/**

*

* @package phpBB3

* @version $Id: functions_template.php 8813 2008-09-04 11:52:01Z aptx $

* @copyright (c) 2005 phpBB Group, sections (c) 2001 ispi of Lincoln Inc

* @license http://opensource.org/licenses/gpl-license.php GNU Public License

*

*/

/**

* @ignore

*/

if (!defined('IN_PHPBB'))

{

	exit;

}

/**

* Extension of template class - Functions needed for compiling templates only.

*

* psoTFX, phpBB Development Team - Completion of file caching, decompilation

* routines and implementation of conditionals/keywords and associated changes

*

* The interface was inspired by PHPLib templates,  and the template file (formats are

* quite similar)

*

* The keyword/conditional implementation is currently based on sections of code from

* the Smarty templating engine (c) 2001 ispi of Lincoln, Inc. which is released

* (on its own and in whole) under the LGPL. Section 3 of the LGPL states that any code

* derived from an LGPL application may be relicenced under the GPL, this applies

* to this source

*

* DEFINE directive inspired by a request by Cyberalien

*

* @package phpBB3

*/

class template_compile

{

	var $template;

	// Various storage arrays

	var $block_names = array();

	var $block_else_level = array();

	/**

	* constuctor

	*/

	function template_compile(&$template)

	{

		$this->template = &$template;

	}

	/**

	* Load template source from file

	* @access private

	*/

	function _tpl_load_file($handle, $store_in_db = false)

	{

		// Try and open template for read

		if (!file_exists($this->template->files[$handle]))

		{

			trigger_error("template->_tpl_load_file(): File {$this->template->files[$handle]} does not exist or is empty", E_USER_ERROR);

		}

		$this->template->compiled_code[$handle] = $this->compile(trim(@file_get_contents($this->template->files[$handle])));

		// Actually compile the code now.

		$this->compile_write($handle, $this->template->compiled_code[$handle]);

		// Store in database if required...

		if ($store_in_db)

		{

			global $db, $user;

			$sql_ary = array(

				'template_id'			=> $this->template->files_template[$handle],

				'template_filename'		=> $this->template->filename[$handle],

				'template_included'		=> '',

				'template_mtime'		=> time(),

				'template_data'			=> trim(@file_get_contents($this->template->files[$handle])),

			);

			$sql = 'INSERT INTO ' . STYLES_TEMPLATE_DATA_TABLE . ' ' . $db->sql_build_array('INSERT', $sql_ary);

			$db->sql_query($sql);

		}

	}

	/**

	* Remove any PHP tags that do not belong, these regular expressions are derived from

	* the ones that exist in zend_language_scanner.l

	* @access private

	*/

	function remove_php_tags(&$code)

	{

		// This matches the information gathered from the internal PHP lexer

		$match = array(

			'#<([\?%])=?.*?\1>#s',

			'#<script\s+language\s*=\s*(["\']?)php\1\s*>.*?</script\s*>#s',

			'#<\?php(?:\r\n?|[ \n\t]).*?\?>#s'

		);

		$code = preg_replace($match, '', $code);

	}

	/**

	* The all seeing all doing compile method. Parts are inspired by or directly from Smarty

	* @access private

	*/

	function compile($code, $no_echo = false, $echo_var = '')

	{

		global $config;

		if ($echo_var)

		{

			global $$echo_var;

		}

		// Remove any "loose" php ... we want to give admins the ability

		// to switch on/off PHP for a given template. Allowing unchecked

		// php is a no-no. There is a potential issue here in that non-php

		// content may be removed ... however designers should use entities

		// if they wish to display < and >

		$this->remove_php_tags($code);

		// Pull out all block/statement level elements and separate plain text

		preg_match_all('#(.*?)#s', $code, $matches);

		$php_blocks = $matches[1];

		$code = preg_replace('#.*?#s', '', $code);

		preg_match_all('##', $code, $matches);

		$include_blocks = $matches[1];

