File indexing completed on 2024-12-22 05:36:21

 <?php
 
 /**
  * Represents a measurable length, with a string numeric magnitude
  * and a unit. This object is immutable.
  */
 class HTMLPurifier_Length
 {
 
     /**
      * String numeric magnitude.
      * @type string
      */
     protected $n;
 
     /**
      * String unit. False is permitted if $n = 0.
      * @type string|bool
      */
     protected $unit;
 
     /**
      * Whether or not this length is valid. Null if not calculated yet.
      * @type bool
      */
     protected $isValid;
 
     /**
      * Array Lookup array of units recognized by CSS 2.1
      * @type array
      */
     protected static $allowedUnits = array(
         'em' => true, 'ex' => true, 'px' => true, 'in' => true,
         'cm' => true, 'mm' => true, 'pt' => true, 'pc' => true
     );
 
     /**
      * @param string $n Magnitude
      * @param bool|string $u Unit
      */
     public function __construct($n = '0', $u = false)
     {
         $this->n = (string) $n;
         $this->unit = $u !== false ? (string) $u : false;
     }
 
     /**
      * @param string $s Unit string, like '2em' or '3.4in'
      * @return HTMLPurifier_Length
      * @warning Does not perform validation.
      */
     public static function make($s)
     {
         if ($s instanceof HTMLPurifier_Length) {
             return $s;
         }
         $n_length = strspn($s, '1234567890.+-');
         $n = substr($s, 0, $n_length);
         $unit = substr($s, $n_length);
         if ($unit === '') {
             $unit = false;
         }
         return new HTMLPurifier_Length($n, $unit);
     }
 
     /**
      * Validates the number and unit.
      * @return bool
      */
     protected function validate()
     {
         // Special case:
         if ($this->n === '+0' || $this->n === '-0') {
             $this->n = '0';
         }
         if ($this->n === '0' && $this->unit === false) {
             return true;
         }
         if (!ctype_lower($this->unit)) {
             $this->unit = strtolower($this->unit);
         }
         if (!isset(HTMLPurifier_Length::$allowedUnits[$this->unit])) {
             return false;
         }
         // Hack:
         $def = new HTMLPurifier_AttrDef_CSS_Number();
         $result = $def->validate($this->n, false, false);
         if ($result === false) {
             return false;
         }
         $this->n = $result;
         return true;
     }
 
     /**
      * Returns string representation of number.
      * @return string
      */
     public function toString()
     {
         if (!$this->isValid()) {
             return false;
         }
         return $this->n . $this->unit;
     }
 
     /**
      * Retrieves string numeric magnitude.
      * @return string
      */
     public function getN()
     {
         return $this->n;
     }
 
     /**
      * Retrieves string unit.
      * @return string
      */
     public function getUnit()
     {
         return $this->unit;
     }
 
     /**
      * Returns true if this length unit is valid.
      * @return bool
      */
     public function isValid()
     {
         if ($this->isValid === null) {
             $this->isValid = $this->validate();
         }
         return $this->isValid;
     }
 
     /**
      * Compares two lengths, and returns 1 if greater, -1 if less and 0 if equal.
      * @param HTMLPurifier_Length $l
      * @return int
      * @warning If both values are too large or small, this calculation will
      *          not work properly
      */
     public function compareTo($l)
     {
         if ($l === false) {
             return false;
         }
         if ($l->unit !== $this->unit) {
             $converter = new HTMLPurifier_UnitConverter();
             $l = $converter->convert($l, $this->unit);
             if ($l === false) {
                 return false;
             }
         }
         return $this->n - $l->n;
     }
 }
 
 // vim: et sw=4 sts=4