/includes/template.php

<?php
/**
*
* @package phpBB3
* @version $Id$
* @copyright (c) 2005 phpBB Group, sections (c) 2001 ispi of Lincoln Inc
* @license http://opensource.org/licenses/gpl-license.php GNU Public License
*
*/

/**
* Base Template class.
* @package phpBB3
*/
class template
{
	/** variable that holds all the data we'll be substituting into
	* the compiled templates. Takes form:
	* --> $this->_tpldata[block][iteration#][child][iteration#][child2][iteration#][variablename] == value
	* if it's a root-level variable, it'll be like this:
	* --> $this->_tpldata[.][0][varname] == value
	*/
	var $_tpldata = array('.' => array(0 => array()));
	var $_rootref;

	// Root dir and hash of filenames for each template handle.
	var $root = '';
	var $cachepath = '';
	var $files = array();
	var $filename = array();
	var $files_inherit = array();
	var $files_template = array();
	var $inherit_root = '';
	var $orig_tpl_storedb;
	var $orig_tpl_inherits_id;

	// this will hash handle names to the compiled/uncompiled code for that handle.
	var $compiled_code = array();

	/**
	* Set template location
	* @access public
	*/
	function set_template()
	{
		global $phpbb_root_path, $user;

		if (file_exists($phpbb_root_path . 'styles/' . $user->theme['template_path'] . '/template'))
		{
			$this->root = $phpbb_root_path . 'styles/' . $user->theme['template_path'] . '/template';
			$this->cachepath = $phpbb_root_path . 'cache/tpl_' . str_replace('_', '-', $user->theme['template_path']) . '_';

			if ($this->orig_tpl_storedb === null)
			{
				$this->orig_tpl_storedb = $user->theme['template_storedb'];
			}

			if ($this->orig_tpl_inherits_id === null)
			{
				$this->orig_tpl_inherits_id = $user->theme['template_inherits_id'];
			}

			$user->theme['template_storedb'] = $this->orig_tpl_storedb;
			$user->theme['template_inherits_id'] = $this->orig_tpl_inherits_id;

			if ($user->theme['template_inherits_id'])
			{
				$this->inherit_root = $phpbb_root_path . 'styles/' . $user->theme['template_inherit_path'] . '/template';
			}
		}
		else
		{
			trigger_error('Template path could not be found: styles/' . $user->theme['template_path'] . '/template', E_USER_ERROR);
		}

		$this->_rootref = &$this->_tpldata['.'][0];

		return true;
	}

	/**
	* Set custom template location (able to use directory outside of phpBB)
	* @access public
	*/
	function set_custom_template($template_path, $template_name, $fallback_template_path = false)
	{
		global $phpbb_root_path, $user;

		// Make sure $template_path has no ending slash
		if (substr($template_path, -1) == '/')
		{
			$template_path = substr($template_path, 0, -1);
		}

		$this->root = $template_path;
		$this->cachepath = $phpbb_root_path . 'cache/ctpl_' . str_replace('_', '-', $template_name) . '_';

		if ($fallback_template_path !== false)
		{
			if (substr($fallback_template_path, -1) == '/')
			{
				$fallback_template_path = substr($fallback_template_path, 0, -1);
			}

			$this->inherit_root = $fallback_template_path;
			$this->orig_tpl_inherits_id = true;
		}
		else
		{
			$this->orig_tpl_inherits_id = false;
		}

		// the database does not store the path or name of a custom template
		// so there is no way we can properly store custom templates there
		$this->orig_tpl_storedb = false;

		$this->_rootref = &$this->_tpldata['.'][0];

		return true;
	}

	/**
	* Sets the template filenames for handles. $filename_array
	* should be a hash of handle => filename pairs.
	* @access public
	*/
	function set_filenames($filename_array)
	{
		if (!is_array($filename_array))
		{
			return false;
		}
		foreach ($filename_array as $handle => $filename)
		{
			if (empty($filename))
			{
				trigger_error("template->set_filenames: Empty filename specified for $handle", E_USER_ERROR);
			}

			$this->filename[$handle] = $filename;
			$this->files[$handle] = $this->root . '/' . $filename;

			if ($this->inherit_root)
			{
				$this->files_inherit[$handle] = $this->inherit_root . '/' . $filename;
			}
		}

		return true;
	}

	/**
	* Destroy template data set
	* @access public
	*/
	function destroy()
	{
		$this->_tpldata = array('.' => array(0 => array()));
		$this->_rootref = &$this->_tpldata['.'][0];
	}

