PHP: Form with smarty + captcha

Form composition with smarty + captcha

/*
    Usage: 
    $ff=array(
        array('text', 'field_name', 'label', array('class'=>'area'), array('postlabel'=>'ddd', 'validate'=>'empty')),
        array('separator', 'td_class', 'text here'),
        array('options', 'field_name2', 'label', array('options'=>array(1=>2)), array('postlabel'=>'ddd', 'check'=>'empty')),
        array('submit', '', '', array('value'=>'Sign up')),
        array('hidden',    'hid', '', array('value'=>'blah'))
    );
    sf_init($ff);
    
    $smarty->assign(array('f2'=>$ff, 'in'=>$_REQUEST));
    $sm->register_function('smarty_form', 'smarty_form');
    {smarty_form fields=$f2 in=$in table_attr="class=tabt cellpadding=0 cellspacing=0" form_attr="method=post" colspan_class="separator"}

*/

function sf_init(&$ff) {
    $ft=array('type', 'name', 'label', 'fp', 'gp'); // make readable array
    foreach ($ff as $fd) {
        $fdh=array(); foreach ($ft as $i=>$t) {if (isset($fd[$i])) $fdh[$t]=$fd[$i];}
        $f2[]=$fdh;
    }
    $ff=$f2;
}
function iname($f2, $fd) {
    foreach ($f2 as $i=>$f) {if ($f['name']==$fd) $fi=$i;}
    return (isset($fi) ? $fi : -1);
}
function vfields($f2) {
    $fr=array();
    foreach ($f2 as $f) {
        if (!in_array($f['type'], array('separator', 'submit')) && $f['name']!='captcha') $fr[]=$f['name']; 
    }
    return $fr;
}

function smarty_form($p, &$smarty) {
    $hidden=array();
    foreach ($p['fields'] as $i=>$_fd) {$fd=&$p['fields'][$i];
        // start values    
        $fd['fp']['name']=$fd['name']; // for form tags
        $fd['fp']['type']=$fd['type'];
        if (isset($p['in'][$fd['name']])) { // in-value
            $par=(in_array($fd['type'], array('options', 'radios', 'checkboxes')) ? 'selected' : 'value');
            $fd['fp'][$par]=$p['in'][$fd['name']];
        }
        // generate fields
        if (in_array($fd['type'], array('options', 'radios', 'checkboxes'))) {
            require_once(SMARTY_DIR."plugins/function.html_$fd[type].php");
            if (isset($p['in'][$fd['name']])) $fd['fp']['selected']=$p['in'][$fd['name']];
            $fields_t[$fd['name']]=call_user_func("smarty_function_html_$fd[type]", $fd['fp'], $smarty);
        } elseif (!in_array($fd['type'], array('separator', 'hidden'))) {
            $fields_t[$fd['name']]=_field_gen($fd['fp'], $fd['type']);
        }
        // data for table, hidden fields
        if ($fd['type']=='hidden') $hidden[]=_field_gen($fd['fp'], $fd['type']);
        elseif ($fd['type']=='separator') $data[][]=$fd['label'];
        else $data[]=array(
                $fd['label'].(isset($fd['gp']['check']) ? ' *' : ''), 
                $fields_t[$fd['name']].(isset($fd['gp']['plabel']) ? $fd['gp']['plabel'] : '') 
            );
    }
    
