<?php

/**
 * Framework class for strings that involve multiple values.
 *
 * Certain CSS properties such as border-width and margin allow multiple
 * lengths to be specified.  This class can take a vanilla border-width
 * definition and multiply it, usually into a max of four.
 *
 * @note Even though the CSS specification isn't clear about it, inherit
 *       can only be used alone: it will never manifest as part of a multi
 *       shorthand declaration.  Thus, this class does not allow inherit.
 */
class HTMLPurifier_AttrDef_CSS_Multiple extends HTMLPurifier_AttrDef {
	/**
	 * Instance of component definition to defer validation to.
	 * @type HTMLPurifier_AttrDef
	 * 
	 * @todo Make protected
	 */
	public $single;
	
	/**
	 * Max number of values allowed.
	 * 
	 * @todo Make protected
	 */
	public $max;
	
	/**
	 *
	 * @param HTMLPurifier_AttrDef $single
	 *        	HTMLPurifier_AttrDef to multiply
	 * @param int $max
	 *        	Max number of values allowed (usually four)
	 */
	public function __construct($single, $max = 4) {
		$this->single = $single;
		$this->max = $max;
	}
	
	/**
	 *
	 * @param string $string        	
	 * @param HTMLPurifier_Config $config        	
	 * @param HTMLPurifier_Context $context        	
	 * @return bool|string
	 */
	public function validate($string, $config, $context) {
		$string = $this->parseCDATA ( $string );
		if ($string === '') {
			return false;
		}
		$parts = explode ( ' ', $string ); // parseCDATA replaced \r, \t and \n
		$length = count ( $parts );
		$final = '';
		for($i = 0, $num = 0; $i < $length && $num < $this->max; $i ++) {
			if (ctype_space ( $parts [$i] )) {
				continue;
			}
			$result = $this->single->validate ( $parts [$i], $config, $context );
			if ($result !== false) {
				$final .= $result . ' ';
				$num ++;
			}
		}
		if ($final === '') {
			return false;
		}
		return rtrim ( $final );
	}
}

// vim: et sw=4 sts=4