	/**
	* Reset/empty complete block
	* @access public
	*/
	function destroy_block_vars($blockname)
	{
		if (strpos($blockname, '.') !== false)
		{
			// Nested block.
			$blocks = explode('.', $blockname);
			$blockcount = sizeof($blocks) - 1;

			$str = &$this->_tpldata;
			for ($i = 0; $i < $blockcount; $i++)
			{
				$str = &$str[$blocks[$i]];
				$str = &$str[sizeof($str) - 1];
			}

			unset($str[$blocks[$blockcount]]);
		}
		else
		{
			// Top-level block.
			unset($this->_tpldata[$blockname]);
		}

		return true;
	}

	/**
	* Display handle
	* @access public
	*/
	function display($handle, $include_once = true)
	{
		global $user, $phpbb_hook;

		if (!empty($phpbb_hook) && $phpbb_hook->call_hook(array(__CLASS__, __FUNCTION__), $handle, $include_once, $this))
		{
			if ($phpbb_hook->hook_return(array(__CLASS__, __FUNCTION__)))
			{
				return $phpbb_hook->hook_return_result(array(__CLASS__, __FUNCTION__));
			}
		}

		if (defined('IN_ERROR_HANDLER'))
		{
			if ((E_NOTICE & error_reporting()) == E_NOTICE)
			{
				error_reporting(error_reporting() ^ E_NOTICE);
			}
		}

		if ($filename = $this->_tpl_load($handle))
		{
			($include_once) ? include_once($filename) : include($filename);
		}
		else
		{
			eval(' ?>' . $this->compiled_code[$handle] . '<?php ');
		}

		return true;
	}

	/**
	* Display the handle and assign the output to a template variable or return the compiled result.
	* @access public
	*/
	function assign_display($handle, $template_var = '', $return_content = true, $include_once = false)
	{
		ob_start();
		$this->display($handle, $include_once);
		$contents = ob_get_clean();

		if ($return_content)
		{
			return $contents;
		}

		$this->assign_var($template_var, $contents);

		return true;
	}

	/**
	* Load a compiled template if possible, if not, recompile it
	* @access private
	*/
	function _tpl_load(&$handle)
	{
		global $user, $phpEx, $config;

		if (!isset($this->filename[$handle]))
		{
			trigger_error("template->_tpl_load(): No file specified for handle $handle", E_USER_ERROR);
		}

		// reload these settings to have the values they had when this object was initialised
		// using set_template or set_custom_template, they might otherwise have been overwritten
		// by other template class instances in between.
		//$user->theme['template_storedb'] = $this->orig_tpl_storedb;
		//$user->theme['template_inherits_id'] = $this->orig_tpl_inherits_id;

		$filename = $this->cachepath . str_replace('/', '.', $this->filename[$handle]) . '.' . $phpEx;
		$this->files_template[$handle] = (isset($user->theme['template_id'])) ? $user->theme['template_id'] : 0;

		$recompile = false;
		if (!file_exists($filename) || @filesize($filename) === 0 || defined('DEBUG_EXTRA'))
		{
			$recompile = true;
		}
		else if ($config['load_tplcompile'])
		{
			// No way around it: we need to check inheritance here
			if ($user->theme['template_inherits_id'] && !file_exists($this->files[$handle]))
			{
				$this->files[$handle] = $this->files_inherit[$handle];
				$this->files_template[$handle] = $user->theme['template_inherits_id'];
			}
			$recompile = (@filemtime($filename) < filemtime($this->files[$handle])) ? true : false;
		}

		// Recompile page if the original template is newer, otherwise load the compiled version
		if (!$recompile)
		{
			return $filename;
		}

		global $db, $phpbb_root_path;

		if (!class_exists('template_compile'))
		{
			include($phpbb_root_path . 'includes/functions_template.' . $phpEx);
		}

		// Inheritance - we point to another template file for this one. Equality is also used for store_db
		if (isset($user->theme['template_inherits_id']) && $user->theme['template_inherits_id'] && !file_exists($this->files[$handle]))
		{
			$this->files[$handle] = $this->files_inherit[$handle];
			$this->files_template[$handle] = $user->theme['template_inherits_id'];
		}

		$compile = new template_compile($this);

		// If we don't have a file assigned to this handle, die.
		if (!isset($this->files[$handle]))
		{
			trigger_error("template->_tpl_load(): No file specified for handle $handle", E_USER_ERROR);
		}

