterator; 
  };
 
} // end namespace Belle2