<?php
/**
 * RainTPL
 *
 * Realized by Federico Ulfo & maintained by the Rain Team
 * Distributed under GNU/LGPL 3 License
 *
 * @version 2.7.2
 */


/**
 * RainTPL
 */
class RainTPL{

	// -------------------------
	// 	CONFIGURATION
	// -------------------------

		/**
		 * Template directory
		 *
		 * @var string
		 */
		static $tpl_dir = 'tpl/';


		/**
		 * Cache directory
		 *
		 * Is the directory where RainTPL will compile the template and save the cache
		 *
		 * @var string
		 */
		static $cache_dir = 'tmp/';


		/**
		 * Template base URL
		 *
		 * RainTPL will add this URL to the relative paths of element selected in $path_replace_list.
		 *
		 * @var string
		 */
		static $base_url = null;


		/**
		 * Template extension
		 *
		 * @var string
		 */
		static $tpl_ext = "html";


		/**
		 * Should the path be replaced
		 *
		 * Path replace is a cool features that replace all relative paths of images (&lt;img src="..."&gt;), stylesheet (&lt;link href="..."&gt;), script (&lt;script src="..."&gt;) and link (&lt;a href="..."&gt;)
		 * Set true to enable the path replace.
		 *
		 * @var boolean
		 */
		static $path_replace = true;


		/**
		 * You can set what the path_replace method will replace.
		 * Avaible options: a, img, link, script, input
		 *
		 * @var array
		 */
		static $path_replace_list = array( 'a', 'img', 'link', 'script', 'input' );


		/**
		 * You can define in the black list what string are disabled into the template tags
		 *
		 * @var array
		 */
		static $black_list = array( '\$this', 'raintpl::', 'self::', '_SESSION', '_SERVER', '_ENV',  'eval', 'exec', 'unlink', 'rmdir' );


		/**
		 * Check template
		 *
		 * true: checks template update time, if changed it compile them
		 * false: loads the compiled template. Set false if server doesn't have write permission for cache_directory.
		 *
		 * @var bool
		 */
		static $check_template_update = true;


		/**
		 * PHP tags <? ?>
		 *
		 * True: php tags are enabled into the template
		 * False: php tags are disabled into the template and rendered as html
		 *
		 * @var bool
		 */
		static $php_enabled = false;


		/**
		 * Debug mode flag
		 *
		 * True: debug mode is used, syntax errors are displayed directly in template. Execution of script is not terminated.
		 * False: exception is thrown on found error.
		 *
		 * @var bool
		 */
		static $debug = false;

	// -------------------------


	// -------------------------
	// 	RAINTPL VARIABLES
	// -------------------------

		/**
		 * Is the array where RainTPL keep the variables assigned
		 *
		 * @var array
		 */
		public $var = array();

		/**
		 * variables to keep the template directories and info
		 *
		 * @var array
		 */
		protected $tpl = array();		//

		/**
		 * static cache enabled / disabled
		 *
		 * @var bool
		 */
		protected $cache = false;

		/**
		 * identify only one cache
		 *
		 * @var string
		 */
		protected $cache_id = '';

		/**
		 * takes all the config to create the md5 of the file
		 *
		 * @var array the file
		 */
		protected static $config_name_sum = array();

	// -------------------------


	/**
	 * default cache expire time = hour
	 *
	 * @const int
	 */
	const CACHE_EXPIRE_TIME = 3600;


	/**
	 * Assign variable
	 * eg. 	$t->assign('name','mickey');
	 *
	 * @access public
	 * @param  mixed $variable_name Name of template variable or associative array name/value
	 * @param  mixed $value value assigned to this variable. Not set if variable_name is an associative array
	 */
	public function assign( $variable, $value = null ){
		if( is_array( $variable ) )
			$this->var += $variable;
		else
			$this->var[ $variable ] = $value;
	}


	/**
	 * Draw the template
	 * eg. 	$html = $tpl->draw( 'demo', TRUE ); // return template in string
	 * or 	$tpl->draw( $tpl_name ); // echo the template
	 *
	 * @access public
	 * @param  string $tpl_name  template to load
	 * @param  boolean $return_string  true=return a string, false=echo the template
	 * @return string
	 */
	public function draw( $tpl_name, $return_string = false ){

		try {
			// compile the template if necessary and set the template filepath
			$this->check_template( $tpl_name );
		} catch (RainTpl_Exception $e) {
			$output = $this->printDebug($e);
			die($output);
		}

		// Cache is off and, return_string is false
		// Rain just echo the template

		if( !$this->cache && !$return_string ){
			extract( $this->var );
			include $this->tpl['compiled_filename'];
			unset( $this->tpl );
		}


