<?php

/*
 * CSS Mixin, Version 3
 * Copyright 2007-2009 Chuck Houpt
 *
 */

$cssrules = array();
$debug = FALSE;
$setheaders = FALSE;

// ETag based on the same formula as Apache 1.3
function etag($file)
{
 	return sprintf('%x-%x-%x', fileinode($file), filesize($file), filemtime($file));
}

// cssmixin_init must be called first to setup HTTP headers and load base CSS styles.
function cssmixin_init($cssfile, $debugflag)
{
	global $cssrules;
	global $debug;
	global $setheaders;
	
	$debug = $debugflag;

	if (!$setheaders) {
		$setheaders = TRUE;
		$last_modified = max(filemtime($_SERVER['SCRIPT_FILENAME']), filemtime($cssfile));
		$etag = '"' . etag($_SERVER['SCRIPT_FILENAME']) . '-' . etag($cssfile) . '"';
		
		header('Content-type: text/css');
		header('Last-Modified: ' . gmdate('D, d M Y H:i:s', $last_modified) . ' GMT');
		header("ETag: $etag");
		
		if ((isset($_SERVER['HTTP_IF_NONE_MATCH']) && strcmp($_SERVER['HTTP_IF_NONE_MATCH'], $etag) == 0) ||
			(isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) && strtotime($_SERVER['HTTP_IF_MODIFIED_SINCE']) >= $last_modified)) {
			header('HTTP/1.0 304 Not Modified');
			exit;
		}
			
		print("/* Generated by CSS Mixin v3 http://habilis.net/cssmixin/ */\n");
		if ($debug) print("/*\n    PHP Style Script: {$_SERVER['PHP_SELF']}\n      CSS Class File: $cssfile\n*/\n");
	}
	
	// load CSS
	$f = file_get_contents($cssfile);
	
	// Strip all the comments
	$f = preg_replace('/\/\*.*\*\//sU', '', $f);
	
	// Tokenize into selectors, and declariations.
	// It's not a parser, it's a pharser (hackish, kludgy parser).
	preg_match_all('/([>_a-z0-9-:\.\*][>_a-z0-9-:\.\* ]+[>_a-z0-9-:\.\*])|({[^}]+})/si', $f, $out, PREG_SET_ORDER);
	
	//print_r($out);
	
	// Construct descriptor by appending selectors
	$selector_list = array();
	
	foreach ($out as $o) {
		$firstc = $o[0][0];		
		if ($firstc != '{') {
			$selector_list[] = $o[1];
		} else if ($firstc == '{') {
			$descriptor = trim(trim($o[2], ' '), "\n\r");
			foreach ($selector_list as $s) {
				preg_match('/\.([_a-z0-9-]+)/si', $s, $matches);
				$class = $matches[1];
				if (array_key_exists($class, $cssrules)) $cssrules[$class][] = array($s, $descriptor);
				else $cssrules[$class] =  array(array($s, $descriptor));
			}
			$selector_list = array();
		}
	}
	
	//print_r($cssrules);
}

// cssmixin creates new style descriptors for $newspec based on the $mixinclasses list.
function cssmixin($newspec, $mixinclasses)
{
	global $cssrules;
	global $debug;
	
	$clist = explode(' ', $mixinclasses);

	foreach ($clist as $c) {
		if ($debug) {
			print("/* Spec: $newspec Class: $c */\n\n");
		}
		if (array_key_exists($c, $cssrules)) {
			foreach ($cssrules[$c] as $rule) {
				$selector = $rule[0];
				$description = $rule[1];
				$selector = str_replace(".$c", $newspec, $selector);
				print("$selector $description\n\n");
			}
		}
	}
}

?>