/* -*- mode: C -*-  */
/* vim:set ts=2 sts=2 sw=2 et: */
/* 
   IGraph library.
   Copyright (C) 2006-2012  Gabor Csardi <csardi.gabor@gmail.com>
   334 Harvard street, 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>

void show_results(igraph_t *g, igraph_vector_t *membership, igraph_matrix_t *memberships, igraph_vector_t *modularity, FILE* f) {
  long int i, j, no_of_nodes = igraph_vcount(g);

  j=igraph_vector_which_max(modularity);
  for (i=0; i<igraph_vector_size(membership); i++) {
    if (VECTOR(*membership)[i] != MATRIX(*memberships, j, i)) {
      fprintf(f, "WARNING: best membership vector element %li does not match the best one in the membership matrix\n", i);
    }
  }

  fprintf(f, "Modularities:\n");
  igraph_vector_print(modularity);

  for (i=0; i < igraph_matrix_nrow(memberships); i++) {
    for (j=0; j < no_of_nodes; j++) {
      fprintf(f, "%ld ", (long int)MATRIX(*memberships, i, j));
    }
    fprintf(f, "\n");
  }

  fprintf(f, "\n");
}

int main() {
  igraph_t g;
  igraph_vector_t modularity, membership, edges;
  igraph_matrix_t memberships;
  int i, j, k;

  igraph_vector_init(&modularity,0);
  igraph_vector_init(&membership,0);
  igraph_matrix_init(&memberships,0,0);

  /* Unweighted test graph from the paper of Blondel et al */
  igraph_small(&g, 16, IGRAPH_UNDIRECTED,
      0, 2, 0, 3, 0, 4, 0, 5,
      1, 2, 1, 4, 1, 7,
      2, 4, 2, 5, 2, 6,
      3, 7,
      4, 10,
      5, 7, 5, 11,
      6, 7, 6, 11,
      8, 9, 8, 10, 8, 11, 8, 14, 8, 15,
      9, 12, 9, 14,
      10, 11, 10, 12, 10, 13, 10, 14,
      11, 13,
      -1);
  igraph_community_multilevel(&g, 0, &membership, &memberships, &modularity);
  show_results(&g, &membership, &memberships, &modularity, stdout);
  igraph_destroy(&g);

  /* Ring of 30 cliques */
  igraph_vector_init(&edges,0);
  for (i = 0; i < 30; i++) {
    for (j = 0; j < 5; j++) {
      for (k = j+1; k < 5; k++) {
        igraph_vector_push_back(&edges, i*5+j);
        igraph_vector_push_back(&edges, i*5+k);
      }
    }
  }
  for (i = 0; i < 30; i++) {
    igraph_vector_push_back(&edges, i*5 % 150);
    igraph_vector_push_back(&edges, (i*5+6) % 150);
  }
  igraph_create(&g, &edges, 150, 0);
  igraph_community_multilevel(&g, 0, &membership, &memberships, &modularity);
  show_results(&g, &membership, &memberships, &modularity, stdout);
  igraph_destroy(&g);

  igraph_vector_destroy(&modularity);
  igraph_vector_destroy(&membership);
  igraph_vector_destroy(&edges);
  igraph_matrix_destroy(&memberships);

#ifdef __APPLE__
  return 0;
#else
  return 77;
#endif
}