<?php
/**
 * Class Minify 
 * @package Minify
 */
 
/**
 * Minify - Combines, minifies, and caches JavaScript and CSS files on demand.
 *
 * See README for usage instructions (for now).
 *
 * This library was inspired by {@link mailto:flashkot@mail.ru jscsscomp by Maxim Martynyuk}
 * and by the article {@link http://www.hunlock.com/blogs/Supercharged_Javascript "Supercharged JavaScript" by Patrick Hunlock}.
 *
 * Requires PHP 5.1.0.
 * Tested on PHP 5.1.6.
 *
 * @package Minify
 * @author Ryan Grove <ryan@wonko.com>
 * @author Stephen Clay <steve@mrclay.org>
 * @copyright 2008 Ryan Grove, Stephen Clay. All rights reserved.
 * @license http://opensource.org/licenses/bsd-license.php New BSD License
 * @link http://code.google.com/p/minify/
 */
class Minify {
 
 const VERSION = '2.1.7';
 const TYPE_CSS = 'text/css';
 const TYPE_HTML = 'text/html';
 // there is some debate over the ideal JS Content-Type, but this is the
 // Apache default and what Yahoo! uses..
 const TYPE_JS = 'application/x-javascript';
 const URL_DEBUG = 'http://code.google.com/p/minify/wiki/Debugging';
 
 /**
 * How many hours behind are the file modification times of uploaded files?
 * 
 * If you upload files from Windows to a non-Windows server, Windows may report
 * incorrect mtimes for the files. Immediately after modifying and uploading a 
 * file, use the touch command to update the mtime on the server. If the mtime 
 * jumps ahead by a number of hours, set this variable to that number. If the mtime 
 * moves back, this should not be needed.
 *
 * @var int $uploaderHoursBehind
 */
 public static $uploaderHoursBehind = 0;
 
 /**
 * If this string is not empty AND the serve() option 'bubbleCssImports' is
 * NOT set, then serve() will check CSS files for @import declarations that
 * appear too late in the combined stylesheet. If found, serve() will prepend
 * the output with this warning.
 *
 * @var string $importWarning
 */
 public static $importWarning = "/* See http://code.google.com/p/minify/wiki/CommonProblems#@imports_can_appear_in_invalid_locations_in_combined_CSS_files */\n";

 /**
 * Has the DOCUMENT_ROOT been set in user code?
 * 
 * @var bool
 */
 public static $isDocRootSet = false;

 /**
 * Specify a cache object (with identical interface as Minify_Cache_File) or
 * a path to use with Minify_Cache_File.
 * 
 * If not called, Minify will not use a cache and, for each 200 response, will 
 * need to recombine files, minify and encode the output.
 *
 * @param mixed $cache object with identical interface as Minify_Cache_File or
 * a directory path, or null to disable caching. (default = '')
 * 
 * @param bool $fileLocking (default = true) This only applies if the first
 * parameter is a string.
 *
 * @return null
 */
 public static function setCache($cache = '', $fileLocking = true)
 {
 if (is_string($cache)) {
 self::$_cache = new Minify_Cache_File($cache, $fileLocking);
 } else {
 self::$_cache = $cache;
 }
 }
 