		// Just compile if no user object is present (happens within the installer)
		if (!$user)
		{
			$compile->_tpl_load_file($handle);
			return false;
		}

		if (isset($user->theme['template_storedb']) && $user->theme['template_storedb'])
		{
			$rows = array();
			$ids = array();
			// Inheritance
			if (isset($user->theme['template_inherits_id']) && $user->theme['template_inherits_id'])
			{
				$ids[] = $user->theme['template_inherits_id'];
			}
			$ids[] = $user->theme['template_id'];

			foreach ($ids as $id)
			{
				$sql = 'SELECT *
				FROM ' . STYLES_TEMPLATE_DATA_TABLE . '
				WHERE template_id = ' . $id . "
					AND (template_filename = '" . $db->sql_escape($this->filename[$handle]) . "'
						OR template_included " . $db->sql_like_expression($db->any_char . $this->filename[$handle] . ':' . $db->any_char) . ')';

				$result = $db->sql_query($sql);
				while ($row = $db->sql_fetchrow($result))
				{
					$rows[$row['template_filename']] = $row;
				}
				$db->sql_freeresult($result);
			}

			if (sizeof($rows))
			{
				foreach ($rows as $row)
				{
					$file = $this->root . '/' . $row['template_filename'];
					$force_reload = false;
					if ($row['template_id'] != $user->theme['template_id'])
					{
						// make sure that we are not overlooking a file not in the db yet
						if (isset($user->theme['template_inherits_id']) && $user->theme['template_inherits_id'] && !file_exists($file))
						{
							$file = $this->inherit_root . '/' . $row['template_filename'];
							$this->files[$row['template_filename']] = $file;
							$this->files_inherit[$row['template_filename']] = $file;
							$this->files_template[$row['template_filename']] = $user->theme['template_inherits_id'];
						}
						else if (isset($user->theme['template_inherits_id']) && $user->theme['template_inherits_id'])
						{
							// Ok, we have a situation. There is a file in the subtemplate, but nothing in the DB. We have to fix that.
							$force_reload = true;
							$this->files_template[$row['template_filename']] = $user->theme['template_inherits_id'];
						}
					}
					else
					{
						$this->files_template[$row['template_filename']] = $user->theme['template_id'];
					}

					if ($force_reload || $row['template_mtime'] < filemtime($file))
					{
						if ($row['template_filename'] == $this->filename[$handle])
						{
							$compile->_tpl_load_file($handle, true);
						}
						else
						{
							$this->files[$row['template_filename']] = $file;
							$this->filename[$row['template_filename']] = $row['template_filename'];
							$compile->_tpl_load_file($row['template_filename'], true);
							unset($this->compiled_code[$row['template_filename']]);
							unset($this->files[$row['template_filename']]);
							unset($this->filename[$row['template_filename']]);
						}
					}

					if ($row['template_filename'] == $this->filename[$handle])
					{
						$this->compiled_code[$handle] = $compile->compile(trim($row['template_data']));
						$compile->compile_write($handle, $this->compiled_code[$handle]);
					}
					else
					{
						// Only bother compiling if it doesn't already exist
						if (!file_exists($this->cachepath . str_replace('/', '.', $row['template_filename']) . '.' . $phpEx))
						{
							$this->filename[$row['template_filename']] = $row['template_filename'];
							$compile->compile_write($row['template_filename'], $compile->compile(trim($row['template_data'])));
							unset($this->filename[$row['template_filename']]);
						}
					}
				}
			}
			else
			{
				$file = $this->root . '/' . $row['template_filename'];

				if (isset($user->theme['template_inherits_id']) && $user->theme['template_inherits_id'] && !file_exists($file))
				{
					$file = $this->inherit_root . '/' . $row['template_filename'];
					$this->files[$row['template_filename']] = $file;
					$this->files_inherit[$row['template_filename']] = $file;
					$this->files_template[$row['template_filename']] = $user->theme['template_inherits_id'];
				}
				// Try to load from filesystem and instruct to insert into the styles table...
				$compile->_tpl_load_file($handle, true);
				return false;
			}

			return false;
		}

		$compile->_tpl_load_file($handle);
		return false;
	}

	/**
	* Assign key variable pairs from an array
	* @access public
	*/
	function assign_vars($vararray)
	{
		foreach ($vararray as $key => $val)
		{
			$this->_rootref[$key] = $val;
		}

		return true;
	}

	/**
	* Assign a single variable to a single key
	* @access public
	*/
	function assign_var($varname, $varval)
	{
		$this->_rootref[$varname] = $varval;

		return true;
	}

	/**
	* Assign key variable pairs from an array to a specified block
	* @access public
	*/
	function assign_block_vars($blockname, $vararray)
	{
		if (strpos($blockname, '.') !== false)
		{
			// Nested block.
			$blocks = explode('.', $blockname);
			$blockcount = sizeof($blocks) - 1;

