includes/parser/Preprocessor_DOM.php

   1 <?php
   2
   3 /**
   4  * @ingroup Parser
   5  */
   6 class Preprocessor_DOM implements Preprocessor {
   7         var $parser, $memoryLimit;
   8
   9         const CACHE_VERSION = 1;
  10
  11         function __construct( $parser ) {
  12                 $this->parser = $parser;
  13                 $mem = ini_get( 'memory_limit' );
  14                 $this->memoryLimit = false;
  15                 if ( strval( $mem ) !== '' && $mem != -1 ) {
  16                         if ( preg_match( '/^\d+$/', $mem ) ) {
  17                                 $this->memoryLimit = $mem;
  18                         } elseif ( preg_match( '/^(\d+)M$/i', $mem, $m ) ) {
  19                                 $this->memoryLimit = $m[1] * 1048576;
  20                         }
  21                 }
  22         }
  23
  24         function newFrame() {
  25                 return new PPFrame_DOM( $this );
  26         }
  27
  28         function newCustomFrame( $args ) {
  29                 return new PPCustomFrame_DOM( $this, $args );
  30         }
  31
  32         function memCheck() {
  33                 if ( $this->memoryLimit === false ) {
  34                         return;
  35                 }
  36                 $usage = memory_get_usage();
  37                 if ( $usage > $this->memoryLimit * 0.9 ) {
  38                         $limit = intval( $this->memoryLimit * 0.9 / 1048576 + 0.5 );
  39                         throw new MWException( "Preprocessor hit 90% memory limit ($limit MB)" );
  40                 }
  41                 return $usage <= $this->memoryLimit * 0.8;
  42         }
  43
  44         /**
  45          * Preprocess some wikitext and return the document tree.
  46          * This is the ghost of Parser::replace_variables().
  47          *
  48          * @param string $text The text to parse
  49          * @param integer flags Bitwise combination of:
  50          *          Parser::PTD_FOR_INCLUSION    Handle <noinclude>/<includeonly> as if the text is being
  51          *                                     included. Default is to assume a direct page view.
  52          *
  53          * The generated DOM tree must depend only on the input text and the flags.
  54          * The DOM tree must be the same in OT_HTML and OT_WIKI mode, to avoid a regression of bug 4899.
  55          *
  56          * Any flag added to the $flags parameter here, or any other parameter liable to cause a
  57          * change in the DOM tree for a given text, must be passed through the section identifier
  58          * in the section edit link and thus back to extractSections().
  59          *
  60          * The output of this function is currently only cached in process memory, but a persistent
  61          * cache may be implemented at a later date which takes further advantage of these strict
  62          * dependency requirements.
  63          *
  64          * @private
  65          */
  66         function preprocessToObj( $text, $flags = 0 ) {
  67                 wfProfileIn( __METHOD__ );
  68                 global $wgMemc, $wgPreprocessorCacheThreshold;
  69
  70                 $xml = false;
  71                 $cacheable = strlen( $text ) > $wgPreprocessorCacheThreshold;
  72                 if ( $cacheable ) {
  73                         wfProfileIn( __METHOD__.'-cacheable' );
  74
  75                         $cacheKey = wfMemcKey( 'preprocess-xml', md5($text), $flags );
  76                         $cacheValue = $wgMemc->get( $cacheKey );
  77                         if ( $cacheValue ) {
  78                                 $version = substr( $cacheValue, 0, 8 );
  79                                 if ( intval( $version ) == self::CACHE_VERSION ) {
  80                                         $xml = substr( $cacheValue, 8 );
  81                                         // From the cache
  82                                         wfDebugLog( "Preprocessor", "Loaded preprocessor XML from memcached (key $cacheKey)" );
  83                                 }
  84                         }
  85                 }
  86                 if ( $xml === false ) {
  87                         if ( $cacheable ) {
  88                                 wfProfileIn( __METHOD__.'-cache-miss' );
  89                                 $xml = $this->preprocessToXml( $text, $flags );
  90                                 $cacheValue = sprintf( "%08d", self::CACHE_VERSION ) . $xml;
  91                                 $wgMemc->set( $cacheKey, $cacheValue, 86400 );
  92                                 wfProfileOut( __METHOD__.'-cache-miss' );
  93                                 wfDebugLog( "Preprocessor", "Saved preprocessor XML to memcached (key $cacheKey)" );
  94                         } else {
  95                                 $xml = $this->preprocessToXml( $text, $flags );
  96                         }
  97
  98                 }
  99                 wfProfileIn( __METHOD__.'-loadXML' );
 100                 $dom = new DOMDocument;
 101                 wfSuppressWarnings();
 102                 $result = $dom->loadXML( $xml );
 103                 wfRestoreWarnings();
 104                 if ( !$result ) {
 105                         // Try running the XML through UtfNormal to get rid of invalid characters
 106                         $xml = UtfNormal::cleanUp( $xml );
 107                         $result = $dom->loadXML( $xml );
 108                         if ( !$result ) {
 109                                 throw new MWException( __METHOD__.' generated invalid XML' );
 110                         }
 111                 }
 112                 $obj = new PPNode_DOM( $dom->documentElement );
 113                 wfProfileOut( __METHOD__.'-loadXML' );
 114                 if ( $cacheable ) {
 115                         wfProfileOut( __METHOD__.'-cacheable' );
 116                 }
 117                 wfProfileOut( __METHOD__ );
 118                 return $obj;
 119         }
 120
 121         function preprocessToXml( $text, $flags = 0 ) {
 122                 wfProfileIn( __METHOD__ );
 123                 $rules = array(
 124                         '{' => array(
 125                                 'end' => '}',
 126                                 'names' => array(
 127                                         2 => 'template',
 128                                         3 => 'tplarg',
 129                                 ),
