<?php

	####
	## class Template
	##
	## Author: Bill Hunt (bill@krues8dr.com)
	##
	## Purpose : Replaces tags from a template file with content 
	## passed to the function.
	##
	## Change Log:
	## 10.30.03 - Created file.
	## 06.21.04 - Changed argument list.
	## 10.06.04 - Changed file to die on template file Does Not Exist.
	## 01.11.06 - Created class, adapted function.
	##          - Replaced die() with trigger_error()
	## 06.12.06 - Added php execution and replacement.
	## 06.14.06 - Added xml exclusion from php execution
	####
	class Template {

		var $replace_pattern = '/\<!--([A-Za-z0-9_-]+)--\>/';
		var $global_replacements = array();
		
		var $xml_replacements = array();
		
		function Template($args = null) {
			$this->global_replacements['current_year'] = date('Y');
		}
		
		// function show()
		// Takes either a 'template_file' argument or 'template',
		// containing the actual template data itself.
		function show($args) {
			if($args['template_file']) {
				$filename = $args['template_file'];		
				if(file_exists($filename)) {
					$file_data = file_get_contents($filename);
				} 
				else { // File DNE.
					//return false;
					trigger_error('Template File does not exist: "'.$filename.'"', E_USER_ERROR);
				}
			}
			elseif($args['template']) {
				$file_data = $args['template'];
			}
			else {
				trigger_error('No template passed to Template class', E_USER_ERROR);
			}
			
			$args['replacements'] = array_merge($this->global_replacements, $args['replacements']);
			
			if(is_array($args['replacements']) && count($args['replacements'])) {
				foreach($args['replacements'] as $key=>$value) {
					$file_data = str_replace('<!--'.strtoupper($key).'-->', $value, $file_data); 
				}
			}
			
			// Before we can eval() html, we must remove any xml within it.
			$expression = '/<\\?xml(.*?)\\?>/s';
			// The trailing "s" there lets the "." metachar accept newlines.
			$file_data = preg_replace_callback($expression, array(&$this, 'preg_catch_xml'), $file_data);
			
			// You can eval() html, but you have to fake out the parser by putting 
			// a closing php tag before it.  Adding a trailing opening tag will cause an error.
			ob_start();
			eval('?>'.$file_data);
			$file_data = ob_get_contents();
			ob_end_clean();
			
			if(is_array($this->xml_replacements) && count($this->xml_replacements)) {
				foreach($this->xml_replacements as $key=>$value) {
					$file_data = str_replace($key, $value, $file_data);
				}
			}
			
			return $file_data;
		}
		
		function preg_catch_xml($matches) {
			$index_id = count($this->xml_replacements);
			
			$index_name = '<!--REPLACE_XML_'.$index_id.'-->';
			
			$this->xml_replacements[$index_name] = $matches[0];
			
			return $index_name;
		}

	}

?>