/*
 *    Copyright (c) 2022, The OpenThread Authors.
 *    All rights reserved.
 *
 *    Redistribution and use in source and binary forms, with or without
 *    modification, are permitted provided that the following conditions are met:
 *    1. Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *    2. Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *    3. Neither the name of the copyright holder nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 *    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 *    ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 *    WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 *    DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY
 *    DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 *    (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *    LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 *    ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 *    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/**
 * @file
 *   This file implements infrastructure network interface.
 */

#include "infra_if.hpp"
#include "common/num_utils.hpp"

#if OPENTHREAD_CONFIG_BORDER_ROUTING_ENABLE

#include "instance/instance.hpp"

namespace ot {
namespace BorderRouter {

RegisterLogModule("InfraIf");

InfraIf::InfraIf(Instance &aInstance)
    : InstanceLocator(aInstance)
    , mInitialized(false)
    , mIsRunning(false)
    , mIfIndex(0)
{
}

void InfraIf::Init(uint32_t aInfraIfIndex, bool aInfraIfIsRunning)
{
    if (mInitialized)
    {
        VerifyOrExit(aInfraIfIndex != mIfIndex);

        LogInfo("Switching previously configured %s to %lu", ToString().AsCString(), ToUlong(aInfraIfIndex));

        // When switching interface index, we `Deinit()` to signal
        // that the previous `mIfIndex` is down so that all modules
        // operating on this interface are stopped before restarting
        // operation on the new interface.

        Deinit();
    }

    mIfIndex     = aInfraIfIndex;
    mInitialized = true;

    LogInfo("Init %s", ToString().AsCString());

    Get<RoutingManager>().Init();

exit:
    IgnoreError(HandleStateChanged(mIfIndex, aInfraIfIsRunning));
}

void InfraIf::Deinit(void)
{
    VerifyOrExit(mInitialized);

    LogInfo("Deinit %s", ToString().AsCString());

    IgnoreError(HandleStateChanged(mIfIndex, /* aIsRunning */ false));

    mInitialized = false;

exit:
    return;
}

bool InfraIf::HasAddress(const Ip6::Address &aAddress) const
{
    OT_ASSERT(mInitialized);

    return otPlatInfraIfHasAddress(&GetInstance(), mIfIndex, &aAddress);
}

Error InfraIf::Send(const Icmp6Packet &aPacket, const Ip6::Address &aDestination) const
{
    OT_ASSERT(mInitialized);

    return otPlatInfraIfSendIcmp6Nd(&GetInstance(), mIfIndex, &aDestination, aPacket.GetBytes(), aPacket.GetLength());
}

void InfraIf::HandledReceived(uint32_t aIfIndex, const Ip6::Address &aSource, const Icmp6Packet &aPacket)
{
    Error                    error = kErrorNone;
    const Ip6::Icmp::Header *icmp6Header;

    VerifyOrExit(mInitialized && mIsRunning, error = kErrorInvalidState);
    VerifyOrExit(aIfIndex == mIfIndex, error = kErrorDrop);
    VerifyOrExit(aPacket.GetBytes() != nullptr, error = kErrorInvalidArgs);
    VerifyOrExit(aPacket.GetLength() >= sizeof(Ip6::Icmp::Header), error = kErrorParse);

    icmp6Header = reinterpret_cast<const Ip6::Icmp::Header *>(aPacket.GetBytes());

    switch (icmp6Header->GetType())
    {
    case Ip6::Icmp::Header::kTypeRouterAdvert:
        Get<RxRaTracker>().HandleRouterAdvertisement(aPacket, aSource);
        break;
    case Ip6::Icmp::Header::kTypeNeighborAdvert:
        Get<RxRaTracker>().HandleNeighborAdvertisement(aPacket);
        break;
    case Ip6::Icmp::Header::kTypeRouterSolicit:
        Get<RoutingManager>().HandleRouterSolicit(aPacket, aSource);
        break;
    default:
        break;
    }

exit:
    LogDebgOnError(error, "process ICMPv6 msg");
}

#if OPENTHREAD_CONFIG_NAT64_BORDER_ROUTING_ENABLE

Error InfraIf::DiscoverNat64Prefix(void) const
{
    OT_ASSERT(mInitialized);

    return otPlatInfraIfDiscoverNat64Prefix(&GetInstance(), mIfIndex);
}

void InfraIf::DiscoverNat64PrefixDone(uint32_t aIfIndex, const Ip6::Prefix &aPrefix)
{
    Error error = kErrorNone;

