/*

  This file is part of solidity.

  solidity 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.

  solidity 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 solidity.  If not, see <http://www.gnu.org/licenses/>.

*/

// SPDX-License-Identifier: GPL-3.0

/**

 * @author Christian <c@ethdev.com>

 * @date 2016

 * Solidity parser shared functionality.

 */

#pragma once

#include <liblangutil/Token.h>

#include <memory>

#include <string>

namespace solidity::langutil

{

class ErrorReporter;

class Scanner;

struct SourceLocation;

struct ErrorId;

class ParserBase

{

public:

  /// Set @a _parserErrorRecovery to true for additional error

  /// recovery.  This is experimental and intended for use

  /// by front-end tools that need partial AST information even

  /// when errors occur.

  explicit ParserBase(ErrorReporter& errorReporter, bool _parserErrorRecovery = false): m_errorReporter(errorReporter)

  {

    m_parserErrorRecovery = _parserErrorRecovery;

  }

  virtual ~ParserBase() = default;

protected:

  /// Utility class that creates an error and throws an exception if the

  /// recursion depth is too deep.

  class RecursionGuard

  {

  public:

    explicit RecursionGuard(ParserBase& _parser): m_parser(_parser)

    {

      m_parser.increaseRecursionDepth();

    }

    ~RecursionGuard() { m_parser.decreaseRecursionDepth(); }

  private:

    ParserBase& m_parser;

  };

  /// Location of the current token

  virtual SourceLocation currentLocation() const;

  ///@{

  ///@name Helper functions

  /// If current token value is not @a _value, throw exception otherwise advance token

  //  @a if _advance is true and error recovery is in effect.

  void expectToken(Token _value, bool _advance = true);

  /// Like expectToken but if there is an error ignores tokens until

  /// the expected token or EOS is seen. If EOS is encountered, back up to the error point,

  /// and throw an exception so that a higher grammar rule has an opportunity to recover.

  void expectTokenOrConsumeUntil(Token _value, std::string const& _currentNodeName, bool _advance = true);

  Token currentToken() const;

  Token peekNextToken() const;

  std::string tokenName(Token _token);

  std::string currentLiteral() const;

  virtual Token advance();

  ///@}

  /// Increases the recursion depth and throws an exception if it is too deep.

  void increaseRecursionDepth();

  void decreaseRecursionDepth();

  /// Creates a @ref ParserError and annotates it with the current position and the

  /// given @a _description.

  void parserError(ErrorId _error, std::string const& _description);

  void parserError(ErrorId _error, SourceLocation const& _location, std::string const& _description);

  /// Creates a @ref ParserWarning and annotates it with the current position and the

  /// given @a _description.

  void parserWarning(ErrorId _error, std::string const& _description);

  void parserWarning(ErrorId _error, SourceLocation const& _location, std::string const& _description);

  /// Creates a @ref ParserError and annotates it with the current position and the

  /// given @a _description. Throws the FatalError.

  void fatalParserError(ErrorId _error, std::string const& _description);

  void fatalParserError(ErrorId _error, SourceLocation const& _location, std::string const& _description);

  std::shared_ptr<Scanner> m_scanner;

  /// The reference to the list of errors, warnings and infos to add errors/warnings/infos during parsing

  ErrorReporter& m_errorReporter;

  /// Current recursion depth during parsing.

  size_t m_recursionDepth = 0;

  /// True if we are in parser error recovery. Usually this means we are scanning for

  /// a synchronization token like ';', or '}'. We use this to reduce cascaded error messages.

  bool m_inParserRecovery = false;

  bool m_parserErrorRecovery = false;

};

}