		// cache or return_string are enabled
		// rain get the output buffer to save the output in the cache or to return it as string

		else{

			//----------------------
			// get the output buffer
			//----------------------
				ob_start();
				extract( $this->var );
				include $this->tpl['compiled_filename'];
				$raintpl_contents = ob_get_clean();
			//----------------------


			// save the output in the cache
			if( $this->cache )
				file_put_contents( $this->tpl['cache_filename'], "<?php if(!class_exists('raintpl')){exit;}?>" . $raintpl_contents );

			// free memory
			unset( $this->tpl );

			// return or print the template
			if( $return_string ) return $raintpl_contents; else echo $raintpl_contents;

		}

	}


	/**
	 * If exists a valid cache for this template it returns the cache
	 *
	 * @access public
	 * @param  string $tpl_name Name of template (set the same of draw)
	 * @param  int $expiration_time Set after how many seconds the cache expire and must be regenerated
	 * @param  string $cache_id Suffix to be used when writing file to cache (optional)
	 * @return string it return the HTML or null if the cache must be recreated
	 */
	public function cache( $tpl_name, $expire_time = self::CACHE_EXPIRE_TIME, $cache_id = '' ){

		// set the cache_id
		$this->cache_id = $cache_id;

		if( !$this->check_template( $tpl_name ) && file_exists( $this->tpl['cache_filename'] ) && ( time() - filemtime( $this->tpl['cache_filename'] ) < $expire_time ) )
			return substr( file_get_contents( $this->tpl['cache_filename'] ), 43 );
		else{
			//delete the cache of the selected template
			if (file_exists($this->tpl['cache_filename']))
			unlink($this->tpl['cache_filename'] );
			$this->cache = true;
		}
	}


	/**
	 * Configure the settings of RainTPL
	 *
	 * @access public
	 * @static
	 * @param  array|string $setting array of settings or setting name
	 * @param  mixed $value content to set in the setting (optional)
	 */
	public static function configure( $setting, $value = null ){
		if( is_array( $setting ) )
			foreach( $setting as $key => $value )
				self::configure( $key, $value );
		else if( property_exists( __CLASS__, $setting ) ){
			self::$$setting = $value;
			self::$config_name_sum[ $setting ] = $value; // take trace of all config
		}
	}


	/**
	 * Check if has to compile the template
	 *
	 * @access protected
	 * @param  string $tpl_name template name to check
	 * @throws RainTpl_NotFoundException
	 * @return bool return true if the template has changed
	 */
	protected function check_template( $tpl_name ){

		if( !isset($this->tpl['checked']) ){

			$tpl_basename					   = basename( $tpl_name );														// template basename
			$tpl_basedir						= strpos($tpl_name,"/") ? dirname($tpl_name) . '/' : null;						// template basedirectory
			$tpl_dir							= PATH . self::$tpl_dir . $tpl_basedir;								// template directory
			$this->tpl['tpl_filename']		  = $tpl_dir . $tpl_basename . '.' . self::$tpl_ext;	// template filename
			$temp_compiled_filename			 = PATH . self::$cache_dir . $tpl_basename . "." . md5( $tpl_dir . serialize(self::$config_name_sum));
			$this->tpl['compiled_filename']	 = $temp_compiled_filename . '.rtpl.php';	// cache filename
			$this->tpl['cache_filename']		= $temp_compiled_filename . '.s_' . $this->cache_id . '.rtpl.php';	// static cache filename

			// if the template doesn't exsist throw an error
			if( self::$check_template_update && !file_exists( $this->tpl['tpl_filename'] ) ){
				$e = new RainTpl_NotFoundException( 'Template '. $tpl_basename .' not found!' );
				throw $e->setTemplateFile($this->tpl['tpl_filename']);
			}

			// file doesn't exsist, or the template was updated, Rain will compile the template
			if( !file_exists( $this->tpl['compiled_filename'] ) || ( self::$check_template_update && filemtime($this->tpl['compiled_filename']) < filemtime( $this->tpl['tpl_filename'] ) ) ){
				$this->compileFile( $tpl_basedir, $this->tpl['tpl_filename'], PATH . self::$cache_dir, $this->tpl['compiled_filename'] );
				return true;
			}
			$this->tpl['checked'] = true;
		}
	}


	/**
	 * execute stripslaches() on the xml block. Invoqued by preg_replace_callback function below
	 *
	 * @access protected
	 * @param string $capture
	 * @return string
	 */
	protected function xml_reSubstitution($capture) {
			return "<?php echo '<?xml ".stripslashes($capture[1])." ?>'; ?>";
	}


	/**
	 * Compile and write the compiled template file
	 *
	 * @access protected
	 * @param  string $tpl_basedir
	 * @param  string $tpl_filename
	 * @param  string $cache_dir
	 * @param  string $compiled_filename
	 * @throws RainTpl_Exception
	 * @return void
	 */
	protected function compileFile( $tpl_basedir, $tpl_filename, $cache_dir, $compiled_filename ){

