nw/ttt.php

## ttt.php
<?php

$players = ["X", "O"];

$current_player_idx = getPlayerIdx();
$player = $players[$current_player_idx];
$next_player_idx = getNextPlayerIdx($current_player_idx);

$board = [
    [null, null, null],
    [null, null, null],
    [null, null, null]
];


if(isset($_POST['select'])){
    $parts = explode(',', $_POST['select']);
    $board[$parts[0]][$parts[1]] = $player; // sets piece

    if(isset($_POST['board'])) {
        forEach ($_POST['board'] as $rowidx => $row) {
            forEach ($row as $colidx => $col) {
                $board[$rowidx][$colidx] = $col;
            }
        }

    }
}


function debug($val){
    $output = print_r($val, true);
    echo "<pre>". $output ."</pre>";
}


function getCell($row, $col){

    global $board;

    $val = $board[$row][$col];

    if(is_null($val)){
        return "<input type='submit' value='$row,$col' name='select' />";
    } else {
        return "<h1>$val</h1><input type='hidden' name='board[$row][$col]' value='$val' />";
    }
}


function getPlayerIdx(){

    $val = 1;

    if(isset($_POST['player'])){
        $val = intval($_POST['player']);
    }

    return $val;
}

function getNextPlayerIdx($idx){
    global $players;

    $val = $idx;
    $val++;
    if($val >= count($players)) $val = 0;
    return $val;

}


?>

<html>
<head>
    <title>Tic Tac Toe</title>
</head>
<body>
    <form method="POST">
        <input type="hidden" value="<?= $next_player_idx; ?>"  name="player" />
        <table border="1", cellspacing="0" cellpadding="25">
            <tr>
                <td><?= getCell(0,0); ?></td>
                <td><?= getCell(0,1); ?></td>
                <td><?= getCell(0,2); ?></td>
            </tr>
            <tr>
                <td><?= getCell(1,0); ?></td>
                <td><?= getCell(1,1); ?></td>
                <td><?= getCell(1,2); ?></td>
            </tr>
            <tr>
                <td><?= getCell(2,0); ?></td>
                <td><?= getCell(2,1); ?></td>
                <td><?= getCell(2,2); ?></td>
            </tr>
        </table>
    </form>
    <?= debug($board); ?>
</body>
</html>
	<?php

	$players = ["X", "O"];

	$current_player_idx = getPlayerIdx();
	$player = $players[$current_player_idx];
	$next_player_idx = getNextPlayerIdx($current_player_idx);

	$board = [
	[null, null, null],
	[null, null, null],
	[null, null, null]
	];


	if(isset($_POST['select'])){
	$parts = explode(',', $_POST['select']);
	$board[$parts[0]][$parts[1]] = $player; // sets piece

	if(isset($_POST['board'])) {
	forEach ($_POST['board'] as $rowidx => $row) {
	forEach ($row as $colidx => $col) {
	$board[$rowidx][$colidx] = $col;
	}
	}

	}
	}


	function debug($val){
	$output = print_r($val, true);
	echo "<pre>". $output ."</pre>";
	}


	function getCell($row, $col){

	global $board;

	$val = $board[$row][$col];

	if(is_null($val)){
	return "<input type='submit' value='$row,$col' name='select' />";
	} else {
	return "<h1>$val</h1><input type='hidden' name='board[$row][$col]' value='$val' />";
	}
	}


	function getPlayerIdx(){

	$val = 1;

	if(isset($_POST['player'])){
	$val = intval($_POST['player']);
	}

	return $val;
	}

	function getNextPlayerIdx($idx){
	global $players;

	$val = $idx;
	$val++;
	if($val >= count($players)) $val = 0;
	return $val;

	}


	?>

	<html>
	<head>
	<title>Tic Tac Toe</title>
	</head>
	<body>
	<form method="POST">
	<input type="hidden" value="<?= $next_player_idx; ?>" name="player" />
	<table border="1", cellspacing="0" cellpadding="25">
	<tr>
	<td><?= getCell(0,0); ?></td>
	<td><?= getCell(0,1); ?></td>
	<td><?= getCell(0,2); ?></td>
	</tr>
	<tr>
	<td><?= getCell(1,0); ?></td>
	<td><?= getCell(1,1); ?></td>
	<td><?= getCell(1,2); ?></td>
	</tr>
	<tr>
	<td><?= getCell(2,0); ?></td>
	<td><?= getCell(2,1); ?></td>
	<td><?= getCell(2,2); ?></td>
	</tr>
	</table>
	</form>
	<?= debug($board); ?>
	</body>
	</html>