 130                                 'min' => 2,
 131                                 'max' => 3,
 132                         ),
 133                         '[' => array(
 134                                 'end' => ']',
 135                                 'names' => array( 2 => null ),
 136                                 'min' => 2,
 137                                 'max' => 2,
 138                         )
 139                 );
 140
 141                 $forInclusion = $flags & Parser::PTD_FOR_INCLUSION;
 142
 143                 $xmlishElements = $this->parser->getStripList();
 144                 $enableOnlyinclude = false;
 145                 if ( $forInclusion ) {
 146                         $ignoredTags = array( 'includeonly', '/includeonly' );
 147                         $ignoredElements = array( 'noinclude' );
 148                         $xmlishElements[] = 'noinclude';
 149                         if ( strpos( $text, '<onlyinclude>' ) !== false && strpos( $text, '</onlyinclude>' ) !== false ) {
 150                                 $enableOnlyinclude = true;
 151                         }
 152                 } else {
 153                         $ignoredTags = array( 'noinclude', '/noinclude', 'onlyinclude', '/onlyinclude' );
 154                         $ignoredElements = array( 'includeonly' );
 155                         $xmlishElements[] = 'includeonly';
 156                 }
 157                 $xmlishRegex = implode( '|', array_merge( $xmlishElements, $ignoredTags ) );
 158
 159                 // Use "A" modifier (anchored) instead of "^", because ^ doesn't work with an offset
 160                 $elementsRegex = "~($xmlishRegex)(?:\s|\/>|>)|(!--)~iA";
 161
 162                 $stack = new PPDStack;
 163
 164                 $searchBase = "[{<\n"; #}
 165                 $revText = strrev( $text ); // For fast reverse searches
 166
 167                 $i = 0;                     # Input pointer, starts out pointing to a pseudo-newline before the start
 168                 $accum =& $stack->getAccum();   # Current accumulator
 169                 $accum = '<root>';
 170                 $findEquals = false;            # True to find equals signs in arguments
 171                 $findPipe = false;              # True to take notice of pipe characters
 172                 $headingIndex = 1;
 173                 $inHeading = false;        # True if $i is inside a possible heading
 174                 $noMoreGT = false;         # True if there are no more greater-than (>) signs right of $i
 175                 $findOnlyinclude = $enableOnlyinclude; # True to ignore all input up to the next <onlyinclude>
 176                 $fakeLineStart = true;     # Do a line-start run without outputting an LF character
 177
 178                 while ( true ) {
 179                         //$this->memCheck();
 180
 181                         if ( $findOnlyinclude ) {
 182                                 // Ignore all input up to the next <onlyinclude>
 183                                 $startPos = strpos( $text, '<onlyinclude>', $i );
 184                                 if ( $startPos === false ) {
 185                                         // Ignored section runs to the end
 186                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i ) ) . '</ignore>';
 187                                         break;
 188                                 }
 189                                 $tagEndPos = $startPos + strlen( '<onlyinclude>' ); // past-the-end
 190                                 $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i, $tagEndPos - $i ) ) . '</ignore>';
 191                                 $i = $tagEndPos;
 192                                 $findOnlyinclude = false;
 193                         }
 194
 195                         if ( $fakeLineStart ) {
 196                                 $found = 'line-start';
 197                                 $curChar = '';
 198                         } else {
 199                                 # Find next opening brace, closing brace or pipe
 200                                 $search = $searchBase;
 201                                 if ( $stack->top === false ) {
 202                                         $currentClosing = '';
 203                                 } else {
 204                                         $currentClosing = $stack->top->close;
 205                                         $search .= $currentClosing;
 206                                 }
 207                                 if ( $findPipe ) {
 208                                         $search .= '|';
 209                                 }
 210                                 if ( $findEquals ) {
 211                                         // First equals will be for the template
 212                                         $search .= '=';
 213                                 }
 214                                 $rule = null;
 215                                 # Output literal section, advance input counter
 216                                 $literalLength = strcspn( $text, $search, $i );
 217                                 if ( $literalLength > 0 ) {
 218                                         $accum .= htmlspecialchars( substr( $text, $i, $literalLength ) );
 219                                         $i += $literalLength;
 220                                 }
 221                                 if ( $i >= strlen( $text ) ) {
 222                                         if ( $currentClosing == "\n" ) {
 223                                                 // Do a past-the-end run to finish off the heading
 224                                                 $curChar = '';
 225                                                 $found = 'line-end';
 226                                         } else {
 227                                                 # All done
 228                                                 break;
 229                                         }
 230                                 } else {
 231                                         $curChar = $text[$i];
 232                                         if ( $curChar == '|' ) {
 233                                                 $found = 'pipe';
 234                                         } elseif ( $curChar == '=' ) {
 235                                                 $found = 'equals';
 236                                         } elseif ( $curChar == '<' ) {
