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Diffstat (limited to 'extlib/HTMLPurifier/HTMLPurifier/Length.php')
-rw-r--r-- | extlib/HTMLPurifier/HTMLPurifier/Length.php | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/extlib/HTMLPurifier/HTMLPurifier/Length.php b/extlib/HTMLPurifier/HTMLPurifier/Length.php new file mode 100644 index 000000000..8d2a46b7d --- /dev/null +++ b/extlib/HTMLPurifier/HTMLPurifier/Length.php @@ -0,0 +1,115 @@ +<?php + +/** + * Represents a measurable length, with a string numeric magnitude + * and a unit. This object is immutable. + */ +class HTMLPurifier_Length +{ + + /** + * String numeric magnitude. + */ + protected $n; + + /** + * String unit. False is permitted if $n = 0. + */ + protected $unit; + + /** + * Whether or not this length is valid. Null if not calculated yet. + */ + protected $isValid; + + /** + * Lookup array of units recognized by CSS 2.1 + */ + protected static $allowedUnits = array( + 'em' => true, 'ex' => true, 'px' => true, 'in' => true, + 'cm' => true, 'mm' => true, 'pt' => true, 'pc' => true + ); + + /** + * @param number $n Magnitude + * @param string $u Unit + */ + public function __construct($n = '0', $u = false) { + $this->n = (string) $n; + $this->unit = $u !== false ? (string) $u : false; + } + + /** + * @param string $s Unit string, like '2em' or '3.4in' + * @warning Does not perform validation. + */ + static public function make($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, $unit); + } + + /** + * Validates the number and unit. + */ + protected function validate() { + // Special case: + if ($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 = $result; + return true; + } + + /** + * Returns string representation of number. + */ + public function toString() { + if (!$this->isValid()) return false; + return $this->n . $this->unit; + } + + /** + * Retrieves string numeric magnitude. + */ + public function getN() {return $this->n;} + + /** + * Retrieves string unit. + */ + public function getUnit() {return $this->unit;} + + /** + * Returns true if this length unit is valid. + */ + public function isValid() { + if ($this->isValid === null) $this->isValid = $this->validate(); + return $this->isValid; + } + + /** + * Compares two lengths, and returns 1 if greater, -1 if less and 0 if equal. + * @warning If both values are too large or small, this calculation will + * not work properly + */ + public function compareTo($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 |