Rohan Prabhu

/*
 * KWin Pong
 * -------------------------------
 *         [rohan@rohanprabhu.com]
 *         (c) Rohan Prabhu
 * ---- R46F --- 37 --- R46F -----
 */

function viewportHeight() {
    return (workspace.dimensions().h)/(workspace.desktopGridSize().h);
}

function viewportWidth() {
    return (workspace.dimensions().w)/(workspace.desktopGridSize().w);
}

function findCenter(canvas_size, rect_size) {
    var ret = new Object();
    ret.x = (canvas_size.w - rect_size.w)/2;
    ret.y = (canvas_size.h - rect_size.h)/2;
    return ret;
}

var playerHandle;
var ballHandle;
var computerHandle;

var p_score = 0;
var c_score = 0;

// Set this value a little higher if the game looks sluggish
// all a little lower if the game looks choppy
var timer_res = 30;

var stumble = 0;

var ft_iter = 0;

var firstTimer = new QTimer();
var pollTimer = new QTimer();

function startGame() {
    if(ft_iter == 0) {
        firstTimer.timeout.connect(startGame);
        firstTimer.start(1000);
    }

    // A tribute to Warcraft
    if(ft_iter < 3) {
        print("Game starting in " + (3 - ft_iter) + " seconds ...");
        ft_iter++;
    }

    if(ft_iter == 3) {
        firstTimer.timeout.disconnect(startGame);
        print("GAME STARTING");

        pollTimer.timeout.connect(moveBall);
        pollTimer.timeout.connect(computerJi);
        pollTimer.start(timer_res);
    }
}

function computerJi() {
    // For those who don't understand why this function
    // is names so, try a hint
    // 1. Be from India
    // 2. A famous show hosted by Amitabh Bachchan

    // Sample algorithm taken from: http://tinyurl.com/396leup
    // Thanks to [SoulRed12]. Used under Fair Use qualification

    var cLoc = computerHandle.pos();
    var loc = ballHandle.pos();

    var dist = Math.abs(loc.y - cLoc.y);

    if((loc.y + (75/2)) > cLoc.y && dist > computerHandle.vel) {
        computerHandle.move(cLoc.x, Math.min(cLoc.y + computerHandle.vel*(timer_res/1000), viewportHeight() - 400));
    } else if((loc.y + (75/2)) < cLoc.y && dist > computerHandle.vel) {
        computerHandle.move(cLoc.x, Math.min(cLoc.y - computerHandle.vel*(timer_res/1000), viewportHeight() - 400));
    }
}

function checkCollision() {
    var loc = ballHandle.pos();
    var pLoc = playerHandle.pos();
    var cLoc = computerHandle.pos();

    // No code here for upper and lower bat
    // boundaries. Not yet atleast

    if((loc.x <= (pLoc.x + 100)) && (loc.y > (pLoc.y - 75)) && (loc.y < (pLoc.y + 400))) {
        return { col: 1, type: 0, bat: 1};
    } else if((loc.x >= (cLoc.x - 75)) && (loc.y > (cLoc.y - 75)) && (loc.y < (cLoc.y + 400))) {
        return { col: 1, type: 2, bat: 1};
    }

    if(loc.x > (viewportWidth() - 75)) {
        return { col: 1, type: 2, bat: -1};
    } else if(loc.x <= 0) {
        return { col: 1, type: 0, bat: -1};
    } else if(loc.y > (viewportHeight() - 75)) {
        return { col: 1, type: 3, bat: -1};
    } else if(loc.y <= 0) {
        return { col: 1, type: 1, bat: -1};
    } else {
        return { col: 0, type: -1, bat: -1};
    }
}

function reset_pong() {
    playerHandle.resize(100, 400);
    playerHandle.move(0, 0);
    computerHandle.resize(100, 400);
    computerHandle.move(viewportWidth() - 100, 0);
    ballHandle.resize(75, 75);
    ballHandle.move(findCenter({w: viewportWidth(), h: viewportHeight()}, {w: 150, h: 150}));
    ballHandle.dx = -1;
    ballHandle.dy = 1;
}

function resume() {
    pollTimer.start(timer_res);
}

function score(who) {
    if(who == 0) {
        p_score++;
    } else if(who == 1) {
        c_score++;
    }