 237                                                 $found = 'angle';
 238                                         } elseif ( $curChar == "\n" ) {
 239                                                 if ( $inHeading ) {
 240                                                         $found = 'line-end';
 241                                                 } else {
 242                                                         $found = 'line-start';
 243                                                 }
 244                                         } elseif ( $curChar == $currentClosing ) {
 245                                                 $found = 'close';
 246                                         } elseif ( isset( $rules[$curChar] ) ) {
 247                                                 $found = 'open';
 248                                                 $rule = $rules[$curChar];
 249                                         } else {
 250                                                 # Some versions of PHP have a strcspn which stops on null characters
 251                                                 # Ignore and continue
 252                                                 ++$i;
 253                                                 continue;
 254                                         }
 255                                 }
 256                         }
 257
 258                         if ( $found == 'angle' ) {
 259                                 $matches = false;
 260                                 // Handle </onlyinclude>
 261                                 if ( $enableOnlyinclude && substr( $text, $i, strlen( '</onlyinclude>' ) ) == '</onlyinclude>' ) {
 262                                         $findOnlyinclude = true;
 263                                         continue;
 264                                 }
 265
 266                                 // Determine element name
 267                                 if ( !preg_match( $elementsRegex, $text, $matches, 0, $i + 1 ) ) {
 268                                         // Element name missing or not listed
 269                                         $accum .= '&lt;';
 270                                         ++$i;
 271                                         continue;
 272                                 }
 273                                 // Handle comments
 274                                 if ( isset( $matches[2] ) && $matches[2] == '!--' ) {
 275                                         // To avoid leaving blank lines, when a comment is both preceded
 276                                         // and followed by a newline (ignoring spaces), trim leading and
 277                                         // trailing spaces and one of the newlines.
 278
 279                                         // Find the end
 280                                         $endPos = strpos( $text, '-->', $i + 4 );
 281                                         if ( $endPos === false ) {
 282                                                 // Unclosed comment in input, runs to end
 283                                                 $inner = substr( $text, $i );
 284                                                 $accum .= '<comment>' . htmlspecialchars( $inner ) . '</comment>';
 285                                                 $i = strlen( $text );
 286                                         } else {
 287                                                 // Search backwards for leading whitespace
 288                                                 $wsStart = $i ? ( $i - strspn( $revText, ' ', strlen( $text ) - $i ) ) : 0;
 289                                                 // Search forwards for trailing whitespace
 290                                                 // $wsEnd will be the position of the last space
 291                                                 $wsEnd = $endPos + 2 + strspn( $text, ' ', $endPos + 3 );
 292                                                 // Eat the line if possible
 293                                                 // TODO: This could theoretically be done if $wsStart == 0, i.e. for comments at
 294                                                 // the overall start. That's not how Sanitizer::removeHTMLcomments() did it, but
 295                                                 // it's a possible beneficial b/c break.
 296                                                 if ( $wsStart > 0 && substr( $text, $wsStart - 1, 1 ) == "\n"
 297                                                         && substr( $text, $wsEnd + 1, 1 ) == "\n" )
 298                                                 {
 299                                                         $startPos = $wsStart;
 300                                                         $endPos = $wsEnd + 1;
 301                                                         // Remove leading whitespace from the end of the accumulator
 302                                                         // Sanity check first though
 303                                                         $wsLength = $i - $wsStart;
 304                                                         if ( $wsLength > 0 && substr( $accum, -$wsLength ) === str_repeat( ' ', $wsLength ) ) {
 305                                                                 $accum = substr( $accum, 0, -$wsLength );
 306                                                         }
 307                                                         // Do a line-start run next time to look for headings after the comment
 308                                                         $fakeLineStart = true;
 309                                                 } else {
 310                                                         // No line to eat, just take the comment itself
 311                                                         $startPos = $i;
 312                                                         $endPos += 2;
 313                                                 }
 314
 315                                                 if ( $stack->top ) {
 316                                                         $part = $stack->top->getCurrentPart();
 317                                                         if ( isset( $part->commentEnd ) && $part->commentEnd == $wsStart - 1 ) {
 318                                                                 // Comments abutting, no change in visual end