 /**
 * Serve a request for a minified file. 
 * 
 * Here are the available options and defaults in the base controller:
 * 
 * 'isPublic' : send "public" instead of "private" in Cache-Control 
 * headers, allowing shared caches to cache the output. (default true)
 * 
 * 'quiet' : set to true to have serve() return an array rather than sending
 * any headers/output (default false)
 * 
 * 'encodeOutput' : set to false to disable content encoding, and not send
 * the Vary header (default true)
 * 
 * 'encodeMethod' : generally you should let this be determined by 
 * HTTP_Encoder (leave null), but you can force a particular encoding
 * to be returned, by setting this to 'gzip' or '' (no encoding)
 * 
 * 'encodeLevel' : level of encoding compression (0 to 9, default 9)
 * 
 * 'contentTypeCharset' : appended to the Content-Type header sent. Set to a falsey
 * value to remove. (default 'utf-8') 
 * 
 * 'maxAge' : set this to the number of seconds the client should use its cache
 * before revalidating with the server. This sets Cache-Control: max-age and the
 * Expires header. Unlike the old 'setExpires' setting, this setting will NOT
 * prevent conditional GETs. Note this has nothing to do with server-side caching.
 * 
 * 'rewriteCssUris' : If true, serve() will automatically set the 'currentDir'
 * minifier option to enable URI rewriting in CSS files (default true)
 * 
 * 'bubbleCssImports' : If true, all @import declarations in combined CSS
 * files will be move to the top. Note this may alter effective CSS values
 * due to a change in order. (default false)
 * 
 * 'debug' : set to true to minify all sources with the 'Lines' controller, which
 * eases the debugging of combined files. This also prevents 304 responses.
 * @see Minify_Lines::minify()
 * 
 * 'minifiers' : to override Minify's default choice of minifier function for 
 * a particular content-type, specify your callback under the key of the 
 * content-type:
 * <code>
 * // call customCssMinifier($css) for all CSS minification
 * $options['minifiers'][Minify::TYPE_CSS] = 'customCssMinifier';
 * 
 * // don't minify Javascript at all
 * $options['minifiers'][Minify::TYPE_JS] = '';
 * </code>
 * 
 * 'minifierOptions' : to send options to the minifier function, specify your options
 * under the key of the content-type. E.g. To send the CSS minifier an option: 
 * <code>
 * // give CSS minifier array('optionName' => 'optionValue') as 2nd argument 
 * $options['minifierOptions'][Minify::TYPE_CSS]['optionName'] = 'optionValue';
 * </code>
 * 
 * 'contentType' : (optional) this is only needed if your file extension is not 
 * js/css/html. The given content-type will be sent regardless of source file
 * extension, so this should not be used in a Groups config with other
 * Javascript/CSS files.
 * 
 * Any controller options are documented in that controller's setupSources() method.
 * 
 * @param mixed $controller instance of subclass of Minify_Controller_Base or string
 * name of controller. E.g. 'Files'
 * 
 * @param array $options controller/serve options
 * 
 * @return null|array if the 'quiet' option is set to true, an array
 * with keys "success" (bool), "statusCode" (int), "content" (string), and
 * "headers" (array).
 *
 * @throws Exception
 */
 public static function serve($controller, $options = array())
 {
 if (! self::$isDocRootSet && 0 === stripos(PHP_OS, 'win')) {
 self::setDocRoot();
 }

 if (is_string($controller)) {
 // make $controller into object
 $class = 'Minify_Controller_' . $controller;
 $controller = new $class();
 /* @var Minify_Controller_Base $controller */
 }
 
 // set up controller sources and mix remaining options with
 // controller defaults
 $options = $controller->setupSources($options);
 $options = $controller->analyzeSources($options);
 self::$_options = $controller->mixInDefaultOptions($options);
 
 // check request validity
 if (! $controller->sources) {
 // invalid request!
 if (! self::$_options['quiet']) {
 self::_errorExit(self::$_options['badRequestHeader'], self::URL_DEBUG);
 } else {
 list(,$statusCode) = explode(' ', self::$_options['badRequestHeader']);
 return array(
 'success' => false
 ,'statusCode' => (int)$statusCode
 ,'content' => ''
 ,'headers' => array()
 );
 }
 }
 
 self::$_controller = $controller;
 
 if (self::$_options['debug']) {
 self::_setupDebug($controller->sources);
 self::$_options['maxAge'] = 0;
 }
 
 // determine encoding
 if (self::$_options['encodeOutput']) {
 $sendVary = true;
 if (self::$_options['encodeMethod'] !== null) {
 // controller specifically requested this
 $contentEncoding = self::$_options['encodeMethod'];
 } else {
 // sniff request header
 // depending on what the client accepts, $contentEncoding may be
 // 'x-gzip' while our internal encodeMethod is 'gzip'. Calling
 // getAcceptedEncoding(false, false) leaves out compress and deflate as options.
 list(self::$_options['encodeMethod'], $contentEncoding) = HTTP_Encoder::getAcceptedEncoding(false, false);
 $sendVary = ! HTTP_Encoder::isBuggyIe();
 }
 } else {
 self::$_options['encodeMethod'] = ''; // identity (no encoding)
 }
 
