includes/Html.php

   1 <?php
   2 /**
   3  * Collection of methods to generate HTML content
   4  *
   5  * Copyright © 2009 Aryeh Gregor
   6  * http://www.mediawiki.org/
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with this program; if not, write to the Free Software Foundation, Inc.,
  20  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  21  * http://www.gnu.org/copyleft/gpl.html
  22  *
  23  * @file
  24  */
  25
  26 /**
  27  * This class is a collection of static functions that serve two purposes:
  28  *
  29  * 1) Implement any algorithms specified by HTML5, or other HTML
  30  * specifications, in a convenient and self-contained way.
  31  *
  32  * 2) Allow HTML elements to be conveniently and safely generated, like the
  33  * current Xml class but a) less confused (Xml supports HTML-specific things,
  34  * but only sometimes!) and b) not necessarily confined to XML-compatible
  35  * output.
  36  *
  37  * There are two important configuration options this class uses:
  38  *
  39  * $wgHtml5: If this is set to false, then all output should be valid XHTML 1.0
  40  *     Transitional.
  41  * $wgWellFormedXml: If this is set to true, then all output should be
  42  *     well-formed XML (quotes on attributes, self-closing tags, etc.).
  43  *
  44  * This class is meant to be confined to utility functions that are called from
  45  * trusted code paths.  It does not do enforcement of policy like not allowing
  46  * <a> elements.
  47  *
  48  * @since 1.16
  49  */
  50 class Html {
  51         # List of void elements from HTML5, section 8.1.2 as of 2011-08-12
  52         private static $voidElements = array(
  53                 'area',
  54                 'base',
  55                 'br',
  56                 'col',
  57                 'command',
  58                 'embed',
  59                 'hr',
  60                 'img',
  61                 'input',
  62                 'keygen',
  63                 'link',
  64                 'meta',
  65                 'param',
  66                 'source',
  67                 'track',
  68                 'wbr',
  69         );
  70
  71         # Boolean attributes, which may have the value omitted entirely.  Manually
  72         # collected from the HTML5 spec as of 2011-08-12.
  73         private static $boolAttribs = array(
  74                 'async',
  75                 'autofocus',
  76                 'autoplay',
  77                 'checked',
  78                 'controls',
  79                 'default',
  80                 'defer',
  81                 'disabled',
  82                 'formnovalidate',
  83                 'hidden',
  84                 'ismap',
  85                 'itemscope',
  86                 'loop',
  87                 'multiple',
  88                 'muted',
  89                 'novalidate',
  90                 'open',
  91                 'pubdate',
  92                 'readonly',
  93                 'required',
  94                 'reversed',
  95                 'scoped',
  96                 'seamless',
  97                 'selected',
  98                 'truespeed',
  99                 'typemustmatch',
 100                 # HTML5 Microdata
 101                 'itemscope',
 102         );
 103
 104         /**
 105          * Returns an HTML element in a string.  The major advantage here over
 106          * manually typing out the HTML is that it will escape all attribute
 107          * values.  If you're hardcoding all the attributes, or there are none, you
 108          * should probably type out the string yourself.
 109          *
 110          * This is quite similar to Xml::tags(), but it implements some useful
 111          * HTML-specific logic.  For instance, there is no $allowShortTag
 112          * parameter: the closing tag is magically omitted if $element has an empty
 113          * content model.  If $wgWellFormedXml is false, then a few bytes will be
 114          * shaved off the HTML output as well.  In the future, other HTML-specific
 115          * features might be added, like allowing arrays for the values of
 116          * attributes like class= and media=.
 117          *
 118          * @param $element string The element's name, e.g., 'a'
 119          * @param $attribs array  Associative array of attributes, e.g., array(
 120          *   'href' => 'http://www.mediawiki.org/' ).  See expandAttributes() for
 121          *   further documentation.
 122          * @param $contents string The raw HTML contents of the element: *not*
 123          *   escaped!
