/* -*- C++ -*-

  *

  * src/lemon/error.h - Part of LEMON, a generic C++ optimization library

  *

  * Copyright (C) 2005 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 Exception safe wrapper class.

   ///

   /// Exception safe wrapper class to implement the members of exceptions.

   template <typename _Type>

   class ExceptionMember {

   public:

     typedef _Type Type;

     ExceptionMember() throw () {

       try {

 	ptr.reset(new Type());

       } catch (...) {}

     }

     ExceptionMember(const Type& type) throw () {

       try {

 	ptr.reset(new Type());

 	if (ptr.get() == 0) return;

 	*ptr = type;

       } catch (...) {}

     }

     ExceptionMember(const ExceptionMember& copy) throw() {

       try {

 	if (!copy.valid()) return;

 	ptr.reset(new Type());

 	if (ptr.get() == 0) return;

 	*ptr = copy.get();

       } catch (...) {}

     }

     ExceptionMember& operator=(const ExceptionMember& copy) {

       if (ptr.get() == 0) return;

       try {

 	if (!copy.valid()) return;

  	*ptr = copy.get();

       } catch (...) {}

     }

     void set(const Type& type) {

       if (ptr.get() == 0) return;

       try {

 	*ptr = type;

       } catch (...) {}

     }

     const Type& get() const {

       return *ptr;

     }

     bool valid() const {

       return ptr.get() != 0;

     }

   private:

     std::auto_ptr<_Type> ptr;

   };

   /// Exception-safe convenient "error message" class.

   /// Helper class which provides a convenient ostream-like (operator <<

   /// based) interface to create a string message. Mostly useful in

   /// exception classes (therefore the name).

   class ErrorMessage {

   protected:

     ///\e 

     ///\todo The good solution is boost:shared_ptr...

     mutable

     std::auto_ptr<std::ostringstream> buf;

     ///\e 

     bool init() throw() {

       try {

 	buf.reset(new std::ostringstream);

       }

       catch(...) {

 	buf.reset();

       }

       return buf.get();

     }

   public:

     ///\e 

     ErrorMessage() throw() { init(); }

     ErrorMessage(const ErrorMessage& em) throw() : buf(em.buf) { }

     ///\e 

     ErrorMessage(const char *message) throw() {

       init();

       *this << message;

     }

     ///\e 

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

       init();

       *this << message;

     }

     ///\e 

     template <typename T>

     ErrorMessage& operator<<(const T &t) throw() {

       if( ! buf.get() ) return *this;

       try {

 	*buf << t;

       }

       catch(...) {

 	buf.reset();

       }

       return *this;

     }

     ///\e 

     const char* message() throw() {

       if( ! buf.get() ) return 0;

       const char* mes = 0;

       try {

 	mes = buf->str().c_str();

       }

       catch(...) {}

       return mes;

     }

   };

   /**

    * \brief Generic exception class.

    *

    * Base class for exceptions used in LEMON.

    */

   class Exception : public std::exception {

   public:

     ///\e 

     Exception() {}

     ///\e 

     virtual ~Exception() throw() {}

     ///\e

     virtual const char* exceptionName() const {

       return "lemon::Exception";

     }

     ///\e 

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

       return exceptionName();

     }

   };

   /**

    * \brief One of the two main subclasses of \ref Exception.

    *

    * Logic errors represent problems in the internal logic of a program;

    * in theory, these are preventable, and even detectable before the

    * program runs (e.g., violations of class invariants).

    *

    * A typical example for this is \ref UninitializedParameter.

    */

   class LogicError : public Exception {

   public:

     virtual const char* exceptionName() const {

       return "lemon::LogicError";

     }

   };

   /**

    * \brief \ref Exception for uninitialized parameters.

    *

    * This error represents problems in the initialization

    * of the parameters of the algorithms.

    */

   class UninitializedParameter : public LogicError {

   public:

     virtual const char* exceptionName() const {

       return "lemon::UninitializedParameter";

     }

   };

   /**

    * \brief One of the two main subclasses of \ref Exception.

    *

    * Runtime errors represent problems outside the scope of a program;

    * they cannot be easily predicted and can generally only be caught as

    * the program executes.

