/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */

/*

 * Copyright (c) 2006,2007 INRIA

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation;

 *

 * This program 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 this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 *

 * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>

 */

#ifndef __LOG_H__

#define __LOG_H__

#include <string>

#include <iostream>

/**

 * \defgroup logging Logging

 * \brief Logging functions and macros

 *

 *   LOG functionality: macros which allow developers to

 *     send information out on screen. All logging messages 

 *     are disabled by default. To enable selected logging 

 *     messages, use the ns3::LogComponentEnable

 *     function or use the NS_LOG environment variable and 

 *     ns3::LogComponentEnableEnvVar

 *

 * Use the environment variable NS_LOG to define a ';'-separated list of

 * logging components to enable. For example, NS_LOG=a;b;c;DAFD;GH

 * would enable the components 'a', 'b', 'c', 'DAFD', and, 'GH'.

 * NS_LOG=* will enable all available log components.

 *

 * For each component, the "debug" log level is enabled by default

 * but more components can be enabled selectively with the following

 * syntax: NS_LOG='Component1=func|param|warn;Component2=error|debug'

 * This example would enable the 'func', 'param', and 'warn' log

 * levels for 'Component1' and the 'error' and 'debug' log levels

 * for 'Component2'.  The wildcard can be used here as well.  For example

 * NS_LOG='*=level_all|prefix' would enable all log levels and prefix all

 * prints with the component and function names.

 *

 */

/**

 * \ingroup logging

 * \param name a string

 *

 * Define a Log component with a specific name. This macro

 * should be used at the top of every file in which you want 

 * to use the NS_LOG macro. This macro defines a new

 * "log component" which can be later selectively enabled

 * or disabled with the ns3::LogComponentEnable and 

 * ns3::LogComponentDisable functions or with the NS_LOG

 * environment variable.

 */

#ifdef NS3_LOG_ENABLE

#define NS_LOG_COMPONENT_DEFINE(name)                                \

  static ns3::LogComponent g_log = ns3::LogComponent (name)

#else

#define NS_LOG_COMPONENT_DEFINE(name)

#endif

/**

 * \ingroup logging

 * \param msg message to output

 *

 * Generate logging output in the "log component" of the 

 * current file. i.e., every call to NS_LOG from within

 * a file implicitely generates out within the component

 * defined with the NS_LOG_COMPONENT_DEFINE macro in the

 * same file.

 */

#ifdef NS3_LOG_ENABLE

namespace ns3 {

struct EndParameterListStruct {};

extern EndParameterListStruct EndParameterList;

struct ParameterName

{

  const char *name;

  ParameterName (const char *name_) : name (name_) {}

};

class ParameterLogger : public std::ostream

{

  int m_itemNumber;

  const char *m_parameterName;

public:

  ParameterLogger ()

    : m_itemNumber (0)

  {}

  template<typename T>

  ParameterLogger& operator<< (T param)

  {

    switch (m_itemNumber)

      {

      case 0: // first item is actually the function name

        if (m_parameterName)

          {

            std::clog << m_parameterName << "=" << param;

            m_parameterName = 0;

          }

        else

          {

            std::clog << param;

          }

        break;

      case 1:

        if (m_parameterName)

          {

            std::clog << ", " << m_parameterName << "=" << param;

            m_parameterName = 0;

          }

        else

          {

            std::clog << ", " << param;

          }

        break;

      default: // parameter following a previous parameter

        std::clog << ", " << param;

        break;

      }

    m_itemNumber++;

    return *this;

  }

  ParameterLogger&

  operator << (ParameterName paramName)

  {

    m_parameterName = paramName.name;

    return *this;

  }

  ParameterLogger&

  operator << (EndParameterListStruct dummy)

  {

    std::clog << ")" << std::endl;

    m_itemNumber = 0;

    return *this;

  }

};

extern ParameterLogger g_parameterLogger;

}

/**

 * \param level the log level

 * \param msg the message to log

 *

 * This macro allows you to log an arbitrary message at a specific

 * log level. The log message is expected to be a C++ ostream

 * message such as "my string" << aNumber << "my oth stream".

 *

 * Typical usage looks like:

 * \code

 * NS_LOG (LOG_DEBUG, "a number="<<aNumber<<", anotherNumber="<<anotherNumber);

 * \endcode

 */

#define NS_LOG(level, msg)                                      \

  do                                                            \

    {                                                           \

      if (g_log.IsEnabled (level))                              \

        {                                                       \

          if (g_log.IsEnabled (ns3::LOG_PREFIX_ALL))            \

            {                                                   \

              std::clog << g_log.Name () << ":" <<              \

                __FUNCTION__ << "(): ";                         \

            }                                                   \

          std::clog << msg << std::endl;                        \

        }                                                       \

    }                                                           \

  while (false)

#define NS_LOG_F(level)                                         \

  do                                                            \

    {                                                           \

      if (g_log.IsEnabled (level))                              \

        {                                                       \

          std::clog << g_log.Name () << ":" << __FUNCTION__ <<  \

            "()" << std::endl;                                \

        }                                                       \

    }                                                           \

  while (false)

#define NS_LOG_ERROR(msg) \

  NS_LOG(ns3::LOG_ERROR, msg)

