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 *     notice, this list of conditions and the following disclaimer in the
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 *     names of its contributors may be used to endorse or promote products
 *     derived from this software without specific prior written permission.
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/**
 * @file
 *   This file includes definitions of the posix Netif of otbr-agent.
 */

#ifndef OTBR_AGENT_POSIX_NETIF_HPP_
#define OTBR_AGENT_POSIX_NETIF_HPP_

#include <net/if.h>

#include <functional>
#include <vector>

#include <openthread/ip6.h>

#include "common/mainloop.hpp"
#include "common/types.hpp"

namespace otbr {

class Netif
{
public:
    using Ip6SendFunc = std::function<otbrError(const uint8_t *, uint16_t)>;

    Netif(void);

    otbrError Init(const std::string &aInterfaceName, const Ip6SendFunc &aIp6SendFunc);
    void      Deinit(void);

    void      Process(const MainloopContext *aContext);
    void      UpdateFdSet(MainloopContext *aContext);
    void      UpdateIp6UnicastAddresses(const std::vector<Ip6AddressInfo> &aAddrInfos);
    otbrError UpdateIp6MulticastAddresses(const std::vector<Ip6Address> &aAddrs);
    void      SetNetifState(bool aState);

    void Ip6Receive(const uint8_t *aBuf, uint16_t aLen);

private:
    // TODO: Retrieve the Maximum Ip6 size from the coprocessor.
    static constexpr size_t kIp6Mtu = 1280;

    void Clear(void);

    otbrError CreateTunDevice(const std::string &aInterfaceName);
    otbrError InitNetlink(void);

    void      PlatformSpecificInit(void);
    void      SetAddrGenModeToNone(void);
    void      ProcessUnicastAddressChange(const Ip6AddressInfo &aAddressInfo, bool aIsAdded);
    otbrError ProcessMulticastAddressChange(const Ip6Address &aAddress, bool aIsAdded);
    void      ProcessIp6Send(void);

    int      mTunFd;           ///< Used to exchange IPv6 packets.
    int      mIpFd;            ///< Used to manage IPv6 stack on the network interface.
    int      mNetlinkFd;       ///< Used to receive netlink events.
    uint32_t mNetlinkSequence; ///< Netlink message sequence.

    unsigned int mNetifIndex;
    std::string  mNetifName;

    std::vector<Ip6AddressInfo> mIp6UnicastAddresses;
    std::vector<Ip6Address>     mIp6MulticastAddresses;
    Ip6SendFunc                 mIp6SendFunc;
};

} // namespace otbr

#endif // OTBR_AGENT_POSIX_NETIF_HPP_