FeatherMC/src/DedicatedServer.cpp

#include "DedicatedServer.h"
#include "config/ServerProperties.h"
#include "data/Registry.h"

#include "PacketReader.h"

#include <chrono>
#include <string>

using std::string;

namespace Feather
{
    DedicatedServer::DedicatedServer(ServerProperties* properties) :
        m_properties(properties),
        m_listener(properties->serverPort.GetValue(), this),
        m_status()
    {
        m_status.descriptionText = properties->motd.GetValue();
        m_status.maxPlayers = properties->maxPlayers;
     
        Registry::Init();

        m_worldManager.LoadWorld(m_properties->levelName);

        while (1)
        {
            auto [clients, clientsLock] = m_clients.borrow();
            for (auto& client : clients)
            {
                auto [data, clientLock] = client.GetTCPClient()->GetData().borrow();
                if (data.empty())
                    continue;
                uint32_t offset = 0;
                while (offset != data.size())
                {
                    auto reader = PacketReader(&data[offset]);
                    Protocol::ProcessPacket(*this, client, reader, client.GetContext().GetState());
                    offset += reader.Size();
                }
                data.clear();
            }

            // TODO: Move to tick thread !!
            {
                using namespace Protocol;
                using namespace std::chrono;

                // TODO: high_resolution_clock on mingw is innacurate and slow
                static auto lastKeepAlive = high_resolution_clock::now();
                auto now = high_resolution_clock::now();
                milliseconds td = duration_cast<milliseconds>(now - lastKeepAlive);

                if (td >= 1000ms) {
                    lastKeepAlive = now;

                    Play::ClientboundKeepAlive keepAlive =
                    {
                        // MC probably sends time since epoch
                        .id = duration_cast<milliseconds>(now.time_since_epoch()).count(),
                    };

                    for (auto &client : clients)
                    {
                        client.SendMessage(keepAlive);
                    }
                }
            }
        }
    }

    DedicatedServer::~DedicatedServer()
    {
    }

    void DedicatedServer::OnClientConnect(Network::TCPClientHandle&& client)
    {
        const auto& address = client->GetAddress();
        Log::Info("New connection from {}:{}", address.ip, address.port);

        auto [clients, lock] = m_clients.borrow();
        clients.emplace_back(std::move(client));
    }

    void DedicatedServer::OnClientDisconnect(const Network::TCPClient* client)
    {
        const auto& address = client->GetAddress();
        Log::Info("Disconnected from {}:{}", address.ip, address.port);

        auto [clients, lock] = m_clients.borrow();
        clients.remove_if([&](MinecraftClient& other) { return other.GetTCPClient().get() == client; });
    }

    using namespace Protocol;

    void DedicatedServer::HandleUnknownPacket(MinecraftClient &client, int32_t id, const PacketReader &packet)
    {
        Log::Trace("Got unknown packet with ID {} from client.", id);
    }

    void DedicatedServer::HandleLegacyPing(MinecraftClient& client)
    {
        Log::Info("Got legacy server list ping.");
    }

#pragma region Handshake & Status

    template <>
    void DedicatedServer::HandlePacket(MinecraftClient& client, const Handholding::ServerboundHandshake& handshake)
    {
        Log::Info("Client Intention Packet: version={}, serverIp={}, port={}, intention={}\n",
            handshake.protocolVersion,
            handshake.serverIP.c_str(),
            handshake.port,
            handshake.intention
        );

        client.GetContext().SetState(handshake.intention);
    }

    template <>
    void DedicatedServer::HandlePacket(MinecraftClient& client, const Status::ServerboundRequest& request)
    {
        Log::Info("Client sent STATUS_PING_REQUEST");

        Status::ClientboundResponse message =
        {
            .jsonResponse = m_status.GetServerStatusJSON()
        };

        client.SendMessage(message);
    }

    template <>
    void DedicatedServer::HandlePacket(MinecraftClient& client, const Status::ServerboundPing& ping)
    {
        Log::Info("Client sent STATUS_PING: {}", ping.timestamp);

