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

/*

 * Copyright (c) 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 DEFAULT_VALUE_H

#define DEFAULT_VALUE_H

#include <string>

#include <list>

#include "callback.h"

/**

 * \defgroup config Simulation configuration

 *

 */

namespace ns3 {

namespace DefaultValue

{

/**

 * \ingroup config

 * \param name name of variable to bind

 * \param value value to bind to the specified variable

 *

 * If the variable name does not match any existing

 * variable or if the value is not compatible with

 * the variable type, this function will abort

 * at runtime and print an error message detailing

 * which variable or value triggered the problem.

 */

void Bind (std::string name, std::string value);

}

class DefaultValueBase

{

public:

  virtual ~DefaultValueBase ();

  std::string GetName (void) const;

  std::string GetHelp (void) const;

  /**

   * \returns true if this value is dirty, false otherwise.

   *

   * A value becomes dirty when ParseValue is invoked

   * and it successfully completes. Dirtyness indicates

   * that the state of the value was changed by a user.

   */

  bool IsDirty (void) const;

  /**

   * Clear the dirty state.

   */

  void ClearDirtyFlag (void);

  // parse a matching parameter

  // return true in case of success, false otherwise.

  bool ParseValue (const std::string &value);

  std::string GetType (void) const;

  std::string GetDefaultValue (void) const;

protected:

  DefaultValueBase (const std::string &name, 

		    const std::string &help);

private:

  DefaultValueBase ();

private:

  virtual bool DoParseValue (const std::string &value) = 0;

  virtual std::string DoGetType (void) const = 0;

  virtual std::string DoGetDefaultValue (void) const = 0;

  std::string m_name;

  std::string m_help;

  bool m_dirty;

};

class DefaultValueList

{

 public:

  typedef std::list<DefaultValueBase *>::iterator Iterator;

  static Iterator Begin (void);

  static Iterator End (void);

  static void Remove (const std::string &name);

  static void Add (DefaultValueBase *defaultValue);

 private:

  typedef std::list<DefaultValueBase *> List;

  static List *GetList (void);

};

/**

 * \brief A Boolean variable for ns3::Bind

 * \ingroup config

 *

 * Every instance of this type is automatically 

 * registered in the variable pool which is used

 * by ns3::Bind. 

 */

class BooleanDefaultValue : public DefaultValueBase

{

public:

  /**

   * \param name name of variable

   * \param help help text which explains the purpose

   *        and the semantics of this variable

   * \param defaultValue the default value to assign

   *        to this variable.

   *

   * Unless the user invokes ns3::Bind with the right arguments,

   * the GetValue method will return the default value. Otherwise,

   * it will return the user-specified value.

   */

  BooleanDefaultValue (std::string name,

		       std::string help,

		       bool defaultValue);

  /**

   * \returns the default value for this variable or a

   *          user-provided overriden variable.

   */

  bool GetValue (void) const;

private:

  virtual bool DoParseValue (const std::string &value);

  virtual std::string DoGetType (void) const;

  virtual std::string DoGetDefaultValue (void) const;

  bool m_defaultValue;

  bool m_value;

};

/**

 * \brief A Numeric variable for ns3::Bind

 * \ingroup config

 *

 * Every instance of this type is automatically 

 * registered in the variable pool which is used

 * by ns3::Bind. 

 */

template <typename T>

class NumericDefaultValue : public DefaultValueBase

{

public:

  /**

   * \param name the name of the variable

   * \param help help text which explains the purpose

   *        and the semantics of this variable

   * \param defaultValue the default value assigned

   *        to this variable

   *

   * By default, the set of allowed values is the entire range

   * of values which can be stored and retrieved from the underlying

   * type.

   */

  NumericDefaultValue (std::string name,

		       std::string help,

		       T defaultValue);

  /**

   * \param name the name of the variable

   * \param help help text which explains the purpose

   *        and the semantics of this variable

   * \param defaultValue the default value assigned to this

   *        variable

   * \param minValue the minimum value which can be set

   *        in this variable

   */

  NumericDefaultValue (std::string name,

		       std::string help,

		       T defaultValue,

		       T minValue);

  /**

   * \param name the name of the variable

   * \param help help text which explains the purpose

   *        and the semantics of this variable

   * \param defaultValue the default value assigned to this

   *        variable

   * \param minValue the minimum value which can be set

   *        in this variable

   * \param maxValue the maximum value which can be set in this

   *        variable.

