// -*- coding: utf-8 -*-
// Copyright (C) by the Spot authors, see the AUTHORS file for details.
//
// This file is part of Spot, a model checking library.
//
// Spot 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 3 of the License, or
// (at your option) any later version.
//
// Spot 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 "common_sys.hh"

#include <iostream>
#include <argp.h>
#include <cstdlib>
#include "error.h"

#include "common_setup.hh"
#include "common_output.hh"
#include "common_range.hh"
#include "common_r.hh"
#include "common_conv.hh"
#include "common_cout.hh"

#include <spot/tl/defaultenv.hh>
#include <spot/tl/randomltl.hh>
#include <spot/misc/random.hh>
#include <spot/misc/optionmap.hh>

static const char argp_program_doc[] = "\
Generate random temporal logic formulas.\n\n\
The formulas are built over the atomic propositions named by PROPS...\n\
or, if N is a nonnegative number, using N arbitrary names.\v\
Examples:\n\
\n\
The following generates 10 random LTL formulas over the propositions a, b,\n\
and c, with the default tree-size, and all available operators.\n\
  % randltl -n10 a b c\n\
\n\
If you do not mind about the name of the atomic propositions, just give\n\
a number instead:\n\
  % randltl -n10 3\n\
\n\
You can disable or favor certain operators by changing their priority.\n\
The following disables xor, implies, and equiv, and multiply the probability\n\
of X to occur by 10.\n\
  % randltl --ltl-priorities='xor=0, implies=0, equiv=0, X=10' -n10 a b c\n\
";

enum {
  OPT_BOOLEAN_PRIORITIES = 1,
  OPT_DUMP_PRIORITIES,
  OPT_DUPS,
  OPT_LTL_PRIORITIES,
  OPT_SEED,
  OPT_SERE_PRIORITIES,
  OPT_TREE_SIZE,
  OPT_WF,
};

static const argp_option options[] =
  {
    // Keep this alphabetically sorted (expect for aliases).
    /**************************************************/
    { nullptr, 0, nullptr, 0, "Type of formula to generate:", 1 },
    { "boolean", 'B', nullptr, 0, "generate Boolean formulas", 0 },
    { "ltl", 'L', nullptr, 0, "generate LTL formulas (default)", 0 },
    { "sere", 'S', nullptr, 0, "generate SERE", 0 },
    { "psl", 'P', nullptr, 0, "generate PSL formulas", 0 },
    /**************************************************/
    { nullptr, 0, nullptr, 0, "Generation:", 2 },
    { "weak-fairness", OPT_WF, nullptr, 0,
      "append some weak-fairness conditions", 0 },
    { "formulas", 'n', "INT", 0, "number of formulas to output (1)\n"\
      "use a negative value for unbounded generation", 0 },
    { "seed", OPT_SEED, "INT", 0,
      "seed for the random number generator (0)", 0 },
    { "tree-size", OPT_TREE_SIZE, "RANGE", 0,
      "tree size of the formulas generated, before mandatory "\
      "trivial simplifications (15)", 0 },
    { "allow-dups", OPT_DUPS, nullptr, 0,
      "allow duplicate formulas to be output", 0 },
    DECLARE_OPT_R,
    RANGE_DOC,
    LEVEL_DOC(3),
    /**************************************************/
    { nullptr, 0, nullptr, 0, "Adjusting probabilities:", 4 },
    { "dump-priorities", OPT_DUMP_PRIORITIES, nullptr, 0,
      "show current priorities, do not generate any formula", 0 },
    { "ltl-priorities", OPT_LTL_PRIORITIES, "STRING", 0,
      "set priorities for LTL formulas", 0 },
    { "sere-priorities", OPT_SERE_PRIORITIES, "STRING", 0,
      "set priorities for SERE formulas", 0 },
    { "boolean-priorities", OPT_BOOLEAN_PRIORITIES, "STRING", 0,
      "set priorities for Boolean formulas", 0 },
    { nullptr, 0, nullptr, 0, "STRING should be a comma-separated list of "
      "assignments, assigning integer priorities to the tokens "
      "listed by --dump-priorities.", 0 },
    /**************************************************/
    { nullptr, 0, nullptr, 0, "Output options:", -20 },
    { nullptr, 0, nullptr, 0, "The FORMAT string passed to --format may use "
      "the following interpreted sequences:", -19 },
    { "%f", 0, nullptr, OPTION_DOC | OPTION_NO_USAGE,
      "the formula (in the selected syntax)", 0 },
    { "%l", 0, nullptr, OPTION_DOC | OPTION_NO_USAGE,
      "the (serial) number of the formula (0-based)", 0 },
    { "%L", 0, nullptr, OPTION_DOC | OPTION_NO_USAGE,
      "the (serial) number of the formula (1-based)", 0 },
    { "%%", 0, nullptr, OPTION_DOC | OPTION_NO_USAGE,
      "a single %", 0 },
    COMMON_LTL_OUTPUT_SPECS,
    /**************************************************/
    { nullptr, 0, nullptr, 0, "Miscellaneous options:", -1 },
    { nullptr, 0, nullptr, 0, nullptr, 0 }
  };


const struct argp_child children[] =
  {
    { &output_argp, 0, nullptr, 0 },
    { &misc_argp, 0, nullptr, 0 },
    { nullptr, 0, nullptr, 0 }
  };