 124          * @return string Raw HTML
 125          */
 126         public static function rawElement( $element, $attribs = array(), $contents = '' ) {
 127                 global $wgWellFormedXml;
 128                 $start = self::openElement( $element, $attribs );
 129                 if ( in_array( $element, self::$voidElements ) ) {
 130                         if ( $wgWellFormedXml ) {
 131                                 # Silly XML.
 132                                 return substr( $start, 0, -1 ) . ' />';
 133                         }
 134                         return $start;
 135                 } else {
 136                         return "$start$contents" . self::closeElement( $element );
 137                 }
 138         }
 139
 140         /**
 141          * Identical to rawElement(), but HTML-escapes $contents (like
 142          * Xml::element()).
 143          *
 144          * @param $element string
 145          * @param $attribs array
 146          * @param $contents string
 147          *
 148          * @return string
 149          */
 150         public static function element( $element, $attribs = array(), $contents = '' ) {
 151                 return self::rawElement( $element, $attribs, strtr( $contents, array(
 152                         # There's no point in escaping quotes, >, etc. in the contents of
 153                         # elements.
 154                         '&' => '&amp;',
 155                         '<' => '&lt;'
 156                 ) ) );
 157         }
 158
 159         /**
 160          * Identical to rawElement(), but has no third parameter and omits the end
 161          * tag (and the self-closing '/' in XML mode for empty elements).
 162          *
 163          * @param $element string
 164          * @param $attribs array
 165          *
 166          * @return string
 167          */
 168         public static function openElement( $element, $attribs = array() ) {
 169                 global $wgHtml5, $wgWellFormedXml;
 170                 $attribs = (array)$attribs;
 171                 # This is not required in HTML5, but let's do it anyway, for
 172                 # consistency and better compression.
 173                 $element = strtolower( $element );
 174
 175                 # In text/html, initial <html> and <head> tags can be omitted under
 176                 # pretty much any sane circumstances, if they have no attributes.  See:
 177                 # <http://www.whatwg.org/specs/web-apps/current-work/multipage/syntax.html#optional-tags>
 178                 if ( !$wgWellFormedXml && !$attribs
 179                 && in_array( $element, array( 'html', 'head' ) ) ) {
 180                         return '';
 181                 }
 182
 183                 # Remove HTML5-only attributes if we aren't doing HTML5, and disable
 184                 # form validation regardless (see bug 23769 and the more detailed
 185                 # comment in expandAttributes())
 186                 if ( $element == 'input' ) {
 187                         # Whitelist of types that don't cause validation.  All except
 188                         # 'search' are valid in XHTML1.
 189                         $validTypes = array(
 190                                 'hidden',
 191                                 'text',
 192                                 'password',
 193                                 'checkbox',
 194                                 'radio',
 195                                 'file',
 196                                 'submit',
 197                                 'image',
 198                                 'reset',
 199                                 'button',
 200                                 'search',
 201                         );
 202
 203                         if ( isset( $attribs['type'] )
 204                         && !in_array( $attribs['type'], $validTypes ) ) {
 205                                 unset( $attribs['type'] );
 206                         }
 207
 208                         if ( isset( $attribs['type'] ) && $attribs['type'] == 'search'
 209                         && !$wgHtml5 ) {
 210                                 unset( $attribs['type'] );
 211                         }
 212                 }
 213
 214                 if ( !$wgHtml5 && $element == 'textarea' && isset( $attribs['maxlength'] ) ) {
 215                         unset( $attribs['maxlength'] );
 216                 }
 217
 218                 return "<$element" . self::expandAttributes(
 219                         self::dropDefaults( $element, $attribs ) ) . '>';
 220         }
 221
 222         /**
 223          * Returns "</$element>", except if $wgWellFormedXml is off, in which case
 224          * it returns the empty string when that's guaranteed to be safe.
