<?

/**
 * This class emulate the behavior of the 
 * ConfigurationSettings.AppSettings class of the .NET framework.
 * With this class you can write and read a Web.config file or a 
 * App.config file handled in the most common applications written 
 * in C#, VisualBasic.NET, J# or C++.NET
 *
 */
class AppSettings
{
	var $CurrentDir;
	var $PathSeparator;
	var $XmlDocument;
	var $ConfigFile;
	var $ConfigFileName = "Web.config";

	/**
	 * Constructor. Sets the working directory, the path separator, 
	 * and the location of the config file. Then, it calls a method
	 * that loads the config file into a Dom Object
	 * 
	 *
	 * @return AppSettings
	 */
	function AppSettings()
	{
		$this->CurrentDir = getcwd();
		$this->PathSeparator = DIRECTORY_SEPARATOR;
		$this->ConfigFile = $this->CurrentDir . $this->PathSeparator . $this->ConfigFileName;
		$this->CreateOrLoadConfigFile();
	}
	/**
	 * Get the value of the element 'key'
	 *
	 * @param string $key
	 * @return string
	 */
	function Get($key)
	{
		$xpath = $this->XmlDocument->xpath_new_context();
		$obj = $xpath->xpath_eval("//configuration/appSettings/add[@key='$key']"); 
		if($obj->nodeset[0] != null)
			return $obj->nodeset[0]->get_attribute("value");
		else return;
	}
	/**
	 * Set the given name and value.
	 * If the file already has the element, replaces the value with the
	 * given value
	 *
	 * @param string $key
	 * @param string $value
	 */
	function Put($key, $value)
	{
		if ( $this->Get($key) == "" )
		{
			$xpath = $this->XmlDocument->xpath_new_context();
			$obj = $xpath->xpath_eval("//configuration/appSettings"); 
	
			$add = $this->XmlDocument->create_element("add");
			$add->set_attribute("key", $key);
			$add->set_attribute("value", $value);
			$obj->nodeset[0]->append_child($add);
		}
		else 
		{
			$xpath = $this->XmlDocument->xpath_new_context();
			$old = $xpath->xpath_eval("//configuration/appSettings/add[@key='$key']");
			$old->nodeset[0]->set_attribute("value", $value);
		}
		$this->XmlDocument->dump_file($this->ConfigFile, false, true);
	}
	/**
	 * This method load the config file.
	 * If doesn't exists, try to create it.
	 * The working directory must have write permissions.
	 *
	 */
	function CreateOrLoadConfigFile()
	{
		if(!file_exists($this->ConfigFile))
		{
			$this->XmlDocument = domxml_new_doc("1.0");
			$root = $this->XmlDocument->add_root("configuration");
			$appSettings = $this->XmlDocument->create_element("appSettings");
			$root->append_child($appSettings);
			$this->XmlDocument->dump_file($this->ConfigFile, false, true);
		}
		else 
		{
			$this->XmlDocument = domxml_open_file($this->ConfigFile);
		}
	}
}
?>