 // check client cache
 $cgOptions = array(
 'lastModifiedTime' => self::$_options['lastModifiedTime']
 ,'isPublic' => self::$_options['isPublic']
 ,'encoding' => self::$_options['encodeMethod']
 );
 if (self::$_options['maxAge'] > 0) {
 $cgOptions['maxAge'] = self::$_options['maxAge'];
 } elseif (self::$_options['debug']) {
 $cgOptions['invalidate'] = true;
 }
 $cg = new HTTP_ConditionalGet($cgOptions);
 if ($cg->cacheIsValid) {
 // client's cache is valid
 if (! self::$_options['quiet']) {
 $cg->sendHeaders();
 return;
 } else {
 return array(
 'success' => true
 ,'statusCode' => 304
 ,'content' => ''
 ,'headers' => $cg->getHeaders()
 );
 }
 } else {
 // client will need output
 $headers = $cg->getHeaders();
 unset($cg);
 }
 
 if (self::$_options['contentType'] === self::TYPE_CSS
 && self::$_options['rewriteCssUris']) {
 foreach($controller->sources as $key => $source) {
 if ($source->filepath 
 && !isset($source->minifyOptions['currentDir'])
 && !isset($source->minifyOptions['prependRelativePath'])
 ) {
 $source->minifyOptions['currentDir'] = dirname($source->filepath);
 }
 }
 }
 
 // check server cache
 if (null !== self::$_cache && ! self::$_options['debug']) {
 // using cache
 // the goal is to use only the cache methods to sniff the length and 
 // output the content, as they do not require ever loading the file into
 // memory.
 $cacheId = self::_getCacheId();
 $fullCacheId = (self::$_options['encodeMethod'])
 ? $cacheId . '.gz'
 : $cacheId;
 // check cache for valid entry
 $cacheIsReady = self::$_cache->isValid($fullCacheId, self::$_options['lastModifiedTime']); 
 if ($cacheIsReady) {
 $cacheContentLength = self::$_cache->getSize($fullCacheId); 
 } else {
 // generate & cache content
 try {
 $content = self::_combineMinify();
 } catch (Exception $e) {
 self::$_controller->log($e->getMessage());
 if (! self::$_options['quiet']) {
 self::_errorExit(self::$_options['errorHeader'], self::URL_DEBUG);
 }
 throw $e;
 }
 self::$_cache->store($cacheId, $content);
 if (function_exists('gzencode') && self::$_options['encodeMethod']) {
 self::$_cache->store($cacheId . '.gz', gzencode($content, self::$_options['encodeLevel']));
 }
 }
 } else {
 // no cache
 $cacheIsReady = false;
 try {
 $content = self::_combineMinify();
 } catch (Exception $e) {
 self::$_controller->log($e->getMessage());
 if (! self::$_options['quiet']) {
 self::_errorExit(self::$_options['errorHeader'], self::URL_DEBUG);
 }
 throw $e;
 }
 }
 if (! $cacheIsReady && self::$_options['encodeMethod']) {
 // still need to encode
 $content = gzencode($content, self::$_options['encodeLevel']);
 }
 
 // add headers
 $headers['Content-Length'] = $cacheIsReady
 ? $cacheContentLength
 : ((function_exists('mb_strlen') && ((int)ini_get('mbstring.func_overload') & 2))
 ? mb_strlen($content, '8bit')
 : strlen($content)
 );
 $headers['Content-Type'] = self::$_options['contentTypeCharset']
 ? self::$_options['contentType'] . '; charset=' . self::$_options['contentTypeCharset']
 : self::$_options['contentType'];
 if (self::$_options['encodeMethod'] !== '') {
 $headers['Content-Encoding'] = $contentEncoding;
 }
 if (self::$_options['encodeOutput'] && $sendVary) {
 $headers['Vary'] = 'Accept-Encoding';
 }

 if (! self::$_options['quiet']) {
 // output headers & content
 foreach ($headers as $name => $val) {
 header($name . ': ' . $val);
 }
 if ($cacheIsReady) {
 self::$_cache->display($fullCacheId);
 } else {
 echo $content;
 }
 } else {
 return array(
 'success' => true
 ,'statusCode' => 200
 ,'content' => $cacheIsReady
 ? self::$_cache->fetch($fullCacheId)
 : $content
 ,'headers' => $headers
 );
 }
 }
 