   */

  NumericDefaultValue (std::string name,

		       std::string help,

		       T defaultValue,

		       T minValue,

		       T maxValue);

  void SetValue (T v);

  T GetValue (void) const;

private:

  virtual bool DoParseValue (const std::string &value);

  virtual std::string DoGetType (void) const;

  virtual std::string DoGetDefaultValue (void) const;

  T m_defaultValue;

  T m_minValue;

  T m_maxValue;

  T m_value;

};

/**

 * \brief Named enumeration defaults

 * \ingroup config

 *

 * Every instance of this type is automatically 

 * registered in the variable pool which is used

 * by ns3::Bind. 

 */

class StringEnumDefaultValue : public DefaultValueBase

{

public:

  /**

   * \param name The name of the variable

   * \param help The help string

   */

  StringEnumDefaultValue (const std::string &name,

                          const std::string &help);

  /**

   * \brief Add a default value to this enumeration of strings

   * \param value The string to make the default for this

   */

  void AddDefaultValue (const std::string &value);

  /**

   * \brief Add a possible value to accept for this default value

   */

  void AddPossibleValue (const std::string &value);

  /**

   * \brief Get the value of this default value.

   * \return The string that has been assigned to this default value, either by

   * Bind() or by a command line setting

   */

  std::string GetValue (void) const;

private:

  virtual bool DoParseValue (const std::string &value);

  virtual std::string DoGetType (void) const;

  virtual std::string DoGetDefaultValue (void) const;

  bool m_oneDefault;

  std::list<std::string> m_possibleValues;

  std::string m_defaultValue;

  std::string m_value;

};

/**

 * \brief An enum variable for ns3::Bind

 * \ingroup config

 *

 * Every instance of this type is automatically 

 * registered in the variable pool which is used

 * by ns3::Bind. 

 */

template <typename T>

class EnumDefaultValue : public DefaultValueBase

{

public:

  /**

   * \param name the name of this variable

   * \param help help text which explains the purpose

   *        and the semantics of this variable

   * \param defaultValue the default value assigned to this

   *        variable unless it is overriden with ns3::Bind

   * \param defaultValueString the string which represents

   *        the default value which should be used by ns3::Bind

   *

   * This method takes a variable number of arguments. The list of

   * arguments is terminated by the pair of values 0 and (void *)0.

   * Each pair of extra argument is assumed to be of the form 

   * (enum value, string representing enum value). If ns3::Bind

   * is invoked on this variable, it will check that the user-provided

   * values are within the set of values specified in this constructor.

   *

   * Typical useage of this method will look like this:

   * \code

   * enum MyEnum {

   *   MY_ENUM_A,

   *   MY_ENUM_B,

   *   MY_ENUM_C,

   * };

   * // set default value to be "B".

   * static EnumDefaultValue<enum MyEnum> 

   *  g_myDefaultValue ("my", "my help",

   *                    MY_ENUM_B, "B",

   *                    MY_ENUM_A, "A",

   *                    MY_ENUM_C, "C",);

   *                    0, (void*)0);

   * \endcode

   * Note that to ensure portability to 64 bit systems, make sure that

   * the last element in the variable list of arguments is (void *)0.

   */

  EnumDefaultValue (const std::string &name, const std::string &help,

		    T defaultValue, const char *defaultValueString, 

		    ...);

  void AddPossibleValue (T value, const std::string &valueString);

  /**

   * \returns the default value or any other value specified by the 

   *          user with ns3::Bind

   */

  T GetValue (void);

  /**

   * \param value the new default value.

