<?php

// Enum = Enumerated
/**
 * Validates a keyword against a list of valid values.
 * @warning The case-insensitive compare of this function uses PHP's
 * built-in strtolower and ctype_lower functions, which may
 * cause problems with international comparisons
 */
class HTMLPurifier_AttrDef_Enum extends HTMLPurifier_AttrDef {
	
	/**
	 * Lookup table of valid values.
	 * @type array
	 * 
	 * @todo Make protected
	 */
	public $valid_values = array ();
	
	/**
	 * Bool indicating whether or not enumeration is case sensitive.
	 * @note In general this is always case insensitive.
	 */
	protected $case_sensitive = false; // values according to W3C spec
	
	/**
	 *
	 * @param array $valid_values
	 *        	List of valid values
	 * @param bool $case_sensitive
	 *        	Whether or not case sensitive
	 */
	public function __construct($valid_values = array(), $case_sensitive = false) {
		$this->valid_values = array_flip ( $valid_values );
		$this->case_sensitive = $case_sensitive;
	}
	
	/**
	 *
	 * @param string $string        	
	 * @param HTMLPurifier_Config $config        	
	 * @param HTMLPurifier_Context $context        	
	 * @return bool|string
	 */
	public function validate($string, $config, $context) {
		$string = trim ( $string );
		if (! $this->case_sensitive) {
			// we may want to do full case-insensitive libraries
			$string = ctype_lower ( $string ) ? $string : strtolower ( $string );
		}
		$result = isset ( $this->valid_values [$string] );
		
		return $result ? $string : false;
	}
	
	/**
	 *
	 * @param string $string
	 *        	In form of comma-delimited list of case-insensitive
	 *        	valid values. Example: "foo,bar,baz". Prepend "s:" to make
	 *        	case sensitive
	 * @return HTMLPurifier_AttrDef_Enum
	 */
	public function make($string) {
		if (strlen ( $string ) > 2 && $string [0] == 's' && $string [1] == ':') {
			$string = substr ( $string, 2 );
			$sensitive = true;
		} else {
			$sensitive = false;
		}
		$values = explode ( ',', $string );
		return new HTMLPurifier_AttrDef_Enum ( $values, $sensitive );
	}
}

// vim: et sw=4 sts=4