			$str = &$this->_tpldata;
			for ($i = 0; $i < $blockcount; $i++)
			{
				$str = &$str[$blocks[$i]];
				$str = &$str[sizeof($str) - 1];
			}

			$s_row_count = isset($str[$blocks[$blockcount]]) ? sizeof($str[$blocks[$blockcount]]) : 0;
			$vararray['S_ROW_COUNT'] = $s_row_count;

			// Assign S_FIRST_ROW
			if (!$s_row_count)
			{
				$vararray['S_FIRST_ROW'] = true;
			}

			// Now the tricky part, we always assign S_LAST_ROW and remove the entry before
			// This is much more clever than going through the complete template data on display (phew)
			$vararray['S_LAST_ROW'] = true;
			if ($s_row_count > 0)
			{
				unset($str[$blocks[$blockcount]][($s_row_count - 1)]['S_LAST_ROW']);
			}

			// Now we add the block that we're actually assigning to.
			// We're adding a new iteration to this block with the given
			// variable assignments.
			$str[$blocks[$blockcount]][] = $vararray;
		}
		else
		{
			// Top-level block.
			$s_row_count = (isset($this->_tpldata[$blockname])) ? sizeof($this->_tpldata[$blockname]) : 0;
			$vararray['S_ROW_COUNT'] = $s_row_count;

			// Assign S_FIRST_ROW
			if (!$s_row_count)
			{
				$vararray['S_FIRST_ROW'] = true;
			}

			// We always assign S_LAST_ROW and remove the entry before
			$vararray['S_LAST_ROW'] = true;
			if ($s_row_count > 0)
			{
				unset($this->_tpldata[$blockname][($s_row_count - 1)]['S_LAST_ROW']);
			}

			// Add a new iteration to this block with the variable assignments we were given.
			$this->_tpldata[$blockname][] = $vararray;
		}

		return true;
	}

	/**
	* Change already assigned key variable pair (one-dimensional - single loop entry)
	*
	* An example of how to use this function:
	* {@example alter_block_array.php}
	*
	* @param	string	$blockname	the blockname, for example 'loop'
	* @param	array	$vararray	the var array to insert/add or merge
	* @param	mixed	$key		Key to search for
	*
	* array: KEY => VALUE [the key/value pair to search for within the loop to determine the correct position]
	*
	* int: Position [the position to change or insert at directly given]
	*
	* If key is false the position is set to 0
	* If key is true the position is set to the last entry
	*
	* @param	string	$mode		Mode to execute (valid modes are 'insert' and 'change')
	*
	*	If insert, the vararray is inserted at the given position (position counting from zero).
	*	If change, the current block gets merged with the vararray (resulting in new key/value pairs be added and existing keys be replaced by the new value).
	*
	* Since counting begins by zero, inserting at the last position will result in this array: array(vararray, last positioned array)
	* and inserting at position 1 will result in this array: array(first positioned array, vararray, following vars)
	*
	* @return bool false on error, true on success
	* @access public
	*/
	function alter_block_array($blockname, $vararray, $key = false, $mode = 'insert')
	{
		if (strpos($blockname, '.') !== false)
		{
			// Nested blocks are not supported
			return false;
		}

		// Change key to zero (change first position) if false and to last position if true
		if ($key === false || $key === true)
		{
			$key = ($key === false) ? 0 : sizeof($this->_tpldata[$blockname]);
		}

		// Get correct position if array given
		if (is_array($key))
		{
			// Search array to get correct position
			list($search_key, $search_value) = @each($key);

			$key = NULL;
			foreach ($this->_tpldata[$blockname] as $i => $val_ary)
			{
				if ($val_ary[$search_key] === $search_value)
				{
					$key = $i;
					break;
				}
			}

			// key/value pair not found
			if ($key === NULL)
			{
				return false;
			}
		}

		// Insert Block
		if ($mode == 'insert')
		{
			// Make sure we are not exceeding the last iteration
			if ($key >= sizeof($this->_tpldata[$blockname]))
			{
				$key = sizeof($this->_tpldata[$blockname]);
				unset($this->_tpldata[$blockname][($key - 1)]['S_LAST_ROW']);
				$vararray['S_LAST_ROW'] = true;
			}
			else if ($key === 0)
			{
				unset($this->_tpldata[$blockname][0]['S_FIRST_ROW']);
				$vararray['S_FIRST_ROW'] = true;
			}