 225          *
 226          * @since 1.17
 227          * @param $element string Name of the element, e.g., 'a'
 228          * @return string A closing tag, if required
 229          */
 230         public static function closeElement( $element ) {
 231                 global $wgWellFormedXml;
 232
 233                 $element = strtolower( $element );
 234
 235                 # Reference:
 236                 # http://www.whatwg.org/specs/web-apps/current-work/multipage/syntax.html#optional-tags
 237                 if ( !$wgWellFormedXml && in_array( $element, array(
 238                         'html',
 239                         'head',
 240                         'body',
 241                         'li',
 242                         'dt',
 243                         'dd',
 244                         'tr',
 245                         'td',
 246                         'th',
 247                 ) ) ) {
 248                         return '';
 249                 }
 250                 return "</$element>";
 251         }
 252
 253         /**
 254          * Given an element name and an associative array of element attributes,
 255          * return an array that is functionally identical to the input array, but
 256          * possibly smaller.  In particular, attributes might be stripped if they
 257          * are given their default values.
 258          *
 259          * This method is not guaranteed to remove all redundant attributes, only
 260          * some common ones and some others selected arbitrarily at random.  It
 261          * only guarantees that the output array should be functionally identical
 262          * to the input array (currently per the HTML 5 draft as of 2009-09-06).
 263          *
 264          * @param $element string Name of the element, e.g., 'a'
 265          * @param $attribs array  Associative array of attributes, e.g., array(
 266          *   'href' => 'http://www.mediawiki.org/' ).  See expandAttributes() for
 267          *   further documentation.
 268          * @return array An array of attributes functionally identical to $attribs
 269          */
 270         private static function dropDefaults( $element, $attribs ) {
 271                 # Don't bother doing anything if we aren't outputting HTML5; it's too
 272                 # much of a pain to maintain two sets of defaults.
 273                 global $wgHtml5;
 274                 if ( !$wgHtml5 ) {
 275                         return $attribs;
 276                 }
 277
 278                 static $attribDefaults = array(
 279                         'area' => array( 'shape' => 'rect' ),
 280                         'button' => array(
 281                                 'formaction' => 'GET',
 282                                 'formenctype' => 'application/x-www-form-urlencoded',
 283                                 'type' => 'submit',
 284                         ),
 285                         'canvas' => array(
 286                                 'height' => '150',
 287                                 'width' => '300',
 288                         ),
 289                         'command' => array( 'type' => 'command' ),
 290                         'form' => array(
 291                                 'action' => 'GET',
 292                                 'autocomplete' => 'on',
 293                                 'enctype' => 'application/x-www-form-urlencoded',
 294                         ),
 295                         'input' => array(
 296                                 'formaction' => 'GET',
 297                                 'type' => 'text',
 298                                 'value' => '',
 299                         ),
 300                         'keygen' => array( 'keytype' => 'rsa' ),
 301                         'link' => array( 'media' => 'all' ),
 302                         'menu' => array( 'type' => 'list' ),
 303                         # Note: the use of text/javascript here instead of other JavaScript
 304                         # MIME types follows the HTML5 spec.