		//read template file
		$this->tpl['source'] = $template_code = file_get_contents( $tpl_filename );

		//xml substitution
		$template_code = preg_replace( "/<\?xml(.*?)\?>/s", "##XML\\1XML##", $template_code );

		//disable php tag
		if( !self::$php_enabled )
			$template_code = str_replace( array("<?","?>"), array("&lt;?","?&gt;"), $template_code );

		//xml re-substitution
		$template_code = preg_replace_callback ( "/##XML(.*?)XML##/s", array($this, 'xml_reSubstitution'), $template_code );

		//compile template
		$template_compiled = "<?php if(!class_exists('raintpl')){exit;}?>" . $this->compileTemplate( $template_code, $tpl_basedir );


		// fix the php-eating-newline-after-closing-tag-problem
		$template_compiled = str_replace( "?>\n", "?>\n\n", $template_compiled );

		// create directories
		if( !is_dir( $cache_dir ) )
			mkdir( $cache_dir, 0755, true );

		if( !is_writable( $cache_dir ) )
			throw new RainTpl_Exception ('Cache directory ' . $cache_dir . ' doesn\'t have write permission. Set write permission or set RAINTPL_CHECK_TEMPLATE_UPDATE to false. More details on http://www.raintpl.com/Documentation/Documentation-for-PHP-developers/Configuration/');

		//write compiled file
		file_put_contents( $compiled_filename, $template_compiled );
	}


	/**
	 * Compile template
	 *
	 * @access protected
	 * @param  string $template_code
	 * @param  string $tpl_basedir
	 * @return string
	 */
	protected function compileTemplate( $template_code, $tpl_basedir ){

		//tag list
		$tag_regexp = array( 'loop'		 => '(\{loop(?: name){0,1}="\${0,1}[^"]*"\})',
							 'loop_close'   => '(\{\/loop\})',
							 'if'		   => '(\{if(?: condition){0,1}="[^"]*"\})',
							 'elseif'	   => '(\{elseif(?: condition){0,1}="[^"]*"\})',
							 'else'		 => '(\{else\})',
							 'if_close'	 => '(\{\/if\})',
							 'function'	 => '(\{function="[^"]*"\})',
							 'noparse'	  => '(\{noparse\})',
							 'noparse_close'=> '(\{\/noparse\})',
							 'ignore'	   => '(\{ignore\}|\{\*)',
							 'ignore_close'	=> '(\{\/ignore\}|\*\})',
							 'include'	  => '(\{include="[^"]*"(?: cache="[^"]*")?\})',
							 'template_info'=> '(\{\$template_info\})',
							 'function'		=> '(\{function="(\w*?)(?:.*?)"\})'
							);

		$tag_regexp = "/" . join( "|", $tag_regexp ) . "/";

		//split the code with the tags regexp
		$template_code = preg_split ( $tag_regexp, $template_code, -1, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY );

		//path replace (src of img, background and href of link)
		$template_code = $this->path_replace( $template_code, $tpl_basedir );

		//compile the code
		$compiled_code = $this->compileCode( $template_code );

		//return the compiled code
		return $compiled_code;

	}


	/**
	 * Compile the code
	 *
	 * @access protected
	 * @param  string $parsed_code
	 * @throws RainTpl_SyntaxException
	 * @return string
	 */
	protected function compileCode( $parsed_code ){

		//variables initialization
		$compiled_code = $open_if = $comment_is_open = $ignore_is_open = null;
		$loop_level = 0;

		//read all parsed code
		while( $html = array_shift( $parsed_code ) ){

			//close ignore tag
			if( !$comment_is_open && ( strpos( $html, '{/ignore}' ) !== FALSE || strpos( $html, '*}' ) !== FALSE ) )
				$ignore_is_open = false;

			//code between tag ignore id deleted
			elseif( $ignore_is_open ){
				//ignore the code
			}

			//close no parse tag
			elseif( strpos( $html, '{/noparse}' ) !== FALSE )
				$comment_is_open = false;

			//code between tag noparse is not compiled
			elseif( $comment_is_open )
				$compiled_code .= $html;

			//ignore
			elseif( strpos( $html, '{ignore}' ) !== FALSE || strpos( $html, '{*' ) !== FALSE )
				$ignore_is_open = true;

			//noparse
			elseif( strpos( $html, '{noparse}' ) !== FALSE )
				$comment_is_open = true;

			//include tag
			elseif( preg_match( '/\{include="([^"]*)"(?: cache="([^"]*)"){0,1}\}/', $html, $code ) ){

				//variables substitution
				$include_var = $this->var_replace( $code[ 1 ], $left_delimiter = null, $right_delimiter = null, $php_left_delimiter = '".' , $php_right_delimiter = '."', $loop_level );

