/* -*- mode: C++; indent-tabs-mode: nil; -*-

 *

 * This file is a part of LEMON, a generic C++ optimization library.

 *

 * Copyright (C) 2003-2008

 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport

 * (Egervary Research Group on Combinatorial Optimization, EGRES).

 *

 * Permission to use, modify and distribute this software is granted

 * provided that this copyright notice appears in all copies. For

 * precise terms see the accompanying LICENSE file.

 *

 * This software is provided "AS IS" with no warranty of any kind,

 * express or implied, and with no claim as to its suitability for any

 * purpose.

 *

 */

#ifndef LEMON_ERROR_H

#define LEMON_ERROR_H

/// \ingroup exceptions

/// \file

/// \brief Basic exception classes and error handling.

#include <exception>

#include <string>

#include <sstream>

#include <iostream>

#include <cstdlib>

#include <memory>

namespace lemon {

  /// \addtogroup exceptions

  /// @{

  /// \brief Generic exception class.

  ///

  /// Base class for exceptions used in LEMON.

  ///

  class Exception : public std::exception {

  public:

    ///Constructor

    Exception() throw() {}

    ///Virtual destructor

    virtual ~Exception() throw() {}

    ///A short description of the exception

    virtual const char* what() const throw() {

      return "lemon::Exception";

    }

  };

  /// \brief Input-Output error

  ///

  /// This exception is thrown when a file operation cannot be

  /// succeeded.

  class IoError : public Exception {

  protected:

    std::string _message;

    std::string _file;

    mutable std::string _what;

  public:

    /// Copy constructor

    IoError(const IoError &error) throw() : Exception() {

      message(error._message);

      file(error._file);

    }

    /// Constructor

    explicit IoError(const char *message) throw() {

      IoError::message(message);

    }

    /// Constructor

    explicit IoError(const std::string &message) throw() {

      IoError::message(message);

    }

    /// Constructor

    explicit IoError(const char *message,

                     const std::string &file) throw() {

      IoError::message(message);

      IoError::file(file);

    }

    /// Constructor

    explicit IoError(const std::string &message,

                     const std::string &file) throw() {

      IoError::message(message);

      IoError::file(file);

    }

    /// Virtual destructor

    virtual ~IoError() throw() {}

    /// Set the error message

    void message(const char *message) throw() {

      try {

        _message = message;

      } catch (...) {}

    }

    /// Set the error message

    void message(const std::string& message) throw() {

      try {

        _message = message;

      } catch (...) {}

    }

    /// Set the file name

    void file(const std::string &file) throw() {

      try {

        _file = file;

      } catch (...) {}

    }

    /// Returns the error message

    const std::string& message() const throw() {

      return _message;

    }

    /// \brief Returns the filename

    ///

    /// Returns the filename or an empty string if it was not specified.

    const std::string& file() const throw() {

      return _file;

    }

    /// \brief Returns a short error message

    ///

    /// Returns a short error message which contains the message and the

    /// file name.

    virtual const char* what() const throw() {

      try {

        _what.clear();

        std::ostringstream oss;

        oss << "lemon:IoError" << ": ";

        oss << _message;

        if (!_file.empty()) {

          oss << " ('" << _file << "')";

        }

        _what = oss.str();

      }

      catch (...) {}

      if (!_what.empty()) return _what.c_str();

      else return "lemon:IoError";

    }

  };

  /// \brief Format error

  ///

  /// This exception is thrown when an input file has wrong

  /// format or a data representation is not legal.

  class FormatError : public Exception {

  protected:

    std::string _message;

    std::string _file;

    int _line;

    mutable std::string _what;

  public:

    /// Copy constructor

    FormatError(const FormatError &error) throw() : Exception() {

      message(error._message);

      file(error._file);

      line(error._line);

    }

    /// Constructor

    explicit FormatError(const char *message) throw() {

      FormatError::message(message);

      _line = 0;

    }

    /// Constructor

    explicit FormatError(const std::string &message) throw() {

      FormatError::message(message);

      _line = 0;

    }

    /// Constructor

    explicit FormatError(const char *message,

                         const std::string &file, int line = 0) throw() {

      FormatError::message(message);

      FormatError::file(file);

      FormatError::line(line);

    }

    /// Constructor

    explicit FormatError(const std::string &message,

                         const std::string &file, int line = 0) throw() {

      FormatError::message(message);

      FormatError::file(file);

      FormatError::line(line);

    }

    /// Virtual destructor

    virtual ~FormatError() throw() {}

    /// Set the line number

    void line(int line) throw() { _line = line; }

    /// Set the error message

    void message(const char *message) throw() {

      try {

        _message = message;

      } catch (...) {}

    }

    /// Set the error message

    void message(const std::string& message) throw() {

      try {

        _message = message;

      } catch (...) {}

    }

    /// Set the file name

    void file(const std::string &file) throw() {

      try {

        _file = file;

      } catch (...) {}

    }

    /// \brief Returns the line number

    ///

    /// Returns the line number or zero if it was not specified.

    int line() const throw() { return _line; }

    /// Returns the error message

    const std::string& message() const throw() {

      return _message;

    }

    /// \brief Returns the filename

    ///

    /// Returns the filename or an empty string if it was not specified.

    const std::string& file() const throw() {

      return _file;

    }

    /// \brief Returns a short error message

    ///

    /// Returns a short error message which contains the message, the

    /// file name and the line number.

    virtual const char* what() const throw() {

      try {

        _what.clear();

        std::ostringstream oss;

        oss << "lemon:FormatError" << ": ";

        oss << _message;

        if (!_file.empty() || _line != 0) {

          oss << " (";

          if (!_file.empty()) oss << "in file '" << _file << "'";

          if (!_file.empty() && _line != 0) oss << " ";

          if (_line != 0) oss << "at line " << _line;

          oss << ")";

        }

        _what = oss.str();

      }

      catch (...) {}

      if (!_what.empty()) return _what.c_str();

      else return "lemon:FormatError";

    }

  };

  /// @}

}

#endif // LEMON_ERROR_H