		$code = preg_replace('##', '', $code);

		preg_match_all('##', $code, $matches);

		$includephp_blocks = $matches[1];

		$code = preg_replace('##', '', $code);

		preg_match_all('##', $code, $blocks, PREG_SET_ORDER);

		$text_blocks = preg_split('##', $code);

		for ($i = 0, $j = sizeof($text_blocks); $i < $j; $i++)

		{

			$this->compile_var_tags($text_blocks[$i]);

		}

		$compile_blocks = array();

		for ($curr_tb = 0, $tb_size = sizeof($blocks); $curr_tb < $tb_size; $curr_tb++)

		{

			$block_val = &$blocks[$curr_tb];

			switch ($block_val[1])

			{

				case 'BEGIN':

					$this->block_else_level[] = false;

					$compile_blocks[] = 'compile_tag_block($block_val[2]) . ' ?>';

				break;

				case 'BEGINELSE':

					$this->block_else_level[sizeof($this->block_else_level) - 1] = true;

					$compile_blocks[] = '';

				break;

				case 'END':

					array_pop($this->block_names);

					$compile_blocks[] = 'block_else_level)) ? '}' : '}}') . ' ?>';

				break;

				case 'IF':

					$compile_blocks[] = 'compile_tag_if($block_val[2], false) . ' ?>';

				break;

				case 'ELSE':

					$compile_blocks[] = '';

				break;

				case 'ELSEIF':

					$compile_blocks[] = 'compile_tag_if($block_val[2], true) . ' ?>';

				break;

				case 'ENDIF':

					$compile_blocks[] = '';

				break;

				case 'DEFINE':

					$compile_blocks[] = 'compile_tag_define($block_val[2], true) . ' ?>';

				break;

				case 'UNDEFINE':

					$compile_blocks[] = 'compile_tag_define($block_val[2], false) . ' ?>';

				break;

				case 'INCLUDE':

					$temp = array_shift($include_blocks);

					$compile_blocks[] = 'compile_tag_include($temp) . ' ?>';

					$this->template->_tpl_include($temp, false);

				break;

				case 'INCLUDEPHP':

					$compile_blocks[] = ($config['tpl_allow_php']) ? 'compile_tag_include_php(array_shift($includephp_blocks)) . ' ?>' : '';

				break;

				case 'PHP':

					$compile_blocks[] = ($config['tpl_allow_php']) ? '' : '';

				break;

				default:

					$this->compile_var_tags($block_val[0]);

					$trim_check = trim($block_val[0]);

					$compile_blocks[] = (!$no_echo) ? ((!empty($trim_check)) ? $block_val[0] : '') : ((!empty($trim_check)) ? $block_val[0] : '');

				break;

			}

		}

		$template_php = '';

		for ($i = 0, $size = sizeof($text_blocks); $i < $size; $i++)

		{

			$trim_check_text = trim($text_blocks[$i]);

			$template_php .= (!$no_echo) ? (($trim_check_text != '') ? $text_blocks[$i] : '') . ((isset($compile_blocks[$i])) ? $compile_blocks[$i] : '') : (($trim_check_text != '') ? $text_blocks[$i] : '') . ((isset($compile_blocks[$i])) ? $compile_blocks[$i] : '');

		}

		// There will be a number of occasions where we switch into and out of

		// PHP mode instantaneously. Rather than "burden" the parser with this

		// we'll strip out such occurences, minimising such switching

		$template_php = str_replace(' ?>

		return (!$no_echo) ? $template_php : "\$$echo_var .= '" . $template_php . "'";

	}

	/**

	* Compile variables

	* @access private

	*/

	function compile_var_tags(&$text_blocks)

	{

		// change template varrefs into PHP varrefs

		$varrefs = array();

		// This one will handle varrefs WITH namespaces

		preg_match_all('#\{((?:[a-z0-9\-_]+\.)+)(\$)?([A-Z0-9\-_]+)\}#', $text_blocks, $varrefs, PREG_SET_ORDER);

		foreach ($varrefs as $var_val)

