/* -*- mode: C -*-  */
/* vim:set ts=4 sw=4 sts=4 et: */
/*
   IGraph library.
   Copyright (C) 2007-2012  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>

#include "test_utilities.h"

int main(void) {
    igraph_t g;
    igraph_vector_int_t membership;
    igraph_vector_t weights;
    igraph_vector_int_t initial;
    igraph_vector_bool_t fixed;
    igraph_integer_t i, j;

    /* Simple triangle graph, the output should be always one community */
    igraph_small(&g, 0, IGRAPH_UNDIRECTED, 0,  1,  0,  2,  1,  2, -1);
    igraph_vector_int_init(&membership, 0);

    for (j = 0; j < 100; j++) {
        /* label propagation is a stochastic method */
        igraph_rng_seed(igraph_rng_default(), j);

        igraph_community_label_propagation(&g, &membership, IGRAPH_ALL, 0, 0, 0);

        for (i = 0; i < 3; i++)
            IGRAPH_ASSERT(VECTOR(membership)[i] == VECTOR(membership)[0]);
    }

    igraph_destroy(&g);

    /* label propagation is a stochastic method */
    igraph_rng_seed(igraph_rng_default(), 765);

    /* Zachary Karate club -- this is just a quick smoke test */
    igraph_small(&g, 0, IGRAPH_UNDIRECTED,
                 0,  1,  0,  2,  0,  3,  0,  4,  0,  5,
                 0,  6,  0,  7,  0,  8,  0, 10,  0, 11,
                 0, 12,  0, 13,  0, 17,  0, 19,  0, 21,
                 0, 31,  1,  2,  1,  3,  1,  7,  1, 13,
                 1, 17,  1, 19,  1, 21,  1, 30,  2,  3,
                 2,  7,  2,  8,  2,  9,  2, 13,  2, 27,
                 2, 28,  2, 32,  3,  7,  3, 12,  3, 13,
                 4,  6,  4, 10,  5,  6,  5, 10,  5, 16,
                 6, 16,  8, 30,  8, 32,  8, 33,  9, 33,
                 13, 33, 14, 32, 14, 33, 15, 32, 15, 33,
                 18, 32, 18, 33, 19, 33, 20, 32, 20, 33,
                 22, 32, 22, 33, 23, 25, 23, 27, 23, 29,
                 23, 32, 23, 33, 24, 25, 24, 27, 24, 31,
                 25, 31, 26, 29, 26, 33, 27, 33, 28, 31,
                 28, 33, 29, 32, 29, 33, 30, 32, 30, 33,
                 31, 32, 31, 33, 32, 33,
                 -1);

    igraph_community_label_propagation(&g, &membership, IGRAPH_ALL, 0, 0, 0);

    igraph_destroy(&g);

    /* Simple star graph to test weights */
    igraph_small(&g, 0, IGRAPH_UNDIRECTED,
                 0,  1,  0,  2,  0,  3,  0,  4,  0,  5,
                 2,  3,  2,  4,  3,  4,  3,  5,  4,  5,  -1);
    igraph_vector_init_int_end(&weights, -1, 5, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1);
    igraph_vector_int_init_int_end(&initial, -1, 0, 0, 1, 1, 1, 1, -1);
    igraph_vector_bool_init(&fixed, 6);
    VECTOR(fixed)[3] = 1;
    VECTOR(fixed)[4] = 1;
    VECTOR(fixed)[5] = 1;
    igraph_community_label_propagation(&g, &membership, IGRAPH_ALL, &weights,
                                       &initial, &fixed);
    for (i = 0; i < igraph_vcount(&g); i++)
        IGRAPH_ASSERT(VECTOR(membership)[i] == (i < 2 ? 0 : 1));

    igraph_community_label_propagation(&g, &membership, IGRAPH_ALL, 0,
                                       &initial, &fixed);
    for (i = 0; i < igraph_vcount(&g); i++)
        IGRAPH_ASSERT(VECTOR(membership)[i] == 0);

    /* Check whether it works with no fixed vertices at all
     * while an initial configuration is given -- see bug
     * #570902 in Launchpad. This is a simple smoke test only. */
    igraph_community_label_propagation(&g, &membership, IGRAPH_ALL, &weights,
                                       &initial, 0);

    igraph_vector_bool_destroy(&fixed);
    igraph_vector_destroy(&weights);
    igraph_vector_int_destroy(&initial);
    igraph_destroy(&g);

    igraph_vector_int_destroy(&membership);

    VERIFY_FINALLY_STACK();

    return 0;
}