				// if the cache is active
				if( isset($code[ 2 ]) ){

					//dynamic include
					$compiled_code .= '<?php $tpl = new '.get_class($this).';' .
								 'if( $cache = $tpl->cache( $template = basename("'.$include_var.'") ) )' .
								 '	echo $cache;' .
								 'else{' .
								 '	$tpl_dir_temp = self::$tpl_dir;' .
								 '	$tpl->assign( $this->var );' .
									( !$loop_level ? null : '$tpl->assign( "key", $key'.$loop_level.' ); $tpl->assign( "value", $value'.$loop_level.' );' ).
								 '	$tpl->draw( dirname("'.$include_var.'") . ( substr("'.$include_var.'",-1,1) != "/" ? "/" : "" ) . basename("'.$include_var.'") );'.
								 '} ?>';
				}
				else{

					//dynamic include
					$compiled_code .= '<?php $tpl = new '.get_class($this).';' .
									  '$tpl_dir_temp = self::$tpl_dir;' .
									  '$tpl->assign( $this->var );' .
									  ( !$loop_level ? null : '$tpl->assign( "key", $key'.$loop_level.' ); $tpl->assign( "value", $value'.$loop_level.' );' ).
									  '$tpl->draw( dirname("'.$include_var.'") . ( substr("'.$include_var.'",-1,1) != "/" ? "/" : "" ) . basename("'.$include_var.'") );'.
									  '?>';


				}

			}

			//loop
			elseif( preg_match( '/\{loop(?: name){0,1}="\${0,1}([^"]*)"\}/', $html, $code ) ){

				//increase the loop counter
				$loop_level++;

				//replace the variable in the loop
				$var = $this->var_replace( '$' . $code[ 1 ], $tag_left_delimiter=null, $tag_right_delimiter=null, $php_left_delimiter=null, $php_right_delimiter=null, $loop_level-1 );

				//loop variables
				$counter = "\$counter$loop_level";	   // count iteration
				$key = "\$key$loop_level";			   // key
				$value = "\$value$loop_level";		   // value

				//loop code
				$compiled_code .=  "<?php $counter=-1; if( isset($var) && is_array($var) && sizeof($var) ) foreach( $var as $key => $value ){ $counter++; ?>";

			}

			//close loop tag
			elseif( strpos( $html, '{/loop}' ) !== FALSE ) {

				//iterator
				$counter = "\$counter$loop_level";

				//decrease the loop counter
				$loop_level--;

				//close loop code
				$compiled_code .=  "<?php } ?>";

			}

			//if
			elseif( preg_match( '/\{if(?: condition){0,1}="([^"]*)"\}/', $html, $code ) ){

				//increase open if counter (for intendation)
				$open_if++;

				//tag
				$tag = $code[ 0 ];

				//condition attribute
				$condition = $code[ 1 ];

				// check if there's any function disabled by black_list
				$this->function_check( $tag );

				//variable substitution into condition (no delimiter into the condition)
				$parsed_condition = $this->var_replace( $condition, $tag_left_delimiter = null, $tag_right_delimiter = null, $php_left_delimiter = null, $php_right_delimiter = null, $loop_level );

				//if code
				$compiled_code .=   "<?php if( $parsed_condition ){ ?>";

			}

			//elseif
			elseif( preg_match( '/\{elseif(?: condition){0,1}="([^"]*)"\}/', $html, $code ) ){

				//tag
				$tag = $code[ 0 ];

				//condition attribute
				$condition = $code[ 1 ];

				//variable substitution into condition (no delimiter into the condition)
				$parsed_condition = $this->var_replace( $condition, $tag_left_delimiter = null, $tag_right_delimiter = null, $php_left_delimiter = null, $php_right_delimiter = null, $loop_level );

				//elseif code
				$compiled_code .=   "<?php }elseif( $parsed_condition ){ ?>";
			}

			//else
			elseif( strpos( $html, '{else}' ) !== FALSE ) {

				//else code
				$compiled_code .=   '<?php }else{ ?>';

			}

			//close if tag
			elseif( strpos( $html, '{/if}' ) !== FALSE ) {

				//decrease if counter
				$open_if--;

				// close if code
				$compiled_code .=   '<?php } ?>';

			}

			//function
			elseif( preg_match( '/\{function="(\w*)(.*?)"\}/', $html, $code ) ){

				//tag
				$tag = $code[ 0 ];

				//function
				$function = $code[ 1 ];

				// check if there's any function disabled by black_list
				$this->function_check( $tag );

				if( empty( $code[ 2 ] ) )
					$parsed_function = $function . "()";
				else
					// parse the function
					$parsed_function = $function . $this->var_replace( $code[ 2 ], $tag_left_delimiter = null, $tag_right_delimiter = null, $php_left_delimiter = null, $php_right_delimiter = null, $loop_level );