		{

			$namespace = $var_val[1];

			$varname = $var_val[3];

			$new = $this->generate_block_varref($namespace, $varname, true, $var_val[2]);

			$text_blocks = str_replace($var_val[0], $new, $text_blocks);

		}

		// This will handle the remaining root-level varrefs

		// transform vars prefixed by L_ into their language variable pendant if nothing is set within the tpldata array

		if (strpos($text_blocks, '{L_') !== false)

		{

			$text_blocks = preg_replace('#\{L_([a-z0-9\-_]*)\}#is', "_rootref['L_\\1'])) ? \$this->_rootref['L_\\1'] : ((isset(\$user->lang['\\1'])) ? \$user->lang['\\1'] : '{ \\1 }')); ?>", $text_blocks);

		}

		// Handle addslashed language variables prefixed with LA_

		// If a template variable already exist, it will be used in favor of it...

		if (strpos($text_blocks, '{LA_') !== false)

		{

			$text_blocks = preg_replace('#\{LA_([a-z0-9\-_]*)\}#is', "_rootref['LA_\\1'])) ? \$this->_rootref['LA_\\1'] : ((isset(\$this->_rootref['L_\\1'])) ? addslashes(\$this->_rootref['L_\\1']) : ((isset(\$user->lang['\\1'])) ? addslashes(\$user->lang['\\1']) : '{ \\1 }'))); ?>", $text_blocks);

		}

		// Handle remaining varrefs

		$text_blocks = preg_replace('#\{([a-z0-9\-_]+)\}#is', "_rootref['\\1'])) ? \$this->_rootref['\\1'] : ''; ?>", $text_blocks);

		$text_blocks = preg_replace('#\{\$([a-z0-9\-_]+)\}#is', "_tpldata['DEFINE']['.']['\\1'])) ? \$this->_tpldata['DEFINE']['.']['\\1'] : ''; ?>", $text_blocks);

		return;

	}

	/**

	* Compile blocks

	* @access private

	*/

	function compile_tag_block($tag_args)

	{

		$no_nesting = false;

		// Is the designer wanting to call another loop in a loop?

		if (strpos($tag_args, '!') === 0)

		{

			// Count the number if ! occurrences (not allowed in vars)

			$no_nesting = substr_count($tag_args, '!');

			$tag_args = substr($tag_args, $no_nesting);

		}

		// Allow for control of looping (indexes start from zero):

		// foo(2)    : Will start the loop on the 3rd entry

		// foo(-2)   : Will start the loop two entries from the end

		// foo(3,4)  : Will start the loop on the fourth entry and end it on the fifth

		// foo(3,-4) : Will start the loop on the fourth entry and end it four from last

		if (preg_match('#^([^()]*)\(([\-\d]+)(?:,([\-\d]+))?\)$#', $tag_args, $match))

		{

			$tag_args = $match[1];

			if ($match[2] < 0)

			{

				$loop_start = '($_' . $tag_args . '_count ' . $match[2] . ' < 0 ? 0 : $_' . $tag_args . '_count ' . $match[2] . ')';

			}

			else

			{

				$loop_start = '($_' . $tag_args . '_count < ' . $match[2] . ' ? $_' . $tag_args . '_count : ' . $match[2] . ')';

			}

			if (strlen($match[3]) < 1 || $match[3] == -1)

			{

				$loop_end = '$_' . $tag_args . '_count';

			}

			else if ($match[3] >= 0)

			{

				$loop_end = '(' . ($match[3] + 1) . ' > $_' . $tag_args . '_count ? $_' . $tag_args . '_count : ' . ($match[3] + 1) . ')';

			}

			else //if ($match[3] < -1)

			{

				$loop_end = '$_' . $tag_args . '_count' . ($match[3] + 1);

			}

		}

		else

		{

			$loop_start = 0;

			$loop_end = '$_' . $tag_args . '_count';

		}

		$tag_template_php = '';

		array_push($this->block_names, $tag_args);

		if ($no_nesting !== false)

		{

			// We need to implode $no_nesting times from the end...

