grid.H

# ifndef GRID_H
# define GRID_H

namespace Aleph 
{ 

template <class GT>
struct Default_Operation_On_Node
{
  void operator () (GT &, typename GT::Node *, const size_t &, const size_t &) { /* Empty */ }
};

template <class GT>
struct Default_Operation_On_Arc
{
  void operator () (GT &, typename GT::Arc *, const size_t &, const size_t &) { /* Empty */ }
};

template <
          class GT,
          class Operation_On_Node = Default_Operation_On_Node<GT>,
          class Operation_On_Arc = Default_Operation_On_Arc<GT>
         >
class Build_Grid
{
public:
  void operator () (GT & g, const size_t & width, const size_t & height)
  {
    if (g.get_num_nodes() != 0)
      throw std::domain_error("There is nodes in graph");

    if (width < 2 or height < 2)
      throw std::length_error("The minimun size must be 2 x 2");

    typename GT::Node *** map = new typename GT::Node **[height];
    for (size_t i = 0; i < height; ++i)
      {
        try
          {
            map[i] = new typename GT::Node *[width];
            for (size_t j = 0; j < width; ++j)
              {
                typename GT::Node * n = g.insert_node(typename GT::Node_Type());
                Operation_On_Node()(g, n, i, j);
                map[i][j] = n;
                if (j > 0) //Conecta con el nodo a su izquierda
                  {
                    typename GT::Arc * a = g.insert_arc(n, map[i][j - 1]);
                    Operation_On_Arc()(g, a, i, j);
                  }
                if (i > 0) //Conecta con el nodo que esta arriba
                  {
                    typename GT::Arc * a = g.insert_arc(n, map[i - 1][j]);
                    Operation_On_Arc()(g, a, i, j);
                  }
                if (i > 0 and j > 0) //Conecta con el nodo que esta arriba y a la izquierda
                  {
                    typename GT::Arc * a = g.insert_arc(n, map[i - 1][j - 1]);
                    Operation_On_Arc()(g, a, i, j);
                  }
                if (j + 1 < width and i > 0) //Conecta con el nodo que esta arriba y a la derecha
                  {
                    typename GT::Arc * a = g.insert_arc(n, map[i - 1][j + 1]);
                    Operation_On_Arc()(g, a, i, j);
                  }
              }
          }
        catch (...)
          {
            for (size_t k = i - 1; k >= 0; --k)
              delete [] map[k];
            delete [] map;
            clear_graph(g);
            throw;
          }
      }

    for (size_t i = 0; i < height; ++i)
      delete [] map[i];
    delete [] map;
  }
};

}

# endif