<?php

if (!class_exists('Imagick'))
    die("Need php5-imagick\n");

$args = $_SERVER['argv'];

$script = array_shift($args); // Filename
$dest = array_pop($args); // Destination file

if (empty($args))
    die("Syntax: $script source1.png source2.png ... destination.png\n");

if (file_exists($dest))
    die("$dest destination already exists\n");

$images = array();
$width = 0;
$height = 0;

foreach ($args as $arg)
{
    if (!preg_match('!\.(?:png|jpe?g|gif)$!i', $arg))
    {
        echo "$arg is not an image\n";
        continue;
    }

    $infos = getimagesize($arg);

    if (!$infos)
    {
        echo "$arg is not a recognized image\n";
        continue;
    }

    $name = basename($arg);
    $name = preg_replace('!\.[a-z]+$!i', '', $name);

    $images[$name] = array(
        'file'  =>  $arg,
        'width' =>  $infos[0],
        'height'=>  $infos[1],
    );

    if ($infos[0] > $width)
        $width = $infos[0];

    $height += $infos[1];
}

if (empty($images))
{
    die("No images to sprite\n");
}

ksort($images);

$pos = 0;
$css = '';

$im = new Imagick;

$im->newImage($width, $height, 'none');
$im->setImageFormat('png');

foreach ($images as $name=>&$image)
{
    $im->compositeImage(new Imagick($image['file']), Imagick::COMPOSITE_OVER, 0, $pos);

    $css .= '.' . $name . ' { background-position: 0px '.($pos ? '-' . $pos : $pos).'px; ';
    $css .= 'width: '.$image['width'].'px; height: '.$image['height'].'px; }';
    $css .= "\n";

    $pos += $image['height'];
}

$im->writeImage($dest);
unset($im);

echo $css;

?>