/* **********************************************************************
MiniSat -- Copyright (c) 2005, Niklas Sorensson
http://www.cs.chalmers.se/Cs/Research/FormalMethods/MiniSat/

Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
********************************************************************** */
// Modified to compile with MS Visual Studio 6.0 by Alan Mishchenko

#include "solver.h"

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <limits.h>
#include <signal.h>

#ifdef GMP
#include <gmp.h>
#endif

// ======================================================================
// Helpers:

// Reads an input stream to end-of-file and returns the result as a
// 'char*' terminated by '\0' (dynamic allocation in case 'in' is
// standard input).
char *readFile(FILE *in) {
  char *data = malloc(65536);
  int cap = 65536;
  int size = 0;

  while (!feof(in)) {
    if (size == cap) {
      cap *= 2;
      data = realloc(data, cap);
    }
    size += fread(&data[size], 1, 65536, in);
  }
  data = realloc(data, size + 1);
  data[size] = '\0';

  return data;
}

// static inline double cpuTime(void) {
//   struct rusage ru;
//   getrusage(RUSAGE_SELF, &ru);
//   return (double)ru.ru_utime.tv_sec + (double)ru.ru_utime.tv_usec / 1000000;
// }

// ======================================================================
// DIMACS Parser:

static inline void skipWhitespace(char **in) {
  while ((**in >= 9 && **in <= 13) || **in == 32) {
    (*in)++;
  }
}

static inline void skipLine(char **in) {
  for (;;) {
    if (**in == 0) {
      return;
    }
    if (**in == '\n') {
      (*in)++;
      return;
    }
    (*in)++;
  }
}

static inline int parseInt(char **in) {
  int val = 0;
  int _neg = 0;

  skipWhitespace(in);
  if (**in == '-') {
    _neg = 1;
    (*in)++;
  } else if (**in == '+') {
    (*in)++;
  }
  if (**in < '0' || **in > '9') {
    fprintf(stderr, "PARSE ERROR! Unexpected char: %c\n", **in);
    exit(1);
  }
  while (**in >= '0' && **in <= '9') {
    val = val * 10 + (**in - '0');
    (*in)++;
  }
  return _neg ? -val : val;
}

static void readClause(char **in, solver *s, veci *lits) {
  int parsed_lit, var;

  veci_resize(lits, 0);
  for (;;) {
    parsed_lit = parseInt(in);
    if (parsed_lit == 0) {
      break;
    }
    var = abs(parsed_lit) - 1;
    veci_push(lits, (parsed_lit > 0 ? toLit(var) : lit_neg(toLit(var))));
  }
}

static lbool parse_DIMACS_main(char *in, solver *s) {
  veci lits;
  veci_new(&lits);

  for (;;) {
    skipWhitespace(&in);
    if (*in == 0) {
      break;
    } else if (*in == 'c' || *in == 'p') {
      skipLine(&in);
    } else {
      lit *begin;

      readClause(&in, s, &lits);
      begin = veci_begin(&lits);
      if (!solver_addclause(s, begin, veci_size(&lits))) {
	veci_delete(&lits);
	return l_False;
      }
    }
  }
  veci_delete(&lits);
  return solver_simplify(s);  // note: this casts a bool to lbool,
                              // probably a bug.
}

// Inserts problem into solver. Returns FALSE upon immediate conflict.
static lbool parse_DIMACS(FILE *in, solver *s) {
  char *text = readFile(in);
  lbool ret = parse_DIMACS_main(text, s);

  free(text);
  return ret;
}

// ======================================================================

void printStats(stats *stats, int cpu_time, bool interrupted) {
  double Time = (float)(cpu_time) / (float)(CLOCKS_PER_SEC);

  printf("restarts          : %12llu\n", stats->starts);
  printf("conflicts         : %12.0f           (%9.0f / sec      )\n", (double)stats->conflicts, (double)stats->conflicts / Time);
  printf("decisions         : %12.0f           (%9.0f / sec      )\n", (double)stats->decisions, (double)stats->decisions / Time);
  printf("propagations      : %12.0f           (%9.0f / sec      )\n", (double)stats->propagations, (double)stats->propagations / Time);
  printf("inspects          : %12.0f           (%9.0f / sec      )\n", (double)stats->inspects, (double)stats->inspects / Time);
  printf("conflict literals : %12.0f           (%9.2f %% deleted  )\n", (double)stats->tot_literals, (double)(stats->max_literals - stats->tot_literals)*100.0 / (double)stats->max_literals);
  printf("CPU time          : %12.2f sec\t", Time);
  printf("\n");