			$block = array_slice($this->block_names, -$no_nesting);

		}

		else

		{

			$block = $this->block_names;

		}

		if (sizeof($block) < 2)

		{

			// Block is not nested.

			$tag_template_php = '$_' . $tag_args . "_count = (isset(\$this->_tpldata['$tag_args'])) ? sizeof(\$this->_tpldata['$tag_args']) : 0;";

			$varref = "\$this->_tpldata['$tag_args']";

		}

		else

		{

			// This block is nested.

			// Generate a namespace string for this block.

			$namespace = implode('.', $block);

			// Get a reference to the data array for this block that depends on the

			// current indices of all parent blocks.

			$varref = $this->generate_block_data_ref($namespace, false);

			// Create the for loop code to iterate over this block.

			$tag_template_php = '$_' . $tag_args . '_count = (isset(' . $varref . ')) ? sizeof(' . $varref . ') : 0;';

		}

		$tag_template_php .= 'if ($_' . $tag_args . '_count) {';

		/**

		* The following uses foreach for iteration instead of a for loop, foreach is faster but requires PHP to make a copy of the contents of the array which uses more memory

		* 

		*	if (!$offset)

		*	{

		*		$tag_template_php .= 'foreach (' . $varref . ' as $_' . $tag_args . '_i => $_' . $tag_args . '_val){';

		*	}

		* 

		*/

		$tag_template_php .= 'for ($_' . $tag_args . '_i = ' . $loop_start . '; $_' . $tag_args . '_i < ' . $loop_end . '; ++$_' . $tag_args . '_i){';

		$tag_template_php .= '$_'. $tag_args . '_val = &' . $varref . '[$_'. $tag_args. '_i];';

		return $tag_template_php;

	}

	/**

	* Compile IF tags - much of this is from Smarty with

	* some adaptions for our block level methods

	* @access private

	*/

	function compile_tag_if($tag_args, $elseif)

	{

		// Tokenize args for 'if' tag.

		preg_match_all('/(?:

			"[^"\\\\]*(?:\\\\.[^"\\\\]*)*"         |

			\'[^\'\\\\]*(?:\\\\.[^\'\\\\]*)*\'     |

			[(),]                                  |

			[^\s(),]+)/x', $tag_args, $match);

		$tokens = $match[0];

		$is_arg_stack = array();

		for ($i = 0, $size = sizeof($tokens); $i < $size; $i++)

		{

			$token = &$tokens[$i];

			switch ($token)

			{

				case '!==':

				case '===':

				case '<<':

				case '>>':

				case '|':

				case '^':

				case '&':

				case '~':

				case ')':

				case ',':

				case '+':

				case '-':

				case '*':

				case '/':

				case '@':

				break;

				case '==':

				case 'eq':

					$token = '==';

				break;

				case '!=':

				case '<>':

				case 'ne':

				case 'neq':

					$token = '!=';

				break;

				case '<':

				case 'lt':

					$token = '<';

				break;

				case '<=':

				case 'le':

				case 'lte':

					$token = '<=';

				break;

				case '>':

				case 'gt':

					$token = '>';

				break;

				case '>=':

				case 'ge':

				case 'gte':

					$token = '>=';

				break;

				case '&&':

				case 'and':

					$token = '&&';

				break;

				case '||':

				case 'or':

					$token = '||';

				break;

				case '!':

				case 'not':

					$token = '!';

				break;

				case '%':

				case 'mod':

					$token = '%';

				break;

				case '(':

					array_push($is_arg_stack, $i);

				break;

				case 'is':

					$is_arg_start = ($tokens[$i-1] == ')') ? array_pop($is_arg_stack) : $i-1;