        Status::ClientboundPong message =
        {
            .timestamp = ping.timestamp
        };

        client.SendMessage(message);
    }

#pragma endregion

    template <>
    void DedicatedServer::HandlePacket(MinecraftClient& client,const Login::ServerboundStart& start)
    {
        //Login::ClientboundSuccess success =
        //{
        //    .uuid = { 4658857991808325907ull, 7518717155607718277ull },
        //    .username = start.username
        //};
        std::string uuid = "ecb99913-96a8-40a7-8529-a2ca6ad95768";
        Login::ClientboundSuccess success =
        {
            .uuid = uuid,
            .username = start.username
        };

        client.SendMessage(success);
        client.GetContext().SetState(ProtocolState::Play);

        std::string type = "default";
        Play::ClientboundJoinGame join =
        {
            .entityId  = 0,
            .gamemode  = 0,
            .dimension = 0,
            .seedHash  = 0,
            .maxPlayers = uint8_t(m_properties->maxPlayers.GetValue()),
            .levelType  = type,
            .viewDistance = m_properties->viewDistance,
            .reducedDebugInfo = false,
            .enableRespawnScreen = true
        };

        client.SendMessage(join);

        Play::ClientboundSpawnPosition spawnPos =
        {
            .location = BlockPos(0, 64, 0),
        };

        client.SendMessage(spawnPos);

        using RelativeFlags = Play::ClientboundPlayerPositionAndLook::RelativeFlags;

        Play::ClientboundPlayerPositionAndLook playerPos = 
        {
            .x = 0,
            .y = 70,
            .z = 0,
            .xRot = 0,
            .yRot = 0,
            .flags = (RelativeFlags)0,
            .id = 0,
        };

        client.SendMessage(playerPos);


        NetworkMessage chunkData(5KB);
        // Packet ID
        chunkData.WriteVarInt(0x22);

        // Chunk X, Z
        chunkData.Write<int32_t>(-10);
        chunkData.Write<int32_t>(-12);

        // Full chunk
        chunkData.Write(true);


        Chunk* chunk = m_worldManager.GetOverworld()->m_chunk;

        NBT::CompoundTag* chunkNBT = m_worldManager.GetOverworld()->m_chunkNBT;

        int32_t sectionsBits = 0;

        NetworkMessage sections(3KB);

        for (int i = 0; i < Chunk::NUM_SECTIONS; i++)
        {
            ChunkSection sect = chunk->sections[i];

            Log::Trace("Chunk: Got Section {} with local palette size {}", i, sect.localPalette.Size());

            sectionsBits |= 1 << i;

            // Block Count: fudge
            sections.Write<uint16_t>(1024);
            
            // Bits Per Block
            sections.Write<uint8_t>(4);

            // Palette

            NetworkMessage paletteData(512);

            for (int i = 0; i < sect.localPalette.Size(); i++)
            {
                int id = sect.localPalette.ByID(i);
                Log::Trace("Palette: {} -> {}", i, id);

                paletteData.WriteVarInt(id);

                i++;
            }

            paletteData.Finalize();
            sections.WriteData(paletteData.GetData(), paletteData.GetDataSize());

            // Block Data
            //NBT::LongArrayTag blocks = sect.Get<NBT::LongArrayTag>("BlockStates");

            sections.WriteVarInt(ChunkSection::NUM_LONGS);
            sections.WriteData(sect.blockStates, ChunkSection::NUM_LONGS * sizeof(int64_t));
        }

        //Log::Trace("Section bits: {:#b}", sectionsBits);

        chunkData.WriteVarInt(sectionsBits);

        // Heightmaps
        // TODO: Use chunk->heightmaps
        NBT::DataBuffer buf = chunkNBT->Get<NBT::CompoundTag>("Heightmaps").GetData();
        chunkData.WriteData(buf.data, buf.length);

        // Biomes
        for (int i = 0; i < 1024; i++)
            chunkData.Write<int32_t>(5);
        //NBT::IntArrayTag biomes = chunk->Get<NBT::IntArrayTag>("Biomes");
        //NBT::DataBuffer buf1 = biomes.GetData();
        //chunkData.WriteData(buf1.data, buf1.length);

        sections.Finalize();
        chunkData.WriteVarInt(sections.GetDataSize());
        chunkData.WriteData(sections.GetData(), sections.GetDataSize());

        // Block Ents
        chunkData.WriteVarInt(0);

        chunkData.Finalize();
        client.SendMessage(chunkData);

    }

    template <>
    void DedicatedServer::HandlePacket(MinecraftClient& client, const Play::ServerboundKeepAlive& keepAlive)
    {
        // TODO: check these and kick clients that don't send em right or at all
    }
}