/*
   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>

int main(void) {

    igraph_t g1, g2, res;
    igraph_vector_int_t v;
    igraph_vector_int_t map1, map2;

    /* Initialize the library. */
    igraph_setup();

    igraph_vector_int_init(&map1, 0);
    igraph_vector_int_init(&map2, 0);

    /* composition with the empty graph */
    igraph_empty(&g1, 5, IGRAPH_DIRECTED);
    igraph_full(&g2, 5, IGRAPH_DIRECTED, IGRAPH_NO_LOOPS);
    igraph_compose(&res, &g1, &g2, &map1, &map2);
    if (igraph_ecount(&res) != 0) {
        return 1;
    }
    if (igraph_vector_int_size(&map1) != 0 || igraph_vector_int_size(&map2) != 0) {
        return 11;
    }
    igraph_destroy(&res);
    igraph_compose(&res, &g2, &g1, &map1, &map2);
    if (igraph_ecount(&res) != 0) {
        return 2;
    }
    if (igraph_vector_int_size(&map1) != 0 || igraph_vector_int_size(&map2) != 0) {
        return 12;
    }
    igraph_destroy(&res);
    igraph_destroy(&g1);
    igraph_destroy(&g2);

    /* same but undirected */
    igraph_empty(&g1, 5, IGRAPH_UNDIRECTED);
    igraph_full(&g2, 5, IGRAPH_UNDIRECTED, IGRAPH_NO_LOOPS);
    igraph_compose(&res, &g1, &g2, &map1, &map2);
    if (igraph_ecount(&res) != 0) {
        return 1;
    }
    if (igraph_vector_int_size(&map1) != 0 || igraph_vector_int_size(&map2) != 0) {
        return 11;
    }
    igraph_destroy(&res);
    igraph_compose(&res, &g2, &g1, &map1, &map2);
    if (igraph_ecount(&res) != 0) {
        return 2;
    }
    if (igraph_vector_int_size(&map1) != 0 || igraph_vector_int_size(&map2) != 0) {
        return 12;
    }
    igraph_destroy(&res);
    igraph_destroy(&g1);
    igraph_destroy(&g2);

    /* proper directed graph */
    igraph_vector_int_init_int_end(&v, -1, 0, 1, 1, 2, 5, 6, -1);
    igraph_create(&g1, &v, 0, IGRAPH_DIRECTED);
    igraph_vector_int_destroy(&v);

    igraph_vector_int_init_int_end(&v, -1, 0, 1, 2, 4, 5, 6, -1);
    igraph_create(&g2, &v, 0, IGRAPH_DIRECTED);
    igraph_vector_int_destroy(&v);

    igraph_compose(&res, &g1, &g2, &map1, &map2);
    igraph_write_graph_edgelist(&res, stdout);
    igraph_vector_int_print(&map1);
    igraph_vector_int_print(&map2);
    igraph_destroy(&res);
    igraph_destroy(&g1);
    igraph_destroy(&g2);

    /* undirected graph */
    igraph_vector_int_init_int_end(&v, -1, 0, 1, 1, 2, 5, 6, -1);
    igraph_create(&g1, &v, 0, IGRAPH_UNDIRECTED);
    igraph_vector_int_destroy(&v);

    igraph_vector_int_init_int_end(&v, -1, 0, 1, 0, 4, 5, 6, -1);
    igraph_create(&g2, &v, 0, IGRAPH_UNDIRECTED);
    igraph_vector_int_destroy(&v);

    igraph_compose(&res, &g1, &g2, &map1, &map2);
    igraph_write_graph_edgelist(&res, stdout);
    igraph_vector_int_print(&map1);
    igraph_vector_int_print(&map2);
    igraph_destroy(&res);
    igraph_destroy(&g1);
    igraph_destroy(&g2);

    igraph_vector_int_destroy(&map2);
    igraph_vector_int_destroy(&map1);

    return 0;
}
