<?php

class ElementSet extends Element {
	
	private static $schema;
	
	public static function getDefinition () {
		
		if ( self::$schema )
			return static::$schema;
		
		return static::$schema= static::getSchema(array(
			'values' => self::getParams(array('default' => null, 'null' => true)),
			'default' => ElementBoolean::getParams(array('default' => null, 'null' => true)),
			'null' => ElementBoolean::getParams(array('default' => true, 'null' => true))
		));
		
	}
	
	public static function getSchema ( $params = array() ) {
		
		$params['type'] = 'set';
		return $params;
		
	}
	
	public static function invalid ( $schema, $value, $data = array() ) {
		
		if ( $error = parent::invalid($value, $data) )
			return $error;
		
		if ( is_null($value) || is_array($value) )
			return false;
		
		return 'Value is not a set !';
		
	}
	
}

?>