/*
 * Copyright (c) 2014, Sandia Corporation.
 * Under the terms of Contract DE-AC04-94AL85000 with Sandia Corporation,
 * the U.S. Government retains certain rights in this software.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *
 *     * Redistributions in binary form must reproduce the above
 *       copyright notice, this list of conditions and the following
 *       disclaimer in the documentation and/or other materials provided
 *       with the distribution.
 *
 *     * Neither the name of Sandia Corporation nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include "defs.h"    // for FALSE, TRUE
#include "structs.h" // for vtx_data
#include <stdio.h>   // for fprintf, NULL, fclose, etc

/* Print out subgraph in program-readable form. */
void graph_out(struct vtx_data **graph,       /* graph data structure */
               int               nvtxs,       /* number of vtxs in graph */
               int               using_ewgts, /* Are edges weighted? */
               char *            tag,         /* message to include */
               char *            file_name    /* output file name if not null */
               )
{
  FILE *file;        /* output file */
  int   using_vwgts; /* Are vertices weighted? */
  int   nedges;      /* number of edges in graph */
  int   option;      /* output option */
  int   i, j;        /* loop counter */

  if (file_name != NULL)
    file = fopen(file_name, "w");
  else
    file = stdout;

  /* Determine all the appropriate parameters. */
  using_vwgts = FALSE;
  nedges      = 0;
  for (i = 1; i <= nvtxs; i++) {
    if (graph[i]->vwgt != 1)
      using_vwgts = TRUE;
    nedges += graph[i]->nedges - 1;
  }

  option = 0;
  if (using_ewgts)
    option += 1;
  if (using_vwgts)
    option += 10;

  if (tag != NULL)
    fprintf(file, "%% graph_out: %s\n", tag);
  fprintf(file, " %d %d", nvtxs, nedges / 2);
  if (option != 0)
    fprintf(file, "  %d", option);
  fprintf(file, "\n");
  for (i = 1; i <= nvtxs; i++) {
    if (using_vwgts)
      fprintf(file, "%d ", graph[i]->vwgt);
    for (j = 1; j < graph[i]->nedges; j++) {
      fprintf(file, " %d", graph[i]->edges[j]);
      if (using_ewgts)
        fprintf(file, " %.9f ", graph[i]->ewgts[j]);
    }
    fprintf(file, "\n");
  }

  if (file_name != NULL)
    fclose(file);
}
