scufpong/src/game/MultiPlayer.c

#include <asm-generic/errno.h>
#include <stdio.h>
#include <sys/socket.h>
#include <netdb.h>
#include <errno.h>
#include <string.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <fcntl.h>

#include "scufeng/log.h"

#include "networking.h"
#include "MultiPlayer.h"
#include "game.h"
#include "game_common.h"
#include "GameState_net.h"

static bool handle_game_state_msg(MultiPlayer *const mp) {
    GameStateMsg msg;
    if (!recv_msg(mp->conn_s, NET_MSG_GAME_STATE, (uint8_t *) &msg)) {
        return false;
    }
    GameStateMsg_to_GameState(&msg, &mp->state);
    return true;
}

bool MultiPlayer_alloc(
    MultiPlayer *const mp,
    const unsigned int screen_w,
    const unsigned int screen_h,
    const char *server_host,
    const uint16_t server_port
) {
    struct protoent *proto = getprotobyname("tcp");
    mp->sock = socket(AF_INET, SOCK_STREAM, proto->p_proto);
    if (mp->sock == -1) {
        SE_LOG_FATALF("socket failed: %d %s", errno, strerror(errno));
    }

    struct in_addr server_addr;
    int res = inet_aton(server_host, &server_addr);
    if (res == 0) {
        close(mp->sock);
        SE_LOG_FATAL("inet_aton failed");
    }

    struct sockaddr_in server_sockaddr = {
        .sin_family = AF_INET,
        .sin_addr = server_addr,
        .sin_port = htons(server_port)
    };

    res = connect(
        mp->sock,
        (struct sockaddr *) &server_sockaddr,
        sizeof(server_sockaddr)
    );
    if (res == -1) {
        close(mp->sock);
        SE_LOG_ERRORF("connect failed: %d %s", errno, strerror(errno));
        return false;
    }

    SE_LOG("Connected to server");

    mp->conn_s = fdopen(mp->sock, "r+");
    if (mp->conn_s == nullptr) {
        close(mp->sock);
        SE_LOG_ERRORF("fdopen failed: (%d) %s", errno, strerror(errno));
        return false;
    }

    NetMsgType msg_type;
    if (recv_msg_type(mp->conn_s, &msg_type) == ECONNRESET) {
        fclose(mp->conn_s);
        close(mp->sock);
        SE_LOG_ERROR("Connection reset");
        return false;
    }
    if (msg_type != NET_MSG_IS_PLAYER_1) {
        fclose(mp->conn_s);
        close(mp->sock);
        SE_LOG_ERRORF("Did not get IS_PLAYER_1 msg, got: %u", msg_type);
        return false;
    }
    IsPlayer1Msg p1_msg = { 0 };
    if (!recv_msg(mp->conn_s, NET_MSG_IS_PLAYER_1, (uint8_t *) &p1_msg)) {
        fclose(mp->conn_s);
        close(mp->sock);
        SE_LOG_ERROR("Connection reset");
        return false;
    }
    mp->is_player_1 = (bool) p1_msg.player1;
    if (mp->is_player_1) {
        SE_LOG("I am player 1");
    } else {
        SE_LOG("I am player 2");
    }

    SE_LOG("Waiting for game start");

    mp->state = GameState_new(game_default_params, false);

    if (recv_msg_type(mp->conn_s, &msg_type) == ECONNRESET) {
        fclose(mp->conn_s);
        close(mp->sock);
        SE_LOG_ERROR("Connection reset");
        return false;
    }
    if (msg_type != NET_MSG_GAME_STATE) {
        fclose(mp->conn_s);
        close(mp->sock);
        SE_LOG_FATALF("[MultiPlayer_alloc] Did not get GAME_STATE msg, got: %u", msg_type);
    }
    if (!handle_game_state_msg(mp)) {
        fclose(mp->conn_s);
        close(mp->sock);
        SE_LOG_ERROR("Connection reset");
        return false;
    }

    if (recv_msg_type(mp->conn_s, &msg_type) == ECONNRESET) {
        fclose(mp->conn_s);
        close(mp->sock);
        SE_LOG_ERROR("Connection reset");
        return false;
    }
    if (msg_type != NET_MSG_GAME_START) {
        fclose(mp->conn_s);
        close(mp->sock);
        SE_LOG_FATALF("[MultiPlayer_alloc] Did not get GAME_START msg, got: %u", msg_type);
    }

    if (!send_msg(mp->conn_s, NET_MSG_GAME_START, nullptr)) {
        fclose(mp->conn_s);
        close(mp->sock);
        SE_LOG_ERROR("Connection reset");
        return false;
    }

    if (fcntl(mp->sock, F_SETFL, O_NONBLOCK) != 0) {
        fclose(mp->conn_s);
        close(mp->sock);
        SE_LOG_ERRORF("fcntl failed on mp->sock: (%d) %s", errno, strerror(errno));
        return false;
    }