 319                                                                 $part->commentEnd = $wsEnd;
 320                                                         } else {
 321                                                                 $part->visualEnd = $wsStart;
 322                                                                 $part->commentEnd = $endPos;
 323                                                         }
 324                                                 }
 325                                                 $i = $endPos + 1;
 326                                                 $inner = substr( $text, $startPos, $endPos - $startPos + 1 );
 327                                                 $accum .= '<comment>' . htmlspecialchars( $inner ) . '</comment>';
 328                                         }
 329                                         continue;
 330                                 }
 331                                 $name = $matches[1];
 332                                 $lowerName = strtolower( $name );
 333                                 $attrStart = $i + strlen( $name ) + 1;
 334
 335                                 // Find end of tag
 336                                 $tagEndPos = $noMoreGT ? false : strpos( $text, '>', $attrStart );
 337                                 if ( $tagEndPos === false ) {
 338                                         // Infinite backtrack
 339                                         // Disable tag search to prevent worst-case O(N^2) performance
 340                                         $noMoreGT = true;
 341                                         $accum .= '&lt;';
 342                                         ++$i;
 343                                         continue;
 344                                 }
 345
 346                                 // Handle ignored tags
 347                                 if ( in_array( $lowerName, $ignoredTags ) ) {
 348                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i, $tagEndPos - $i + 1 ) ) . '</ignore>';
 349                                         $i = $tagEndPos + 1;
 350                                         continue;
 351                                 }
 352
 353                                 $tagStartPos = $i;
 354                                 if ( $text[$tagEndPos-1] == '/' ) {
 355                                         $attrEnd = $tagEndPos - 1;
 356                                         $inner = null;
 357                                         $i = $tagEndPos + 1;
 358                                         $close = '';
 359                                 } else {
 360                                         $attrEnd = $tagEndPos;
 361                                         // Find closing tag
 362                                         if ( preg_match( "/<\/" . preg_quote( $name, '/' ) . "\s*>/i",
 363                                                         $text, $matches, PREG_OFFSET_CAPTURE, $tagEndPos + 1 ) )
 364                                         {
 365                                                 $inner = substr( $text, $tagEndPos + 1, $matches[0][1] - $tagEndPos - 1 );
 366                                                 $i = $matches[0][1] + strlen( $matches[0][0] );
 367                                                 $close = '<close>' . htmlspecialchars( $matches[0][0] ) . '</close>';
 368                                         } else {
 369                                                 // No end tag -- let it run out to the end of the text.
 370                                                 $inner = substr( $text, $tagEndPos + 1 );
 371                                                 $i = strlen( $text );
 372                                                 $close = '';
 373                                         }
 374                                 }
 375                                 // <includeonly> and <noinclude> just become <ignore> tags
 376                                 if ( in_array( $lowerName, $ignoredElements ) ) {
 377                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $tagStartPos, $i - $tagStartPos ) )
 378                                                 . '</ignore>';
 379                                         continue;
 380                                 }
 381
 382                                 $accum .= '<ext>';
 383                                 if ( $attrEnd <= $attrStart ) {
 384                                         $attr = '';
 385                                 } else {
 386                                         $attr = substr( $text, $attrStart, $attrEnd - $attrStart );
 387                                 }
 388                                 $accum .= '<name>' . htmlspecialchars( $name ) . '</name>' .
 389                                         // Note that the attr element contains the whitespace between name and attribute,
 390                                         // this is necessary for precise reconstruction during pre-save transform.
 391                                         '<attr>' . htmlspecialchars( $attr ) . '</attr>';
 392                                 if ( $inner !== null ) {
 393                                         $accum .= '<inner>' . htmlspecialchars( $inner ) . '</inner>';
 394                                 }
 395                                 $accum .= $close . '</ext>';
 396                         }
 397
 398                         elseif ( $found == 'line-start' ) {
 399                                 // Is this the start of a heading?
 400                                 // Line break belongs before the heading element in any case
 401                                 if ( $fakeLineStart ) {
 402                                         $fakeLineStart = false;
 403                                 } else {
 404                                         $accum .= $curChar;
 405                                         $i++;
 406                                 }
 407
 408                                 $count = strspn( $text, '=', $i, 6 );
 409                                 if ( $count == 1 && $findEquals ) {
 410                                         // DWIM: This looks kind of like a name/value separator
 411                                         // Let's let the equals handler have it and break the potential heading
 412                                         // This is heuristic, but AFAICT the methods for completely correct disambiguation are very complex.
