/*
 * Copyright (c) 2020 Universita' degli Studi di Napoli Federico II
 *
 * 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: Stefano Avallone <stavallo@unina.it>
 */

#ifndef WIFI_PROTECTION_H
#define WIFI_PROTECTION_H

#include "ctrl-headers.h"
#include "wifi-tx-vector.h"

#include "ns3/nstime.h"

#include <memory>

namespace ns3
{

/**
 * \ingroup wifi
 *
 * WifiProtection is an abstract base struct. Each derived struct defines a protection
 * method and stores the information needed to perform protection according to
 * that method.
 */
struct WifiProtection
{
    /**
     * \enum Method
     * \brief Available protection methods
     */
    enum Method
    {
        NONE = 0,
        RTS_CTS,
        CTS_TO_SELF
    };

    /**
     * Constructor.
     * \param m the protection method for this object
     */
    WifiProtection(Method m);
    virtual ~WifiProtection();

    /**
     * Clone this object.
     * \return a pointer to the cloned object
     */
    virtual std::unique_ptr<WifiProtection> Copy() const = 0;

    /**
     * \brief Print the object contents.
     * \param os output stream in which the data should be printed.
     */
    virtual void Print(std::ostream& os) const = 0;

    const Method method; //!< protection method
    Time protectionTime; //!< time required by the protection method
};

/**
 * \ingroup wifi
 *
 * WifiNoProtection specifies that no protection method is used.
 */
struct WifiNoProtection : public WifiProtection
{
    WifiNoProtection();

    std::unique_ptr<WifiProtection> Copy() const override;
    void Print(std::ostream& os) const override;
};

/**
 * \ingroup wifi
 *
 * WifiRtsCtsProtection specifies that RTS/CTS protection method is used.
 */
struct WifiRtsCtsProtection : public WifiProtection
{
    WifiRtsCtsProtection();

    std::unique_ptr<WifiProtection> Copy() const override;
    void Print(std::ostream& os) const override;

    WifiTxVector rtsTxVector; //!< RTS TXVECTOR
    WifiTxVector ctsTxVector; //!< CTS TXVECTOR
};

/**
 * \ingroup wifi
 *
 * WifiCtsToSelfProtection specifies that CTS-to-self protection method is used.
 */
struct WifiCtsToSelfProtection : public WifiProtection
{
    WifiCtsToSelfProtection();

    std::unique_ptr<WifiProtection> Copy() const override;
    void Print(std::ostream& os) const override;

    WifiTxVector ctsTxVector; //!< CTS TXVECTOR
};

/**
 * \brief Stream insertion operator.
 *
 * \param os the output stream
 * \param protection the protection method
 * \returns a reference to the stream
 */
std::ostream& operator<<(std::ostream& os, const WifiProtection* protection);

} // namespace ns3

#endif /* WIFI_PROTECTION_H */
