/*
 *
 * gengraph - generation of random simple connected graphs with prescribed
 *            degree sequence
 *
 * Copyright (C) 2006  Fabien Viger
 *
 * 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 <http://www.gnu.org/licenses/>.
 */
#include "gengraph_header.h"
#include "gengraph_graph_molloy_optimized.h"
#include "gengraph_graph_molloy_hash.h"
#include "gengraph_degree_sequence.h"

#include "igraph_datatype.h"
#include "igraph_graphicality.h"
#include "igraph_types.h"
#include "igraph_error.h"

#include "core/exceptions.h"
#include "games/degree_sequence_vl/degree_sequence_vl.h"

namespace gengraph {

// return negative number if program should exit
// int parse_options(int &argc, char** &argv);

// options
// static const bool MONITOR_TIME = false;
static const int  SHUFFLE_TYPE = FINAL_HEURISTICS;
// static const bool RAW_DEGREES  = false;
// static const FILE *Fdeg = stdin;

//_________________________________________________________________________
// int main(int argc, char** argv) {

//   // options
//   SET_VERBOSE(VERBOSE_NONE);
//   if(parse_options(argc, argv) < 0) return -1;

//   //Read degree distribution
//   degree_sequence dd(Fdeg, !RAW_DEGREES);

//   //Allocate memory
//   if(VERBOSE()) fprintf(stderr,"Allocate memory for graph...");
//   graph_molloy_opt g(dd);
//   dd.~degree_sequence();
//   //Realize degree sequence
//   if(VERBOSE()) fprintf(stderr,"done\nRealize degree sequence...");
//   bool FAILED = !g.havelhakimi();
//   if(VERBOSE()) fprintf(stderr," %s\n", FAILED ? "Failed" : "Success");
//   if(FAILED) return 2;
//   //Merge connected components together
//   if(VERBOSE()) fprintf(stderr,"Connecting...");
//   FAILED = !g.make_connected();
//   if(VERBOSE()) fprintf(stderr," %s\n", FAILED ? "Failed" : "Success");
//   if(FAILED) return 3;
//   //Convert graph_molloy_opt to graph_molloy_hash
//   if(VERBOSE()) fprintf(stderr,"Convert adjacency lists into hash tables...");
//   int *hc = g.hard_copy();
//   g.~graph_molloy_opt();
//   graph_molloy_hash gh(hc);
//   delete[] hc;
//   if(VERBOSE()) fprintf(stderr,"Done\n");
//   //Shuffle
//   gh.shuffle(5*gh.nbarcs(), SHUFFLE_TYPE);
//   //Output
//   gh.print();
//   if(MONITOR_TIME) {
//     double t = double(clock()) / double(CLOCKS_PER_SEC);
//     fprintf(stderr,"Time used: %f\n", t);
//   }
//   return 0;
// }

//_________________________________________________________________________
// int parse_options(int &argc, char** &argv) {
// bool HELP = false;
// int argc0 = argc;
// argc = 1;
// for(int a=1; a<argc0; a++) {
//   if(strcmp(argv[a],"-v")==0) SET_VERBOSE(VERBOSE_SOME);
//   else if(strcmp(argv[a],"-vv")==0) SET_VERBOSE(VERBOSE_LOTS);
//   else if(strcmp(argv[a],"-s")==0) my_srandom(0);
//   else if(strcmp(argv[a],"-?")==0 || strcmp(argv[1],"--help")==0 || strcmp(argv[1],"/?")==0) HELP = true;
//   else if(strcmp(argv[a],"-t")==0) MONITOR_TIME = true;
//   else if(strcmp(argv[a],"-g")==0) SHUFFLE_TYPE = GKAN_HEURISTICS;
//   else if(strcmp(argv[a],"-b")==0) SHUFFLE_TYPE = BRUTE_FORCE_HEURISTICS;
//   else if(strcmp(argv[a],"-f")==0) SHUFFLE_TYPE = FAB_HEURISTICS;
//   else if(strcmp(argv[a],"-o")==0) SHUFFLE_TYPE = OPTIMAL_HEURISTICS;
//   else if(strcmp(argv[a],"-raw")==0) RAW_DEGREES=true;
//   else // No option present
//     argv[argc++] = argv[a];
// }
// if(!HELP && argc==2) {
//   Fdeg = fopen(argv[1],"r");
//   if(Fdeg==NULL) {
//     fprintf(stderr,"Error : couldn't open file \"%s\" for reading\n",argv[1]);
//     return -1;
//   }
//   argv[1]=argv[0];
//   argv++;
//   argc--;
// }
// if(HELP || argc!=1) {
//   fprintf(stderr,"Usage : %s [options] [file containing degree distribution]\n",argv[0]);
//   fprintf(stderr," -> %s returns a graph in its standard output\n",argv[0]);
//   fprintf(stderr,"    If no file is given, %s reads its standard input\n",argv[0]);
//   fprintf(stderr,"    [-v] and [-vv] options causes extra verbose.\n");
//   fprintf(stderr,"    [-g] option uses the Gkantsidis heuristics.\n");
//   fprintf(stderr,"    [-b] option uses the Brute Force heuristics.\n");
//   fprintf(stderr,"    [-f] option uses the Modified Gkantsidis heuristics.\n");
//   fprintf(stderr,"    [-o] option uses the Optimal Gkantsidis heuristics.\n");
//   fprintf(stderr,"    [-t] option monitors computation time\n");
//   fprintf(stderr,"    [-s] does a srandom(0) to get a constant random graph\n");
//   fprintf(stderr,"    [-raw] is to take raw degree sequences as input\n");
//   return -1;
// }
//   return 0;
// }


} // namespace gengraph

using namespace gengraph;

igraph_error_t igraph_degree_sequence_game_vl(igraph_t *graph,
                                              const igraph_vector_int_t *out_seq,
                                              const igraph_vector_int_t *in_seq) {
    IGRAPH_HANDLE_EXCEPTIONS(
        igraph_bool_t is_graphical;

        if (in_seq && igraph_vector_int_size(in_seq) != 0) {
            IGRAPH_ERROR("The Viger-Latapy sampler support only undirected graphs.", IGRAPH_EINVAL);
        }

        IGRAPH_CHECK(igraph_is_graphical(out_seq, 0, IGRAPH_SIMPLE_SW, &is_graphical));
        if (!is_graphical) {
            IGRAPH_ERROR("Cannot realize the given degree sequence as an undirected, simple graph.",
                         IGRAPH_EINVAL);
        }

        RNG_BEGIN();

        degree_sequence *dd = new degree_sequence(out_seq);

        graph_molloy_opt *g = new graph_molloy_opt(*dd);
        delete dd;

        if (!g->havelhakimi()) {
            delete g;
            RNG_END();
            IGRAPH_FATAL("g->havelhakimi() failed; please report as a bug.");
        }

        if (!g->make_connected()) {
            delete g;
            RNG_END();
            IGRAPH_ERROR("Cannot make a connected graph from the given degree sequence.",
                         IGRAPH_EINVAL);
        }

        igraph_integer_t *hc = g->hard_copy();
        delete g;
        graph_molloy_hash *gh = new graph_molloy_hash(hc);
        delete [] hc;

        gh->shuffle(5 * gh->nbarcs(), 100 * gh->nbarcs(), SHUFFLE_TYPE);

        IGRAPH_CHECK(gh->print(graph));
        delete gh;

        RNG_END();
    );

    return IGRAPH_SUCCESS;
}