					$is_arg	= implode('	', array_slice($tokens,	$is_arg_start, $i -	$is_arg_start));

					$new_tokens	= $this->_parse_is_expr($is_arg, array_slice($tokens, $i+1));

					array_splice($tokens, $is_arg_start, sizeof($tokens), $new_tokens);

					$i = $is_arg_start;

				// no break

				default:

					if (preg_match('#^((?:[a-z0-9\-_]+\.)+)?(\$)?(?=[A-Z])([A-Z0-9\-_]+)#s', $token, $varrefs))

					{

						$token = (!empty($varrefs[1])) ? $this->generate_block_data_ref(substr($varrefs[1], 0, -1), true, $varrefs[2]) . '[\'' . $varrefs[3] . '\']' : (($varrefs[2]) ? '$this->_tpldata[\'DEFINE\'][\'.\'][\'' . $varrefs[3] . '\']' : '$this->_rootref[\'' . $varrefs[3] . '\']');

					}

					else if (preg_match('#^\.((?:[a-z0-9\-_]+\.?)+)$#s', $token, $varrefs))

					{

						// Allow checking if loops are set with .loopname

						// It is also possible to check the loop count by doing  for example

						$blocks = explode('.', $varrefs[1]);

						// If the block is nested, we have a reference that we can grab.

						// If the block is not nested, we just go and grab the block from _tpldata

						if (sizeof($blocks) > 1)

						{

							$block = array_pop($blocks);

							$namespace = implode('.', $blocks);

							$varref = $this->generate_block_data_ref($namespace, true);

							// Add the block reference for the last child.

							$varref .= "['" . $block . "']";

						}

						else

						{

							$varref = '$this->_tpldata';

							// Add the block reference for the last child.

							$varref .= "['" . $blocks[0] . "']";

						}

						$token = "sizeof($varref)";

					}

					else if (!empty($token))

					{

						$token = '(' . $token . ')';

					}

				break;

			}

		}

		// If there are no valid tokens left or only control/compare characters left, we do skip this statement

		if (!sizeof($tokens) || str_replace(array(' ', '=', '!', '<', '>', '&', '|', '%', '(', ')'), '', implode('', $tokens)) == '')

		{

			$tokens = array('false');

		}

		return (($elseif) ? '} else if (' : 'if (') . (implode(' ', $tokens) . ') { ');

	}

	/**

	* Compile DEFINE tags

	* @access private

	*/

	function compile_tag_define($tag_args, $op)

	{

		preg_match('#^((?:[a-z0-9\-_]+\.)+)?\$(?=[A-Z])([A-Z0-9_\-]*)(?: = (\'?)([^\']*)(\'?))?$#', $tag_args, $match);

		if (empty($match[2]) || (!isset($match[4]) && $op))

		{

			return '';

		}

		if (!$op)

		{

			return 'unset(' . (($match[1]) ? $this->generate_block_data_ref(substr($match[1], 0, -1), true, true) . '[\'' . $match[2] . '\']' : '$this->_tpldata[\'DEFINE\'][\'.\'][\'' . $match[2] . '\']') . ');';

		}

		// Are we a string?

		if ($match[3] && $match[5])

		{

			$match[4] = str_replace(array('\\\'', '\\\\', '\''), array('\'', '\\', '\\\''), $match[4]);

			// Compile reference, we allow template variables in defines...

			$match[4] = $this->compile($match[4]);

			// Now replace the php code

			$match[4] = "'" . str_replace(array(''), array("' . ", " . '"), $match[4]) . "'";

		}

		else

		{

			preg_match('#true|false|\.#i', $match[4], $type);

			switch (strtolower($type[0]))

			{

				case 'true':

				case 'false':

					$match[4] = strtoupper($match[4]);

				break;

				case '.':

					$match[4] = doubleval($match[4]);

				break;

				default:

					$match[4] = intval($match[4]);

				break;