				//if code
				$compiled_code .=   "<?php echo $parsed_function; ?>";
			}

			// show all vars
			elseif ( strpos( $html, '{$template_info}' ) !== FALSE ) {

				//tag
				$tag  = '{$template_info}';

				//if code
				$compiled_code .=   '<?php echo "<pre>"; print_r( $this->var ); echo "</pre>"; ?>';
			}


			//all html code
			else{

				//variables substitution (es. {$title})
				$html = $this->var_replace( $html, $left_delimiter = '\{', $right_delimiter = '\}', $php_left_delimiter = '<?php ', $php_right_delimiter = ';?>', $loop_level, $echo = true );
				//const substitution (es. {#CONST#})
				$html = $this->const_replace( $html, $left_delimiter = '\{', $right_delimiter = '\}', $php_left_delimiter = '<?php ', $php_right_delimiter = ';?>', $loop_level, $echo = true );
				//functions substitution (es. {"string"|functions})
				$compiled_code .= $this->func_replace( $html, $left_delimiter = '\{', $right_delimiter = '\}', $php_left_delimiter = '<?php ', $php_right_delimiter = ';?>', $loop_level, $echo = true );
			}
		}

		if( $open_if > 0 ) {
			$e = new RainTpl_SyntaxException('Error! You need to close an {if} tag in ' . $this->tpl['tpl_filename'] . ' template');
			throw $e->setTemplateFile($this->tpl['tpl_filename']);
		}
		return $compiled_code;
	}


	/**
	 * Reduce a path
	 *
	 * eg. www/library/../filepath//file => www/filepath/file
	 *
	 * @param string $path
	 * @return string
	 */
	protected function reduce_path( $path ){
		$path = str_replace( "://", "@not_replace@", $path );
		$path = str_replace( "//", "/", $path );
		$path = str_replace( "@not_replace@", "://", $path );
		return preg_replace('/\w+\/\.\.\//', '', $path );
	}


	/**
	 * replace the path of image src, link href and a href
	 *
	 * url => template_dir/url
	 * url# => url
	 * http://url => http://url
	 *
	 * @access protected
	 * @param  string $html
	 * @param  string $tpl_basedir
	 * @return string html substitution
	 */
	protected function path_replace( $html, $tpl_basedir ){

		if( self::$path_replace ){

			$tpl_dir = self::$base_url . PATH . self::$tpl_dir . $tpl_basedir;

			// reduce the path
			$path = $this->reduce_path($tpl_dir);

			$exp = $sub = array();

			if( in_array( "img", self::$path_replace_list ) ){
				$exp = array( '/<img(.*?)src=(?:")(http|https)\:\/\/([^"]+?)(?:")/i', '/<img(.*?)src=(?:")([^"]+?)#(?:")/i', '/<img(.*?)src="(.*?)"/', '/<img(.*?)src=(?:\@)([^"]+?)(?:\@)/i' );
				$sub = array( '<img$1src=@$2://$3@', '<img$1src=@$2@', '<img$1src="' . $path . '$2"', '<img$1src="$2"' );
			}

			if( in_array( "script", self::$path_replace_list ) ){
				$exp = array_merge( $exp , array( '/<script(.*?)src=(?:")(http|https)\:\/\/([^"]+?)(?:")/i', '/<script(.*?)src=(?:")([^"]+?)#(?:")/i', '/<script(.*?)src="(.*?)"/', '/<script(.*?)src=(?:\@)([^"]+?)(?:\@)/i' ) );
				$sub = array_merge( $sub , array( '<script$1src=@$2://$3@', '<script$1src=@$2@', '<script$1src="' . $path . '$2"', '<script$1src="$2"' ) );
			}

			if( in_array( "link", self::$path_replace_list ) ){
				$exp = array_merge( $exp , array( '/<link(.*?)href=(?:")(http|https)\:\/\/([^"]+?)(?:")/i', '/<link(.*?)href=(?:")([^"]+?)#(?:")/i', '/<link(.*?)href="(.*?)"/', '/<link(.*?)href=(?:\@)([^"]+?)(?:\@)/i' ) );
				$sub = array_merge( $sub , array( '<link$1href=@$2://$3@', '<link$1href=@$2@' , '<link$1href="' . $path . '$2"', '<link$1href="$2"' ) );
			}

			if( in_array( "a", self::$path_replace_list ) ){
				$exp = array_merge( $exp , array( '/<a(.*?)href=(?:")(http\:\/\/|https\:\/\/|javascript:)([^"]+?)(?:")/i', '/<a(.*?)href="(.*?)"/', '/<a(.*?)href=(?:\@)([^"]+?)(?:\@)/i'  ) );
				$sub = array_merge( $sub , array( '<a$1href=@$2$3@', '<a$1href="' . self::$base_url . '$2"', '<a$1href="$2"' ) );
			}