 /**
 * Return combined minified content for a set of sources
 *
 * No internal caching will be used and the content will not be HTTP encoded.
 * 
 * @param array $sources array of filepaths and/or Minify_Source objects
 * 
 * @param array $options (optional) array of options for serve. By default
 * these are already set: quiet = true, encodeMethod = '', lastModifiedTime = 0.
 * 
 * @return string
 */
 public static function combine($sources, $options = array())
 {
 $cache = self::$_cache;
 self::$_cache = null;
 $options = array_merge(array(
 'files' => (array)$sources
 ,'quiet' => true
 ,'encodeMethod' => ''
 ,'lastModifiedTime' => 0
 ), $options);
 $out = self::serve('Files', $options);
 self::$_cache = $cache;
 return $out['content'];
 }
 
 /**
 * Set $_SERVER['DOCUMENT_ROOT']. On IIS, the value is created from SCRIPT_FILENAME and SCRIPT_NAME.
 * 
 * @param string $docRoot value to use for DOCUMENT_ROOT
 */
 public static function setDocRoot($docRoot = '')
 {
 self::$isDocRootSet = true;
 if ($docRoot) {
 $_SERVER['DOCUMENT_ROOT'] = $docRoot;
 } elseif (isset($_SERVER['SERVER_SOFTWARE'])
 && 0 === strpos($_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/')) {
 $_SERVER['DOCUMENT_ROOT'] = substr(
 $_SERVER['SCRIPT_FILENAME']
 ,0
 ,strlen($_SERVER['SCRIPT_FILENAME']) - strlen($_SERVER['SCRIPT_NAME']));
 $_SERVER['DOCUMENT_ROOT'] = rtrim($_SERVER['DOCUMENT_ROOT'], '\\');
 }
 }
 
 /**
 * Any Minify_Cache_* object or null (i.e. no server cache is used)
 *
 * @var Minify_Cache_File
 */
 private static $_cache = null;
 
 /**
 * Active controller for current request
 *
 * @var Minify_Controller_Base
 */
 protected static $_controller = null;
 
 /**
 * Options for current request
 *
 * @var array
 */
 protected static $_options = null;

 /**
 * @param string $header
 *
 * @param string $url
 */
 protected static function _errorExit($header, $url)
 {
 $url = htmlspecialchars($url, ENT_QUOTES);
 list(,$h1) = explode(' ', $header, 2);
 $h1 = htmlspecialchars($h1);
 // FastCGI environments require 3rd arg to header() to be set
 list(, $code) = explode(' ', $header, 3);
 header($header, true, $code);
 header('Content-Type: text/html; charset=utf-8');
 echo "<h1>$h1</h1>";
 echo "<p>Please see <a href='$url'>$url</a>.</p>";
 exit();
 }

 /**
 * Set up sources to use Minify_Lines
 *
 * @param Minify_Source[] $sources Minify_Source instances
 */
 protected static function _setupDebug($sources)
 {
 foreach ($sources as $source) {
 $source->minifier = array('Minify_Lines', 'minify');
 $id = $source->getId();
 $source->minifyOptions = array(
 'id' => (is_file($id) ? basename($id) : $id)
 );
 }
 }
 
 /**
 * Combines sources and minifies the result.
 *
 * @return string
 *
 * @throws Exception
 */
 protected static function _combineMinify()
 {
 $type = self::$_options['contentType']; // ease readability
 
 // when combining scripts, make sure all statements separated and
 // trailing single line comment is terminated
 $implodeSeparator = ($type === self::TYPE_JS)
 ? "\n;"
 : '';
 // allow the user to pass a particular array of options to each
 // minifier (designated by type). source objects may still override
 // these
 $defaultOptions = isset(self::$_options['minifierOptions'][$type])
 ? self::$_options['minifierOptions'][$type]
 : array();
 // if minifier not set, default is no minification. source objects
 // may still override this
 $defaultMinifier = isset(self::$_options['minifiers'][$type])
 ? self::$_options['minifiers'][$type]
 : false;

