cloud-game/static/js/gameboy_controller.js

// menu screen
function showMenuScreen() {
    log("Clean up connection / frame");
    // clean up before / after menu
    try {
        inputChannel.close();
    } catch (err) {
        log(`> [Warning] input channel: ${err}`);
    }

    try {
        pc.close();
    } catch (err) {
        log(`> [Warning] peer connection: ${err}`);
    }

    try {
        conn.close();
    } catch (err) {
        log(`> [Warning] Websocket connection: ${err}`);
    }


    $("#loading-screen").hide();
    $("#menu-screen").hide();

    // show

    $("#loading-screen").show().delay(1000).fadeOut(400, () => {
        log("Loading menu screen");
        $("#menu-screen").fadeIn(400, () => {
            chooseGame(7);
            screenState = "menu";
        });
    });
}


// game menu
function chooseGame(idx) {
    if (idx < 0 || idx == gameIdx || idx >= GAME_LIST.length) return false;

    $("#menu-screen #box-art").fadeOut(400, function () {
        $(this).attr("src", `/static/img/boxarts/${GAME_LIST[idx].art}`);
        $(this).fadeIn(400, function () {
            $("#menu-screen #title p").html(GAME_LIST[idx].name);
        });
    });

    if (idx == 0) {
        $("#menu-screen .left").hide();
    } else {
        $("#menu-screen .left").show();
    }

    if (idx == GAME_LIST.length - 1) {
        $("#menu-screen .right").hide();
    } else {
        $("#menu-screen .right").show();
    }

    gameIdx = idx;
    log(`> [Pick] game ${gameIdx + 1}/${GAME_LIST.length} - ${GAME_LIST[gameIdx].name}`);
}

function setState(e, bo) {
    if (e.keyCode in KEY_MAP) {
        keyState[KEY_MAP[e.keyCode]] = bo;
        stateUnchange = false;
        unchangePacket = INPUT_STATE_PACKET;
    }
}

document.body.onkeyup = function (e) {
    if (screenState === "menu") {
        switch (KEY_MAP[e.keyCode]) {
            case "left":
                chooseGame(gameIdx - 1);
                break;

            case "right":
                chooseGame(gameIdx + 1);
                break;

            case "select":
                startGame();
        }
    } else if (screenState === "game") {
        setState(e, false);
    }

    // global reset
    if (KEY_MAP[e.keyCode] == "quit") {
        endInput();
        showMenuScreen();
    }

}

document.body.onkeydown = function (e) {
    if (screenState === "game")
        setState(e, true);
};


function sendInput() {
    // prepare key
    if (stateUnchange || unchangePacket > 0) {
        st = "";
        KEY_BIT.forEach(elem => {
            st += keyState[elem] ? 1 : 0;
        });
        ss = parseInt(st, 2);
        console.log(`Key state string: ${st} ==> ${ss}`);

        // send
        inputChannel.send(ss);

        stateUnchange = false;
        unchangePacket--;
    }
}


function startInput() {
    if (inputTimer == null) {
        inputTimer = setInterval(sendInput, 1000 / INPUT_FPS)
    }
}

function endInput() {
    clearInterval(inputTimer);
    inputTimer = null;
}