			if( in_array( "input", self::$path_replace_list ) ){
				$exp = array_merge( $exp , array( '/<input(.*?)src=(?:")(http|https)\:\/\/([^"]+?)(?:")/i', '/<input(.*?)src=(?:")([^"]+?)#(?:")/i', '/<input(.*?)src="(.*?)"/', '/<input(.*?)src=(?:\@)([^"]+?)(?:\@)/i' ) );
				$sub = array_merge( $sub , array( '<input$1src=@$2://$3@', '<input$1src=@$2@', '<input$1src="' . $path . '$2"', '<input$1src="$2"' ) );
			}

			return preg_replace( $exp, $sub, $html );

		}
		else
			return $html;

	}


	/**
	 * replace constants
	 *
	 * @access public
	 * @param  string $html
	 * @param  string $tag_left_delimiter
	 * @param  string $tag_right_delimiter
	 * @param  string $php_left_delimiter (optional)
	 * @param  string $php_right_delimiter (optional)
	 * @param  string $loop_level (optional)
	 * @param  string $echo (optional)
	 * @return string
	 */
	public function const_replace( $html, $tag_left_delimiter, $tag_right_delimiter, $php_left_delimiter = null, $php_right_delimiter = null, $loop_level = null, $echo = null ){
		// const
		return preg_replace( '/\{\#(\w+)\#{0,1}\}/', $php_left_delimiter . ( $echo ? " echo " : null ) . '\\1' . $php_right_delimiter, $html );
	}


	/**
	 * replace functions/modifiers on constants and strings
	 *
	 * @access public
	 * @param  string $html
	 * @param  string $tag_left_delimiter
	 * @param  string $tag_right_delimiter
	 * @param  string $php_left_delimiter (optional)
	 * @param  string $php_right_delimiter (optional)
	 * @param  string $loop_level (optional)
	 * @param  string $echo (optional)
	 * @return string
	 */
	public function func_replace( $html, $tag_left_delimiter, $tag_right_delimiter, $php_left_delimiter = null, $php_right_delimiter = null, $loop_level = null, $echo = null ){

		preg_match_all( '/' . '\{\#{0,1}(\"{0,1}.*?\"{0,1})(\|\w.*?)\#{0,1}\}' . '/', $html, $matches );

		for( $i=0, $n=count($matches[0]); $i<$n; $i++ ){

			//complete tag ex: {$news.title|substr:0,100}
			$tag = $matches[ 0 ][ $i ];

			//variable name ex: news.title
			$var = $matches[ 1 ][ $i ];

			//function and parameters associate to the variable ex: substr:0,100
			$extra_var = $matches[ 2 ][ $i ];

			// check if there's any function disabled by black_list
			$this->function_check( $tag );

			$extra_var = $this->var_replace( $extra_var, null, null, null, null, $loop_level );


			// check if there's an operator = in the variable tags, if there's this is an initialization so it will not output any value
			$is_init_variable = preg_match( "/^(\s*?)\=[^=](.*?)$/", $extra_var );

			//function associate to variable
			$function_var = ( $extra_var and $extra_var[0] == '|') ? substr( $extra_var, 1 ) : null;

			//variable path split array (ex. $news.title o $news[title]) or object (ex. $news->title)
			$temp = preg_split( "/\.|\[|\-\>/", $var );

			//variable name
			$var_name = $temp[ 0 ];

			//variable path
			$variable_path = substr( $var, strlen( $var_name ) );

			//parentesis transform [ e ] in [" e in "]
			$variable_path = str_replace( '[', '["', $variable_path );
			$variable_path = str_replace( ']', '"]', $variable_path );

			//transform .$variable in ["$variable"]
			$variable_path = preg_replace('/\.\$(\w+)/', '["$\\1"]', $variable_path );

			//transform [variable] in ["variable"]
			$variable_path = preg_replace('/\.(\w+)/', '["\\1"]', $variable_path );

			//if there's a function
			if( $function_var ){

				// check if there's a function or a static method and separate, function by parameters
				$function_var = str_replace("::", "@double_dot@", $function_var );

				// get the position of the first :
				if( $dot_position = strpos( $function_var, ":" ) ){

					// get the function and the parameters
					$function = substr( $function_var, 0, $dot_position );
					$params = substr( $function_var, $dot_position+1 );

				}
				else{

					//get the function
					$function = str_replace( "@double_dot@", "::", $function_var );
					$params = null;

				}

				// replace back the @double_dot@ with ::
				$function = str_replace( "@double_dot@", "::", $function );
				$params = str_replace( "@double_dot@", "::", $params );


			}
			else
				$function = $params = null;

			$php_var = $var_name . $variable_path;