   */

  void SetValue (T value);

 private:

  virtual bool DoParseValue (const std::string &value);

  virtual std::string DoGetType (void) const;

  virtual std::string DoGetDefaultValue (void) const;

  typedef std::list<std::pair<T,std::string> > PossibleValues;

  T m_defaultValue;

  PossibleValues m_possibleValues;

  T m_value;

};

/**

 * \brief Class used to call a certain function during the configuration of the

 * simulation

 * \ingroup config

 */

class CommandDefaultValue : public DefaultValueBase

{

public:

  CommandDefaultValue (const std::string &name,

		       const std::string &help,

		       Callback<void> cb);

private:

  virtual bool DoParseValue (const std::string &value);

  virtual std::string DoGetType (void) const;

  virtual std::string DoGetDefaultValue (void) const;

  Callback<void> m_cb;

};

}//namespace ns3

#include "type-name.h"

#include "assert.h"

#include <sstream>

#include <stdarg.h>

#include <limits>

namespace ns3 {

/**************************************************************

 **************************************************************/

template <typename T>

NumericDefaultValue<T>::NumericDefaultValue (std::string name,

					     std::string help,

					     T defaultValue)

  : DefaultValueBase (name, help),

    m_defaultValue (defaultValue),

    m_minValue (std::numeric_limits<T>::min ()),

    m_maxValue (std::numeric_limits<T>::max ()),

    m_value (defaultValue)

{

  DefaultValueList::Add (this);

  NS_ASSERT (m_minValue < m_maxValue);

}

template <typename T>

NumericDefaultValue<T>::NumericDefaultValue (std::string name,

					     std::string help,

					     T defaultValue,

					     T minValue)

  : DefaultValueBase (name, help),

    m_defaultValue (defaultValue),

    m_minValue (minValue),

    m_maxValue (std::numeric_limits<T>::max ()),

    m_value (defaultValue)

{

  DefaultValueList::Add (this);

  NS_ASSERT (m_minValue < m_maxValue);

  NS_ASSERT (m_defaultValue <= m_maxValue &&

	     m_defaultValue >= m_minValue);

}

template <typename T>

NumericDefaultValue<T>::NumericDefaultValue (std::string name,

					     std::string help,

					     T defaultValue,

					     T minValue,

					     T maxValue)

  : DefaultValueBase (name, help),

    m_defaultValue (defaultValue),

    m_minValue (minValue),

    m_maxValue (maxValue),

    m_value (defaultValue)

{

  DefaultValueList::Add (this);

  NS_ASSERT (m_minValue < m_maxValue);

  NS_ASSERT (m_defaultValue <= m_maxValue &&

	     m_defaultValue >= m_minValue);

}

template <typename T>

void 

NumericDefaultValue<T>::SetValue (T v)

{

  NS_ASSERT (v <= m_maxValue &&

	     v >= m_minValue);

  m_value = v;

}

template <typename T>

T

NumericDefaultValue<T>::GetValue (void) const

{

  return m_value;

}

template <typename T>

bool

NumericDefaultValue<T>::DoParseValue (const std::string &value)

{

  std::istringstream iss;

  iss.str (value);

  iss >> m_value;

  if (m_value > m_maxValue ||

      m_value < m_minValue)

    {

      return false;

    }

  return !iss.bad () && !iss.fail ();

}

template <typename T>

std::string

NumericDefaultValue<T>::DoGetType (void) const

{

  std::ostringstream oss;

  oss << TypeNameGet<T> () << "("

      << m_minValue << ":" 

      << m_maxValue << ")";

  return oss.str ();

}

template <typename T>

std::string

NumericDefaultValue<T>::DoGetDefaultValue (void) const

{

  std::ostringstream oss;

  oss << m_defaultValue;

  return oss.str ();

}

/**************************************************************

 **************************************************************/

template <typename T>

EnumDefaultValue<T>::EnumDefaultValue (const std::string &name, const std::string &help,

				       T defaultValue, const char *defaultValueString, 

				       ...)

  : DefaultValueBase (name, help),

    m_defaultValue (defaultValue),

    m_value (defaultValue)

{

  AddPossibleValue (defaultValue, defaultValueString);

  va_list list;

  va_start (list, defaultValueString);

  while (true)

    {

      T v = (T) va_arg (list, int);

      const char *str = va_arg (list, const char *);

      if (v == 0 && str == 0)

	{

	  break;

	}

      AddPossibleValue (v, str);

    }

  DefaultValueList::Add (this);

}

template <typename T>

void 

EnumDefaultValue<T>::AddPossibleValue (T value, const std::string &valueString)

{

  m_possibleValues.push_back (std::make_pair (value, valueString));

}

template <typename T>

T 

EnumDefaultValue<T>::GetValue (void)

{

  return m_value;

}

template <typename T>

void

EnumDefaultValue<T>::SetValue (T value)

{