			}

		}

		return (($match[1]) ? $this->generate_block_data_ref(substr($match[1], 0, -1), true, true) . '[\'' . $match[2] . '\']' : '$this->_tpldata[\'DEFINE\'][\'.\'][\'' . $match[2] . '\']') . ' = ' . $match[4] . ';';

	}

	/**

	* Compile INCLUDE tag

	* @access private

	*/

	function compile_tag_include($tag_args)

	{

		return "\$this->_tpl_include('$tag_args');";

	}

	/**

	* Compile INCLUDE_PHP tag

	* @access private

	*/

	function compile_tag_include_php($tag_args)

	{

		return "include('" . $tag_args . "');";

	}

	/**

	* parse expression

	* This is from Smarty

	* @access private

	*/

	function _parse_is_expr($is_arg, $tokens)

	{

		$expr_end = 0;

		$negate_expr = false;

		if (($first_token = array_shift($tokens)) == 'not')

		{

			$negate_expr = true;

			$expr_type = array_shift($tokens);

		}

		else

		{

			$expr_type = $first_token;

		}

		switch ($expr_type)

		{

			case 'even':

				if (@$tokens[$expr_end] == 'by')

				{

					$expr_end++;

					$expr_arg = $tokens[$expr_end++];

					$expr = "!(($is_arg / $expr_arg) % $expr_arg)";

				}

				else

				{

					$expr = "!($is_arg & 1)";

				}

			break;

			case 'odd':

				if (@$tokens[$expr_end] == 'by')

				{

					$expr_end++;

					$expr_arg = $tokens[$expr_end++];

					$expr = "(($is_arg / $expr_arg) % $expr_arg)";

				}

				else

				{

					$expr = "($is_arg & 1)";

				}

			break;

			case 'div':

				if (@$tokens[$expr_end] == 'by')

				{

					$expr_end++;

					$expr_arg = $tokens[$expr_end++];

					$expr = "!($is_arg % $expr_arg)";

				}

			break;

		}

		if ($negate_expr)

		{

			$expr = "!($expr)";

		}

		array_splice($tokens, 0, $expr_end, $expr);

		return $tokens;

	}

	/**

	* Generates a reference to the given variable inside the given (possibly nested)

	* block namespace. This is a string of the form:

	* ' . $this->_tpldata['parent'][$_parent_i]['$child1'][$_child1_i]['$child2'][$_child2_i]...['varname'] . '

	* It's ready to be inserted into an "echo" line in one of the templates.

	* NOTE: expects a trailing "." on the namespace.

	* @access private

	*/

	function generate_block_varref($namespace, $varname, $echo = true, $defop = false)

	{

		// Strip the trailing period.

		$namespace = substr($namespace, 0, -1);

		// Get a reference to the data block for this namespace.

		$varref = $this->generate_block_data_ref($namespace, true, $defop);

		// Prepend the necessary code to stick this in an echo line.

		// Append the variable reference.

		$varref .= "['$varname']";

		$varref = ($echo) ? "" : ((isset($varref)) ? $varref : '');

		return $varref;

	}

	/**

	* Generates a reference to the array of data values for the given

	* (possibly nested) block namespace. This is a string of the form:

	* $this->_tpldata['parent'][$_parent_i]['$child1'][$_child1_i]['$child2'][$_child2_i]...['$childN']

	*

	* If $include_last_iterator is true, then [$_childN_i] will be appended to the form shown above.

	* NOTE: does not expect a trailing "." on the blockname.

	* @access private

	*/

	function generate_block_data_ref($blockname, $include_last_iterator, $defop = false)

	{

		// Get an array of the blocks involved.

		$blocks = explode('.', $blockname);

		$blockcount = sizeof($blocks) - 1;

		// DEFINE is not an element of any referenced variable, we must use _tpldata to access it

		if ($defop)

		{

			$varref = '$this->_tpldata[\'DEFINE\']';

			// Build up the string with everything but the last child.

			for ($i = 0; $i < $blockcount; $i++)