			// compile the variable for php
			if( isset( $function ) ){
				if( $php_var )
					$php_var = $php_left_delimiter . ( !$is_init_variable && $echo ? 'echo ' : null ) . ( $params ? "( $function( $php_var, $params ) )" : "$function( $php_var )" ) . $php_right_delimiter;
				else
					$php_var = $php_left_delimiter . ( !$is_init_variable && $echo ? 'echo ' : null ) . ( $params ? "( $function( $params ) )" : "$function()" ) . $php_right_delimiter;
			}
			else
				$php_var = $php_left_delimiter . ( !$is_init_variable && $echo ? 'echo ' : null ) . $php_var . $extra_var . $php_right_delimiter;

			$html = str_replace( $tag, $php_var, $html );

		}

		return $html;

	}


	/**
	 * replace variables
	 *
	 * @access public
	 * @param  string $html
	 * @param  string $tag_left_delimiter
	 * @param  string $tag_right_delimiter
	 * @param  string $php_left_delimiter (optional)
	 * @param  string $php_right_delimiter (optional)
	 * @param  string $loop_level (optional)
	 * @param  string $echo (optional)
	 * @return string
	 */
	public function var_replace( $html, $tag_left_delimiter, $tag_right_delimiter, $php_left_delimiter = null, $php_right_delimiter = null, $loop_level = null, $echo = null ){

		//all variables
		if( preg_match_all( '/' . $tag_left_delimiter . '\$(\w+(?:\.\${0,1}[A-Za-z0-9_]+)*(?:(?:\[\${0,1}[A-Za-z0-9_]+\])|(?:\-\>\${0,1}[A-Za-z0-9_]+))*)(.*?)' . $tag_right_delimiter . '/', $html, $matches ) ){

			for( $parsed=array(), $i=0, $n=count($matches[0]); $i<$n; $i++ )
				$parsed[$matches[0][$i]] = array('var'=>$matches[1][$i],'extra_var'=>$matches[2][$i]);

			foreach( $parsed as $tag => $array ){

				//variable name ex: news.title
				$var = $array['var'];

				//function and parameters associate to the variable ex: substr:0,100
				$extra_var = $array['extra_var'];

				// check if there's any function disabled by black_list
				$this->function_check( $tag );

				$extra_var = $this->var_replace( $extra_var, null, null, null, null, $loop_level );

				// check if there's an operator = in the variable tags, if there's this is an initialization so it will not output any value
				$is_init_variable = preg_match( "/^[a-z_A-Z\.\[\](\-\>)]*=[^=]*$/", $extra_var );

				//function associate to variable
				$function_var = ( $extra_var and $extra_var[0] == '|') ? substr( $extra_var, 1 ) : null;

				//variable path split array (ex. $news.title o $news[title]) or object (ex. $news->title)
				$temp = preg_split( "/\.|\[|\-\>/", $var );

				//variable name
				$var_name = $temp[ 0 ];

				//variable path
				$variable_path = substr( $var, strlen( $var_name ) );

				//parentesis transform [ e ] in [" e in "]
				$variable_path = str_replace( '[', '["', $variable_path );
				$variable_path = str_replace( ']', '"]', $variable_path );

				//transform .$variable in ["$variable"] and .variable in ["variable"]
				$variable_path = preg_replace('/\.(\${0,1}\w+)/', '["\\1"]', $variable_path );

				// if is an assignment also assign the variable to $this->var['value']
				if( $is_init_variable )
					$extra_var = "=\$this->var['{$var_name}']{$variable_path}" . $extra_var;


				//if there's a function
				if( $function_var ){

					// check if there's a function or a static method and separate, function by parameters
					$function_var = str_replace("::", "@double_dot@", $function_var );


					// get the position of the first :
					if( $dot_position = strpos( $function_var, ":" ) ){

						// get the function and the parameters
						$function = substr( $function_var, 0, $dot_position );
						$params = substr( $function_var, $dot_position+1 );

					}
					else{

						//get the function
						$function = str_replace( "@double_dot@", "::", $function_var );
						$params = null;

					}

					// replace back the @double_dot@ with ::
					$function = str_replace( "@double_dot@", "::", $function );
					$params = str_replace( "@double_dot@", "::", $params );
				}
				else
					$function = $params = null;

				//if it is inside a loop
				if( $loop_level ){
					//verify the variable name
					if( $var_name == 'key' )
							$php_var = '$key' . $loop_level;
					elseif( $var_name == 'value' )
							$php_var = '$value' . $loop_level . $variable_path;
					elseif( $var_name == 'counter' )
							$php_var = '$counter' . $loop_level;
					else
							$php_var = '$' . $var_name . $variable_path;
				}else
					$php_var = '$' . $var_name . $variable_path;