			// Re-position template blocks
			for ($i = sizeof($this->_tpldata[$blockname]); $i > $key; $i--)
			{
				$this->_tpldata[$blockname][$i] = $this->_tpldata[$blockname][$i-1];
				$this->_tpldata[$blockname][$i]['S_ROW_COUNT'] = $i;
			}

			// Insert vararray at given position
			$vararray['S_ROW_COUNT'] = $key;
			$this->_tpldata[$blockname][$key] = $vararray;

			return true;
		}

		// Which block to change?
		if ($mode == 'change')
		{
			if ($key == sizeof($this->_tpldata[$blockname]))
			{
				$key--;
			}

			$this->_tpldata[$blockname][$key] = array_merge($this->_tpldata[$blockname][$key], $vararray);
			return true;
		}

		return false;
	}

	/**
	* Include a separate template
	* @access private
	*/
	function _tpl_include($filename, $include = true)
	{
		$handle = $filename;
		$this->filename[$handle] = $filename;
		$this->files[$handle] = $this->root . '/' . $filename;
		if ($this->inherit_root)
		{
			$this->files_inherit[$handle] = $this->inherit_root . '/' . $filename;
		}

		$filename = $this->_tpl_load($handle);

		if ($include)
		{
			global $user;

			if ($filename)
			{
				include($filename);
				return;
			}
			eval(' ?>' . $this->compiled_code[$handle] . '<?php ');
		}
	}

	/**
	* Include a php-file
	* @access private
	*/
	function _php_include($filename)
	{
		global $phpbb_root_path;

		$file = $phpbb_root_path . $filename;

		if (!file_exists($file))
		{
			// trigger_error cannot be used here, as the output already started
			echo 'template->_php_include(): File ' . htmlspecialchars($file) . ' does not exist or is empty';
			return;
		}
		include($file);
	}
}


/**
* 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('#<!-- PHP -->(.*?)<!-- ENDPHP -->#s', $code, $matches);
		$php_blocks = $matches[1];
		$code = preg_replace('#<!-- PHP -->.*?<!-- ENDPHP -->#s', '<!-- PHP -->', $code);

		preg_match_all('#<!-- INCLUDE (\{\$?[A-Z0-9\-_]+\}|[a-zA-Z0-9\_\-\+\./]+) -->#', $code, $matches);
		$include_blocks = $matches[1];
		$code = preg_replace('#<!-- INCLUDE (?:\{\$?[A-Z0-9\-_]+\}|[a-zA-Z0-9\_\-\+\./]+) -->#', '<!-- INCLUDE -->', $code);

		preg_match_all('#<!-- INCLUDEPHP ([a-zA-Z0-9\_\-\+\./]+) -->#', $code, $matches);
		$includephp_blocks = $matches[1];
		$code = preg_replace('#<!-- INCLUDEPHP [a-zA-Z0-9\_\-\+\./]+ -->#', '<!-- INCLUDEPHP -->', $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[] = '<?php ' . $this->compile_tag_block($block_val[2]) . ' ?>';
				break;

				case 'BEGINELSE':
					$this->block_else_level[sizeof($this->block_else_level) - 1] = true;
					$compile_blocks[] = '<?php }} else { ?>';
				break;

				case 'END':
					array_pop($this->block_names);
					$compile_blocks[] = '<?php ' . ((array_pop($this->block_else_level)) ? '}' : '}}') . ' ?>';
				break;

				case 'IF':
					$compile_blocks[] = '<?php ' . $this->compile_tag_if($block_val[2], false) . ' ?>';
				break;

				case 'ELSE':
					$compile_blocks[] = '<?php } else { ?>';
				break;

				case 'ELSEIF':
					$compile_blocks[] = '<?php ' . $this->compile_tag_if($block_val[2], true) . ' ?>';
				break;

				case 'ENDIF':
					$compile_blocks[] = '<?php } ?>';
				break;

				case 'DEFINE':
					$compile_blocks[] = '<?php ' . $this->compile_tag_define($block_val[2], true) . ' ?>';
				break;

				case 'UNDEFINE':
					$compile_blocks[] = '<?php ' . $this->compile_tag_define($block_val[2], false) . ' ?>';
				break;

				case 'INCLUDE':
					$temp = array_shift($include_blocks);

