/libs/Nette/Templating/DefaultHelpers.php

<?php



/**

 * This file is part of the Nette Framework (http://nette.org)

 *

 * Copyright (c) 2004, 2011 David Grudl (http://davidgrudl.com)

 *

 * For the full copyright and license information, please view

 * the file license.txt that was distributed with this source code.

 * @package Nette\Templates
 */







/**

 * Standard template run-time helpers shipped with Nette Framework (http://nette.org)

 *

 * @author     David Grudl

 */

final class NTemplateHelpers

{



	/** @var string default date format */

	public static $dateFormat = '%x';



	/**

	 * Static class - cannot be instantiated.

	 */

	final public function __construct()

	{

		throw new LogicException("Cannot instantiate static class " . get_class($this));

	}







	/**

	 * Try to load the requested helper.

	 * @param  string  helper name

	 * @return callback

	 */

	public static function loader($helper)

	{

		$callback = callback('NTemplateHelpers', $helper);

		if ($callback->isCallable()) {

			return $callback;

		}

		$callback = callback('NString', $helper);

		if ($callback->isCallable()) {

			return $callback;

		}

	}







	/**

	 * Escapes string for use inside HTML template.

	 * @param  mixed  UTF-8 encoding or 8-bit

	 * @return string

	 */

	public static function escapeHtml($s)

	{

		if (is_object($s) && ($s instanceof ITemplate || $s instanceof NHtml || $s instanceof NForm)) {

			return $s->__toString(TRUE);

		}

		return htmlSpecialChars($s, ENT_QUOTES);

	}







	/**

	 * Escapes string for use inside HTML comments.

	 * @param  mixed  UTF-8 encoding or 8-bit

	 * @return string

	 */

	public static function escapeHtmlComment($s)

	{

		// -- has special meaning in different browsers

		return str_replace('--', '--><!-- ', $s); // HTML tags have no meaning inside comments

	}







	/**

	 * Escapes string for use inside XML 1.0 template.

	 * @param  string UTF-8 encoding or 8-bit

	 * @return string

	 */

	public static function escapeXML($s)

	{

		// XML 1.0: \x09 \x0A \x0D and C1 allowed directly, C0 forbidden

		// XML 1.1: \x00 forbidden directly and as a character reference,

		//   \x09 \x0A \x0D \x85 allowed directly, C0, C1 and \x7F allowed as character references

		return htmlSpecialChars(preg_replace('#[\x00-\x08\x0B\x0C\x0E-\x1F]+#', '', $s), ENT_QUOTES);

	}







	/**

	 * Escapes string for use inside CSS template.

	 * @param  string UTF-8 encoding or 8-bit

	 * @return string

	 */

	public static function escapeCss($s)

	{

		// http://www.w3.org/TR/2006/WD-CSS21-20060411/syndata.html#q6

		return addcslashes($s, "\x00..\x1F!\"#$%&'()*+,./:;<=>?@[\\]^`{|}~");

	}







	/**

	 * Escapes string for use inside HTML style attribute.

	 * @param  string UTF-8 encoding or 8-bit

	 * @return string

	 */

	public static function escapeHtmlCss($s)

	{

		return htmlSpecialChars(self::escapeCss($s), ENT_QUOTES);

	}







	/**

	 * Escapes string for use inside JavaScript template.

	 * @param  mixed  UTF-8 encoding

	 * @return string

	 */

	public static function escapeJs($s)

	{

		if (is_object($s) && ($s instanceof ITemplate || $s instanceof NHtml || $s instanceof NForm)) {

			$s = $s->__toString(TRUE);

		}

		return str_replace(']]>', ']]\x3E', NJson::encode($s));

	}







	/**

	 * Escapes string for use inside HTML JavaScript attribute.

	 * @param  mixed  UTF-8 encoding

	 * @return string

	 */

	public static function escapeHtmlJs($s)

	{

		return htmlSpecialChars(self::escapeJs($s), ENT_QUOTES);

	}







	/**

	 * Replaces all repeated white spaces with a single space.

	 * @param  string UTF-8 encoding or 8-bit

	 * @return string

	 */

	public static function strip($s)

	{

		return NString::replace(

			$s,

			'#(</textarea|</pre|</script|^).*?(?=<textarea|<pre|<script|$)#si',

			callback(create_function('$m', '

				return trim(preg_replace("#[ \\t\\r\\n]+#", " ", $m[0]));

			')));

	}







	/**

	 * Indents the HTML content from the left.

	 * @param  string UTF-8 encoding or 8-bit

	 * @param  int

	 * @param  string

	 * @return string

	 */

	public static function indent($s, $level = 1, $chars = "\t")

	{

		if ($level >= 1) {

			$s = NString::replace($s, '#<(textarea|pre).*?</\\1#si', callback(create_function('$m', '

				return strtr($m[0], " \\t\\r\\n", "\\x1F\\x1E\\x1D\\x1A");

			')));

			$s = NString::indent($s, $level, $chars);

			$s = strtr($s, "\x1F\x1E\x1D\x1A", " \t\r\n");

		}

		return $s;

	}







	/**

	 * Date/time formatting.

	 * @param  string|int|DateTime

	 * @param  string

	 * @return string

	 */

	public static function date($time, $format = NULL)

	{

		if ($time == NULL) { // intentionally ==

			return NULL;

		}



		if (!isset($format)) {

			$format = self::$dateFormat;

		}



		$time = DateTime53::from($time);

		return strpos($format, '%') === FALSE

			? $time->format($format) // formats using date()

			: strftime($format, $time->format('U')); // formats according to locales

	}







	/**

	 * Converts to human readable file size.

	 * @param  int

	 * @param  int

	 * @return string

	 */

	public static function bytes($bytes, $precision = 2)

	{

		$bytes = round($bytes);

		$units = array('B', 'kB', 'MB', 'GB', 'TB', 'PB');

		foreach ($units as $unit) {

			if (abs($bytes) < 1024 || $unit === end($units)) break;

			$bytes = $bytes / 1024;

		}

		return round($bytes, $precision) . ' ' . $unit;

	}







	/**

	 * Returns array of string length.

	 * @param  mixed

	 * @return int

	 */

	public static function length($var)

	{

		return is_string($var) ? NString::length($var) : count($var);

	}







	/**

	 * Performs a search and replace.

	 * @param  string

	 * @param  string

	 * @param  string

	 * @return string

	 */

	public static function replace($subject, $search, $replacement = '')

	{

		return str_replace($search, $replacement, $subject);

	}







	/**

	 * The data: URI generator.

	 * @param  string

	 * @param  string

	 * @return string

	 */

	public static function dataStream($data, $type = NULL)

	{

		if ($type === NULL) {

			$type = NMimeTypeDetector::fromString($data, NULL);

		}

		return 'data:' . ($type ? "$type;" : '') . 'base64,' . base64_encode($data);

	}







	/**

	 * /dev/null.

	 * @param  mixed

	 * @return string

	 */

	public static function null($value)

	{

		return '';

	}



}