/******************************************************************************
 * Top contributors (to current version):
 *   Kshitij Bansal, Andrew Reynolds, Morgan Deters
 *
 * This file is part of the cvc5 project.
 *
 * Copyright (c) 2009-2021 by the authors listed in the file AUTHORS
 * in the top-level source directory and their institutional affiliations.
 * All rights reserved.  See the file COPYING in the top-level source
 * directory for licensing information.
 * ****************************************************************************
 *
 * An additional layer between commands and invoking them.
 */

#include "main/command_executor.h"

#ifndef __WIN32__
#  include <sys/resource.h>
#endif /* ! __WIN32__ */

#include <iomanip>
#include <iostream>
#include <memory>
#include <string>
#include <vector>

#include "main/main.h"
#include "options/options_public.h"
#include "smt/command.h"
#include "smt/smt_engine.h"

namespace cvc5 {
namespace main {

// Function to cancel any (externally-imposed) limit on CPU time.
// This is used for competitions while a solution (proof or model)
// is being dumped (so that we don't give "sat" or "unsat" then get
// interrupted partway through outputting a proof!).
void setNoLimitCPU() {
  // Windows doesn't have these things, just ignore
#ifndef __WIN32__
  struct rlimit rlc;
  int st = getrlimit(RLIMIT_CPU, &rlc);
  if(st == 0) {
    rlc.rlim_cur = rlc.rlim_max;
    setrlimit(RLIMIT_CPU, &rlc);
  }
#endif /* ! __WIN32__ */
}

CommandExecutor::CommandExecutor(Options& options)
    : d_solver(new api::Solver(&options)),
      d_symman(new SymbolManager(d_solver.get())),
      d_options(options),
      d_result()
{
}
CommandExecutor::~CommandExecutor()
{
  // ensure that symbol manager is destroyed before solver
  d_symman.reset(nullptr);
  d_solver.reset(nullptr);
}

void CommandExecutor::printStatistics(std::ostream& out) const
{
  if (options::getStatistics(d_options))
  {
    getSmtEngine()->printStatistics(out);
  }
}

void CommandExecutor::printStatisticsSafe(int fd) const
{
  if (options::getStatistics(d_options))
  {
    getSmtEngine()->printStatisticsSafe(fd);
  }
}

bool CommandExecutor::doCommand(Command* cmd)
{
  if (options::getParseOnly(d_options))
  {
    return true;
  }

  CommandSequence *seq = dynamic_cast<CommandSequence*>(cmd);
  if(seq != nullptr) {
    // assume no error
    bool status = true;

    for (CommandSequence::iterator subcmd = seq->begin();
         status && subcmd != seq->end();
         ++subcmd)
    {
      status = doCommand(*subcmd);
    }

    return status;
  } else {
    if (options::getVerbosity(d_options) > 2)
    {
      *options::getOut(d_options) << "Invoking: " << *cmd << std::endl;
    }

    return doCommandSingleton(cmd);
  }
}

void CommandExecutor::reset()
{
  printStatistics(*options::getErr(d_options));
  /* We have to keep options passed via CL on reset. These options are stored
   * in CommandExecutor::d_options (populated and created in the driver), and
   * CommandExecutor::d_options only contains *these* options since the
   * NodeManager copies the options into a new options object before SmtEngine
   * configures additional options based on the given CL options.
   * We can thus safely reuse CommandExecutor::d_options here. */
  d_solver.reset(new api::Solver(&d_options));
}

bool CommandExecutor::doCommandSingleton(Command* cmd)
{
  bool status = true;
  if (options::getVerbosity(d_options) >= -1)
  {
    status = solverInvoke(
        d_solver.get(), d_symman.get(), cmd, options::getOut(d_options));
  }
  else
  {
    status = solverInvoke(d_solver.get(), d_symman.get(), cmd, nullptr);
  }

  api::Result res;
  const CheckSatCommand* cs = dynamic_cast<const CheckSatCommand*>(cmd);
  if(cs != nullptr) {
    d_result = res = cs->getResult();
  }
  const CheckSatAssumingCommand* csa =
      dynamic_cast<const CheckSatAssumingCommand*>(cmd);
  if (csa != nullptr)
  {
    d_result = res = csa->getResult();
  }
  const QueryCommand* q = dynamic_cast<const QueryCommand*>(cmd);
  if(q != nullptr) {
    d_result = res = q->getResult();
  }

  if ((cs != nullptr || q != nullptr) && options::getStatsEveryQuery(d_options))
  {
    getSmtEngine()->printStatisticsDiff(*options::getErr(d_options));
  }

  bool isResultUnsat = res.isUnsat() || res.isEntailed();

  // dump the model/proof/unsat core if option is set
  if (status) {
    std::vector<std::unique_ptr<Command> > getterCommands;
    if (options::getDumpModels(d_options)
        && (res.isSat()
            || (res.isSatUnknown()
                && res.getUnknownExplanation() == api::Result::INCOMPLETE)))
    {
      getterCommands.emplace_back(new GetModelCommand());
    }
    if (options::getDumpProofs(d_options) && isResultUnsat)
    {
      getterCommands.emplace_back(new GetProofCommand());
    }

    if (options::getDumpInstantiations(d_options)
        && ((options::getInstFormatMode(d_options)
                 != options::InstFormatMode::SZS
             && (res.isSat()
                 || (res.isSatUnknown()
                     && res.getUnknownExplanation()
                            == api::Result::INCOMPLETE)))
            || isResultUnsat))
    {
      getterCommands.emplace_back(new GetInstantiationsCommand());
    }

    if (options::getDumpUnsatCores(d_options) && isResultUnsat)
    {
      getterCommands.emplace_back(new GetUnsatCoreCommand());
    }

    if (!getterCommands.empty()) {
      // set no time limit during dumping if applicable
      if (options::getForceNoLimitCpuWhileDump(d_options))
      {
        setNoLimitCPU();
      }
      for (const auto& getterCommand : getterCommands) {
        status = doCommandSingleton(getterCommand.get());
        if (!status)
        {
          break;
        }
      }
    }
  }
  return status;
}

bool solverInvoke(api::Solver* solver,
                  SymbolManager* sm,
                  Command* cmd,
                  std::ostream* out)
{
  if (out == NULL)
  {
    cmd->invoke(solver, sm);
  }
  else
  {
    cmd->invoke(solver, sm, *out);
  }
  // ignore the error if the command-verbosity is 0 for this command
  std::string commandName =
      std::string("command-verbosity:") + cmd->getCommandName();
  if (solver->getOption(commandName) == "0")
  {
    return true;
  }
  return !cmd->fail();
}

void CommandExecutor::flushOutputStreams() {
  printStatistics(*(options::getErr(d_options)));

  // make sure out and err streams are flushed too

  if (options::getOut(d_options) != nullptr)
  {
    *options::getOut(d_options) << std::flush;
  }
  if (options::getErr(d_options) != nullptr)
  {
    *options::getErr(d_options) << std::flush;
  }
}

}  // namespace main
}  // namespace cvc5