 305                         'script' => array( 'type' => 'text/javascript' ),
 306                         'style' => array(
 307                                 'media' => 'all',
 308                                 'type' => 'text/css',
 309                         ),
 310                         'textarea' => array( 'wrap' => 'soft' ),
 311                 );
 312
 313                 $element = strtolower( $element );
 314
 315                 foreach ( $attribs as $attrib => $value ) {
 316                         $lcattrib = strtolower( $attrib );
 317                         $value = strval( $value );
 318
 319                         # Simple checks using $attribDefaults
 320                         if ( isset( $attribDefaults[$element][$lcattrib] ) &&
 321                         $attribDefaults[$element][$lcattrib] == $value ) {
 322                                 unset( $attribs[$attrib] );
 323                         }
 324
 325                         if ( $lcattrib == 'class' && $value == '' ) {
 326                                 unset( $attribs[$attrib] );
 327                         }
 328                 }
 329
 330                 # More subtle checks
 331                 if ( $element === 'link' && isset( $attribs['type'] )
 332                 && strval( $attribs['type'] ) == 'text/css' ) {
 333                         unset( $attribs['type'] );
 334                 }
 335                 if ( $element === 'select' && isset( $attribs['size'] ) ) {
 336                         if ( in_array( 'multiple', $attribs )
 337                                 || ( isset( $attribs['multiple'] ) && $attribs['multiple'] !== false )
 338                         ) {
 339                                 # A multi-select
 340                                 if ( strval( $attribs['size'] ) == '4' ) {
 341                                         unset( $attribs['size'] );
 342                                 }
 343                         } else {
 344                                 # Single select
 345                                 if ( strval( $attribs['size'] ) == '1' ) {
 346                                         unset( $attribs['size'] );
 347                                 }
 348                         }
 349                 }
 350
 351                 return $attribs;
 352         }
 353
 354         /**
 355          * Given an associative array of element attributes, generate a string
 356          * to stick after the element name in HTML output.  Like array( 'href' =>
 357          * 'http://www.mediawiki.org/' ) becomes something like
 358          * ' href="http://www.mediawiki.org"'.  Again, this is like
 359          * Xml::expandAttributes(), but it implements some HTML-specific logic.
 360          * For instance, it will omit quotation marks if $wgWellFormedXml is false,
 361          * and will treat boolean attributes specially.
 362          *
 363          * @param $attribs array Associative array of attributes, e.g., array(
 364          *   'href' => 'http://www.mediawiki.org/' ).  Values will be HTML-escaped.
 365          *   A value of false means to omit the attribute.  For boolean attributes,
 366          *   you can omit the key, e.g., array( 'checked' ) instead of
 367          *   array( 'checked' => 'checked' ) or such.
 368          * @return string HTML fragment that goes between element name and '>'
 369          *   (starting with a space if at least one attribute is output)
 370          */
 371         public static function expandAttributes( $attribs ) {
 372                 global $wgHtml5, $wgWellFormedXml;
 373
 374                 $ret = '';
 375                 $attribs = (array)$attribs;
 376                 foreach ( $attribs as $key => $value ) {
 377                         if ( $value === false || is_null( $value ) ) {
 378                                 continue;
 379                         }
 380
 381                         # For boolean attributes, support array( 'foo' ) instead of
 382                         # requiring array( 'foo' => 'meaningless' ).
 383                         if ( is_int( $key )
 384                         && in_array( strtolower( $value ), self::$boolAttribs ) ) {
 385                                 $key = $value;
 386                         }
 387
 388                         # Not technically required in HTML5, but required in XHTML 1.0,
 389                         # and we'd like consistency and better compression anyway.
 390                         $key = strtolower( $key );
 391
 392                         # Bug 23769: Blacklist all form validation attributes for now.  Current
 393                         # (June 2010) WebKit has no UI, so the form just refuses to submit
 394                         # without telling the user why, which is much worse than failing
 395                         # server-side validation.  Opera is the only other implementation at
 396                         # this time, and has ugly UI, so just kill the feature entirely until
 397                         # we have at least one good implementation.
 398                         if ( in_array( $key, array( 'max', 'min', 'pattern', 'required', 'step' ) ) ) {
 399                                 continue;
 400                         }
 401
 402                         # Here we're blacklisting some HTML5-only attributes...
 403                         if ( !$wgHtml5 && in_array( $key, array(
 404                                         'autocomplete',
 405                                         'autofocus',
 406                                         'max',
 407                                         'min',
 408                                         'multiple',
 409                                         'pattern',
 410                                         'placeholder',
 411                                         'required',
 412                                         'step',
 413                                         'spellcheck',
 414                         ) ) ) {
 415                                 continue;
 416                         }
 417
 418                         # See the "Attributes" section in the HTML syntax part of HTML5,
 419                         # 9.1.2.3 as of 2009-08-10.  Most attributes can have quotation
 420                         # marks omitted, but not all.  (Although a literal " is not
 421                         # permitted, we don't check for that, since it will be escaped
 422                         # anyway.)
