<?php
/**
 * cssmin.php - A simple CSS minifier.
 * --
 * 
 * <code>
 * include("cssmin.php");
 * file_put_contents("path/to/target.css", cssmin::minify(file_get_contents("path/to/source.css")));
 * </code>
 * --
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING 
 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 * --
 *
 * @package 	cssmin
 * @author 		Joe Scylla <joe.scylla@gmail.com>
 * @copyright 	2008 Joe Scylla <joe.scylla@gmail.com>
 * @license 	http://opensource.org/licenses/mit-license.php MIT License
 * @version 	1.0.1.b2 (2008-08-15)
 */
class cssmin
	{
	/**
	 * Minifies stylesheet definitions
	 *
	 * <code>
	 * $css_minified = cssmin::minify(file_get_contents("path/to/target/file.css"));
	 * </code>
	 * 
	 * @param	string			$css		Stylesheet definitions as string
	 * @param	array|string	$options	Array or comma speperated list of options:
	 * 										- preserve-urls: Preserves every url defined in an url()-
	 * 										expression. This option is only required if you have 
	 * 										defined really uncommon urls with multiple spaces or 
	 * 										combination of colon, semi-colon, braces with leading or 
	 * 										following spaces.
	 * @return	string			Minified stylesheet definitions
	 */
	public static function minify($css, $options = "")
		{
		$options = ($options == "") ? array() : (is_array($options) ? $options : explode(",", $options));
		if (in_array("preserve-urls", $options))
			{
			// Encode url() to base64
			$css = preg_replace_callback("/url\s*\((.*)\)/siU", "cssmin_encode_url", $css);
			}
		// Remove comments
		$css = preg_replace("/\/\*[\d\D]*?\*\/|\t+/", " ", $css);
		// Replace CR, LF and TAB to spaces
		$css = str_replace(array("\n", "\r", "\t"), " ", $css);
		// Replace multiple to single space
		$css = preg_replace("/\s\s+/", " ", $css);
		// Remove unneeded spaces
		$css = preg_replace("/\s*({|}|\[|\]|=|~|\+|>|\||;|:|,)\s*/", "$1", $css);
		$css = trim($css);
		if (in_array("preserve-urls", $options))
			{
			// Decode url()
			$css = preg_replace_callback("/url\s*\((.*)\)/siU", "cssmin_encode_url", $css);
			}
		return $css;
		}
	/**
	 * Return a array structure of a stylesheet definitions.
	 *
	 * <code>
	 * $css_structure = cssmin::toArray(file_get_contents("path/to/target/file.css"));
	 * </code>
	 * 
	 * @param	string		$css			Stylesheet definitions as string
	 * @param	string		$options		Options for {@link cssmin::minify()}
	 * @return	array						Structure of the stylesheet definitions as array
	 */
	public static function toArray($css, $options = "")
		{
		$r = array();
		$css = cssmin::minify($css, $options);
		preg_match_all("/(.+){(.+:.+);}/U", $css, $items);
		if (count($items[0]) > 0)
			{
			for ($i = 0; $i < $c = count($items[0]); $i++)
				{
				$keys		= explode(",", $items[1][$i]);
				$styles_tmp	= explode(";", $items[2][$i]);
				$styles = array();
				foreach ($styles_tmp as $style)
					{
					$style_tmp = explode(":", $style);
					$styles[$style_tmp[0]] = $style_tmp[1];
					}
				$r[] = array
					(
					"keys"		=> cssmin_array_clean($keys),
					"styles"	=> cssmin_array_clean($styles)
					);
				}
			}
		return $r;
		}
	/**
	 * Return a array structure created by {@link cssmin::toArray()} to a string.
	 *
	 * <code>
	 * $css_string = cssmin::toString($css_structure);
	 * </code>
	 * 
	 * @param	array		$css
	 * @return	array
	 */
	public static function toString(array $array)
		{
		$r = "";
		foreach ($array as $item)
			{
			$r .= implode(",", $item["keys"]) . "{";
			foreach ($item["styles"] as $key => $value)
				{
				$r .= $key . ":" . $value . ";";
				}
			$r .= "}";
			}
		return $r;
		}
	}

/**
 * Trims all elements of the array and removes empty elements. 
 *
 * @param	array		$array
 * @return	array
 */
function cssmin_array_clean(array $array)
	{
	$r = array();
	$c = count($v);
	if (cssmin_array_is_assoc($array))
		{
		foreach ($array as $key => $value)
			{
			$r[$key] = trim($value);
			}
		}
	else
		{
		foreach ($array as $value)
			{
			if (trim($value) != "")
				{
				$r[] = trim($value);
				}
			}
		}
	return $r;
	}
/**
 * Return if value is a associative array.
 *
 * @param	array		$array
 * @return	bool
 */
function cssmin_array_is_assoc($array)
	{
	if (!is_array($array))
		{
		return false;
		}
	else
		{
		krsort($array, SORT_STRING);
		return !is_numeric(key($array));
		}
	}
/**
 * Encodes a url() expression.
 *
 * @param	array	$match
 * @return	string
 */
function cssmin_encode_url($match)
	{
	return "url(" . base64_encode(trim($match[1])) . ")";
	}
/**
 * Decodes a url() expression.
 *
 * @param	array	$match
 * @return	string
 */
function cssmin_decode_url($match)
	{
	return "url(" . base64_decode($match[1]) . ")";
	}
?>