    */

   class RuntimeError : public Exception {

   public:

     virtual const char* exceptionName() const {

       return "lemon::RuntimeError";

     }

   };

   ///\e

   class RangeError : public RuntimeError {

   public:

     virtual const char* exceptionName() const {

       return "lemon::RangeError";

     }

   };

   ///\e 

   class IOError : public RuntimeError {

   public:

     virtual const char* exceptionName() const {

       return "lemon::IOError";

     }

   };

   ///\e 

   class DataFormatError : public IOError {

   protected:

     ExceptionMember<std::string> _message;

     ExceptionMember<std::string> _file;

     int _line;

     mutable ExceptionMember<std::string> _message_holder;

   public:

     DataFormatError(const DataFormatError &dfe) : 

       IOError(dfe), _message(dfe._message), _file(dfe._file),

       _line(dfe._line) {}

     ///\e 

     explicit DataFormatError(const char *the_message)

       : _message(the_message), _line(0) {}

     ///\e 

     DataFormatError(const std::string &file_name, int line_num,

 		    const char *the_message)

       : _message(the_message), _line(line_num) { file(file_name); }

     ///\e 

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

     ///\e 

     void message(const std::string& message) { _message.set(message); }

     ///\e 

     void file(const std::string &file) { _file.set(file); }

     ///\e

     int line() const { return _line; }

     ///\e

     const char* message() const { 

       if (_message.valid() && !_message.get().empty()) {

 	return _message.get().c_str();

       } else {

 	return 0;

       }

     }

     /// \brief Returns the filename.

     ///

     /// Returns \e null if the filename was not specified.

     const char* file() const {

       if (_file.valid() && !_file.get().empty()) {

 	return _file.get().c_str();

       } else {

 	return 0;

       }

     }

     ///\e 

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

       try {

 	std::ostringstream ostr;

 	if (message()) ostr << message();

 	if( file() || line() != 0 ) {

 	  ostr << " (";

 	  if( file() ) ostr << "in file '" << file() << "'";

 	  if( file() && line() != 0 ) ostr << " ";

 	  if( line() != 0 ) ostr << "at line " << line();

 	  ostr << ")";

 	}

 	_message_holder.set(ostr.str());

       }

       catch (...) {}

       if( _message_holder.valid()) return _message_holder.get().c_str();

       return exceptionName();

     }

     virtual const char* exceptionName() const {

       return "lemon::DataFormatError";

     }

     virtual ~DataFormatError() throw() {}

   };

   class IOParameterError : public LogicError {

   protected:

     ExceptionMember<std::string> _message;

     ExceptionMember<std::string> _file;

     mutable ExceptionMember<std::string> _message_holder;

   public:

     IOParameterError(const IOParameterError &ile) : 

       LogicError(ile), _message(ile._message), _file(ile._file) {}

     ///\e 

     explicit IOParameterError(const char *the_message)

       : _message(the_message) {}

     ///\e 

     IOParameterError(const char *file_name, const char *the_message)

       : _message(file_name), _file(file_name) {}

      ///\e 

     void message(const std::string& message) { _message.set(message); }

     ///\e 

     void file(const std::string &file) { _file.set(file); }

      ///\e

     const char* message() const { 

       if (_message.valid()) {

 	return _message.get().c_str();

       } else {

 	return 0;

       }

     }

     /// \brief Returns the filename.

     ///

     /// Returns \e null if the filename was not specified.

     const char* file() const {

       if (_file.valid()) {

 	return _file.get().c_str();

       } else {

 	return 0;

       }

     }

     ///\e 

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

       try {

 	std::ostringstream ostr;

 	if (message()) ostr << message();

 	if (file()) ostr << "(when reading file '" << file() << "')";

 	_message_holder.set(ostr.str());

       }

       catch (...) {}

       if( _message_holder.valid() ) return _message_holder.get().c_str();

       return exceptionName();

     }

     virtual const char* exceptionName() const {

       return "lemon::IOParameterError";

     }

     virtual ~IOParameterError() throw() {}

   };

   ///\e

   class AssertionFailedError : public LogicError {

   protected:

     const char *assertion;

     const char *file;

     int line;

     const char *function;

     const char *message;

     mutable ExceptionMember<std::string> _message_holder;

   public:

