#include "Peer.hpp"

#include "Replicator.hpp"
#include "RakNet/GetTime.hpp"
#include "RakNet/RakPeer.hpp"
#include "ConcurrentRakPeer.hpp"
#include "Log.hpp"

#include "Debug.hpp"

#include "DataModel/Stats.hpp"

#include "DataModel/DataModelJob.hpp"

#include "DataModel/PhysicsService.hpp"

#include "DataModel/DataModel.hpp"

#include "Utility/ObscureValue.hpp"

#include "Utility/StandardOut.hpp"


#include "DataBlockEncryptor.hpp"

const char* const Aya::Network::sPeer = "NetworkPeer";

namespace Aya
{
namespace Network
{


static Reflection::BoundFuncDesc<Peer, void(int)> func_SetOutgoingKBPSLimit(
    &Peer::setOutgoingKBPSLimit, "SetOutgoingKBPSLimit", "limit", Security::Plugin);
REFLECTION_END();

class ProfiledRakPeer : public RakNet::RakPeer
{
private:
    Peer& peer; // time spent per step in the Raknet thread
    typedef RakNet::RakPeer Super;

public:
    ProfiledRakPeer(Peer& peer)
        : peer(peer)
    {
    }
    virtual bool RunUpdateCycle(RakNet::TimeUS timeNS, RakNet::Time timeMS)
    {
        Timer<Time::Benchmark> timer;
        RakNet::BitStream updateBitStream(MAXIMUM_MTU_SIZE);
        bool result = Super::RunUpdateCycle(timeNS, timeMS, updateBitStream);
        peer.rakDutyCycle.sample(timer.delta());
        return result;
    }
};

static double lerp = 0.05;
unsigned char Peer::aesKey[16];

Peer::Peer()
    : rakDutyCycle(lerp)
{
    for (int i = 0; i < 16; ++i)
        aesKey[i] = 0xFE ^ 7 * i;

    protocolVersion = NETWORK_PROTOCOL_VERSION;
}

Peer::~Peer() {}

void Peer::onCreateRakPeer()
{
    RakNet::RakNetGUID guid = rakPeer->rawPeer()->GetGuidFromSystemAddress(RakNet::UNASSIGNED_SYSTEM_ADDRESS);
    unsigned int seed = (unsigned int)((guid.g >> 32) ^ guid.g);
    rnr.SeedMT(seed);

    rakPeer->rawPeer()->SetOccasionalPing(true);
}

void Peer::encryptDataPart(RakNet::BitStream& bitStream)
{
    DataBlockEncryptor encryptor;
    encryptor.SetKey(Peer::aesKey);

    unsigned int length = (unsigned int)bitStream.GetNumberOfBytesUsed() - 1;

    unsigned int bytesRequired = length + 6;
    bytesRequired = ((bytesRequired + 15) / 16) * 16;

    int deltaBits = 8 * bytesRequired - (bitStream.GetNumberOfBitsAllocated() - 8);
    if (deltaBits > 0)
        bitStream.AddBitsAndReallocate(deltaBits);

    encryptor.Encrypt((unsigned char*)bitStream.GetData() + 1, length, (unsigned char*)bitStream.GetData() + 1, &length, &rnr);
    bitStream.SetWriteOffset((1 + length) * 8);
}


void Peer::decryptDataPart(RakNet::BitStream& inBitstream)
{
    DataBlockEncryptor encryptor;
    encryptor.SetKey(Peer::aesKey);

    unsigned int length = (unsigned int)inBitstream.GetNumberOfBytesUsed() - 1;

    bool success = encryptor.Decrypt((unsigned char*)inBitstream.GetData() + 1, length, (unsigned char*)inBitstream.GetData() + 1, &length);
    if (!success)
        throw std::runtime_error("Data error");
}

bool Peer::askAddChild(const Instance* instance) const
{
    return Instance::fastDynamicCast<Replicator>(instance) != NULL;
}

class PeerStatsItem : public Stats::Item
{
    Peer* peer;
    Stats::Item* rakRate;
    Stats::Item* rakActivity;
    Stats::Item* physicsSenders;
    Stats::Item* bufferHealth;

public:
    PeerStatsItem(Peer* peer)
        : peer(peer)
    {
        Stats::Item* item =
            createChildItem("Packets Thread"); // TODO: Rename this when possible. Unfortunately, Game service requires this to be here
        rakRate = item->createChildItem("Rate");
        rakActivity = item->createChildItem("Activity");
        physicsSenders = item->createChildItem("Physics Senders"); // TODO: More this out of "Packets Thread" when we refactor Game Service
        bufferHealth = item->createChildItem("Send Buffer Health");
    }

