/* -*- mode: C -*-  */
/* 
   IGraph library.
   Copyright (C) 2006-2012  Gabor Csardi <csardi.gabor@gmail.com>
   334 Harvard st, Cambridge MA, 02139 USA
   
   This program 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; either version 2 of the License, or
   (at your option) any later version.
   
   This program 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 this program; if not, write to the Free Software
   Foundation, Inc.,  51 Franklin Street, Fifth Floor, Boston, MA 
   02110-1301 USA

*/

#include <igraph.h>
#include <math.h>
#include <stdlib.h>

int main() {
  igraph_t g, extd_g;
  igraph_matrix_t coords;
  igraph_vector_t edgelist, extd_edgelist, extd_to_orig_eids;
  igraph_vector_t layers;

  igraph_matrix_init(&coords, 0, 0);
  igraph_vector_init(&extd_to_orig_eids, 0);

  /* Layout on simple graph with predefined layers */
  igraph_vector_init_int_end(&layers, -1, 0,1,1,2,3,3,4,4,5, -1);
  igraph_vector_init_int_end(&edgelist, -1,
          0,1, 0,2, 0,3, 1,2, 2,2, 1,4, 2,5, 4,6, 5,7, 6,8, 7,8,
          3,8, 8,1, 8,2, -1);
  igraph_create(&g, &edgelist, 0, 1);

  igraph_layout_sugiyama(&g, &coords, 0, 0, &layers,
          /* hgap = */ 1,
          /* vgap = */ 1,
          /* maxiter = */ 100,
          /* weights = */ 0);
  igraph_matrix_print(&coords);
  printf("===\n");

  /* Same, but this time also return the extended graph */
  igraph_layout_sugiyama(&g, &coords, &extd_g, &extd_to_orig_eids, &layers,
          /* hgap = */ 1,
          /* vgap = */ 1,
          /* maxiter = */ 100,
          /* weights = */ 0);
  igraph_matrix_print(&coords);
  printf("===\n");
  igraph_vector_init(&extd_edgelist, 0);
  igraph_get_edgelist(&extd_g, &extd_edgelist, 0);
  igraph_vector_print(&extd_edgelist);
  igraph_vector_destroy(&extd_edgelist);
  igraph_destroy(&extd_g);
  printf("===\n");
  igraph_vector_print(&extd_to_orig_eids);
  printf("===\n");

  igraph_vector_destroy(&layers);

  /* Same, but with automatic layering */
  igraph_layout_sugiyama(&g, &coords, 0, 0, 0,
          /* hgap = */ 1,
          /* vgap = */ 1,
          /* maxiter = */ 100,
          /* weights = */ 0);
  igraph_matrix_print(&coords);
  printf("===\n");

  /* Layering with gaps in it */
  igraph_vector_init_int_end(&layers, -1, 0,2,2,4,6,6,12,12,15, -1);
  igraph_layout_sugiyama(&g, &coords, 0, 0, &layers,
          /* hgap = */ 1,
          /* vgap = */ 1,
          /* maxiter = */ 100,
          /* weights = */ 0);
  igraph_matrix_print(&coords);
  igraph_vector_destroy(&layers);
  printf("===\n");

  igraph_vector_destroy(&edgelist);
  igraph_matrix_destroy(&coords);
  igraph_vector_destroy(&extd_to_orig_eids);
  igraph_destroy(&g);

  return 0;
}