    VerifyOrExit(mInitialized && mIsRunning, error = kErrorInvalidState);
    VerifyOrExit(aIfIndex == mIfIndex, error = kErrorInvalidArgs);

    Get<RoutingManager>().HandlePlatformDiscoveredNat64PrefixDone(aPrefix);

exit:
    LogDebgOnError(error, "handle discovered NAT64 synthetic addresses");
}

#endif // OPENTHREAD_CONFIG_NAT64_BORDER_ROUTING_ENABLE

Error InfraIf::GetLinkLayerAddress(LinkLayerAddress &aLinkLayerAddress)
{
    return otPlatGetInfraIfLinkLayerAddress(&GetInstance(), mIfIndex, &aLinkLayerAddress);
}

Error InfraIf::HandleStateChanged(uint32_t aIfIndex, bool aIsRunning)
{
    Error error = kErrorNone;

    VerifyOrExit(mInitialized, error = kErrorInvalidState);
    VerifyOrExit(aIfIndex == mIfIndex, error = kErrorInvalidArgs);

    VerifyOrExit(aIsRunning != mIsRunning);
    LogInfo("State changed: %sRUNNING -> %sRUNNING", mIsRunning ? "" : "NOT ", aIsRunning ? "" : "NOT ");

    mIsRunning = aIsRunning;

    Get<RxRaTracker>().HandleInfraIfStateChanged();

#if OPENTHREAD_CONFIG_BORDER_ROUTING_MULTI_AIL_DETECTION_ENABLE
    Get<MultiAilDetector>().HandleInfraIfStateChanged();
#endif

    Get<RoutingManager>().HandleInfraIfStateChanged();

#if OPENTHREAD_CONFIG_SRP_SERVER_ADVERTISING_PROXY_ENABLE
    Get<Srp::AdvertisingProxy>().HandleInfraIfStateChanged();
#endif

#if OPENTHREAD_CONFIG_DNSSD_SERVER_ENABLE && OPENTHREAD_CONFIG_DNSSD_DISCOVERY_PROXY_ENABLE
    Get<Dns::ServiceDiscovery::Server>().HandleInfraIfStateChanged();
#endif

#if OPENTHREAD_CONFIG_MULTICAST_DNS_ENABLE
    Get<Dns::Multicast::Core>().HandleInfraIfStateChanged();
#endif

exit:
    return error;
}

#if OPENTHREAD_CONFIG_BORDER_ROUTING_DHCP6_PD_ENABLE && OPENTHREAD_CONFIG_BORDER_ROUTING_DHCP6_PD_CLIENT_ENABLE

void InfraIf::SetDhcp6ListeningEnabled(bool aEnable)
{
    otPlatInfraIfDhcp6PdClientSetListeningEnabled(&GetInstance(), aEnable, mIfIndex);
}

void InfraIf::SendDhcp6(Message &aMessage, Ip6::Address &aDestAddress)
{
    otPlatInfraIfDhcp6PdClientSend(&GetInstance(), &aMessage, &aDestAddress, mIfIndex);
}

void InfraIf::HandleDhcp6Received(Message &aMessage, uint32_t aInfraIfIndex)
{
    Error error = kErrorNone;

    VerifyOrExit(mInitialized && mIsRunning, error = kErrorInvalidState);
    VerifyOrExit(aInfraIfIndex == mIfIndex, error = kErrorDrop);

    Get<Dhcp6PdClient>().HandleReceived(aMessage);

exit:
    LogDebgOnError(error, "process DHCPv6 msg");
}

#endif // OPENTHREAD_CONFIG_BORDER_ROUTING_DHCP6_PD_ENABLE && OPENTHREAD_CONFIG_BORDER_ROUTING_DHCP6_PD_CLIENT_ENABLE

InfraIf::InfoString InfraIf::ToString(void) const
{
    InfoString string;

    string.Append("infra netif %lu", ToUlong(mIfIndex));
    return string;
}

//---------------------------------------------------------------------------------------------------------------------
// InfraIf::LinkLayerAddress

