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 validators
  11      * @type HTMLPurifier_AttrDef[]
  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     /**
  20      * @param HTMLPurifier_Config $config
  21      */
  22     public function __construct($config)
  23     {
  24         $def = $config->getCSSDefinition();
  25         $this->info['font-style'] = $def->info['font-style'];
  26         $this->info['font-variant'] = $def->info['font-variant'];
  27         $this->info['font-weight'] = $def->info['font-weight'];
  28         $this->info['font-size'] = $def->info['font-size'];
  29         $this->info['line-height'] = $def->info['line-height'];
  30         $this->info['font-family'] = $def->info['font-family'];
  31     }
  32
  33     /**
  34      * @param string $string
  35      * @param HTMLPurifier_Config $config
  36      * @param HTMLPurifier_Context $context
  37      * @return bool|string
  38      */
  39     public function validate($string, $config, $context)
  40     {
  41         static $system_fonts = array(
  42             'caption' => true,
  43             'icon' => true,
  44             'menu' => true,
  45             'message-box' => true,
  46             'small-caption' => true,
  47             'status-bar' => true
  48         );
  49
  50         // regular pre-processing
  51         $string = $this->parseCDATA($string);
  52         if ($string === '') {
  53             return false;
  54         }
  55
  56         // check if it's one of the keywords
  57         $lowercase_string = strtolower($string);
  58         if (isset($system_fonts[$lowercase_string])) {
  59             return $lowercase_string;
  60         }
  61
  62         $bits = explode(' ', $string); // bits to process
  63         $stage = 0; // this indicates what we're looking for
  64         $caught = array(); // which stage 0 properties have we caught?
  65         $stage_1 = array('font-style', 'font-variant', 'font-weight');
  66         $final = ''; // output
  67
  68         for ($i = 0, $size = count($bits); $i < $size; $i++) {
  69             if ($bits[$i] === '') {
  70                 continue;
  71             }
  72             switch ($stage) {
  73                 case 0: // attempting to catch font-style, font-variant or font-weight
  74                     foreach ($stage_1 as $validator_name) {
  75                         if (isset($caught[$validator_name])) {
  76                             continue;
  77                         }
  78                         $r = $this->info[$validator_name]->validate(
  79                             $bits[$i],
  80                             $config,
  81                             $context
  82                         );
  83                         if ($r !== false) {
  84                             $final .= $r . ' ';
  85                             $caught[$validator_name] = true;
  86                             break;
  87                         }
  88                     }
  89                     // all three caught, continue on
  90                     if (count($caught) >= 3) {
  91                         $stage = 1;
  92                     }
  93                     if ($r !== false) {
  94                         break;
  95                     }
  96                 case 1: // attempting to catch font-size and perhaps line-height
  97                     $found_slash = false;
  98                     if (strpos($bits[$i], '/') !== false) {
  99                         list($font_size, $line_height) =
 100                             explode('/', $bits[$i]);
 101                         if ($line_height === '') {
 102                             // ooh, there's a space after the slash!
 103                             $line_height = false;
 104                             $found_slash = true;
 105                         }
 106                     } else {
 107                         $font_size = $bits[$i];
 108                         $line_height = false;
 109                     }
 110                     $r = $this->info['font-size']->validate(
 111                         $font_size,
 112                         $config,
 113                         $context
 114                     );
 115                     if ($r !== false) {
 116                         $final .= $r;
 117                         // attempt to catch line-height
 118                         if ($line_height === false) {
 119                             // we need to scroll forward
 120                             for ($j = $i + 1; $j < $size; $j++) {
 121                                 if ($bits[$j] === '') {
 122                                     continue;
 123                                 }
 124                                 if ($bits[$j] === '/') {
 125                                     if ($found_slash) {
 126                                         return false;
 127                                     } else {
 128                                         $found_slash = true;
 129                                         continue;
 130                                     }
 131                                 }
 132                                 $line_height = $bits[$j];
 133                                 break;
 134                             }
 135                         } else {
 136                             // slash already found
 137                             $found_slash = true;
 138                             $j = $i;
 139                         }
 140                         if ($found_slash) {
 141                             $i = $j;
 142                             $r = $this->info['line-height']->validate(
 143                                 $line_height,
 144                                 $config,
 145                                 $context
 146                             );
 147                             if ($r !== false) {
 148                                 $final .= '/' . $r;
 149                             }
 150                         }
 151                         $final .= ' ';
 152                         $stage = 2;
 153                         break;
 154                     }
 155                     return false;
 156                 case 2: // attempting to catch font-family
 157                     $font_family =
 158                         implode(' ', array_slice($bits, $i, $size - $i));
 159                     $r = $this->info['font-family']->validate(
 160                         $font_family,
 161                         $config,
 162                         $context
 163                     );
 164                     if ($r !== false) {
 165                         $final .= $r . ' ';
 166                         // processing completed successfully
 167                         return rtrim($final);
 168                     }
 169                     return false;
 170             }
 171         }
 172         return false;
 173     }
 174 }
 175
 176 // vim: et sw=4 sts=4