<?php

// *** Configuration start

// Web server root path
$web_root = "/Users/daniel/Sites/";

// Cache directory. Need write permissions
$path_cache = "/Users/daniel/Sites/cache/";

// Default photo.
$default_photo = "/default.jpeg";

// Tag
$tag = "http://ruido-blanco.net/blog/";

// *** Configuration end

/*
* Transforms a palette image into a truecolor image. Leaves truecolor images
* untouched.
*/
function imagepalettetotruecolor(&$img)
{
if (!imageistruecolor($img)) { // GIF format is not truecolor
$w = imagesx($img);
$h = imagesy($img);
$img1 = imagecreatetruecolor($w, $h); // Create a new truecolor image
imagecopy($img1, $img, 0, 0, 0, 0, $w, $h); // Copy old image over
$img = $img1; // Change the image handler
}
}

/*
* Process an image. The parameter is the path to the image. The result image is
* saved over the old image.
*/
function process_image($photo)
{
global $tag;

// Create an iamge handler from any known format
$im = imagecreatefromstring(file_get_contents($photo));
imagepalettetotruecolor($im);
$white = imagecolorallocate($im, 255, 255, 255);
$black = imagecolorallocate($im, 0, 0, 0);

// Add the tag using font #2
// Add a background rectangle.
$tag_width = imagefontwidth(2) * strlen($tag) + 1;
$tag_height = imagefontheight(2) + 2;
imagefilledrectangle($im, 0, 0, $tag_width, , $black);
imagestring($im, 2, 1, 1, $tag, $white);

// Save the image in jpeg.
imagejpeg($im, $photo);
imagedestroy($im);
}

// Get the image to "tag"
if ($_GET['photo'] != "") { // URL parameter for testing
$photo_url = $_GET['photo'];
} else if ($_SERVER['REQUEST_URI'] != "") { // Request URL for production
$photo_url = $_SERVER['REQUEST_URI'];
} else { // or a default image
$photo_url = $default_photo;
}

// The path to the real image
$photo_path = $web_root . $photo_url;

// The path to the cached image. The md5 avoids name clashes.
$photo_cache = $path_cache . md5($photo_url);

if (is_file($photo_path)) { // We test if there is really an image
if (!is_file($photo_cache)) { // If the image is not yet cached
// Copy over the cache
copy($photo_path, $photo_cache) or die('Error copying the image');

// Process the cached image
process_image($photo_cache);
}

if (is_file($photo_cache)) { // If we have the image in the cache
// Send the image mime type and length
header("Content-Type: image/jpeg");
header("Content-Length: " . filesize($photo_cache));
readfile($photo_cache);
} else {
die('Image not in the cache');
}
} else {
die('Image not found ' . $photo_url);
}
?>

RewriteEngine on
RewriteCond %{HTTP_REFERER} !^$
RewriteCond %{HTTP_REFERER} !^http://eldominio.com(/)?.*$ [NC]
RewriteRule .*.(gif|jpg|jpeg|bmp|png)$ /image.php [NC]