<?


//http://www.foreveramoreweddings.com/index.php?indi_sfondo=1&crgb1_h=0&crgb1_s=0&crgb1_l=0&crgb1_a=0.6

//crea un immagine png 1x1 in base ai parametri colore e alpha
//da fare: abilitare la cache

//cache
$timestamp = time() + (3600*24) * 7;
header("Expires: " . gmdate("D, d M Y H:i:s",$timestamp) . " GMT");
header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
header("Content-type: image/png");

if($_GET['indi_sfondo'] == 1) {
	
	
	//controllo se c'e' il parametro color_rgb e sovrascrivo tutto
	if(
	   is_numeric($_GET['crgb1_h']) and 
	   is_numeric($_GET['crgb1_s']) and 
	   is_numeric($_GET['crgb1_l']) and 
	   is_numeric($_GET['crgb1_a'])
	)  {

		$componenti['0']	=	$_GET['crgb1_h'];	
		$componenti['1']	=	$_GET['crgb1_s'];	
		$componenti['2']	=	$_GET['crgb1_l'];	
		$componenti['3']	=	$_GET['crgb1_a'];	
	
	} else die();


	
		$alfa = abs(127-floor($componenti['3'] * 127)-2);
		if($componenti['3'] == 0)  $alfa = 127;
	
	if(is_array($componenti)) {
		$im     = imagecreatetruecolor(1, 1);
		
		imagealphablending( $im, false );
		imagesavealpha( $im, true );
		
		imagefilledrectangle($im, 0, 0, 1, 1, imagecolorallocatealpha ($im,$componenti['0'],$componenti['1'],$componenti['2'],$alfa));
	
		//immagine
		//header("Content-type: image/png");
		imagepng($im);
		imagedestroy($im);
	}

} 


//con gradiente
if($_GET['indi_sfondo'] == 2) {
	
	if(
	   is_numeric($_GET['crgb1_h']) and 
	   is_numeric($_GET['crgb1_s']) and 
	   is_numeric($_GET['crgb1_l']) and 
	   is_numeric($_GET['crgb1_a'])	and
	   is_numeric($_GET['crgb2_h']) and 
	   is_numeric($_GET['crgb2_s']) and 
	   is_numeric($_GET['crgb2_l']) and 
	   is_numeric($_GET['crgb2_a'])
	)  {

		$componenti1['0']	=	$_GET['crgb1_h'];	
		$componenti1['1']	=	$_GET['crgb1_s'];	
		$componenti1['2']	=	$_GET['crgb1_l'];	
		$componenti1['3']	=	$_GET['crgb1_a'];	
	
		$componenti2['0']	=	$_GET['crgb2_h'];	
		$componenti2['1']	=	$_GET['crgb2_s'];	
		$componenti2['2']	=	$_GET['crgb2_l'];	
		$componenti2['3']	=	$_GET['crgb2_a'];	
	
	} else die;
	
	
		
		$colore1 = rgb2html($componenti1[0],$componenti1[1],$componenti1[2]);
		$colore2 = rgb2html($componenti2[0],$componenti2[1],$componenti2[2]);
	
		//normalizzo alpha
		//$componenti1['3'] = $componenti1['3'] + $componenti1['3'] * 0.01;
		$alfa = abs(127-floor($componenti1['3'] * 127)-2);
		if($componenti1['3'] == 0)  $alfa = 127;
		
		$image = new gd_gradient_fill($_GET['width'],$_GET['height'],$_GET['type'],$colore1,$colore2,$alfa);
} 





function html2rgb($color)
{
    if ($color[0] == '#')
        $color = substr($color, 1);

    if (strlen($color) == 6)
        list($r, $g, $b) = array($color[0].$color[1],
                                 $color[2].$color[3],
                                 $color[4].$color[5]);
    elseif (strlen($color) == 3)
        list($r, $g, $b) = array($color[0].$color[0], $color[1].$color[1], $color[2].$color[2]);
    else
        return false;

