tree.hh

// Copyright (C) 2007, 2008, 2009 EPITA Research and Development Laboratory (LRDE)
//
// This file is part of Olena.
//
// Olena is free software: you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the Free
// Software Foundation, version 2 of the License.
//
// Olena is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Olena.  If not, see <http://www.gnu.org/licenses/>.
//
// As a special exception, you may use this file as part of a free
// software project without restriction.  Specifically, if other files
// instantiate templates or use macros or inline functions from this
// file, or you compile this file and link it with other files to produce
// an executable, this file does not by itself cause the resulting
// executable to be covered by the GNU General Public License.  This
// exception does not however invalidate any other reasons why the
// executable file might be covered by the GNU General Public License.

#ifndef MLN_UTIL_TREE_HH
# define MLN_UTIL_TREE_HH

# include <vector>
# include <algorithm>
# include <iostream>
# include <algorithm>
# include <mln/core/contract.hh>

namespace mln
{

  namespace util
  {

    template <typename T> class tree_node;
    template <typename T> class tree;
    template <typename T> class branch;


    template <typename T>
    class tree_node
    {
    public:

      typedef std::vector< tree_node<T>* > children_t;

      tree_node();

      tree_node(T elt);


      T& elt();

      const T& elt() const;


      children_t& children();


      const children_t& children() const;


      tree_node<T>* parent();


      tree_node<T>* add_child(T elt);

      tree_node<T>* add_child(tree_node<T>* tree_node);

      void set_parent(tree_node<T>* parent);

      tree_node<T>* delete_tree_node();

      void print(std::ostream& ostr, int level = 0);

      bool check_consistency();


      tree_node<T>* search(T& elt);

      int  search_rec(tree_node<T>** res, T& elt);

    private:

      T elt_;

      tree_node<T>* parent_;

      std::vector< tree_node<T>* > child_;
    };



    template <typename T>
    class tree
    {
    public:

      typedef tree_node<T> tree_node_t;

      tree();

      tree(tree_node<T>* root);


      tree_node<T>* root();

      branch<T> main_branch();

      bool check_consistency();


      void add_tree_up (T& elt);

      void add_tree_down (T& elt);

    private:

      tree_node<T>* root_;
    };


    template <typename T>
    class branch
    {
    public:

      branch(tree<T>& tree, tree_node<T>& apex);

      tree_node<T>& apex();

      tree<T>& util_tree();

    private:
      util::tree<T>& tree_;

      tree_node<T>& apex_;
    };


# ifndef MLN_INCLUDE_ONLY

    template <typename T>
    inline
    tree<T>::tree()
      : root_ (0)
    {
    }

    template <typename T>
    inline
    tree<T>::tree(tree_node<T>* root)
      : root_ (root)
    {
      mln_assertion (root != 0);
    }

    template <typename T>
    inline
    tree_node<T>*
    tree<T>::root()
    {
      return root_;
    }

    template <typename T>
    inline
    branch<T>
    tree<T>::main_branch()
    {
      return branch<T>(*this, *root());
    }

    template <typename T>
    inline
    void
    tree<T>::add_tree_up(T& elt)
    {
      tree_node<T>* n = new tree_node<T> (elt);
      root_->set_parent(n);
      n->children().push_back (root_);
      root_ = n;
    }

    template <typename T>
    inline
    void
    tree<T>::add_tree_down(T& elt)
    {
      tree_node<T>* n = new tree_node<T> (elt);
      root_->child_.push_back (n);
    }


    template <typename T>
    inline
    bool
    tree<T>::check_consistency()
    {
      return root()->check_consistency ();
    }

    template <typename T>
    inline
    tree_node<T>::tree_node()
      : parent_ (0)
    {
    }

    template <typename T>
    inline
    tree_node<T>::tree_node(T elt)
      : elt_ (elt),
        parent_ (0)
    {
    }

    template <typename T>
    inline
    const T&
    tree_node<T>::elt() const
    {
      return elt_;
    }

    template <typename T>
    inline
    T&
    tree_node<T>::elt()
    {
      return elt_;
    }


