<?php

/*
 * Enano - an open-source CMS capable of wiki functions, Drupal-like sidebar blocks, and everything in between
 * Copyright (C) 2006-2009 Dan Fuhry
 * jsres.php - the Enano client-side runtime, a.k.a. AJAX on steroids
 *
 * This program is Free Software; you can redistribute and/or modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for details.
 */

define('ENANO_JS_DEBUG', 1);

// if Enano's already loaded, we've been included from a helper script
if ( defined('ENANO_CONFIG_FETCHED') )
	define('ENANO_JSRES_SETUP_ONLY', 1);

if ( !defined('ENANO_JSRES_SETUP_ONLY') ):

/**
 * Returns a floating-point number with the current UNIX timestamp in microseconds. Defined very early because we gotta call it
 * from very early on in the script to measure the starting time of Enano.
 * @return float
 */

// First check to see if something already declared this function.... it happens often.
if ( !function_exists('microtime_float') )
{
	function microtime_float()
	{
		list($usec, $sec) = explode(" ", microtime());
		return ((float)$usec + (float)$sec);
	}
}

$local_start = microtime_float();

// Disable for IE, it causes problems.
$disable_compress = ( strstr(@$_SERVER['HTTP_USER_AGENT'], 'MSIE') || defined('ENANO_JS_DEBUG') ) && !isset($_GET['early']);

// Setup Enano

//
// Determine the location of Enano as an absolute path.
//

// We need to see if this is a specially marked Enano development server. You can create an Enano
// development server using the script found on hg.enanocms.org.
if ( strpos(__FILE__, '/repo/') && ( file_exists('../../.enanodev') || file_exists('../../../.enanodev') ) )
{
	// We have a development directory. Remove /repo/ from the picture.
	$filename = str_replace('/repo/', '/', __FILE__);
}
else
{
	// Standard Enano installation
	$filename = __FILE__;
}

// ENANO_ROOT is sometimes defined by plugins like AjIM that need the constant before the Enano API is initialized
if ( !defined('ENANO_ROOT') )
	define('ENANO_ROOT', dirname(dirname(dirname($filename))));

chdir(ENANO_ROOT);

// fetch only the site config
define('ENANO_EXIT_AFTER_CONFIG', 1);
require('includes/common.php');

endif; // ENANO_JSRES_SETUP_ONLY

// CONFIG

// Files safe to run full (aggressive) compression on
$full_compress_safe = array(
	// Sorted by file size, descending (du -b *.js | sort -n)
	'crypto.js',
	'ajax.js',
	'editor.js',
	'functions.js',
	'login.js',
	'acl.js',
	'misc.js',
	'comments.js',
	'autofill.js',
	'dropdown.js',
	'paginate.js',
	'enano-lib-basic.js',
	'pwstrength.js',
	'flyin.js',
	'rank-manager.js',
	'userpage.js',
	'template-compiler.js',
	'toolbar.js',
);

// Files that should NOT be compressed due to already being compressed, licensing, or invalid produced code
$compress_unsafe = array('json.js', 'fat.js', 'admin-menu.js', 'autofill.js', 'jquery.js', 'jquery-ui.js');

require_once('includes/js-compressor.php');

// try to gzip the output
if ( !defined('ENANO_JSRES_SETUP_ONLY') ):
$do_gzip = false;
if ( isset($_SERVER['HTTP_ACCEPT_ENCODING']) && getConfig('gzip_output', false) == 1 )
{
	$acceptenc = str_replace(' ', '', strtolower($_SERVER['HTTP_ACCEPT_ENCODING']));
	$acceptenc = explode(',', $acceptenc);
	if ( in_array('gzip', $acceptenc) )
	{
		$do_gzip = true;
		ob_start();
	}
}

// Output format will always be JS
header('Content-type: text/javascript');

endif; // ENANO_JSRES_SETUP_ONLY

$everything = "/* The code represented in this file is compressed for optimization purposes. The full source code is available in includes/clientside/static/. */\n\nvar ENANO_JSRES_COMPRESSED = true;\n\n";

// if we only want the tiny version of the API (just enough to get by until the full one is loaded), send that
// with a simple ETag and far future expires header

// note - obfuscated for optimization purposes. The exact same code except properly indented is in enano-lib-basic.
if ( isset($_GET['early']) )
{
	header('ETag: enanocms-lib-early-r3');
	header('Expires: Wed, 1 Jan 2020 00:00:00 GMT');
	
	echo <<<JSEOF
window.loaded_components = window.loaded_components || {};
window.onload_complete = false;
var onload_hooks = new Array();function addOnloadHook(func){if ( typeof ( func ) == 'function' ){if ( typeof(onload_hooks.push) == 'function' ){onload_hooks.push(func);}else{onload_hooks[onload_hooks.length] = func;};};}
JSEOF;
	
	exit();
}

// Load and parse enano_lib_basic
$file = @file_get_contents('includes/clientside/static/enano-lib-basic.js');

$pos_start_includes = strpos($file, '/*!START_INCLUDER*/');
$pos_end_includes = strpos($file, '/*!END_INCLUDER*/');

if ( !$pos_start_includes || !$pos_end_includes )
{
	die('// Error: enano-lib-basic does not have required metacomments');
}

$pos_end_includes += strlen('/*!END_INCLUDER*/');

preg_match('/var thefiles = (\[([^\]]+?)\]);/', $file, $match);

if ( empty($match) )
	die('// Error: could not retrieve file list from enano-lib-basic');

// Decode file list
try
{
	$file_list = enano_json_decode($match[1]);
}
catch ( Exception $e )
{
	die("// Exception caught during file list parsing");
}