    SE_LOG("Game started");

    mp->screen_w = screen_w;
    mp->screen_h = screen_h;
    mp->shapes = GameShapes_alloc(screen_w, screen_h, game_default_params);

    return mp;
}

void MultiPlayer_free(MultiPlayer *const mp) {
    fclose(mp->conn_s);
    mp->conn_s = nullptr;
    // close(mp->conn);
    // mp->conn = 0;
    close(mp->sock);
    mp->sock = 0;

    GameShapes_free(&mp->shapes);
}

static void handle_paddle_pos_msg(MultiPlayer *const mp) {
    PaddleUpdateMsg msg;
    recv_msg(mp->conn_s, NET_MSG_PADDLE_POS, (uint8_t *) &msg);
    mp->state.paddle_l.pos[1] = msg.l_pos_y;
    mp->state.paddle_l.dirv[1] = msg.l_dirv_y;
    mp->state.paddle_r.pos[1] = msg.r_pos_y;
    mp->state.paddle_r.dirv[1] = msg.r_dirv_y;
}

static void handle_ball_update_msg(MultiPlayer *const mp) {
    BallUpdateMsg msg;
    recv_msg(mp->conn_s, NET_MSG_BALL_UPDATE, (uint8_t *) &msg);
    mp->state.ball.pos[0] = msg.ball_pos_x;
    mp->state.ball.pos[1] = msg.ball_pos_y;
    mp->state.ball.dirv[0] = msg.ball_dirv_x;
    mp->state.ball.dirv[1] = msg.ball_dirv_y;
}

static void handle_score_update_msg(MultiPlayer *const mp) {
    ScoreUpdateMsg msg;
    recv_msg(mp->conn_s, NET_MSG_SCORE_UPDATE, (uint8_t *) &msg);
    mp->state.score_l = msg.l_score;
    mp->state.score_r = msg.r_score;
    SE_LOGF("score_l: %d score_r: %d", mp->state.score_l, mp->state.score_r);
}

static void handle_input(
    const MultiPlayer *const mp,
    bool *dir_changed,
    SEDirection *new_dir,
    bool *quit
) {
    if (se_get_key(SE_KEY_ESCAPE) == SE_KEY_ACTION_PRESS) {
        *quit = true;
        return;
    }

    *new_dir = SE_NONE;
    *dir_changed = false;
    const SEDirection current_dir = GameState_paddle_l_dir_get(&mp->state);
    if (se_get_key(SE_KEY_W) == SE_KEY_ACTION_PRESS) {
        if (current_dir != SE_UP) {
            *new_dir = SE_UP;
            *dir_changed = true;
        }
    } else if (se_get_key(SE_KEY_S) == SE_KEY_ACTION_PRESS) {
        if (current_dir != SE_DOWN) {
            *new_dir = SE_DOWN;
            *dir_changed = true;
        }
    } else if (current_dir != SE_NONE) {
        *new_dir = SE_NONE;
        *dir_changed = true;
    }
}

Screen MultiPlayer_tick(MultiPlayer *const mp, const double delta) {
    NetMsgType msg_type;
    while (true) {
        const int res = recv_msg_type(mp->conn_s, &msg_type);
        if (res == 0) {
            switch (msg_type) {
            case NET_MSG_PADDLE_CHANGE_DIR:
                break;
            case NET_MSG_PADDLE_POS:
                handle_paddle_pos_msg(mp);
                break;
            case NET_MSG_GAME_STATE:
                handle_game_state_msg(mp);
                break;
            case NET_MSG_IS_PLAYER_1:
            case NET_MSG_GAME_START:
                break;
            case NET_MSG_BALL_UPDATE:
                handle_ball_update_msg(mp);
                break;
            case NET_MSG_SCORE_UPDATE:
                handle_score_update_msg(mp);
                break;
            }
            break;
        } else if (res == ECONNRESET) {
            SE_LOG_ERROR("Connection reset");
            return PONG_MAIN_MENU;
        } else if (res == EWOULDBLOCK) {
            break;
        } else {
            SE_LOG_FATALF("[MultiPlayer_tick] Unhandled return value: %d", res);
        }

        // SE_LOGF("Got message: %s", NetMsgType_to_str(msg_type));
    }

    bool dir_changed = false;
    SEDirection new_dir;
    bool quit = false;
    handle_input(mp, &dir_changed, &new_dir, &quit);
    if (quit) {
        return PONG_MAIN_MENU;
    }

    if (dir_changed) {
        GameState_paddle_l_change_dir(&mp->state, new_dir);
        const PaddleChangeDirMsg msg = {
            .dir = (uint8_t) new_dir
        };

        if (!send_msg(mp->conn_s, NET_MSG_PADDLE_CHANGE_DIR, (uint8_t *) &msg)) {
            SE_LOG_ERROR("Connection reset");
            return PONG_MAIN_MENU;
        }
    }

    GameState_update(&mp->state, delta);
    GameShapes_update(&mp->shapes, &mp->state, mp->screen_w, mp->screen_h);
    GameShapes_render(&mp->shapes, &mp->state, mp->screen_w, mp->screen_h);

    return PONG_MULTIPLAYER;
}