				// compile the variable for php
				if( isset( $function ) )
					$php_var = $php_left_delimiter . ( !$is_init_variable && $echo ? 'echo ' : null ) . ( $params ? "( $function( $php_var, $params ) )" : "$function( $php_var )" ) . $php_right_delimiter;
				else
					$php_var = $php_left_delimiter . ( !$is_init_variable && $echo ? 'echo ' : null ) . $php_var . $extra_var . $php_right_delimiter;

				$html = str_replace( $tag, $php_var, $html );


			}
		}

		return $html;
	}


	/**
	 * Check if function is in black list (sandbox)
	 *
	 * @access protected
	 * @param  string $code
	 * @throws RainTpl_SyntaxException
	 * @return void
	 */
	protected function function_check( $code ){

		$preg = '#(\W|\s)' . implode( '(\W|\s)|(\W|\s)', self::$black_list ) . '(\W|\s)#';

		// check if the function is in the black list (or not in white list)
		if( count(self::$black_list) && preg_match( $preg, $code, $match ) ){

			// find the line of the error
			$line = 0;
			$rows=explode("\n",$this->tpl['source']);
			while( !strpos($rows[$line],$code) )
				$line++;

			// stop the execution of the script
			$e = new RainTpl_SyntaxException('Unallowed syntax in ' . $this->tpl['tpl_filename'] . ' template');
			throw $e->setTemplateFile($this->tpl['tpl_filename'])
				->setTag($code)
				->setTemplateLine($line);
		}

	}


	/**
	 * Prints debug info about exception or passes it further if debug is disabled.
	 *
	 * @access protected
	 * @param  RainTpl_Exception $e
	 * @return string
	 */
	protected function printDebug(RainTpl_Exception $e){
		if (!self::$debug) {
			throw $e;
		}
		$output = sprintf('<h2>Exception: %s</h2><h3>%s</h3><p>template: %s</p>',
			get_class($e),
			$e->getMessage(),
			$e->getTemplateFile()
		);
		if ($e instanceof RainTpl_SyntaxException) {
			if (null !== $e->getTemplateLine()) {
				$output .= '<p>line: ' . $e->getTemplateLine() . '</p>';
			}
			if (null !== $e->getTag()) {
				$output .= '<p>in tag: ' . htmlspecialchars($e->getTag()) . '</p>';
			}
			if (null !== $e->getTemplateLine() && null !== $e->getTag()) {
				$rows=explode("\n",  htmlspecialchars($this->tpl['source']));
				$rows[$e->getTemplateLine()] = '<font color=red>' . $rows[$e->getTemplateLine()] . '</font>';
				$output .= '<h3>template code</h3>' . implode('<br />', $rows) . '</pre>';
			}
		}
		$output .= sprintf('<h3>trace</h3><p>In %s on line %d</p><pre>%s</pre>',
			$e->getFile(), $e->getLine(),
			nl2br(htmlspecialchars($e->getTraceAsString()))
		);
		return $output;
	}
}


/**
 * Basic Rain tpl exception.
 */
class RainTpl_Exception extends Exception{
	/**
	 * Path of template file with error.
	 */
	protected $templateFile = '';

	/**
	 * Returns path of template file with error.
	 *
	 * @return string
	 */
	public function getTemplateFile()
	{
		return $this->templateFile;
	}

	/**
	 * Sets path of template file with error.
	 *
	 * @param string $templateFile
	 * @return RainTpl_Exception
	 */
	public function setTemplateFile($templateFile)
	{
		$this->templateFile = (string) $templateFile;
		return $this;
	}
}


/**
 * Exception thrown when template file does not exists.
 */
class RainTpl_NotFoundException extends RainTpl_Exception{
}

/**
 * Exception thrown when syntax error occurs.
 */
class RainTpl_SyntaxException extends RainTpl_Exception{
	/**
	 * Line in template file where error has occured.
	 *
	 * @var int | null
	 */
	protected $templateLine = null;

	/**
	 * Tag which caused an error.
	 *
	 * @var string | null
	 */
	protected $tag = null;

	/**
	 * Returns line in template file where error has occured
	 * or null if line is not defined.
	 *
	 * @return int | null
	 */
	public function getTemplateLine()
	{
		return $this->templateLine;
	}

	/**
	 * Sets  line in template file where error has occured.
	 *
	 * @param int $templateLine
	 * @return RainTpl_SyntaxException
	 */
	public function setTemplateLine($templateLine)
	{
		$this->templateLine = (int) $templateLine;
		return $this;
	}

	/**
	 * Returns tag which caused an error.
	 *
	 * @return string
	 */
	public function getTag()
	{
		return $this->tag;
	}

	/**
	 * Sets tag which caused an error.
	 *
	 * @param string $tag
	 * @return RainTpl_SyntaxException
	 */
	public function setTag($tag)
	{
		$this->tag = (string) $tag;
		return $this;
	}
}

// -- end