    /* override */ void update()
    {
        rakActivity->formatPercent(peer->rakDutyCycle.dutyCycle());
        double rate = peer->rakDutyCycle.rate();
        rakRate->formatValue(rate, "%.2g/s", rate);

        PhysicsService* physicsService = ServiceProvider::find<PhysicsService>(this);
        physicsSenders->formatValue(physicsService ? physicsService->numSenders() : 0);

        double health = peer->rakPeer->GetBufferHealth();
        bufferHealth->formatValue(health, "%.4g", health);
    }
};


class PacketReceiveJob : public DataModelJob
{
    weak_ptr<DataModel> dataModel;
    ObscureValue<double> receiveRate;

public:
    weak_ptr<ConcurrentRakPeer> rakPeer;
    PacketReceiveJob(shared_ptr<ConcurrentRakPeer> rakPeer, DataModel* dataModel)
        : DataModelJob("Net PacketReceive", DataModelJob::DataIn, false, shared_from(dataModel), Time::Interval(0))
        , rakPeer(rakPeer)
        , dataModel(shared_from(dataModel))
        , receiveRate(NetworkSettings::singleton().getReceiveRate())
    {
        cyclicExecutive = true;
        cyclicPriority = CyclicExecutiveJobPriority_Network_ReceiveIncoming;
    }

private:
    Time::Interval sleepTime(const Stats& stats)
    {
        return computeStandardSleepTime(stats, receiveRate);
    }

    virtual Job::Error error(const Stats& stats)
    {
        return computeStandardError(stats, receiveRate);
    }


    virtual TaskScheduler::StepResult stepDataModelJob(const Stats& stats)
    {
        if (shared_ptr<DataModel> safeDataModel = dataModel.lock())
        {
            FASTLOG1(FLog::DataModelJobs, "Packet receive start, data model: %p", safeDataModel.get());
            DataModel::scoped_write_request request(safeDataModel.get());

            if (shared_ptr<ConcurrentRakPeer> safeRakPeer = rakPeer.lock())
                while (RakNet::Packet* packet = safeRakPeer->rawPeer()->Receive())
                    safeRakPeer->DeallocatePacket(packet);

            FASTLOG1(FLog::DataModelJobs, "Packet receive finish, data model: %p", safeDataModel.get());
            return TaskScheduler::Stepped;
        }
        return TaskScheduler::Done;
    }
};


void Peer::setOutgoingKBPSLimit(int limit)
{
    if (limit <= 0)
        rakPeer->rawPeer()->SetPerConnectionOutgoingBandwidthLimit(0);
    else
        rakPeer->rawPeer()->SetPerConnectionOutgoingBandwidthLimit(1000 * G3D::iClamp(limit, 10, 10000));
}

void Peer::onServiceProvider(ServiceProvider* oldProvider, ServiceProvider* newProvider)
{
    Aya::Stats::StatsService* stats = ServiceProvider::find<Aya::Stats::StatsService>(oldProvider);
    if (stats)
    {
        shared_ptr<Stats::Item> network = shared_from_polymorphic_downcast<Stats::Item>(stats->findFirstChildByName("Network"));
        if (network)
            network->setParent(NULL);
    }

    if (receiveJob)
    {
        receiveJob->rakPeer.reset(); // Make sure it doesn't try to run from now on. (The concurrency is such that it isn't running now)
        TaskScheduler::singleton().remove(receiveJob);
        receiveJob.reset();
    }

    // Ensure that all Replicators are removed, because they
    // point to rakPeer, which is about to be deleted
    this->removeAllChildren();

    if (rakPeer)
    {
        rakPeer->rawPeer()->DetachPlugin(this);
        rakPeer.reset();
    }

    Super::onServiceProvider(oldProvider, newProvider);

    if (newProvider)
    {
        rakPeer.reset(new ConcurrentRakPeer(new ProfiledRakPeer(*this), boost::polymorphic_downcast<DataModel*>(newProvider)));
        rakPeer->rawPeer()->AttachPlugin(this);
        // rakPeer->rawPeer()->SetMTUSize(1400);
        onCreateRakPeer();

        receiveJob = shared_ptr<PacketReceiveJob>(new PacketReceiveJob(rakPeer, boost::polymorphic_downcast<DataModel*>(newProvider)));
        TaskScheduler::singleton().add(receiveJob);
    }

    stats = ServiceProvider::find<Aya::Stats::StatsService>(newProvider);
    if (stats)
    {
        AYAASSERT(!shared_from_polymorphic_downcast<Stats::Item>(stats->findFirstChildByName("Network")));
        shared_ptr<Stats::Item> network = Creatable<Instance>::create<PeerStatsItem>(this);
        network->setName("Network");
        network->setParent(stats);
    }
}

} // namespace Network
} // namespace Aya