 413                                 } elseif ( $count > 0 ) {
 414                                         $piece = array(
 415                                                 'open' => "\n",
 416                                                 'close' => "\n",
 417                                                 'parts' => array( new PPDPart( str_repeat( '=', $count ) ) ),
 418                                                 'startPos' => $i,
 419                                                 'count' => $count );
 420                                         $stack->push( $piece );
 421                                         $accum =& $stack->getAccum();
 422                                         extract( $stack->getFlags() );
 423                                         $i += $count;
 424                                 }
 425                         }
 426
 427                         elseif ( $found == 'line-end' ) {
 428                                 $piece = $stack->top;
 429                                 // A heading must be open, otherwise \n wouldn't have been in the search list
 430                                 assert( $piece->open == "\n" );
 431                                 $part = $piece->getCurrentPart();
 432                                 // Search back through the input to see if it has a proper close
 433                                 // Do this using the reversed string since the other solutions (end anchor, etc.) are inefficient
 434                                 $wsLength = strspn( $revText, " \t", strlen( $text ) - $i );
 435                                 $searchStart = $i - $wsLength;
 436                                 if ( isset( $part->commentEnd ) && $searchStart - 1 == $part->commentEnd ) {
 437                                         // Comment found at line end
 438                                         // Search for equals signs before the comment
 439                                         $searchStart = $part->visualEnd;
 440                                         $searchStart -= strspn( $revText, " \t", strlen( $text ) - $searchStart );
 441                                 }
 442                                 $count = $piece->count;
 443                                 $equalsLength = strspn( $revText, '=', strlen( $text ) - $searchStart );
 444                                 if ( $equalsLength > 0 ) {
 445                                         if ( $i - $equalsLength == $piece->startPos ) {
 446                                                 // This is just a single string of equals signs on its own line
 447                                                 // Replicate the doHeadings behaviour /={count}(.+)={count}/
 448                                                 // First find out how many equals signs there really are (don't stop at 6)
 449                                                 $count = $equalsLength;
 450                                                 if ( $count < 3 ) {
 451                                                         $count = 0;
 452                                                 } else {
 453                                                         $count = min( 6, intval( ( $count - 1 ) / 2 ) );
 454                                                 }
 455                                         } else {
 456                                                 $count = min( $equalsLength, $count );
 457                                         }
 458                                         if ( $count > 0 ) {
 459                                                 // Normal match, output <h>
 460                                                 $element = "<h level=\"$count\" i=\"$headingIndex\">$accum</h>";
 461                                                 $headingIndex++;
 462                                         } else {
 463                                                 // Single equals sign on its own line, count=0
 464                                                 $element = $accum;
 465                                         }
 466                                 } else {
 467                                         // No match, no <h>, just pass down the inner text
 468                                         $element = $accum;
 469                                 }
 470                                 // Unwind the stack
 471                                 $stack->pop();
 472                                 $accum =& $stack->getAccum();
 473                                 extract( $stack->getFlags() );
 474
 475                                 // Append the result to the enclosing accumulator
 476                                 $accum .= $element;
 477                                 // Note that we do NOT increment the input pointer.
 478                                 // This is because the closing linebreak could be the opening linebreak of
 479                                 // another heading. Infinite loops are avoided because the next iteration MUST
 480                                 // hit the heading open case above, which unconditionally increments the
 481                                 // input pointer.
 482                         }
 483
 484                         elseif ( $found == 'open' ) {
 485                                 # count opening brace characters
 486                                 $count = strspn( $text, $curChar, $i );
 487
 488                                 # we need to add to stack only if opening brace count is enough for one of the rules
 489                                 if ( $count >= $rule['min'] ) {
 490                                         # Add it to the stack
 491                                         $piece = array(
 492                                                 'open' => $curChar,
 493                                                 'close' => $rule['end'],
 494                                                 'count' => $count,
 495                                                 'lineStart' => ($i > 0 && $text[$i-1] == "\n"),
 496                                         );
 497
 498                                         $stack->push( $piece );
 499                                         $accum =& $stack->getAccum();
 500                                         extract( $stack->getFlags() );
 501                                 } else {
 502                                         # Add literal brace(s)
 503                                         $accum .= htmlspecialchars( str_repeat( $curChar, $count ) );
 504                                 }
 505                                 $i += $count;
 506                         }
 507
 508                         elseif ( $found == 'close' ) {
 509                                 $piece = $stack->top;
 510                                 # lets check if there are enough characters for closing brace
 511                                 $maxCount = $piece->count;
 512                                 $count = strspn( $text, $curChar, $i, $maxCount );
 513
 514                                 # check for maximum matching characters (if there are 5 closing
 515                                 # characters, we will probably need only 3 - depending on the rules)
 516                                 $matchingCount = 0;
 517                                 $rule = $rules[$piece->open];
 518                                 if ( $count > $rule['max'] ) {
 519                                         # The specified maximum exists in the callback array, unless the caller
 520                                         # has made an error
 521                                         $matchingCount = $rule['max'];
 522                                 } else {
 523                                         # Count is less than the maximum
 524                                         # Skip any gaps in the callback array to find the true largest match
 525                                         # Need to use array_key_exists not isset because the callback can be null
 526                                         $matchingCount = $count;
 527                                         while ( $matchingCount > 0 && !array_key_exists( $matchingCount, $rule['names'] ) ) {
 528                                                 --$matchingCount;
 529                                         }
 530                                 }
 531
 532                                 if ($matchingCount <= 0) {
 533                                         # No matching element found in callback array
 534                                         # Output a literal closing brace and continue
 535                                         $accum .= htmlspecialchars( str_repeat( $curChar, $count ) );
 536                                         $i += $count;
 537                                         continue;
 538                                 }
 539                                 $name = $rule['names'][$matchingCount];
 540                                 if ( $name === null ) {
 541                                         // No element, just literal text
 542                                         $element = $piece->breakSyntax( $matchingCount ) . str_repeat( $rule['end'], $matchingCount );
 543                                 } else {
 544                                         # Create XML element
 545                                         # Note: $parts is already XML, does not need to be encoded further
 546                                         $parts = $piece->parts;
 547                                         $title = $parts[0]->out;
 548                                         unset( $parts[0] );
 549
 550                                         # The invocation is at the start of the line if lineStart is set in
 551                                         # the stack, and all opening brackets are used up.
