/*********************                                                        */
/*! \file command_executor.h
 ** \verbatim
 ** Top contributors (to current version):
 **   Morgan Deters, Kshitij Bansal, Aina Niemetz
 ** This file is part of the CVC4 project.
 ** Copyright (c) 2009-2019 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.\endverbatim
 **
 ** \brief An additional layer between commands and invoking them.
 **/

#ifndef __CVC4__MAIN__COMMAND_EXECUTOR_H
#define __CVC4__MAIN__COMMAND_EXECUTOR_H

#include <iosfwd>
#include <string>

#include "expr/expr_manager.h"
#include "options/options.h"
#include "smt/command.h"
#include "smt/smt_engine.h"
#include "util/statistics_registry.h"

namespace CVC4 {

namespace api {
class Solver;
}

namespace main {

class CommandExecutor {
private:
  std::string d_lastStatistics;

protected:
 api::Solver* d_solver;
 SmtEngine* d_smtEngine;
 Options& d_options;
 StatisticsRegistry d_stats;
 Result d_result;
 ExprStream* d_replayStream;

public:
 CommandExecutor(api::Solver* solver, Options& options);

 virtual ~CommandExecutor()
 {
   if (d_replayStream != NULL)
   {
     delete d_replayStream;
   }
  }

  /**
   * Executes a command. Recursively handles if cmd is a command
   * sequence.  Eventually uses doCommandSingleton (which can be
   * overridden by a derived class).
   */
  bool doCommand(CVC4::Command* cmd);

  Result getResult() const { return d_result; }
  void reset();

  StatisticsRegistry& getStatisticsRegistry() {
    return d_stats;
  }

  SmtEngine* getSmtEngine() { return d_smtEngine; }

  /**
   * Flushes statistics to a file descriptor.
   */
  virtual void flushStatistics(std::ostream& out) const;

  /**
   * Flushes statistics to a file descriptor.
   * Safe to use in a signal handler.
   */
  void safeFlushStatistics(int fd) const;

  static void printStatsFilterZeros(std::ostream& out,
                                    const std::string& statsString);

  LemmaChannels* channels() { return d_smtEngine->channels(); }
  void flushOutputStreams();

  void setReplayStream(ExprStream* replayStream);

protected:
  /** Executes treating cmd as a singleton */
  virtual bool doCommandSingleton(CVC4::Command* cmd);

private:
  CommandExecutor();

};/* class CommandExecutor */

bool smtEngineInvoke(SmtEngine* smt, Command* cmd, std::ostream *out);

}/* CVC4::main namespace */
}/* CVC4 namespace */

#endif  /* __CVC4__MAIN__COMMAND_EXECUTOR_H */