kolyah-game-2025/src/Multiplayer.cpp

#include "Multiplayer.hpp"

#include <cstdio>
#include <cstring>
#include <cctype>
#include <algorithm>
#include "Game.hpp"

// #define SERVER_ADDRESS "127.0.0.1"
#define SERVER_ADDRESS "sffnetwork.su"

void Multiplayer::connect(const char* name) {
    printf("name %s\n", name);
    m_name = name;

    m_state = MultiplayerState::CONNECTING;

    client = enet_host_create(nullptr, 1, LAST_CHANNEL, 0, 0);
    if (!client) {
        printf("client null\n");
        exit(1);
    }

    ENetAddress address;
    enet_address_set_host(&address, SERVER_ADDRESS);
    address.port = 7777;

    peer = enet_host_connect(client, &address, LAST_CHANNEL, 0);
    if (peer == nullptr) {
        printf("peer null\n");
        enet_host_destroy(client);
        exit(1);
    }

    ENetEvent event;
    auto res = enet_host_service(client, &event, 5000);

    if (res <= 0 || event.type != ENET_EVENT_TYPE_CONNECT) {
        enet_peer_reset(peer);
        printf("Failed to connect to server!\n");
        exit(1);
    }

    auto packet_size = 1 + 2 + strlen(name);
    auto login_packet = new char[packet_size];
    login_packet[0] = Header::IDENTIFICATION;
    *(uint16_t*)(login_packet + 1) = strlen(name);
    memcpy(login_packet + 3, name, strlen(name));

    if (sendPacket(login_packet, packet_size)) {
        printf("trying to reg!!\n");
        m_state = MultiplayerState::LOGGING_IN;
    }
}

int Multiplayer::sendPacket(char* data, int size, Channel channel, bool reliable) {
    auto enetPacket = enet_packet_create(data, size, reliable ? ENET_PACKET_FLAG_RELIABLE : ENET_PACKET_FLAG_UNRELIABLE_FRAGMENT);

    return enet_peer_send(peer, channel, enetPacket) == 0;
}

void Multiplayer::update(float dt) {
    ENetEvent event;
    while (enet_host_service(client, &event, 0) > 0) {
        switch (event.type) {
        case ENET_EVENT_TYPE_RECEIVE: {
            // printf("packet received\n");

            auto bytes = event.packet->data;

            // for (int i = 0; i < event.packet->dataLength; i++) {
            //     printf("%02X ", bytes[i]);
            // }
            // printf("\n");

            switch (bytes[0]) {
            case LOAD_PLAYER: { // all players get this when a new player connects
                bytes++;

                uint16_t nameLen = *(uint16_t*)bytes;
                bytes += 2;

                auto name = new char[nameLen + 1];
                memcpy(name, bytes, nameLen);
                bytes += nameLen;
                name[nameLen] = 0;

                uint32_t playerID = *(uint32_t*)bytes;
                bytes += 4;
                float serverTime = *(float*)bytes;

                printf("- load player name %s id %i server time %f\n", name, playerID, serverTime);

                Game::get().chatMessages.push_back({"Player " + std::string(name) + " has joined.", (float)GetTime()});

                if (m_name == name) {
                    printf("- its me!\n");
                    m_id = playerID;
                    m_state = MultiplayerState::PLAYING;
                    Game::get().serverTime = serverTime;

                    char packet = Header::LOAD_PLAYERS;

                    sendPacket(&packet, 1);
                } else {
                    // std::string texture = "assets/";
                    // std::string nicknamee = name;
                    // std::transform(nicknamee.begin(), nicknamee.end(), nicknamee.begin(), ::tolower);
                    // texture.append(nicknamee).append(".png");

                    auto p = Player(skinFromName(name), name);      
                    p.pos.y = -400;
                    Game::get().otherPlayers[playerID] = p;
                }

                break;
            }

            case LOAD_PLAYERS: { // get list of all players on server with their id,pos,name
                printf("- load players packet size %i\n", event.packet->dataLength);

                bytes++;

                auto num = *bytes;
                bytes++;

                for (int i = 0; i < num; i++) {
                    auto id = *(uint32_t*)bytes;
                    bytes += 4;
                    auto x = *(float*)bytes;
                    bytes += 4;
                    auto y = *(float*)bytes;
                    bytes += 4;

                    auto nameLen = *(uint16_t*)bytes;
                    bytes += 2;

                    auto name = new char[nameLen + 1];
                    name[nameLen] = 0;
                    memcpy(name, bytes, nameLen);
                    bytes += nameLen;

                    printf("- - player: x %f y %f name %s id %i\n", x, y, name, id);
                    // std::string texture = "assets/";
                    // std::string nicknamee = name;
                    // std::transform(nicknamee.begin(), nicknamee.end(), nicknamee.begin(), ::tolower);
                    // texture.append(nicknamee).append(".png");

                    auto p = Player(skinFromName(name), name);
                    // auto p = Player(texture.c_str(), name);
                    p.pos = {x, y};
                    Game::get().otherPlayers[id] = p;
                }

                break;
            }

            case PLAYER: { // pos of all players
                bytes++;

                auto num = *bytes;
                bytes++;

                for (int i = 0; i < num; i++) {
                    auto id = *(uint32_t*)bytes;
                    bytes += 4;
                    auto x = *(float*)bytes;
                    bytes += 4;
                    auto y = *(float*)bytes;
                    bytes += 4;

                    if (id == peer->connectID) {
                        continue;
                    }

                    if (Game::get().otherPlayers.contains(id)) {
                        auto& p = Game::get().otherPlayers[id];
                        // Game::get().otherPlayers[id].pos = {x, y};
                        auto delta_x = x - p.pos.x;
                        p.pos = {x, y};
                        p.vel.x = delta_x;
                        // p.walkRight = delta_x > 0;
                        if (delta_x > 0) {
                            p.walkRight = true;
                        } else if (delta_x < 0) {
                            p.walkRight = false;
                        }
                    }
                }

                break;
            }

            case MESSAGE: {
                bytes++;

                auto len = *(uint16_t*)bytes;
                bytes += 2;

                auto msg = new char[len + 1];
                msg[len] = 0;

                memcpy(msg, bytes, len);

                Game::get().chatMessages.push_back({msg, (float)GetTime()});

                delete[] msg;

                break;
            }

            default: {
                printf("- unk packet %i\n", bytes[0]);
                break;
            }
            }

            break;
        }

        case ENET_EVENT_TYPE_DISCONNECT: {
            printf("Connection closed.\n");
            break;
        }

        default: break;
        }
    }

    m_updateTime += dt;

    const auto POS_TIME = 1 / 30.f;
    if (m_updateTime > POS_TIME) {
        // printf("sending pos\n");
        m_updateTime -= POS_TIME;

        auto data = new char[1 + 4 + 4];

        data[0] = Header::PLAYER;
        *(float*)(data + 1) = Game::get().player.pos.x;
        *(float*)(data + 1 + 4) = Game::get().player.pos.y;

        sendPacket(data, 1 + 4 + 4);

        delete[] data;
    }
}