 552                                         if ( $maxCount == $matchingCount && !empty( $piece->lineStart ) ) {
 553                                                 $attr = ' lineStart="1"';
 554                                         } else {
 555                                                 $attr = '';
 556                                         }
 557
 558                                         $element = "<$name$attr>";
 559                                         $element .= "<title>$title</title>";
 560                                         $argIndex = 1;
 561                                         foreach ( $parts as $partIndex => $part ) {
 562                                                 if ( isset( $part->eqpos ) ) {
 563                                                         $argName = substr( $part->out, 0, $part->eqpos );
 564                                                         $argValue = substr( $part->out, $part->eqpos + 1 );
 565                                                         $element .= "<part><name>$argName</name>=<value>$argValue</value></part>";
 566                                                 } else {
 567                                                         $element .= "<part><name index=\"$argIndex\" /><value>{$part->out}</value></part>";
 568                                                         $argIndex++;
 569                                                 }
 570                                         }
 571                                         $element .= "</$name>";
 572                                 }
 573
 574                                 # Advance input pointer
 575                                 $i += $matchingCount;
 576
 577                                 # Unwind the stack
 578                                 $stack->pop();
 579                                 $accum =& $stack->getAccum();
 580
 581                                 # Re-add the old stack element if it still has unmatched opening characters remaining
 582                                 if ($matchingCount < $piece->count) {
 583                                         $piece->parts = array( new PPDPart );
 584                                         $piece->count -= $matchingCount;
 585                                         # do we still qualify for any callback with remaining count?
 586                                         $names = $rules[$piece->open]['names'];
 587                                         $skippedBraces = 0;
 588                                         $enclosingAccum =& $accum;
 589                                         while ( $piece->count ) {
 590                                                 if ( array_key_exists( $piece->count, $names ) ) {
 591                                                         $stack->push( $piece );
 592                                                         $accum =& $stack->getAccum();
 593                                                         break;
 594                                                 }
 595                                                 --$piece->count;
 596                                                 $skippedBraces ++;
 597                                         }
 598                                         $enclosingAccum .= str_repeat( $piece->open, $skippedBraces );
 599                                 }
 600
 601                                 extract( $stack->getFlags() );
 602
 603                                 # Add XML element to the enclosing accumulator
 604                                 $accum .= $element;
 605                         }
 606
 607                         elseif ( $found == 'pipe' ) {
 608                                 $findEquals = true; // shortcut for getFlags()
 609                                 $stack->addPart();
 610                                 $accum =& $stack->getAccum();
 611                                 ++$i;
 612                         }
 613
 614                         elseif ( $found == 'equals' ) {
 615                                 $findEquals = false; // shortcut for getFlags()
 616                                 $stack->getCurrentPart()->eqpos = strlen( $accum );
 617                                 $accum .= '=';
 618                                 ++$i;
 619                         }
 620                 }
 621
 622                 # Output any remaining unclosed brackets
 623                 foreach ( $stack->stack as $piece ) {
 624                         $stack->rootAccum .= $piece->breakSyntax();
 625                 }
 626                 $stack->rootAccum .= '</root>';
 627                 $xml = $stack->rootAccum;
 628
 629                 wfProfileOut( __METHOD__ );
 630
 631                 return $xml;
 632         }
 633 }
 634
 635 /**
 636  * Stack class to help Preprocessor::preprocessToObj()
 637  * @ingroup Parser
 638  */
 639 class PPDStack {
 640         var $stack, $rootAccum, $top;
 641         var $out;
 642         var $elementClass = 'PPDStackElement';
 643
 644         static $false = false;
 645
 646         function __construct() {
 647                 $this->stack = array();
 648                 $this->top = false;
 649                 $this->rootAccum = '';
 650                 $this->accum =& $this->rootAccum;
 651         }
 652
 653         function count() {
 654                 return count( $this->stack );
 655         }
 656
 657         function &getAccum() {
 658                 return $this->accum;
 659         }
 660
 661         function getCurrentPart() {
 662                 if ( $this->top === false ) {
 663                         return false;
 664                 } else {
 665                         return $this->top->getCurrentPart();
 666                 }
 667         }
 668
 669         function push( $data ) {
 670                 if ( $data instanceof $this->elementClass ) {
 671                         $this->stack[] = $data;
 672                 } else {
 673                         $class = $this->elementClass;
 674                         $this->stack[] = new $class( $data );
 675                 }
 676                 $this->top = $this->stack[ count( $this->stack ) - 1 ];
 677                 $this->accum =& $this->top->getAccum();
 678         }
 679
 680         function pop() {
 681                 if ( !count( $this->stack ) ) {
 682                         throw new MWException( __METHOD__.': no elements remaining' );
 683                 }
 684                 $temp = array_pop( $this->stack );
 685
 686                 if ( count( $this->stack ) ) {
 687                         $this->top = $this->stack[ count( $this->stack ) - 1 ];
 688                         $this->accum =& $this->top->getAccum();
 689                 } else {
 690                         $this->top = self::$false;
 691                         $this->accum =& $this->rootAccum;
 692                 }
 693                 return $temp;
 694         }
 695
 696         function addPart( $s = '' ) {
 697                 $this->top->addPart( $s );
 698                 $this->accum =& $this->top->getAccum();
 699         }
 700
 701         function getFlags() {
 702                 if ( !count( $this->stack ) ) {
 703                         return array(
 704                                 'findEquals' => false,
 705                                 'findPipe' => false,
 706                                 'inHeading' => false,
 707                         );
 708                 } else {
 709                         return $this->top->getFlags();
 710                 }
 711         }
 712 }
 713
 714 /**
 715  * @ingroup Parser
 716  */
 717 class PPDStackElement {
 718         var $open,                      // Opening character (\n for heading)
 719                 $close,             // Matching closing character
 720                 $count,             // Number of opening characters found (number of "=" for heading)
 721                 $parts,             // Array of PPDPart objects describing pipe-separated parts.
