/*
   igraph library.
   Copyright (C) 2021  The igraph development team <igraph@igraph.org>

   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, see <https://www.gnu.org/licenses/>.
*/

#include <igraph.h>
#include "test_utilities.h"

void call_and_print(igraph_t *graph, igraph_int_t pnode, igraph_neimode_t mode, igraph_loops_t loops) {
    igraph_vector_int_t eids;
    igraph_vector_int_init(&eids, 0);
    IGRAPH_ASSERT(igraph_incident(graph, &eids, pnode, mode, loops) == IGRAPH_SUCCESS);
    print_vector_int(&eids);
    igraph_vector_int_destroy(&eids);
}


int main(void) {
    igraph_t g_1, g_lm, g_lmu, g_s1, g_s2;

    igraph_small(&g_1, 1, 0, -1);
    igraph_small(&g_lm, 6, 1, 0,1, 0,2, 1,1, 1,3, 2,0, 2,0, 2,3, 3,4, 3,4, -1);
    igraph_small(&g_lmu, 6, 0, 0,1, 0,2, 1,1, 1,3, 2,0, 2,0, 2,3, 3,4, 3,4, -1);
    igraph_small(&g_s1, 2, 1, 0,1, 0,1, 1,0, 1,0, -1);
    igraph_small(&g_s2, 2, 1, 0,1, 1,0, 1,0, -1);

    igraph_vector_int_t eids;
    igraph_vector_int_init(&eids, 0);

    printf("One vertex:\n");
    call_and_print(&g_1, 0, IGRAPH_ALL, IGRAPH_LOOPS_ONCE);

    printf("Vertex with multiple edges, IGRAPH_IN:\n");
    call_and_print(&g_lm, 0, IGRAPH_IN, IGRAPH_LOOPS_ONCE);

    printf("Vertex with multiple edges, IGRAPH_OUT:\n");
    call_and_print(&g_lm, 0, IGRAPH_OUT, IGRAPH_LOOPS_ONCE);

    printf("Vertex with multiple edges, IGRAPH_ALL:\n");
    call_and_print(&g_lm, 0, IGRAPH_ALL, IGRAPH_LOOPS_TWICE);

    printf("Vertex with multiple edges, undirected:\n");
    call_and_print(&g_lmu, 0, IGRAPH_IN, IGRAPH_LOOPS_ONCE);

    printf("Vertex 1 with loop, IGRAPH_OUT, IGRAPH_NO_LOOPS:\n");
    call_and_print(&g_lm, 1, IGRAPH_OUT, IGRAPH_NO_LOOPS);

    printf("Vertex 1 with loop, IGRAPH_ALL, IGRAPH_NO_LOOPS:\n");
    call_and_print(&g_lm, 1, IGRAPH_ALL, IGRAPH_NO_LOOPS);

    printf("Vertex 1 with loop, undirected, IGRAPH_NO_LOOPS:\n");
    call_and_print(&g_lmu, 1, IGRAPH_IN, IGRAPH_NO_LOOPS);

    printf("Vertex 1 with loop, IGRAPH_OUT, IGRAPH_LOOPS_ONCE:\n");
    call_and_print(&g_lm, 1, IGRAPH_OUT, IGRAPH_LOOPS_ONCE);

    printf("Vertex 1 with loop, IGRAPH_ALL, IGRAPH_LOOPS_ONCE:\n");
    call_and_print(&g_lm, 1, IGRAPH_ALL, IGRAPH_LOOPS_ONCE);

    printf("Vertex 1 with loop, undirected, IGRAPH_LOOPS_ONCE:\n");
    call_and_print(&g_lmu, 1, IGRAPH_IN, IGRAPH_LOOPS_ONCE);

    printf("Vertex 1 with loop, IGRAPH_OUT, IGRAPH_LOOPS_TWICE:\n");
    call_and_print(&g_lm, 1, IGRAPH_OUT, IGRAPH_LOOPS_TWICE);

    printf("Vertex 1 with loop, IGRAPH_ALL, IGRAPH_LOOPS_TWICE:\n");
    call_and_print(&g_lm, 1, IGRAPH_ALL, IGRAPH_LOOPS_TWICE);

    printf("Vertex 1 with loop, undirected, IGRAPH_LOOPS_TWICE:\n");
    call_and_print(&g_lmu, 1, IGRAPH_IN, IGRAPH_LOOPS_TWICE);

    printf("Graph with 2 edges from 0 to 1, and 2 from 1 to 0, IGRAPH_ALL:\n");
    call_and_print(&g_s1, 0, IGRAPH_ALL, IGRAPH_LOOPS_ONCE);

    printf("Graph with 1 edge from 0 to 1, and 2 from 1 to 0, IGRAPH_ALL:\n");
    call_and_print(&g_s2, 0, IGRAPH_ALL, IGRAPH_LOOPS_ONCE);

    VERIFY_FINALLY_STACK();

    printf("Vertex not in graph:\n");
    CHECK_ERROR(igraph_neighbors(&g_lm, &eids, 100, IGRAPH_OUT, IGRAPH_LOOPS_ONCE, IGRAPH_NO_MULTIPLE), IGRAPH_EINVVID);

    printf("Non-existent mode:\n");
    CHECK_ERROR(igraph_neighbors(&g_lm, &eids, 0, (igraph_neimode_t) 100, IGRAPH_LOOPS_ONCE, IGRAPH_NO_MULTIPLE), IGRAPH_EINVMODE);

    igraph_destroy(&g_1);
    igraph_destroy(&g_lm);
    igraph_destroy(&g_lmu);
    igraph_destroy(&g_s1);
    igraph_destroy(&g_s2);
    igraph_vector_int_destroy(&eids);

    VERIFY_FINALLY_STACK();
    return 0;
}