    template <typename T>
    inline
    std::vector< tree_node<T>* >&
    tree_node<T>::children()
    {
      return child_;
    }

    template <typename T>
    inline
    const std::vector< tree_node<T>* >&
    tree_node<T>::children() const
    {
      return child_;
    }

    template <typename T>
    inline
    tree_node<T>*
    tree_node<T>::add_child(T elt)
    {
      tree_node<T>* s = new tree_node<T>(elt);

      s->parent_ = this;
      this->child_.push_back(s);
      return s;
    }


    template <typename T>
    inline
    tree_node<T>*
    tree_node<T>::add_child(tree_node<T>* tree_node)
    {
      if (tree_node->parent_)
        {
          for (typename std::vector<util::tree_node<T>* >::iterator it = tree_node->parent()->children().begin();
               it != tree_node->parent()->children().end(); ++it)
            if ((*it) == tree_node)
            {
              tree_node->parent()->children().erase(it);
              break;
            }
        }
      tree_node->parent_ = this;
      this->children().push_back(tree_node);
      return tree_node;
    }

    template <typename T>
    inline
    tree_node<T>*
    tree_node<T>::delete_tree_node()
    {
      mln_assertion(parent_ != 0);
      tree_node<T>* res = parent_;

      typename std::vector<tree_node<T>* >::iterator it = parent_->children().begin();
      for (; it < parent_->children().end(); ++it)
        if ((*it) == this)
          {
            parent_->children().erase(it);
            break;
          }

      for (typename std::vector<tree_node<T>* >::iterator it = this->child_.begin();
           it != this->child_.end(); ++it)
        parent_->add_child(*it);
      return (res);
    }

    template <typename T>
    inline
    void
    tree_node<T>::print(std::ostream& ostr, int level)
    {
      ostr << level << std::endl;

      ostr << " elt " << this->elt() << std::endl;


      for (typename std::vector<tree_node<T>* >::iterator it = this->child_.begin();
           it != this->child_.end(); ++it)
        {
          (*it)->print(level + 1);
        }
    }


    template <typename T>
    inline
    void
    tree_node<T>::set_parent(tree_node<T>* parent)
    {
      mln_assertion(parent != 0);
      parent_ = parent;
      parent->child_.push_back(this);
    }

    template <typename T>
    inline
    tree_node<T>*
    tree_node<T>::parent()
    {
      return parent_;
    }

    template <typename T>
    inline
    int
    tree_node<T>::search_rec(tree_node<T>** res, T& elt)
    {
      if (elt == this->elt_)
      {
        *res = this;
        return 1;
      }
      else
      {
        for (typename std::vector<tree_node<T>* >::iterator it = this->child_.begin();
             it != this->child_.end(); ++it)
        {
          if ((**it).search_rec(res, elt))
            return 1;
        }
      }
      return 0;
    }

    template <typename T>
    inline
    tree_node<T>*
    tree_node<T>::search(T& elt)
    {
      tree_node<T>* res = 0;

      if (search_rec(&res, elt))
        return res;
      return 0;
    }

    template <typename T>
    inline
    bool
    tree_node<T>::check_consistency()
    {
      for (typename std::vector<tree_node<T>* >::iterator it = this->child_.begin();
           it != this->child_.end(); ++it)
      {
        if ((**it).parent() != this)
          return false;

        if (!((**it).check_consistency()))
          return false;
      }
      return true;
    }


    // Branch methods
    template <typename T>
    inline
    branch<T>::branch(util::tree<T>& tree,
                      util::tree_node<T>& apex)
      : tree_(tree),
        apex_(apex)
    {
    }


    template <typename T>
    inline
    util::tree_node<T>&
    branch<T>::apex()
    {
      return apex_;
    }

    template <typename T>
    inline
    mln::util::tree<T>&
    branch<T>::util_tree()
    {
      return tree_;
    }

# endif // ! MLN_INCLUDE_ONLY

  } // end of namespace mln::util


} // end of namespace mln


#endif // ! MLN_UTIL_TREE_HH