 // process groups of sources with identical minifiers/options
 $content = array();
 $i = 0;
 $l = count(self::$_controller->sources);
 $groupToProcessTogether = array();
 $lastMinifier = null;
 $lastOptions = null;
 do {
 // get next source
 $source = null;
 if ($i < $l) {
 $source = self::$_controller->sources[$i];
 /* @var Minify_Source $source */
 $sourceContent = $source->getContent();

 // allow the source to override our minifier and options
 $minifier = (null !== $source->minifier)
 ? $source->minifier
 : $defaultMinifier;
 $options = (null !== $source->minifyOptions)
 ? array_merge($defaultOptions, $source->minifyOptions)
 : $defaultOptions;
 }
 // do we need to process our group right now?
 if ($i > 0 // yes, we have at least the first group populated
 && (
 ! $source // yes, we ran out of sources
 || $type === self::TYPE_CSS // yes, to process CSS individually (avoiding PCRE bugs/limits)
 || $minifier !== $lastMinifier // yes, minifier changed
 || $options !== $lastOptions) // yes, options changed
 )
 {
 // minify previous sources with last settings
 $imploded = implode($implodeSeparator, $groupToProcessTogether);
 $groupToProcessTogether = array();
 if ($lastMinifier) {
 try {
 $content[] = call_user_func($lastMinifier, $imploded, $lastOptions);
 } catch (Exception $e) {
 throw new Exception("Exception in minifier: " . $e->getMessage());
 }
 } else {
 $content[] = $imploded;
 }
 }
 // add content to the group
 if ($source) {
 $groupToProcessTogether[] = $sourceContent;
 $lastMinifier = $minifier;
 $lastOptions = $options;
 }
 $i++;
 } while ($source);

 $content = implode($implodeSeparator, $content);
 
 if ($type === self::TYPE_CSS && false !== strpos($content, '@import')) {
 $content = self::_handleCssImports($content);
 }
 
 // do any post-processing (esp. for editing build URIs)
 if (self::$_options['postprocessorRequire']) {
 require_once self::$_options['postprocessorRequire'];
 }
 if (self::$_options['postprocessor']) {
 $content = call_user_func(self::$_options['postprocessor'], $content, $type);
 }
 return $content;
 }
 
 /**
 * Make a unique cache id for for this request.
 * 
 * Any settings that could affect output are taken into consideration 
 *
 * @param string $prefix
 *
 * @return string
 */
 protected static function _getCacheId($prefix = 'minify')
 {
 $name = preg_replace('/[^a-zA-Z0-9\\.=_,]/', '', self::$_controller->selectionId);
 $name = preg_replace('/\\.+/', '.', $name);
 $name = substr($name, 0, 200 - 34 - strlen($prefix));
 $md5 = md5(serialize(array(
 Minify_Source::getDigest(self::$_controller->sources)
 ,self::$_options['minifiers'] 
 ,self::$_options['minifierOptions']
 ,self::$_options['postprocessor']
 ,self::$_options['bubbleCssImports']
 ,self::VERSION
 )));
 return "{$prefix}_{$name}_{$md5}";
 }
 
 /**
 * Bubble CSS @imports to the top or prepend a warning if an import is detected not at the top.
 *
 * @param string $css
 *
 * @return string
 */
 protected static function _handleCssImports($css)
 {
 if (self::$_options['bubbleCssImports']) {
 // bubble CSS imports
 preg_match_all('/@import.*?;/', $css, $imports);
 $css = implode('', $imports[0]) . preg_replace('/@import.*?;/', '', $css);
 } else if ('' !== self::$importWarning) {
 // remove comments so we don't mistake { in a comment as a block
 $noCommentCss = preg_replace('@/\\*[\\s\\S]*?\\*/@', '', $css);
 $lastImportPos = strrpos($noCommentCss, '@import');
 $firstBlockPos = strpos($noCommentCss, '{');
 if (false !== $lastImportPos
 && false !== $firstBlockPos
 && $firstBlockPos < $lastImportPos
 ) {
 // { appears before @import : prepend warning
 $css = self::$importWarning . $css;
 }
 }
 return $css;
 }
}