// We want all these variables to be destroyed when we exit main, to
// make sure it happens before all other global variables (like the
// atomic propositions maps) are destroyed.  Otherwise we risk
// accessing deleted stuff.
static struct opt_t
{
  spot::atomic_prop_set aprops;
}* opt;

static spot::randltlgenerator::output_type output =
  spot::randltlgenerator::LTL;
static char* opt_pL = nullptr;
static char* opt_pS = nullptr;
static char* opt_pB = nullptr;
static bool opt_dump_priorities = false;
static int opt_formulas = 1;
static int opt_seed = 0;
static range opt_tree_size = { 15, 15 };
static bool opt_unique = true;
static bool opt_wf = false;
static bool ap_count_given = false;

static int
parse_opt(int key, char* arg, struct argp_state* as)
{
  // Called from C code, so should not raise any exception.
  BEGIN_EXCEPTION_PROTECT;
  // This switch is alphabetically-ordered.
  switch (key)
    {
    case 'B':
      output = spot::randltlgenerator::Bool;
      break;
    case 'L':
      output = spot::randltlgenerator::LTL;
      break;
    case 'n':
      opt_formulas = to_int(arg, "-n/--formulas");
      break;
    case 'P':
      output = spot::randltlgenerator::PSL;
      break;
    case OPT_R:
      parse_r(arg);
      break;
    case 'S':
      output = spot::randltlgenerator::SERE;
      output_ratexp = true;
      break;
    case OPT_BOOLEAN_PRIORITIES:
      opt_pB = arg;
      break;
    case OPT_DUPS:
      opt_unique = false;
      break;
    case OPT_LTL_PRIORITIES:
      opt_pL = arg;
      break;
    case OPT_DUMP_PRIORITIES:
      opt_dump_priorities = true;
      break;
    case OPT_SERE_PRIORITIES:
      opt_pS = arg;
      break;
    case OPT_SEED:
      opt_seed = to_int(arg, "--seed");
      break;
    case OPT_TREE_SIZE:
      opt_tree_size = parse_range(arg);
      if (opt_tree_size.min > opt_tree_size.max)
        std::swap(opt_tree_size.min, opt_tree_size.max);
      break;
    case OPT_WF:
      opt_wf = true;
      break;
    case ARGP_KEY_ARG:
      // If this is the unique non-option argument, it can
      // be a number of atomic propositions to build.
      //
      // argp reorganizes argv[] so that options always come before
      // non-options.  So if as->argc == as->next we know this is the
      // last non-option argument, and if aprops.empty() we know this
      // is the also the first one.
      if (opt->aprops.empty() && as->argc == as->next)
        {
          char* endptr;
          int res = strtol(arg, &endptr, 10);
          if (!*endptr && res >= 0) // arg is a number
            {
              ap_count_given = true;
              opt->aprops = spot::create_atomic_prop_set(res);
              break;
            }
        }
      opt->aprops.insert(spot::default_environment::instance().require(arg));
      break;
    default:
      return ARGP_ERR_UNKNOWN;
    }
  END_EXCEPTION_PROTECT;
  return 0;
}

int
main(int argc, char** argv)
{
  return protected_main(argv, [&] {
      const argp ap = { options, parse_opt, "N|PROP...", argp_program_doc,
                        children, nullptr, nullptr };

      // This will ensure that all objects stored in this struct are
      // destroyed before global variables.
      opt_t o;
      opt = &o;

      if (int err = argp_parse(&ap, argc, argv, ARGP_NO_HELP, nullptr, nullptr))
        exit(err);

      // running 'randltl 0' is one way to generate formulas using no
      // atomic propositions so do not complain in that case.
      if (opt->aprops.empty() && !ap_count_given)
        error(2, 0, "No atomic proposition supplied?  "
              "Run '%s --help' for usage.", program_name);

      spot::srand(opt_seed);

      spot::randltlgenerator rg
        (opt->aprops,
         [&] (){
          spot::option_map opts;
          opts.set("output", output);
          opts.set("tree_size_min", opt_tree_size.min);
          opts.set("tree_size_max", opt_tree_size.max);
          opts.set("wf", opt_wf);
          opts.set("seed", opt_seed);
          opts.set("simplification_level", simplification_level);
          opts.set("unique", opt_unique);
          return opts;
        }(), opt_pL, opt_pS, opt_pB);

      if (opt_dump_priorities)
        {
          switch (output)
            {
            case spot::randltlgenerator::LTL:
              std::cout <<
                "Use --ltl-priorities to set the following LTL priorities:\n";
              rg.dump_ltl_priorities(std::cout);
              break;
            case spot::randltlgenerator::Bool:
              std::cout <<
                "Use --boolean-priorities to set the following Boolean "
                "formula priorities:\n";
              rg.dump_bool_priorities(std::cout);
              break;
            case spot::randltlgenerator::PSL:
              std::cout <<
                "Use --ltl-priorities to set the following LTL priorities:\n";
              rg.dump_psl_priorities(std::cout);
              SPOT_FALLTHROUGH;
            case spot::randltlgenerator::SERE:
              std::cout <<
                "Use --sere-priorities to set the following SERE priorities:\n";
              rg.dump_sere_priorities(std::cout);
              std::cout <<
                "Use --boolean-priorities to set the following Boolean "
                "formula priorities:\n";
              rg.dump_sere_bool_priorities(std::cout);
              break;
            }
          exit(0);
        }

      int count = 0;
      while (opt_formulas < 0 || opt_formulas--)
        {
          spot::formula f = rg.next();
          if (!f)
            {
              error(2, 0, "failed to generate a new unique formula after %d " \
                    "trials", spot::randltlgenerator::MAX_TRIALS);
            }
          else
            {
              output_formula_checked(f, nullptr, nullptr, count + 1, count);
              ++count;
            }
        };
      flush_cout();
      return 0;
    });
}