    pollTimer.stop();
    reset_pong();

    var message = "";

    if(who == 0) {
        message += "######################\n";
        message += "### PLAYER1 SCORED ###\n";
        message += "######################\n";
    } else {
        message += "#######################\n";
        message += "### COMPUTER SCORED ###\n";
        message += "#######################\n";
    }

    message += "SCORES [PL1 : " + p_score + " | CMP: " + c_score + " ... atari PONG";
    print(message);

    firstTimer.timeout.connect(resume);
    firstTimer.start(1000);
}

function moveBall() {
    var location = ballHandle.pos();
    var _x = (ballHandle.dx)*(ballHandle.vel)*(timer_res/1000);
    var _y = (ballHandle.dy)*(ballHandle.vel)*(timer_res/1000);

    ballHandle.move(location.x + _x, location.y + _y);
    var coll = checkCollision();

    if(coll.col == 1) {
        if(coll.type == 0) {
            if(coll.bat == -1) {
                score(1);
            }

            ballHandle.dx = 1;
        } else if(coll.type == 1) {
            ballHandle.dy = 1;
        } else if(coll.type == 2) {
            if(coll.bat == -1) {
                score(0);
            }
            ballHandle.dx = -1;
        } else if(coll.type == 3) {
            ballHandle.dy = -1;
        }
    }
}

function constrainPlayer() {
    var location = playerHandle.pos();
    playerHandle.resize(100, 400);
    playerHandle.move(0, Math.min(location.y, viewportHeight() - 400));
}

function getPlayerFromFocus(client) {
    if(stumble == 0) {
        stumble = 1;
        return;
    }

    playerHandle = client;
    playerHandle.resize(100, 400);
    playerHandle.move(0, 0);
    playerHandle.clientMoved.connect(constrainPlayer);

    print("<-----------------------------\\");
    print(" > Player will be controlling [" + playerHandle.caption() + "]");
    print("<-----------------------------/"); print("");
    playerHandle.setCaption("PLAYER1");
    workspace.clientActivated.disconnect(getPlayerFromFocus);
    selectBall();
}

function getBallFromFocus(client) {
    ballHandle = client;
    ballHandle.resize(75, 75);
    ballHandle.move(findCenter({w: viewportWidth(), h: viewportHeight()}, {w: 150, h: 150}));

    // Initial kickoff direction
    ballHandle.dx = -1;
    ballHandle.dy = -1;
    ballHandle.vel = 250; // speed in pixels per second

    print("<----------------------------\\");
    print("The ball being used would be [" + ballHandle.caption() + "]");
    print("<----------------------------/"); print("");

    ballHandle.setCaption("BALL");

    workspace.clientActivated.disconnect(getBallFromFocus);
    selectComputerHandle();
}

function getComputerFromFocus(client) {
    computerHandle = client;
    computerHandle.resize(100, 400);
    computerHandle.move(viewportWidth() - 100, 0);
    computerHandle.vel = 160;

    print("<-------------------------------\\");
    print(" > Computer will be controlling [" + computerHandle.caption() + "]");
    print("<-------------------------------/"); print("");
    computerHandle.setCaption("COMPUTER");
    workspace.clientActivated.disconnect(getComputerFromFocus);
    selectScoreBoard();
}

function getScoreBoardFromFocus(client) {
    sbHandle = client;
    sbHandle.resize(400, 150);
    sbHandle.move(findCenter({w: viewportWidth(), h: viewportHeight()}, {w: 400, h: 150}).x, viewportHeight() - 150);
    startGame();
}

function selectScoreBoard() {
    print("Please focus the client which houses the terminal for the current output");
    workspace.clientActivated.connect(getScoreBoardFromFocus);
}

function selectComputerHandle() {
    print("Please focus the client you wish to use as the computer handle");
    workspace.clientActivated.connect(getComputerFromFocus);
}

function selectBall() {
    print("Please focus the client you wish to use as the ball");
    workspace.clientActivated.connect(getBallFromFocus);
}

function selectPlayerHandle() {
    print("Please focus the client you wish to use as a player handle");
    workspace.clientActivated.connect(getPlayerFromFocus);
}

if(startPong == 1) {
    print("#################");
    print("### KWIN PONG ###");
    print("#################");
    print("1 Player");
    selectPlayerHandle();
}