<?php
/**
 * tiny_mce_gzip.php
 *
 * Copyright 2010, Moxiecode Systems AB
 * Released under LGPL License.
 *
 * License: http://tinymce.moxiecode.com/license
 * Contributing: http://tinymce.moxiecode.com/contributing
 */

$frameworkPath = rtrim(dirname(dirname(dirname(__FILE__))), DIRECTORY_SEPARATOR);
$basePath = rtrim(dirname($frameworkPath), DIRECTORY_SEPARATOR);

require_once $frameworkPath . '/core/Constants.php';

// Handle incoming request if it's a script call
if (TinyMCE_Compressor::getParam("js")) {
	// Default settings
	$tinyMCECompressor = new TinyMCE_Compressor(array(
		// CUSTOM SilverStripe
		'cache_dir' => TEMP_FOLDER
		// CUSTOM END
	));

	// Handle request, compress and stream to client
	$tinyMCECompressor->handleRequest();
}

/**
 * This class combines and compresses the TinyMCE core, plugins, themes and
 * language packs into one disk cached gzipped request. It improves the loading speed of TinyMCE dramatically but
 * still provides dynamic initialization.
 *
 * Example of direct usage:
 * require_once("../jscripts/tiny_mce/tiny_mce_gzip.php");
 *
 * // Renders script tag with compressed scripts
 * TinyMCE_Compressor::renderTag(array(
 *    "url" => "../jscripts/tiny_mce/tiny_mce_gzip.php",
 *    "plugins" => "pagebreak,style",
 *    "themes" => "advanced",
 *    "languages" => "en"
 * ));
 */
class TinyMCE_Compressor {
	private $files, $settings;
	private static $defaultSettings = array(
		"plugins"    => "",
		"themes"     => "",
		"languages"  => "",
		"disk_cache" => true,
		"expires"    => "30d",
		"cache_dir"  => "",
		"compress"   => true,
		"suffix"     => "",
		"files"      => "",
		"source"     => false,
	);

	/**
	 * Constructs a new compressor instance.
	 *
	 * @param Array $settings Name/value array with non-default settings for the compressor instance.
	 */
	public function __construct($settings = array()) {
		$this->settings = array_merge(self::$defaultSettings, $settings);

		if (empty($this->settings["cache_dir"]))
			$this->settings["cache_dir"] = dirname(__FILE__);
	}

	/**
	 * Adds a file to the concatenation/compression process.
	 *
	 * @param String $path Path to the file to include in the compressed package/output.
	 */
	public function &addFile($file) {
		$this->files .= ($this->files ? "," : "") . $file;

		return $this;
	}

	/**
	 * Handles the incoming HTTP request and sends back a compressed script depending on settings and client support.
	 */
	public function handleRequest() {
		$files = array();
		$supportsGzip = false;
		$expiresOffset = $this->parseTime($this->settings["expires"]);
		$tinymceDir = dirname(__FILE__);

		// Override settings with querystring params
		$plugins = self::getParam("plugins");
		if ($plugins)
			$this->settings["plugins"] = $plugins;
		$plugins = array_unique(explode(',', $this->settings["plugins"]));

		$themes = self::getParam("themes");
		if ($themes)
			$this->settings["themes"] = $themes;
		$themes = array_unique(explode(',', $this->settings["themes"]));

		$languages = self::getParam("languages");
		if ($languages)
			$this->settings["languages"] = $languages;
		$languages = array_unique(explode(',', $this->settings["languages"]));

		$tagFiles = self::getParam("files");
		if ($tagFiles)
			$this->settings["files"] = $tagFiles;

		$diskCache = self::getParam("diskcache");
		if ($diskCache)
			$this->settings["disk_cache"] = ($diskCache === "true");

		$src = self::getParam("src");
		if ($src)
			$this->settings["source"] = ($src === "true");

		// Add core
		$files[] = "tiny_mce";
		foreach ($languages as $language)
			$files[] = "langs/$language";

		// Add plugins
		foreach ($plugins as $plugin) {
			$files[] = "plugins/$plugin/editor_plugin";

			foreach ($languages as $language)
				$files[] = "plugins/$plugin/langs/$language";
		}

		// Add themes
		foreach ($themes as $theme) {
			$files[] = "themes/$theme/editor_template";

			foreach ($languages as $language)
				$files[] = "themes/$theme/langs/$language";
		}

		// Add any specified files.
		$allFiles = array_merge($files, array_unique(explode(',', $this->settings['files'])));

		// Process source files
		for ($i = 0; $i < count($allFiles); $i++) {
			$file = $allFiles[$i];

			if ($this->settings["source"] && file_exists($file . "_src.js")) {
				$file .= "_src.js";
			} else if (file_exists($file . ".js"))  {
				$file .= ".js";
			} else {
				$file = "";
			}

			$allFiles[$i] = $file;
		}

		// Generate hash for all files, and script path so multiple projects don't share the same cache
		$hash = md5(implode('', $allFiles) . $_SERVER['SCRIPT_NAME']);

		// Check if it supports gzip
		$zlibOn = ini_get('zlib.output_compression') || (ini_set('zlib.output_compression', 0) === false);
		$encodings = (isset($_SERVER['HTTP_ACCEPT_ENCODING'])) ? strtolower($_SERVER['HTTP_ACCEPT_ENCODING']) : "";
		$encoding = preg_match( '/\b(x-gzip|gzip)\b/', $encodings, $match) ? $match[1] : "";

		// Is northon antivirus header
		if (isset($_SERVER['---------------']))
			$encoding = "x-gzip";

		$supportsGzip = $this->settings['compress'] && !empty($encoding) && !$zlibOn && function_exists('gzencode');