     ///\e

     AssertionFailedError(const char *_file, int _line, const char *func,

 			 const char *msg, const char *_assertion = 0) :

       assertion(_assertion), file(_file), line(_line), function(func),

       message(msg) {}

     ///\e

     const char* get_assertion() const { return assertion; }

     ///\e

     const char* get_message() const { return message; }

     ///\e

     const char* get_file() const { return file; }

     ///\e

     const char* get_function() const { return function; }

     ///\e

     int get_line() const { return line; }

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

       try {

 	std::ostringstream ostr;

 	ostr << file << ":" << line << ": ";

 	if( function )

 	  ostr << function << ": ";

 	ostr << message;

 	if( assertion )

 	   ostr << " (assertion '" << assertion << "' failed)";

 	_message_holder.set(ostr.str());

 	return ostr.str().c_str();

       }

       catch(...) {}

       if( _message_holder.valid() ) return _message_holder.get().c_str();

       return exceptionName();

     }

     virtual const char* exceptionName() const {

       return "lemon::AssertionFailedError";

     }

     virtual ~AssertionFailedError() throw() {}

   };

   /****************  Macros  ****************/

   inline

   void assert_fail(const char *file, int line, const char *func,

 		   const char *message, const char *assertion = 0,

 		   bool do_abort=true)

   {

     using namespace std;

     cerr << file << ":" << line << ": ";

     if( func )

       cerr << func << ": ";

     cerr << message;

     if( assertion )

       cerr << " (assertion '" << assertion << "' failed)";

     cerr << endl;

     if(do_abort)

       abort();

   }

   inline

   void assert_fail_throw(const char *file, int line, const char *func,

 		   const char *message, const char *assertion = 0,

 		   bool = true)

   {

     throw AssertionFailedError(file, line, func, message, assertion);

   }

 /// @}

 }

 #endif // LEMON_ERROR_H

 #undef LEMON_ASSERT

 #undef LEMON_FIXME

 #ifndef LEMON_ASSERT_ABORT

 #  define LEMON_ASSERT_ABORT 1

 #endif

 #ifndef LEMON_ASSERT_HANDLER

 #  ifdef LEMON_ASSERT_EXCEPTION

 #    define LEMON_ASSERT_HANDLER ::lemon::assert_fail_throw

 #  else

 #    define LEMON_ASSERT_HANDLER ::lemon::assert_fail

 #  endif

 #endif

 #if defined(NDEBUG) || defined(LEMON_DISABLE_ASSERTS)

 #  define LEMON_ASSERT(exp, msg)  (static_cast<void> (0))

 #else

 /**

  * \brief Macro for assertions with customizable message

  *

  * Macro for assertions with customizable message.

  *

  * The behaviour can be customized with LEMON_ASSERT_HANDLER,

  * LEMON_ASSERT_EXCEPTION and LEMON_ASSERT_ABORT defines. Asserts can be

  * disabled by defining either NDEBUG or LEMON_DISABLE_ASSERTS macros.

  *

  * \todo We should provide some way to reset to the default behaviour,

  * shouldn't we?

  *

  * \todo This whole 'assert' business should be placed in a separate

  * include file.

  *

  * \todo __PRETTY_FUNCTION__ should be replaced by something

  * compiler-independent, like BOOST_CURRENT_FUNCTION

  */

 #  define LEMON_ASSERT(exp, msg)                 \

      (static_cast<void> (!!(exp) ? 0 : (         \

        LEMON_ASSERT_HANDLER(__FILE__, __LINE__,  \

                             __PRETTY_FUNCTION__, \

 			    (msg), #exp, LEMON_ASSERT_ABORT), 0)))

 #endif // NDEBUG || LEMON_DISABLE_ASSERTS

 /**

  * \brief Macro for mark not yet implemented features.

  *

  * \todo Is this the right place for this? It should be used only in

  * modules under development.

  *

  * \todo __PRETTY_FUNCTION__ should be replaced by something

  * compiler-independent, like BOOST_CURRENT_FUNCTION

  */

 # define LEMON_FIXME(msg) \

     (LEMON_ASSERT_HANDLER(__FILE__, __LINE__, __PRETTY_FUNCTION__, \

 			  "FIXME: " msg))