$apex = filemtime('includes/clientside/static/enano-lib-basic.js');

$before_includes = substr($file, 0, $pos_start_includes);
$after_includes = substr($file, $pos_end_includes);

if ( isset($_GET['f']) )
{
	// requested a single file
	$js_file =& $_GET['f'];
	if ( strstr($js_file, ',') )
	{
		$filelist = explode(',', $js_file);
		unset($js_file);
		$everything = '';
		foreach ( $filelist as $js_file )
		{
			if ( !preg_match('/^[a-z0-9_-]+\.js$/i', $js_file) )
			{
				header('HTTP/1.1 404 Not Found');
				exit('Not found');
			}
			
			$apex = filemtime("includes/clientside/static/$js_file");
			
			$file_contents = file_get_contents("includes/clientside/static/$js_file");
			$everything .= jsres_cache_check($js_file, $file_contents) . ' loaded_components[\'' . $js_file . '\'] = true;';
		}
		$everything .= 'if ( onload_complete ) { runOnloadHooks(); onload_hooks = []; };';
	}
	else
	{
		if ( !preg_match('/^[a-z0-9_-]+\.js$/i', $js_file) )
		{
			header('HTTP/1.1 404 Not Found');
			exit('Not found');
		}
		
		$apex = filemtime("includes/clientside/static/$js_file");
		
		$file_contents = file_get_contents("includes/clientside/static/$js_file");
		$everything = jsres_cache_check($js_file, $file_contents) . ' loaded_components[\'' . $js_file . '\'] = true; if ( onload_complete ) { runOnloadHooks(); onload_hooks = []; };';
	}
}
else
{
	// compress enano-lib-basic
	$libbasic = "$before_includes\n$after_includes";
	$libbasic = jsres_cache_check('enano-lib-basic.js', $libbasic);
	$everything .= $libbasic;
	
	// $everything .= $before_includes;
	// $everything .= $after_includes;
	
	foreach ( $file_list as $js_file )
	{
		$file_contents = file_get_contents("includes/clientside/static/$js_file");
		$time = filemtime("includes/clientside/static/$js_file");
		if ( $time > $apex )
			$apex = $time;
		
		$file_contents = jsres_cache_check($js_file, $file_contents);
		
		$everything .= "\n\n// $js_file\n";
		$everything .= "\n" . $file_contents;
	}
}

// generate ETag
$etag = base64_encode(hexdecode(sha1($everything)));

if ( isset($_SERVER['HTTP_IF_NONE_MATCH']) )
{
	if ( "\"$etag\"" == $_SERVER['HTTP_IF_NONE_MATCH'] )
	{
		header('HTTP/1.1 304 Not Modified');
		exit();
	}
}

// generate expires header
$expires = date('r', mktime(0, 0, 0, intval(date('m')), intval(date('d')), intval(date('y'))+1));

$everything = str_replace('/* JavaScriptCompressor 0.8 [www.devpro.it], thanks to Dean Edwards for idea [dean.edwards.name] */' . "\r\n", '', $everything);

$date = date('r', $apex);

if ( defined('ENANO_JSRES_SETUP_ONLY') )
{
	return; // we're done setting up, break out
}

header("Date: $date");
header("Last-Modified: $date");
header("ETag: \"$etag\"");
header("Expires: $expires");
if ( !$do_gzip )
	header("Content-Length: " . strlen($everything));

$local_end = microtime_float();
$local_gentime = $local_end - $local_start;
$local_gentime = round($local_gentime, 5);
header("X-Performance: generated in $local_gentime seconds");

echo $everything;

if ( $do_gzip )
{
	gzip_output();
}

/**
 * Check the cache for the given JS file and return the best-compressed version.
 * @param string Javascript file (acl.js)
 * @param string Default/current contents
 * @return string
 */

function jsres_cache_check($js_file, $file_contents)
{
	global $full_compress_safe, $compress_unsafe;
	global $disable_compress;
	
	if ( $disable_compress )
		return $file_contents;
	
	$file_md5 = md5($file_contents);
	
	// Is this file cached?
	$cache_path = ENANO_ROOT . "/cache/jsres_$js_file.json";
	$loaded_cache = false;
	
	if ( file_exists($cache_path) )
	{
		// Load the cache file and parse it.
		$cache_file = file_get_contents($cache_path);
		try
		{
			$cache_file = enano_json_decode($cache_file);
		}
		catch ( Exception $e )
		{
			// Don't do anything - let our fallbacks come into place
		}
		if ( is_array($cache_file) && isset($cache_file['md5']) && isset($cache_file['src']) )
		{
			if ( $cache_file['md5'] === $file_md5 )
			{
				@header("X-Cache-Status: cache HIT, hash $file_md5");
				$loaded_cache = true;
				$file_contents = $cache_file['src'];
			}
		}
	}
	if ( !$loaded_cache && getConfig('cache_thumbs') == '1' )
	{
		// Try to open the cache file and write to it. If we can't do that, just don't compress the code.
		$handle = @fopen($cache_path, 'w');
		if ( $handle )
		{
			$aggressive = in_array($js_file, $full_compress_safe);
			if ( !in_array($js_file, $compress_unsafe) )
				$file_contents = perform_js_compress($file_contents, $aggressive);
			
			$payload = enano_json_encode(array(
					'md5' => $file_md5,
					'src' => $file_contents
				));
			fwrite($handle, $payload);
			fclose($handle);
			@header("X-Cache-Status: cache MISS, new generated");
		}
		else
		{
			@header("X-Cache-Status: cache MISS, not generated");
		}
	}
	else if ( !$loaded_cache )
	{
		@header("X-Cache-Status: cache MISS, not generated");
	}
	
	return $file_contents;
}