<?php
/**
 * Main template class
 * @example:
 * <code>
 * <?php
 * $tpl = new Template();
 * $tpl->somevar = "some value";
 * $tpl->applyTemplate(templatefile);
 * </code>
 * 
 * @package frea-framework
 * @version 1.0RC
 * @copyright 2009 frea-framework
 * @author Dawid Kraczkowski hide@address.com
 * @license  http://www.gnu.org/licenses/lgpl.html GNU Lesser General Public License
 *
 */
class Template
{
	/**
	 * Directory path to cache folder
	 *
	 * @var string
	 */
	static private $cacheDirectory;
	/**
	 * Directory path to template folder
	 *
	 * @var unknown_type
	 */
	static private $templateDirectory;
	/**
	 * Context holder
	 *
	 * @var Template_VariableContainer
	 */
	private $variableContainer;
	
	/**
	 * Constructor
	 *
	 */
	public function __construct()
	{
		if (function_exists('sys_get_temp_dir') and empty(self::$cacheDirectory)) #check for system temp directory
		{
            self::setCacheDirectory(sys_get_temp_dir());
        } 
        elseif (substr(PHP_OS, 0, 3) == 'WIN') #windows
        {
            if (file_exists('c:\\WINNT\\Temp\\')) 
            {
                self::setCacheDirectory('c:\\WINNT\\Temp');
            } 
            else 
            {
                self::setCacheDirectory('c:\\WINDOWS\\Temp\\');
            }
        }
        //create context
        $this->variableContainer = new Template_VariableContainer();
	}
	/**
	 * Gets assigned variable from context
	 *
	 * @param string $name
	 */
	public function __get($name)
	{
		$this->variableContainer->$name;
	}
	/**
	 * assign variable to a context
	 *
	 * @param string $name
	 * @param mixed $value
	 */
	public function __set($name,$value)
	{
		$this->variableContainer->$name = $value;
	}
	/**
	 * parse given template
	 *
	 * @param string $filename
	 * @throws Template_Exception
	 */
	public function applyTemplate($filename)
	{
		//check for cachedir
		if(empty(self::$cacheDirectory) or !is_dir(self::$cacheDirectory))
			throw new Template_Exception("You must define proper cache directory!");
		
		//check for templatefile
		if(!is_readable($filename))
		{
			if(!is_readable(self::$templateDirectory.$filename))
				throw new Template_Exception("Cannot read from file {$filename}");
			else 
				$filename = self::$templateDirectory.$filename;
		}
		
		//handle cache file
		$cachefile = self::getCacheDirecotry().str_replace(DIRECTORY_SEPARATOR,"_",$filename);
		
		if(is_readable($cachefile) && filemtime($cachefile)>filemtime($filename))
		{
			$eval = eval("?>".file_get_contents($cachefile));
		}
		else 
		{
			$cp = new Template_Dom_Parser($filename);
			$cb = new Template_CodeBuilder($cp->parse(),$cachefile);
			$eval = $cb->build();
			
		}
		echo eval("?>".$eval);
			
	}
	/**
	 * import to template external template
	 * file
	 *
	 * @param string $path
	 * @return string
	 */
	static public function  import($path)
	{
		$cachefile = self::getCacheDirecotry().str_replace(DIRECTORY_SEPARATOR,"_",$path);
			
		if(!is_readable($cachefile) or filemtime($cachefile)<=filemtime($path))
		{
			$cp = new Template_Dom_Parser($path);
			$cb = new Template_CodeBuilder($cp->parse(),$cachefile);
			$cb->build();
		}
		return eval("?>".file_get_contents($cachefile));
	}
	/**
	 * sets directory path for cached files
	 *
	 * @param string $directory
	 */
	static public function setCacheDirectory($directory)
	{
		$p = strlen($directory)-1;
		if(substr($directory,$p) != DIRECTORY_SEPARATOR)
			$directory .= DIRECTORY_SEPARATOR;
		self::$cacheDirectory = $directory;
	}
	/**
	 * gets cache directory path
	 *
	 * @return string
	 */
	static public function getCacheDirecotry()
	{
		return self::$cacheDirectory;
	}
	/**
	 * sets template direcorty
	 *
	 * @param string $directory
	 */
	static public function setTemplateDirectory($directory)
	{
		$p = strlen($directory)-1;
		if(substr($directory,$p) != DIRECTORY_SEPARATOR)
			$directory .= DIRECTORY_SEPARATOR;
		self::$templateDirectory = $directory;
	}
	/**
	 * gets template direcotry
	 *
	 * @return string
	 */
	static public function getTemplateDirectory()
	{
		return self::$templateDirectory;
	}
	
}