 722                 $lineStart;         // True if the open char appeared at the start of the input line. Not set for headings.
 723
 724         var $partClass = 'PPDPart';
 725
 726         function __construct( $data = array() ) {
 727                 $class = $this->partClass;
 728                 $this->parts = array( new $class );
 729
 730                 foreach ( $data as $name => $value ) {
 731                         $this->$name = $value;
 732                 }
 733         }
 734
 735         function &getAccum() {
 736                 return $this->parts[count($this->parts) - 1]->out;
 737         }
 738
 739         function addPart( $s = '' ) {
 740                 $class = $this->partClass;
 741                 $this->parts[] = new $class( $s );
 742         }
 743
 744         function getCurrentPart() {
 745                 return $this->parts[count($this->parts) - 1];
 746         }
 747
 748         function getFlags() {
 749                 $partCount = count( $this->parts );
 750                 $findPipe = $this->open != "\n" && $this->open != '[';
 751                 return array(
 752                         'findPipe' => $findPipe,
 753                         'findEquals' => $findPipe && $partCount > 1 && !isset( $this->parts[$partCount - 1]->eqpos ),
 754                         'inHeading' => $this->open == "\n",
 755                 );
 756         }
 757
 758         /**
 759          * Get the output string that would result if the close is not found.
 760          */
 761         function breakSyntax( $openingCount = false ) {
 762                 if ( $this->open == "\n" ) {
 763                         $s = $this->parts[0]->out;
 764                 } else {
 765                         if ( $openingCount === false ) {
 766                                 $openingCount = $this->count;
 767                         }
 768                         $s = str_repeat( $this->open, $openingCount );
 769                         $first = true;
 770                         foreach ( $this->parts as $part ) {
 771                                 if ( $first ) {
 772                                         $first = false;
 773                                 } else {
 774                                         $s .= '|';
 775                                 }
 776                                 $s .= $part->out;
 777                         }
 778                 }
 779                 return $s;
 780         }
 781 }
 782
 783 /**
 784  * @ingroup Parser
 785  */
 786 class PPDPart {
 787         var $out; // Output accumulator string
 788
 789         // Optional member variables:
 790         //   eqpos        Position of equals sign in output accumulator
 791         //   commentEnd   Past-the-end input pointer for the last comment encountered
 792         //   visualEnd    Past-the-end input pointer for the end of the accumulator minus comments
 793
 794         function __construct( $out = '' ) {
 795                 $this->out = $out;
 796         }
 797 }
 798
 799 /**
 800  * An expansion frame, used as a context to expand the result of preprocessToObj()
 801  * @ingroup Parser
 802  */
 803 class PPFrame_DOM implements PPFrame {
 804         var $preprocessor, $parser, $title;
 805         var $titleCache;
 806
 807         /**
 808          * Hashtable listing templates which are disallowed for expansion in this frame,
 809          * having been encountered previously in parent frames.
 810          */
 811         var $loopCheckHash;
 812
 813         /**
 814          * Recursion depth of this frame, top = 0
 815          * Note that this is NOT the same as expansion depth in expand()
 816          */
 817         var $depth;
 818
 819
 820         /**
 821          * Construct a new preprocessor frame.