    $r = hexdec($r); $g = hexdec($g); $b = hexdec($b);

    return array($r, $g, $b);
}
class gd_gradient_fill {
    
    // Constructor. Creates, fills and returns an image
    function gd_gradient_fill($w,$h,$d,$s,$e,$alpha1) {
        $this->width = $w;
        $this->height = $h;
        $this->direction = $d;
        $this->startcolor = $s;
        $this->endcolor = $e;
        $this->alpha1 = $alpha1;

        // Attempt to create a blank image in true colors, or a new palette based image if this fails
        if($this->width and $this->height) {
				$this->image = imagecreatetruecolor($this->width,$this->height);
        
				imagealphablending($this->image, false );
				imagesavealpha($this->image, true );
				
				  // Fill it
       			 $this->fill($this->image,$this->direction,$this->startcolor,$this->endcolor);
        
       			 // Show it        
				 imagepng($this->image);
		} else {
			die();
		
		}
	
     
        
        // Return it
       // return $this->image;
    }
    
    
    // The main function that draws the gradient
    function fill($im,$direction,$start,$end) {
        
        switch($direction) {
            case 'horizontal':
                $line_numbers = imagesx($im);
                $line_width = imagesy($im);
                list($r1,$g1,$b1) = $this->hex2rgb($start);
                list($r2,$g2,$b2) = $this->hex2rgb($end);
                break;
            case 'vertical':
                $line_numbers = imagesy($im);
                $line_width = imagesx($im);
                list($r1,$g1,$b1) = $this->hex2rgb($start);
                list($r2,$g2,$b2) = $this->hex2rgb($end);
                break;
            case 'ellipse':
                $width = imagesx($im);
                $height = imagesy($im);
                $rh=$height>$width?1:$width/$height;
                $rw=$width>$height?1:$height/$width;
                $line_numbers = min($width,$height);
                $center_x = $width/2;
                $center_y = $height/2;
                list($r1,$g1,$b1) = $this->hex2rgb($end);
                list($r2,$g2,$b2) = $this->hex2rgb($start);
                imagefill($im, 0, 0, imagecolorallocatealpha( $im, $r1, $g1, $b1, $this->alpha1 ));
                break;
            case 'ellipse2':
                $width = imagesx($im);
                $height = imagesy($im);
                $rh=$height>$width?1:$width/$height;
                $rw=$width>$height?1:$height/$width;
                $line_numbers = sqrt(pow($width,2)+pow($height,2));
                $center_x = $width/2;
                $center_y = $height/2;
                list($r1,$g1,$b1) = $this->hex2rgb($end);
                list($r2,$g2,$b2) = $this->hex2rgb($start);
                break;
            case 'circle':
                $width = imagesx($im);
                $height = imagesy($im);
                $line_numbers = sqrt(pow($width,2)+pow($height,2));
                $center_x = $width/2;
                $center_y = $height/2;
                $rh = $rw = 1;
                list($r1,$g1,$b1) = $this->hex2rgb($end);
                list($r2,$g2,$b2) = $this->hex2rgb($start);
                break;
            case 'circle2':
                $width = imagesx($im);
                $height = imagesy($im);
                $line_numbers = min($width,$height);
                $center_x = $width/2;
                $center_y = $height/2;
                $rh = $rw = 1;
                list($r1,$g1,$b1) = $this->hex2rgb($end);
                list($r2,$g2,$b2) = $this->hex2rgb($start);
                imagefill($im, 0, 0, imagecolorallocatealpha( $im, $r1, $g1, $b1,$this->alpha1  ));
                break;
            case 'square':
            case 'rectangle':
                $width = imagesx($im);
                $height = imagesy($im);
                $line_numbers = max($width,$height)/2;
                list($r1,$g1,$b1) = $this->hex2rgb($end);
                list($r2,$g2,$b2) = $this->hex2rgb($start);
                break;
            case 'diamond':
                list($r1,$g1,$b1) = $this->hex2rgb($end);
                list($r2,$g2,$b2) = $this->hex2rgb($start);
                $width = imagesx($im);
                $height = imagesy($im);
                $rh=$height>$width?1:$width/$height;
                $rw=$width>$height?1:$height/$width;
                $line_numbers = min($width,$height);
                break;
            default:
        }
        