		// Set cache file name
		$cacheFile = $this->settings["cache_dir"] . "/" . $hash . ($supportsGzip ? ".gz" : ".js");
 		// Set headers
		header("Content-type: text/javascript");
		header("Vary: Accept-Encoding");  // Handle proxies
		header("Expires: " . gmdate("D, d M Y H:i:s", time() + $expiresOffset) . " GMT");
		header("Cache-Control: public, max-age=" . $expiresOffset);

		if ($supportsGzip)
			header("Content-Encoding: " . $encoding);

		// Use cached file
		if ($this->settings['disk_cache'] && file_exists($cacheFile)) {
			readfile($cacheFile);
			return;
		}

		// Set base URL for where tinymce is loaded from
		$buffer = "var tinyMCEPreInit={base:'" . dirname($_SERVER["SCRIPT_NAME"]) . "',suffix:''};";

		// Load all tinymce script files into buffer
		foreach ($allFiles as $file) {
			if ($file) {
				$fileContents = $this->getFileContents($tinymceDir . "/" . $file);
//				$buffer .= "\n//-FILE-$tinymceDir/$file (". strlen($fileContents) . " bytes)\n";
				$buffer .= $fileContents;
			}
		}

		// Mark all themes, plugins and languages as done
		$buffer .= 'tinymce.each("' . implode(',', $files) . '".split(","),function(f){tinymce.ScriptLoader.markDone(tinyMCE.baseURL+"/"+f+".js");});';

		// Compress data
		if ($supportsGzip)
			$buffer = gzencode($buffer, 9, FORCE_GZIP);

		// Write cached file
		if ($this->settings["disk_cache"])
			@file_put_contents($cacheFile, $buffer);	

		// Stream contents to client
		echo $buffer;
	}

	/**
	 * Renders a script tag that loads the TinyMCE script.
	 *
	 * @param Array $settings Name/value array with settings for the script tag.
	 * @param Bool  $return   The script tag is return instead of being output if true
	 * @return String the tag is returned if $return is true  
	 */
	public static function renderTag($tagSettings, $return = false) {
		$settings = array_merge(self::$defaultSettings, $tagSettings);

		if (empty($settings["cache_dir"]))
			$settings["cache_dir"] = dirname(__FILE__);

		$scriptSrc = $settings["url"] . "?js=1";

		// Add plugins
		if (isset($settings["plugins"]))
			$scriptSrc .= "&plugins=" . (is_array($settings["plugins"]) ? implode(',', $settings["plugins"]) : $settings["plugins"]);

		// Add themes
		if (isset($settings["themes"]))
			$scriptSrc .= "&themes=" . (is_array($settings["themes"]) ? implode(',', $settings["themes"]) : $settings["themes"]);

		// Add languages
		if (isset($settings["languages"]))
			$scriptSrc .= "&languages=" . (is_array($settings["languages"]) ? implode(',', $settings["languages"]) : $settings["languages"]);

		// Add disk_cache
		if (isset($settings["disk_cache"]))
			$scriptSrc .= "&diskcache=" . ($settings["disk_cache"] === true ? "true" : "false");

		// Add any explicitly specified files if the default settings have been overriden by the tag ones
		/*
		 * Specifying tag files will override (rather than merge with) any site-specific ones set in the 
		 * TinyMCE_Compressor object creation.  Note that since the parameter parser limits content to alphanumeric
		 * only base filenames can be specified.  The file extension is assumed to be ".js" and the directory is
		 * the TinyMCE root directory.  A typical use of this is to include a script which initiates the TinyMCE object. 
		 */
		if (isset($tagSettings["files"]))
			$scriptSrc .= "&files=" .(is_array($settings["files"]) ? implode(',', $settings["files"]) : $settings["files"]);

		// Add src flag
		if (isset($settings["source"]))
			$scriptSrc .= "&src=" . ($settings["source"] === true ? "true" : "false");

		$scriptTag = '<script type="text/javascript" src="' . htmlspecialchars($scriptSrc) . '"></script>';

		if ($return) {
			return $scriptTag;
		} else {
			echo $scriptTag;
		}
	}

	/**
	 * Returns a sanitized query string parameter.
	 *
	 * @param String $name Name of the query string param to get.
	 * @param String $default Default value if the query string item shouldn't exist.
	 * @return String Sanitized query string parameter value.
	 */
	public static function getParam($name, $default = "") {
		if (!isset($_GET[$name]))
			return $default;

		return preg_replace("/[^0-9a-z\-_,]+/i", "", $_GET[$name]); // Sanatize for security, remove anything but 0-9,a-z,-_,
	}

	/**
	 * Parses the specified time format into seconds. Supports formats like 10h, 10d, 10m.
	 *
	 * @param String $time Time format to convert into seconds.
	 * @return Int Number of seconds for the specified format.
	 */
	private function parseTime($time) {
		$multipel = 1;

		// Hours
		if (strpos($time, "h") > 0)
			$multipel = 3600;

		// Days
		if (strpos($time, "d") > 0)
			$multipel = 86400;

		// Months
		if (strpos($time, "m") > 0)
			$multipel = 2592000;

		// Trim string
		return intval($time) * $multipel;
	}

	/**
	 * Returns the contents of the script file if it exists and removes the UTF-8 BOM header if it exists.
	 *
	 * @param String $file File to load.
	 * @return String File contents or empty string if it doesn't exist.
	 */
	private function getFileContents($file) {
		$content = file_get_contents($file);

		// Remove UTF-8 BOM
		if (substr($content, 0, 3) === pack("CCC", 0xef, 0xbb, 0xbf))
			$content = substr($content, 3);

		return $content;
	}
}