 423                         #
 424                         # See also research done on further characters that need to be
 425                         # escaped: http://code.google.com/p/html5lib/issues/detail?id=93
 426                         $badChars = "\\x00- '=<>`/\x{00a0}\x{1680}\x{180e}\x{180F}\x{2000}\x{2001}"
 427                                 . "\x{2002}\x{2003}\x{2004}\x{2005}\x{2006}\x{2007}\x{2008}\x{2009}"
 428                                 . "\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}";
 429                         if ( $wgWellFormedXml || $value === ''
 430                         || preg_match( "![$badChars]!u", $value ) ) {
 431                                 $quote = '"';
 432                         } else {
 433                                 $quote = '';
 434                         }
 435
 436                         if ( in_array( $key, self::$boolAttribs ) ) {
 437                                 # In XHTML 1.0 Transitional, the value needs to be equal to the
 438                                 # key.  In HTML5, we can leave the value empty instead.  If we
 439                                 # don't need well-formed XML, we can omit the = entirely.
 440                                 if ( !$wgWellFormedXml ) {
 441                                         $ret .= " $key";
 442                                 } elseif ( $wgHtml5 ) {
 443                                         $ret .= " $key=\"\"";
 444                                 } else {
 445                                         $ret .= " $key=\"$key\"";
 446                                 }
 447                         } else {
 448                                 # Apparently we need to entity-encode \n, \r, \t, although the
 449                                 # spec doesn't mention that.  Since we're doing strtr() anyway,
 450                                 # and we don't need <> escaped here, we may as well not call
 451                                 # htmlspecialchars().
 452                                 # @todo FIXME: Verify that we actually need to
 453                                 # escape \n\r\t here, and explain why, exactly.
 454                                 #
 455                                 # We could call Sanitizer::encodeAttribute() for this, but we
 456                                 # don't because we're stubborn and like our marginal savings on
 457                                 # byte size from not having to encode unnecessary quotes.
 458                                 $map = array(
 459                                         '&' => '&amp;',
 460                                         '"' => '&quot;',
 461                                         "\n" => '&#10;',
 462                                         "\r" => '&#13;',
 463                                         "\t" => '&#9;'
 464                                 );
 465                                 if ( $wgWellFormedXml ) {
 466                                         # This is allowed per spec: <http://www.w3.org/TR/xml/#NT-AttValue>
 467                                         # But reportedly it breaks some XML tools?
 468                                         # @todo FIXME: Is this really true?
 469                                         $map['<'] = '&lt;';
 470                                 }
 471                                 $ret .= " $key=$quote" . strtr( $value, $map ) . $quote;
 472                         }
 473                 }
 474                 return $ret;
 475         }
 476
 477         /**
 478          * Output a <script> tag with the given contents.  TODO: do some useful
 479          * escaping as well, like if $contents contains literal '</script>' or (for
 480          * XML) literal "]]>".
 481          *
 482          * @param $contents string JavaScript
 483          * @return string Raw HTML
 484          */
 485         public static function inlineScript( $contents ) {
 486                 global $wgHtml5, $wgJsMimeType, $wgWellFormedXml;
 487
 488                 $attrs = array();
 489
 490                 if ( !$wgHtml5 ) {
 491                         $attrs['type'] = $wgJsMimeType;
 492                 }
 493
 494                 if ( $wgWellFormedXml && preg_match( '/[<&]/', $contents ) ) {
 495                         $contents = "/*<![CDATA[*/$contents/*]]>*/";
 496                 }
 497
 498                 return self::rawElement( 'script', $attrs, $contents );
 499         }
 500
 501         /**
 502          * Output a <script> tag linking to the given URL, e.g.,
 503          * <script src=foo.js></script>.
