/*

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 *  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

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 */

#include <stdarg.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include "platform/nexus_core.hpp"

#include "platform/nexus_node.hpp"

namespace ot {

namespace Nexus {

class FuzzDataProvider

{

public:

    FuzzDataProvider(const uint8_t *aData, size_t aSize)

        : mData(aData)

        , mSize(aSize)

    {

    }

    void ConsumeData(void *aBuf, size_t aLength)

    {

        assert(aLength <= mSize);

        memcpy(aBuf, mData, aLength);

        mData += aLength;

        mSize -= aLength;

    }

    otError ConsumeRemainingBytes(otMessage *aMessage)

    {

        otError error;

        SuccessOrExit(error = otMessageAppend(aMessage, mData, static_cast<uint16_t>(mSize)));

        mSize = 0;

    exit:

        return error;

    }

    bool ConsumeBool(void)

    {

        assert(mSize > 0);

        uint8_t result;

        ConsumeData(&result, sizeof(result));

        return result & 1;

    }

    size_t RemainingBytes(void) { return mSize; }

private:

    const uint8_t *mData;

    size_t         mSize;

};

extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)

{

    const uint16_t kMaxMessageSize = 2048;

    FuzzDataProvider fdp(data, size);

    unsigned int      seed;

    otMessage        *message;

    otMessageSettings settings;

    if (size < sizeof(seed) + sizeof(settings.mLinkSecurityEnabled) + sizeof(settings.mPriority))

    {

        return 0;

    }

    if (size > sizeof(seed) + sizeof(settings.mLinkSecurityEnabled) + sizeof(settings.mPriority) + kMaxMessageSize)

    {

        return 0;

    }

    fdp.ConsumeData(&seed, sizeof(seed));

    srand(seed);

    Core nexus;

    Node &node = nexus.CreateNode();

    node.GetInstance().SetLogLevel(kLogLevelInfo);

    node.GetInstance().Get<BorderRouter::RoutingManager>().Init(/* aInfraIfIndex */ 1, /* aInfraIfIsRunning */ true);

    node.GetInstance().Get<BorderRouter::RoutingManager>().SetEnabled(true);

    node.GetInstance().Get<Srp::Server>().SetAutoEnableMode(true);

    node.GetInstance().Get<BorderRouter::RoutingManager>().SetDhcp6PdEnabled(true);

    node.GetInstance().Get<BorderRouter::RoutingManager>().SetNat64PrefixManagerEnabled(true);

    node.GetInstance().Get<Nat64::Translator>().SetEnabled(true);

    Log("---------------------------------------------------------------------------------------");

    Log("Form network");

    node.Form();

    nexus.AdvanceTime(60 * 1000);

    VerifyOrQuit(node.Get<Mle::Mle>().IsLeader());

    VerifyOrQuit(node.Get<Srp::Server>().GetState() == Srp::Server::kStateRunning);

    Log("---------------------------------------------------------------------------------------");

    Log("Fuzz");

    memset(&settings, 0, sizeof(settings));

    settings.mLinkSecurityEnabled = fdp.ConsumeBool();

    fdp.ConsumeData(&settings.mPriority, sizeof(settings.mPriority));

    message = otIp6NewMessage(&node.GetInstance(), &settings);

    VerifyOrExit(message != nullptr);

    SuccessOrQuit(fdp.ConsumeRemainingBytes(message));

    otIp6Send(&node.GetInstance(), message);

    nexus.AdvanceTime(10 * 1000);

exit:

    return 0;

}

} // namespace Nexus

} // namespace ot