        for ( $i = 0; $i < $line_numbers; $i=$i+1+$this->step ) {
            // old values :
            $old_r=$r;
            $old_g=$g;
            $old_b=$b;
            // new values :
            $r = ( $r2 - $r1 != 0 ) ? intval( $r1 + ( $r2 - $r1 ) * ( $i / $line_numbers ) ): $r1;
            $g = ( $g2 - $g1 != 0 ) ? intval( $g1 + ( $g2 - $g1 ) * ( $i / $line_numbers ) ): $g1;
            $b = ( $b2 - $b1 != 0 ) ? intval( $b1 + ( $b2 - $b1 ) * ( $i / $line_numbers ) ): $b1;
            // if new values are really new ones, allocate a new color, otherwise reuse previous color.
            // There's a "feature" in imagecolorallocate that makes this function
            // always returns '-1' after 255 colors have been allocated in an image that was created with
            // imagecreate (everything works fine with imagecreatetruecolor)
            if ( "$old_r,$old_g,$old_b" != "$r,$g,$b") 
                $fill = imagecolorallocatealpha( $im, $r, $g, $b,$this->alpha1 );
            switch($direction) {
                case 'vertical':
                    imagefilledrectangle($im, 0, $i, $line_width, $i+$this->step, $fill);
                    break;
                case 'horizontal':
                    imagefilledrectangle( $im, $i, 0, $i+$this->step, $line_width, $fill );
                    break;
                case 'ellipse':
                case 'ellipse2':
                case 'circle':
                case 'circle2':
                    imagefilledellipse ($im,$center_x, $center_y, ($line_numbers-$i)*$rh, ($line_numbers-$i)*$rw,$fill);
                    break;
                case 'square':
                case 'rectangle':
                    imagefilledrectangle ($im,$i*$width/$height,$i*$height/$width,$width-($i*$width/$height), $height-($i*$height/$width),$fill);
                    break;
                case 'diamond':
                    imagefilledpolygon($im, array (
                        $width/2, $i*$rw-0.5*$height,
                        $i*$rh-0.5*$width, $height/2,
                        $width/2,1.5*$height-$i*$rw,
                        1.5*$width-$i*$rh, $height/2 ), 4, $fill);
                    break;
                default:    
            }        
        }
    }
    
    // #ff00ff -> array(255,0,255) or #f0f -> array(255,0,255)
    function hex2rgb($color) {
        $color = str_replace('#','',$color);
        $s = strlen($color) / 3;
        $rgb[]=hexdec(str_repeat(substr($color,0,$s),2/$s));
        $rgb[]=hexdec(str_repeat(substr($color,$s,$s),2/$s));
        $rgb[]=hexdec(str_repeat(substr($color,2*$s,$s),2/$s));
        return $rgb;
    }
}

function rgb2html($r, $g=-1, $b=-1)
{
    if (is_array($r) && sizeof($r) == 3)
        list($r, $g, $b) = $r;

    $r = intval($r); $g = intval($g);
    $b = intval($b);

    $r = dechex($r<0?0:($r>255?255:$r));
    $g = dechex($g<0?0:($g>255?255:$g));
    $b = dechex($b<0?0:($b>255?255:$b));

    $color = (strlen($r) < 2?'0':'').$r;
    $color .= (strlen($g) < 2?'0':'').$g;
    $color .= (strlen($b) < 2?'0':'').$b;
    return '#'.$color;
}
?>