 504          *
 505          * @param $url string
 506          * @return string Raw HTML
 507          */
 508         public static function linkedScript( $url ) {
 509                 global $wgHtml5, $wgJsMimeType;
 510
 511                 $attrs = array( 'src' => $url );
 512
 513                 if ( !$wgHtml5 ) {
 514                         $attrs['type'] = $wgJsMimeType;
 515                 }
 516
 517                 return self::element( 'script', $attrs );
 518         }
 519
 520         /**
 521          * Output a <style> tag with the given contents for the given media type
 522          * (if any).  TODO: do some useful escaping as well, like if $contents
 523          * contains literal '</style>' (admittedly unlikely).
 524          *
 525          * @param $contents string CSS
 526          * @param $media mixed A media type string, like 'screen'
 527          * @return string Raw HTML
 528          */
 529         public static function inlineStyle( $contents, $media = 'all' ) {
 530                 global $wgWellFormedXml;
 531
 532                 if ( $wgWellFormedXml && preg_match( '/[<&]/', $contents ) ) {
 533                         $contents = "/*<![CDATA[*/$contents/*]]>*/";
 534                 }
 535
 536                 return self::rawElement( 'style', array(
 537                         'type' => 'text/css',
 538                         'media' => $media,
 539                 ), $contents );
 540         }
 541
 542         /**
 543          * Output a <link rel=stylesheet> linking to the given URL for the given
 544          * media type (if any).
 545          *
 546          * @param $url string
 547          * @param $media mixed A media type string, like 'screen'
 548          * @return string Raw HTML
 549          */
 550         public static function linkedStyle( $url, $media = 'all' ) {
 551                 return self::element( 'link', array(
 552                         'rel' => 'stylesheet',
 553                         'href' => $url,
 554                         'type' => 'text/css',
 555                         'media' => $media,
 556                 ) );
 557         }
 558
 559         /**
 560          * Convenience function to produce an <input> element.  This supports the
 561          * new HTML5 input types and attributes, and will silently strip them if
 562          * $wgHtml5 is false.
 563          *
 564          * @param $name    string name attribute
 565          * @param $value   mixed  value attribute
 566          * @param $type    string type attribute
 567          * @param $attribs array  Associative array of miscellaneous extra
 568          *   attributes, passed to Html::element()
 569          * @return string Raw HTML
 570          */
 571         public static function input( $name, $value = '', $type = 'text', $attribs = array() ) {
 572                 $attribs['type'] = $type;
 573                 $attribs['value'] = $value;
 574                 $attribs['name'] = $name;
 575
 576                 return self::element( 'input', $attribs );
 577         }
 578
 579         /**
 580          * Convenience function to produce an input element with type=hidden
 581          *
 582          * @param $name    string name attribute
 583          * @param $value   string value attribute
 584          * @param $attribs array  Associative array of miscellaneous extra
 585          *   attributes, passed to Html::element()
 586          * @return string Raw HTML
 587          */
 588         public static function hidden( $name, $value, $attribs = array() ) {
 589                 return self::input( $name, $value, 'hidden', $attribs );
 590         }
 591
 592         /**
 593          * Convenience function to produce an <input> element.  This supports leaving
 594          * out the cols= and rows= which Xml requires and are required by HTML4/XHTML
 595          * but not required by HTML5 and will silently set cols="" and rows="" if
 596          * $wgHtml5 is false and cols and rows are omitted (HTML4 validates present
 597          * but empty cols="" and rows="" as valid).
 598          *
 599          * @param $name    string name attribute
 600          * @param $value   string value attribute
 601          * @param $attribs array  Associative array of miscellaneous extra
 602          *   attributes, passed to Html::element()
 603          * @return string Raw HTML
 604          */
 605         public static function textarea( $name, $value = '', $attribs = array() ) {
 606                 global $wgHtml5;
 607
 608                 $attribs['name'] = $name;
 609
 610                 if ( !$wgHtml5 ) {
 611                         if ( !isset( $attribs['cols'] ) ) {
 612                                 $attribs['cols'] = "";
 613                         }
 614
 615                         if ( !isset( $attribs['rows'] ) ) {
 616                                 $attribs['rows'] = "";
 617                         }
 618                 }
 619
 620                 return self::element( 'textarea', $attribs, $value );
 621         }
 622
 623         /**
 624          * Constructs the opening html-tag with necessary doctypes depending on
 625          * global variables.