Error InfraIf::LinkLayerAddress::ConvertToIid(Ip6::InterfaceIdentifier &aIid) const
{
    Error           error = kErrorNone;
    Mac::ExtAddress extAddress;

    switch (mLength)
    {
    case 5:
        // EUI-40 - [AA BB] + [FF FF FE] + [CC DD EE]
        extAddress.m8[0] = mAddress[0];
        extAddress.m8[1] = mAddress[1];
        extAddress.m8[2] = 0xff;
        extAddress.m8[3] = 0xff;
        extAddress.m8[4] = 0xfe;
        extAddress.m8[5] = mAddress[2];
        extAddress.m8[6] = mAddress[3];
        extAddress.m8[7] = mAddress[4];
        break;

    case 6:
        // EUI-48 - [AA BB CC] + [FF FE] + [DD EE FF]
        extAddress.m8[0] = mAddress[0];
        extAddress.m8[1] = mAddress[1];
        extAddress.m8[2] = mAddress[2];
        extAddress.m8[3] = 0xff;
        extAddress.m8[4] = 0xfe;
        extAddress.m8[5] = mAddress[3];
        extAddress.m8[6] = mAddress[4];
        extAddress.m8[7] = mAddress[5];
        break;

    case 8:
        extAddress.Set(mAddress);
        break;

    default:
        ExitNow(error = kErrorNotCapable);
    }

    aIid.InitFromExtAddress(extAddress);

exit:
    return error;
}

InfraIf::LinkLayerAddress::InfoString InfraIf::LinkLayerAddress::ToString(void) const
{
    InfoString string;

    for (uint8_t i = 0; i < GetLength(); i++)
    {
        if (i > 0)
        {
            string.Append(":");
        }

        string.Append("%02x", mAddress[i]);
    }

    return string;
}

//---------------------------------------------------------------------------------------------------------------------

extern "C" void otPlatInfraIfRecvIcmp6Nd(otInstance         *aInstance,
                                         uint32_t            aInfraIfIndex,
                                         const otIp6Address *aSrcAddress,
                                         const uint8_t      *aBuffer,
                                         uint16_t            aBufferLength)
{
    InfraIf::Icmp6Packet packet;

    packet.Init(aBuffer, aBufferLength);
    AsCoreType(aInstance).Get<InfraIf>().HandledReceived(aInfraIfIndex, AsCoreType(aSrcAddress), packet);
}

extern "C" otError otPlatInfraIfStateChanged(otInstance *aInstance, uint32_t aInfraIfIndex, bool aIsRunning)
{
    return AsCoreType(aInstance).Get<InfraIf>().HandleStateChanged(aInfraIfIndex, aIsRunning);
}

extern "C" void otPlatInfraIfDiscoverNat64PrefixDone(otInstance        *aInstance,
                                                     uint32_t           aInfraIfIndex,
                                                     const otIp6Prefix *aIp6Prefix)
{
#if OPENTHREAD_CONFIG_NAT64_BORDER_ROUTING_ENABLE
    AsCoreType(aInstance).Get<InfraIf>().DiscoverNat64PrefixDone(aInfraIfIndex, AsCoreType(aIp6Prefix));
#else
    OT_UNUSED_VARIABLE(aInstance);
    OT_UNUSED_VARIABLE(aInfraIfIndex);
    OT_UNUSED_VARIABLE(aIp6Prefix);
#endif
}

#if OPENTHREAD_CONFIG_BORDER_ROUTING_DHCP6_PD_ENABLE && OPENTHREAD_CONFIG_BORDER_ROUTING_DHCP6_PD_CLIENT_ENABLE
extern "C" void otPlatInfraIfDhcp6PdClientHandleReceived(otInstance *aInstance,
                                                         otMessage  *aMessage,
                                                         uint32_t    aInfraIfIndex)
{
    AsCoreType(aInstance).Get<InfraIf>().HandleDhcp6Received(AsCoreType(aMessage), aInfraIfIndex);
}
#endif

} // namespace BorderRouter
} // namespace ot

//---------------------------------------------------------------------------------------------------------------------

#if OPENTHREAD_CONFIG_BORDER_ROUTING_MOCK_PLAT_APIS_ENABLE
OT_TOOL_WEAK bool otPlatInfraIfHasAddress(otInstance *, uint32_t, const otIp6Address *) { return false; }

OT_TOOL_WEAK otError otPlatInfraIfSendIcmp6Nd(otInstance *, uint32_t, const otIp6Address *, const uint8_t *, uint16_t)
{
    return OT_ERROR_FAILED;
}

OT_TOOL_WEAK otError otPlatInfraIfDiscoverNat64Prefix(otInstance *, uint32_t) { return OT_ERROR_FAILED; }
#endif

extern "C" OT_TOOL_WEAK otError otPlatGetInfraIfLinkLayerAddress(otInstance *,
                                                                 uint32_t,
                                                                 otPlatInfraIfLinkLayerAddress *)
{
    return OT_ERROR_FAILED;
}

#endif // OPENTHREAD_CONFIG_BORDER_ROUTING_ENABLE