					// Dynamic includes
					// Cheap match rather than a full blown regexp, we already know
					// the format of the input so just use string manipulation.
					if ($temp[0] == '{')
					{
						$file = false;

						if ($temp[1] == '$')
						{
							$var = substr($temp, 2, -1);
							//$file = $this->template->_tpldata['DEFINE']['.'][$var];
							$temp = "\$this->_tpldata['DEFINE']['.']['$var']";
						}
						else
						{
							$var = substr($temp, 1, -1);
							//$file = $this->template->_rootref[$var];
							$temp = "\$this->_rootref['$var']";
						}
					}
					else
					{
						$file = $temp;
					}

					$compile_blocks[] = '<?php ' . $this->compile_tag_include($temp) . ' ?>';

					// No point in checking variable includes
					if ($file)
					{
						$this->template->_tpl_include($file, false);
					}
				break;

				case 'INCLUDEPHP':
					$compile_blocks[] = ($config['tpl_allow_php']) ? '<?php ' . $this->compile_tag_include_php(array_shift($includephp_blocks)) . ' ?>' : '';
				break;

				case 'PHP':
					$compile_blocks[] = ($config['tpl_allow_php']) ? '<?php ' . array_shift($php_blocks) . ' ?>' : '';
				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] : '');
		}

		// Remove unused opening/closing tags
		$template_php = str_replace(' ?><?php ', ' ', $template_php);

		// Now add a newline after each php closing tag which already has a newline
		// PHP itself strips a newline if a closing tag is used (this is documented behaviour) and it is mostly not intended by style authors to remove newlines
		$template_php = preg_replace('#\?\>([\r\n])#', '?>\1\1', $template_php);

		// 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
		if ($no_echo)
		{
			return "\$$echo_var .= '" . $template_php . "'";
		}

		return $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\-_]+)\}#', "<?php echo ((isset(\$this->_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\-_]+)\}#', "<?php echo ((isset(\$this->_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\-_]+)\}#', "<?php echo (isset(\$this->_rootref['\\1'])) ? \$this->_rootref['\\1'] : ''; ?>", $text_blocks);
		$text_blocks = preg_replace('#\{\$([A-Z0-9\-_]+)\}#', "<?php echo (isset(\$this->_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 of ! 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
		* <code>
		*	if (!$offset)
		*	{
		*		$tag_template_php .= 'foreach (' . $varref . ' as $_' . $tag_args . '_i => $_' . $tag_args . '_val){';
		*	}
		* </code>
		*/

		$tag_template_php .= 'for ($_' . $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 <!-- IF .loopname > 1 --> 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('<?php echo ', '; ?>'), 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($tag_args)
	{
		// Process dynamic includes
		if ($tag_args[0] == '$')
		{
			return "if (isset($tag_args)) { \$this->_tpl_include($tag_args); }";
		}

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

	/**
	* Compile INCLUDE_PHP tag
	* @access private
	*/
	function compile_tag_include_php($tag_args)
	{
		return "\$this->_php_include('$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) ? "<?php echo $varref; ?>" : ((isset($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++)
			{
				$varref .= "['" . $blocks[$i] . "'][\$_" . $blocks[$i] . '_i]';
			}
			// Add the block reference for the last child.
			$varref .= "['" . $blocks[$blockcount] . "']";
			// Add the iterator for the last child if requried.
			if ($include_last_iterator)
			{
				$varref .= '[$_' . $blocks[$blockcount] . '_i]';
			}
			return $varref;
		}
		else if ($include_last_iterator)
		{
			return '$_'. $blocks[$blockcount] . '_val';
		}
		else
		{
			return '$_'. $blocks[$blockcount - 1] . '_val[\''. $blocks[$blockcount]. '\']';
		}
	}

	/**
	* Write compiled file to cache directory
	* @access private
	*/
	function compile_write($handle, $data)
	{
		global $phpEx;

		$filename = $this->template->cachepath . str_replace('/', '.', $this->template->filename[$handle]) . '.' . $phpEx;

		$data = "<?php" . ((strpos($data, '<?php') === 0) ? substr($data, 5) : ' ?>' . $data);

		if ($fp = @fopen($filename, 'wb'))
		{
			@flock($fp, LOCK_EX);
			@fwrite ($fp, $data);
			@flock($fp, LOCK_UN);
			@fclose($fp);

			chmod($filename, 0777);
			//phpbb_chmod($filename, CHMOD_READ | CHMOD_WRITE);
		}

		return;
	}
}