    $js=_jstext($p['fields']); // javascript-check
    return $js.'<form '.$p['form_attr'].($js ? ' onsubmit="return validate_form(this)"' : '').'>'.
        "\n".implode("\n", $hidden)."\n"._tablefm($data, &$p).'</form>';
}
function _tablefm($data, $p) {
    $res[]='<table '.$p['table_attr'].'>';
    $cols=0; foreach ($data as $line) {$c=count($line); if ($c>$cols) $cols=$c;}
    foreach ($data as $line) {
        $res[]='<tr>';
        if (count($line)==1) $res[]="<td class=\"$p[colspan_class]\" colspan=$cols>$line[0]</td>";
        else {foreach ($line as $y=>$v) $res[]="<td>$v</td>";}
        $res[]='</tr>';
    }
    $res[]='</table>';
    return implode("\n", $res);
}
function _jstext($fields_h) {
    foreach ($fields_h as $fd) {
        if (!isset($fd['gp']['check'])) continue;
        $rs['name'][]=$fd['name'];
        $rs['label'][]=$fd['label'];
        $rs['check'][]=$fd['gp']['check'];
    }
    if (!$rs) return '';    
    return '
<script>
v_names = new Array("'.implode('", "', $rs['name']).'");
v_checks = new Array("'.implode('", "', $rs['check']).'");
v_labels = new Array("'.implode('", "', $rs['label']).'");

function validate_form(obj) {
    errors=""; 
    for (i=0; i<obj.elements.length; i++) {
        for (y=0; y<v_names.length; y++) {
            if (obj.elements[i].name==v_names[y]) errors+=_validate(v_checks[y], obj.elements[i], v_labels[y]);
        }
    }
    if (errors) {alert(errors); return false;}
    else return true; 
}
function _validate(type, obj, label) {
    res="";    
    if (type=="email") {
        if (obj.value.indexOf(".")>2 && obj.value.indexOf("@") > 0) res="";
        else res="E-mail address is not valid\n";
    } else if (type=="empty") {
        if (obj.value=="" || obj.value==null) res="Field \""+label+"\" is empty\n";
    }
    return res;
}
</script>
';
}
function _field_gen($params, $type='input') {
    if ($type=='textarea') {
        foreach ($params as $k=>$v) {if ($k!='value') $pp="$k=\"$v\"";}
        return '<textarea '.implode(' ', $pp).'>'.(isset($params['value']) ? $params['value'] : '').'</textarea>';
    } else {
        foreach ($params as $k=>$v) {$pp[]="$k=\"$v\"";}
        return '<input '.implode(' ', $pp).'>';
    }
}
    

/* 
    Usage:
    image.php: 
        $captcha=array(140, 34, 'britanic.ttf', 25, 0, 0, 0, array(255,255,255), array(0,0,50)); 
        captcha();
    form.php: 
        <form method="POST"><img src="img.php"><input type="text" name="captcha"><input type="submit"></form>
        if ($_POST && check_captcha()) echo "ok";
    
*/

function captcha() {
    global $captcha;
    list($box_w, $box_h, $font, $font_size, $font_angle, $margin_left, $margin_top, $color_bg, $color_text)=$captcha;
    $pass=''; $chm=rand(0,1);
    $ch=array(str_split('aeiouy'), str_split('bcdfjhgkmnprstvxz'));
    while (strlen($pass)<6) {$pass.=$ch[$chm][array_rand($ch[$chm])]; $chm=($chm ? 0:1);}
    session_start();
    $_SESSION['captcha'] = $pass;
    $image = ImageCreatetruecolor($box_w,$box_h); // create the image resource
    $color_bg = ImageColorAllocate($image, $color_bg[0], $color_bg[1], $color_bg[2]); // set colors
    $color_text = ImageColorAllocate($image, $color_text[0], $color_text[1], $color_text[2]);
    imagefill($image, 0, 0, $color_bg); // set background
    imagettftext($image, $font_size, $font_angle, $margin_left, $font_size + $margin_top, $color_text, $font, $pass); // set text
    header("Content-Type: image/jpg"); // or image/jpg
    imagejpeg($image); // created image
    imagedestroy($image);
}
function check_captcha() {
    session_start();
    if (isset($_SESSION['captcha']) && isset($_REQUEST['captcha']) && $_SESSION['captcha']==$_REQUEST['captcha']) {
        unset($_SESSION['captcha']);
        return 1;
    }
    return 0;
}