 626          *
 627          * @param $attribs array  Associative array of miscellaneous extra
 628          *   attributes, passed to Html::element() of html tag.
 629          * @return string  Raw HTML
 630          */
 631         public static function htmlHeader( $attribs = array() ) {
 632                 $ret = '';
 633
 634                 global $wgMimeType;
 635
 636                 if ( self::isXmlMimeType( $wgMimeType ) ) {
 637                         $ret .= "<?xml version=\"1.0\" encoding=\"UTF-8\" ?" . ">\n";
 638                 }
 639
 640                 global $wgHtml5, $wgHtml5Version, $wgDocType, $wgDTD;
 641                 global $wgXhtmlNamespaces, $wgXhtmlDefaultNamespace;
 642
 643                 if ( $wgHtml5 ) {
 644                         $ret .= "<!DOCTYPE html>\n";
 645
 646                         if ( $wgHtml5Version ) {
 647                                 $attribs['version'] = $wgHtml5Version;
 648                         }
 649                 } else {
 650                         $ret .= "<!DOCTYPE html PUBLIC \"$wgDocType\" \"$wgDTD\">\n";
 651                         $attribs['xmlns'] = $wgXhtmlDefaultNamespace;
 652
 653                         foreach ( $wgXhtmlNamespaces as $tag => $ns ) {
 654                                 $attribs["xmlns:$tag"] = $ns;
 655                         }
 656                 }
 657
 658                 $html = Html::openElement( 'html', $attribs );
 659
 660                 if ( $html ) {
 661                         $html .= "\n";
 662                 }
 663
 664                 $ret .= $html;
 665
 666                 return $ret;
 667         }
 668
 669         /**
 670          * Determines if the given mime type is xml.
 671          *
 672          * @param $mimetype    string MimeType
 673          * @return Boolean
 674          */
 675         public static function isXmlMimeType( $mimetype ) {
 676                 switch ( $mimetype ) {
 677                         case 'text/xml':
 678                         case 'application/xhtml+xml':
 679                         case 'application/xml':
 680                                 return true;
 681                         default:
 682                                 return false;
 683                 }
 684         }
 685
 686         /**
 687          * Get HTML for an info box with an icon.
 688          *
 689          * @param $text String: wikitext, get this with wfMsgNoTrans()
 690          * @param $icon String: icon name, file in skins/common/images
 691          * @param $alt String: alternate text for the icon
 692          * @param $class String: additional class name to add to the wrapper div
 693          * @param $useStylePath
 694          *
 695          * @return string
 696          */
 697         static function infoBox( $text, $icon, $alt, $class = false, $useStylePath = true ) {
 698                 global $wgStylePath;
 699
 700                 if ( $useStylePath ) {
 701                         $icon = $wgStylePath.'/common/images/'.$icon;
 702                 }
 703
 704                 $s  = Html::openElement( 'div', array( 'class' => "mw-infobox $class") );
 705
 706                 $s .= Html::openElement( 'div', array( 'class' => 'mw-infobox-left' ) ).
 707                                 Html::element( 'img',
 708                                         array(
 709                                                 'src' => $icon,
 710                                                 'alt' => $alt,
 711                                         )
 712                                 ).
 713                                 Html::closeElement( 'div' );
 714
 715                 $s .= Html::openElement( 'div', array( 'class' => 'mw-infobox-right' ) ).
 716                                 $text.
 717                                 Html::closeElement( 'div' );
 718                 $s .= Html::element( 'div', array( 'style' => 'clear: left;' ), ' ' );
 719
 720                 $s .= Html::closeElement( 'div' );
 721
 722                 $s .= Html::element( 'div', array( 'style' => 'clear: left;' ), ' ' );
 723
 724                 return $s;
 725         }
 726 }