#ifdef NONDISJOINT
  printf("disjoint          : disabled\n");
#else
  printf("disjoint          : enabled\n");
#endif

#ifdef FIXEDORDER
  printf("variable ordering : fixed\n");
#else
  printf("variable ordering : heuristic\n");
#endif

#ifdef CONTINUE
  printf("continuation      : enabled\n");
#else
  printf("continuation      : disabled\n");
#endif

#ifdef GMP
  printf("gmp               : enabled\n");
#ifdef SIMPLIFY
  printf("simplification    : enabled\n");
  printf("SAT (partial)     : ");
  mpz_out_str(stdout, 10, stats->par_solutions);
  if (interrupted) {
    printf("+");
  }
  printf("\n");

#ifndef NONDISJOINT
  printf("SAT (full)        : ");
  mpz_out_str(stdout, 10, stats->tot_solutions);
  if (interrupted) {
    printf("+");
  }
  printf("\n");
#endif

#else				/* NO SIMPLIFY */
  printf("simplification    : disabled\n");
  printf("SAT (full)        : ");
  mpz_out_str(stdout, 10, stats->tot_solutions);
  if (interrupted) {
    printf("+");
  }
  printf("\n");
#endif

#else				// if GMP not defined
  printf("gmp               : disabled\n");
#ifdef SIMPLIFY
  printf("simplification    : enabled\n");
  printf("SAT (partial)     : %12llu", stats->par_solutions);	// partial assignments which cover the whole solution space.
  if (stats->par_solutions == ULONG_MAX || interrupted) {
    printf("+");		// overflow or interrupted
  }
  printf("\n");

#ifndef NONDISJOINT
  printf("SAT (full)        : %12llu", stats->tot_solutions);
  if (stats->tot_solutions == ULONG_MAX || interrupted) {
    printf("+");		// overflow or interrupted
  }
  printf("\n");
#endif

#else				/*NO SIMPLIFY */
  printf("simplification    : disabled\n");
  printf("SAT (full)        : %12llu", stats->tot_solutions);
  if (stats->tot_solutions == ULONG_MAX || interrupted) {
    printf("+");		// overflow or interrupted
  }
  printf("\n");
#endif
#endif				// GMP
}

solver *slv;

static void SIGINT_handler(int signum) {
  printf("\n");
  printf("*** INTERRUPTED ***\n");
  printStats(&slv->stats, clock() - slv->stats.clk, true);
  printf("\n");
  printf("*** INTERRUPTED ***\n");
  exit(0);
}

// ======================================================================

static inline void PRINT_USAGE(char *p) {
  fprintf(stderr, "Usage:\t%s [options] input-file [output-file]\n", (p));
}


int main(int argc, char **argv) {
  solver *s = solver_new();
  lbool st;
  FILE *in;
  FILE *out;
  s->stats.clk = clock();

  char *infile = NULL;
  char *outfile = NULL;

  /* Receive inputs */
  for (int i = 1; i < argc; i++) {
    if (argv[i][0] == '-') {
      switch (argv[i][1]) {
      case '?':
      case 'h':
      default:
	PRINT_USAGE(argv[0]);
	return 0;
      }
    } else {
      if (infile == NULL) {
	infile = argv[i];
      } else if (outfile == NULL) {
	outfile = argv[i];
      } else {
	PRINT_USAGE(argv[0]);
	return 0;
      }
    }
  }
  if (infile == NULL) {
    PRINT_USAGE(argv[0]);
    return 0;
  }

  in = fopen(infile, "rb");
  if (in == NULL) {
    fprintf(stderr, "ERROR! Could not open file: %s\n", argc == 1 ? "<stdin>" : infile);
    exit(1);
  }
  if (outfile != NULL) {
    out = fopen(outfile, "wb");
    if (out == NULL) {
      fprintf(stderr, "ERROR! Could not open file: %s\n", argc == 1 ? "<stdin>" : outfile);
      exit(1);
    } else {
      s->out = out;
    }
  } else {
    out = NULL;
  }

  st = parse_DIMACS(in, s);
  fclose(in);

  if (st == l_False) {
    solver_delete(s);
    printf("Trivial problem\nUNSATISFIABLE\n");
    exit(20);
  }
  s->verbosity = 1;
  slv = s;
  if (signal(SIGINT, SIGINT_handler) == SIG_ERR) {
    fprintf(stderr, "ERROR! Cound not set signal");
    exit(1);
  }

  solver_solve(s);

  printf("input             : %s\n", infile);
  printStats(&s->stats, clock() - s->stats.clk, false);

  solver_delete(s);
  return 0;
}