library/HTMLPurifier/AttrDef/CSS/Font.php

   1 <?php
   2
   3 /**
   4  * Validates shorthand CSS property font.
   5  */
   6 class HTMLPurifier_AttrDef_CSS_Font extends HTMLPurifier_AttrDef
   7 {
   8
   9     /**
  10      * Local copy of component validators.
  11      *
  12      * @note If we moved specific CSS property definitions to their own
  13      *       classes instead of having them be assembled at run time by
  14      *       CSSDefinition, this wouldn't be necessary.  We'd instantiate
  15      *       our own copies.
  16      */
  17     protected $info = array();
  18
  19     public function __construct($config) {
  20         $def = $config->getCSSDefinition();
  21         $this->info['font-style']   = $def->info['font-style'];
  22         $this->info['font-variant'] = $def->info['font-variant'];
  23         $this->info['font-weight']  = $def->info['font-weight'];
  24         $this->info['font-size']    = $def->info['font-size'];
  25         $this->info['line-height']  = $def->info['line-height'];
  26         $this->info['font-family']  = $def->info['font-family'];
  27     }
  28
  29     public function validate($string, $config, $context) {
  30
  31         static $system_fonts = array(
  32             'caption' => true,
  33             'icon' => true,
  34             'menu' => true,
  35             'message-box' => true,
  36             'small-caption' => true,
  37             'status-bar' => true
  38         );
  39
  40         // regular pre-processing
  41         $string = $this->parseCDATA($string);
  42         if ($string === '') return false;
  43
  44         // check if it's one of the keywords
  45         $lowercase_string = strtolower($string);
  46         if (isset($system_fonts[$lowercase_string])) {
  47             return $lowercase_string;
  48         }
  49
  50         $bits = explode(' ', $string); // bits to process
  51         $stage = 0; // this indicates what we're looking for
  52         $caught = array(); // which stage 0 properties have we caught?
  53         $stage_1 = array('font-style', 'font-variant', 'font-weight');
  54         $final = ''; // output
  55
  56         for ($i = 0, $size = count($bits); $i < $size; $i++) {
  57             if ($bits[$i] === '') continue;
  58             switch ($stage) {
  59
  60                 // attempting to catch font-style, font-variant or font-weight
  61                 case 0:
  62                     foreach ($stage_1 as $validator_name) {
  63                         if (isset($caught[$validator_name])) continue;
  64                         $r = $this->info[$validator_name]->validate(
  65                                                 $bits[$i], $config, $context);
  66                         if ($r !== false) {
  67                             $final .= $r . ' ';
  68                             $caught[$validator_name] = true;
  69                             break;
  70                         }
  71                     }
  72                     // all three caught, continue on
  73                     if (count($caught) >= 3) $stage = 1;
  74                     if ($r !== false) break;
  75
  76                 // attempting to catch font-size and perhaps line-height
  77                 case 1:
  78                     $found_slash = false;
  79                     if (strpos($bits[$i], '/') !== false) {
  80                         list($font_size, $line_height) =
  81                                                     explode('/', $bits[$i]);
  82                         if ($line_height === '') {
  83                             // ooh, there's a space after the slash!
  84                             $line_height = false;
  85                             $found_slash = true;
  86                         }
  87                     } else {
  88                         $font_size = $bits[$i];
  89                         $line_height = false;
  90                     }
  91                     $r = $this->info['font-size']->validate(
  92                                               $font_size, $config, $context);
  93                     if ($r !== false) {
  94                         $final .= $r;
  95                         // attempt to catch line-height
  96                         if ($line_height === false) {
  97                             // we need to scroll forward
  98                             for ($j = $i + 1; $j < $size; $j++) {
  99                                 if ($bits[$j] === '') continue;
 100                                 if ($bits[$j] === '/') {
 101                                     if ($found_slash) {
 102                                         return false;
 103                                     } else {
 104                                         $found_slash = true;
 105                                         continue;
 106                                     }
 107                                 }
 108                                 $line_height = $bits[$j];
 109                                 break;
 110                             }
 111                         } else {
 112                             // slash already found
 113                             $found_slash = true;
 114                             $j = $i;
 115                         }
 116                         if ($found_slash) {
 117                             $i = $j;
 118                             $r = $this->info['line-height']->validate(
 119                                               $line_height, $config, $context);
 120                             if ($r !== false) {
 121                                 $final .= '/' . $r;
 122                             }
 123                         }
 124                         $final .= ' ';
 125                         $stage = 2;
 126                         break;
 127                     }
 128                     return false;
 129
 130                 // attempting to catch font-family
 131                 case 2:
 132                     $font_family =
 133                         implode(' ', array_slice($bits, $i, $size - $i));
 134                     $r = $this->info['font-family']->validate(
 135                                               $font_family, $config, $context);
 136                     if ($r !== false) {
 137                         $final .= $r . ' ';
 138                         // processing completed successfully
 139                         return rtrim($final);
 140                     }
 141                     return false;
 142             }
 143         }
 144         return false;
 145     }
 146
 147 }
 148
 149 // vim: et sw=4 sts=4