#define NS_LOG_WARN(msg) \

  NS_LOG(ns3::LOG_WARN, msg)

#define NS_LOG_DEBUG(msg) \

  NS_LOG(ns3::LOG_DEBUG, msg)

#define NS_LOG_INFO(msg) \

  NS_LOG(ns3::LOG_INFO, msg)

#define NS_LOG_FUNCTION \

  NS_LOG_F(ns3::LOG_FUNCTION)

#define NS_LOG_PARAMS(parameters)                       \

  do                                                    \

    {                                                   \

      if (g_log.IsEnabled (ns3::LOG_PARAM))             \

        {                                               \

          g_parameterLogger << __PRETTY_FUNCTION__      \

                            << parameters               \

                            << EndParameterList;        \

        }                                               \

    }                                                   \

  while (false)

#define NS_LOG_PARAMS_BEGIN()                           \

      if (g_log.IsEnabled (ns3::LOG_PARAM))             \

        {                                               \

          g_parameterLogger << __PRETTY_FUNCTION__;

#define NS_LOG_PARAM(param) \

          g_parameterLogger << ParameterName (#param) << param;

#define NS_LOG_PARAMS_END()                             \

          g_parameterLogger << EndParameterList;        \

        }

#define NS_LOG_LOGIC(msg) \

  NS_LOG(ns3::LOG_LOGIC, msg)

#define NS_LOG_UNCOND(msg)              \

  do                                    \

    {                                   \

      std::clog << msg << std::endl;    \

    }                                   \

  while (false)

#else

#define NS_LOG(level, msg)

#define NS_LOG_F(level)

#define NS_LOG_ERROR(msg)

#define NS_LOG_WARN(msg)

#define NS_LOG_DEBUG(msg)

#define NS_LOG_INFO(msg)

#define NS_LOG_FUNCTION

#define NS_LOG_LOGIC(msg)

#define NS_LOG_UNCOND(msg)

#endif

namespace ns3 {

#ifdef NS3_LOG_ENABLE

enum LogLevel {

  LOG_NONE           = 0x00000000, // no logging

  LOG_ERROR          = 0x00000001, // serious error messages only

  LOG_LEVEL_ERROR    = 0x00000001,

  LOG_WARN           = 0x00000002, // warning messages

  LOG_LEVEL_WARN     = 0x00000003,

  LOG_DEBUG          = 0x00000004, // rare ad-hoc debug messages

  LOG_LEVEL_DEBUG    = 0x00000007,

  LOG_INFO           = 0x00000008, // informational messages (e.g., banners)

  LOG_LEVEL_INFO     = 0x0000000f,

  LOG_FUNCTION       = 0x00000010, // function tracing

  LOG_LEVEL_FUNCTION = 0x0000001f, 

  LOG_PARAM          = 0x00000020, // parameters to functions

  LOG_LEVEL_PARAM    = 0x0000003f,

  LOG_LOGIC          = 0x00000040, // control flow tracing within functions

  LOG_LEVEL_LOGIC    = 0x0000007f,

  LOG_ALL            = 0x7fffffff, // print everything

  LOG_LEVEL_ALL      = LOG_ALL,

  LOG_PREFIX_ALL     = 0x80000000  // prefix all trace prints with function

};

#endif

#ifdef NS3_LOG_ENABLE

/**

 * \param name a log component name

 * \param level a logging level

 * \ingroup logging

 *

 * Enable the logging output associated with that log component.

 * The logging output can be later disabled with a call

 * to ns3::LogComponentDisable.

 */

  void LogComponentEnable (char const *name, enum LogLevel level);

/**

 * \param level a logging level

 * \ingroup logging

 *

 * Enable the logging output for all registered log components.

 */

  void LogComponentEnableAll (enum LogLevel level);

#else

#define LogComponentEnable(a,b)

#define LogComponentEnableAll(a)

#endif

#ifdef NS3_LOG_ENABLE

/**

 * \param name a log component name

 * \param level a logging level

 * \ingroup logging

 *

 * Disable the logging output associated with that log component.

 * The logging output can be later re-enabled with a call

 * to ns3::LogComponentEnable.

 */

void LogComponentDisable (char const *name, enum LogLevel level);

/**

 * \param level a logging level

 * \ingroup logging

 *

 * Disable all logging for all components.

 */

void LogComponentDisableAll (enum LogLevel level);

#else

#define LogComponentDisable(a,b)

#define LogComponentDisableAll(a)

#endif

/**

 * \ingroup logging

 *

 * Print the list of logging messages available.

 */

#ifdef NS3_LOG_ENABLE

void LogComponentPrintList (void);

#else

#define LogComponentPrintList()

#endif

#ifdef NS3_LOG_ENABLE

class LogComponent {

public:

  LogComponent (char const *name);

  void EnvVarCheck (char const *name);

  bool IsEnabled (enum LogLevel level) const;

  bool IsNoneEnabled (void) const;

  void Enable (enum LogLevel level);

  void Disable (enum LogLevel level);

  bool Decorate (void) const;

  char const *Name (void) const;

private:

  int32_t     m_levels;

  char const *m_name;

  bool        m_decorate;

};

#endif

} // namespace ns3

#endif // __LOG_H__