 822          * @param Preprocessor $preprocessor The parent preprocessor
 823          */
 824         function __construct( $preprocessor ) {
 825                 $this->preprocessor = $preprocessor;
 826                 $this->parser = $preprocessor->parser;
 827                 $this->title = $this->parser->mTitle;
 828                 $this->titleCache = array( $this->title ? $this->title->getPrefixedDBkey() : false );
 829                 $this->loopCheckHash = array();
 830                 $this->depth = 0;
 831         }
 832
 833         /**
 834          * Create a new child frame
 835          * $args is optionally a multi-root PPNode or array containing the template arguments
 836          */
 837         function newChild( $args = false, $title = false ) {
 838                 $namedArgs = array();
 839                 $numberedArgs = array();
 840                 if ( $title === false ) {
 841                         $title = $this->title;
 842                 }
 843                 if ( $args !== false ) {
 844                         $xpath = false;
 845                         if ( $args instanceof PPNode ) {
 846                                 $args = $args->node;
 847                         }
 848                         foreach ( $args as $arg ) {
 849                                 if ( !$xpath ) {
 850                                         $xpath = new DOMXPath( $arg->ownerDocument );
 851                                 }
 852
 853                                 $nameNodes = $xpath->query( 'name', $arg );
 854                                 $value = $xpath->query( 'value', $arg );
 855                                 if ( $nameNodes->item( 0 )->hasAttributes() ) {
 856                                         // Numbered parameter
 857                                         $index = $nameNodes->item( 0 )->attributes->getNamedItem( 'index' )->textContent;
 858                                         $numberedArgs[$index] = $value->item( 0 );
 859                                         unset( $namedArgs[$index] );
 860                                 } else {
 861                                         // Named parameter
 862                                         $name = trim( $this->expand( $nameNodes->item( 0 ), PPFrame::STRIP_COMMENTS ) );
 863                                         $namedArgs[$name] = $value->item( 0 );
 864                                         unset( $numberedArgs[$name] );
 865                                 }
 866                         }
 867                 }
 868                 return new PPTemplateFrame_DOM( $this->preprocessor, $this, $numberedArgs, $namedArgs, $title );
 869         }
 870
 871         function expand( $root, $flags = 0 ) {
 872                 static $expansionDepth = 0;
 873                 if ( is_string( $root ) ) {
 874                         return $root;
 875                 }
 876
 877                 if ( ++$this->parser->mPPNodeCount > $this->parser->mOptions->mMaxPPNodeCount )
 878                 {
 879                         return '<span class="error">Node-count limit exceeded</span>';
 880                 }
 881
 882                 if ( $expansionDepth > $this->parser->mOptions->mMaxPPExpandDepth ) {
 883                         return '<span class="error">Expansion depth limit exceeded</span>';
 884                 }
 885                 wfProfileIn( __METHOD__ );
 886                 ++$expansionDepth;
 887
 888                 if ( $root instanceof PPNode_DOM ) {
 889                         $root = $root->node;
 890                 }
 891                 if ( $root instanceof DOMDocument ) {
 892                         $root = $root->documentElement;
 893                 }
 894
 895                 $outStack = array( '', '' );
 896                 $iteratorStack = array( false, $root );
 897                 $indexStack = array( 0, 0 );
 898
 899                 while ( count( $iteratorStack ) > 1 ) {
 900                         $level = count( $outStack ) - 1;
 901                         $iteratorNode =& $iteratorStack[ $level ];
 902                         $out =& $outStack[$level];
 903                         $index =& $indexStack[$level];
 904
 905                         if ( $iteratorNode instanceof PPNode_DOM ) $iteratorNode = $iteratorNode->node;
 906
 907                         if ( is_array( $iteratorNode ) ) {
 908                                 if ( $index >= count( $iteratorNode ) ) {
 909                                         // All done with this iterator
 910                                         $iteratorStack[$level] = false;
 911                                         $contextNode = false;
 912                                 } else {
 913                                         $contextNode = $iteratorNode[$index];
 914                                         $index++;
 915                                 }
 916                         } elseif ( $iteratorNode instanceof DOMNodeList ) {
 917                                 if ( $index >= $iteratorNode->length ) {
 918                                         // All done with this iterator
 919                                         $iteratorStack[$level] = false;
 920                                         $contextNode = false;
 921                                 } else {
 922                                         $contextNode = $iteratorNode->item( $index );
 923                                         $index++;
 924                                 }
 925                         } else {
 926                                 // Copy to $contextNode and then delete from iterator stack,
 927                                 // because this is not an iterator but we do have to execute it once
 928                                 $contextNode = $iteratorStack[$level];
 929                                 $iteratorStack[$level] = false;
 930                         }
 931
 932                         if ( $contextNode instanceof PPNode_DOM ) $contextNode = $contextNode->node;
 933
 934                         $newIterator = false;
 935
 936                         if ( $contextNode === false ) {
 937                                 // nothing to do
 938                         } elseif ( is_string( $contextNode ) ) {
 939                                 $out .= $contextNode;
 940                         } elseif ( is_array( $contextNode ) || $contextNode instanceof DOMNodeList ) {
 941                                 $newIterator = $contextNode;
 942                         } elseif ( $contextNode instanceof DOMNode ) {
 943                                 if ( $contextNode->nodeType == XML_TEXT_NODE ) {
 944                                         $out .= $contextNode->nodeValue;
 945                                 } elseif ( $contextNode->nodeName == 'template' ) {
 946                                         # Double-brace expansion
 947                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
 948                                         $titles = $xpath->query( 'title', $contextNode );
 949                                         $title = $titles->item( 0 );
 950                                         $parts = $xpath->query( 'part', $contextNode );
 951                                         if ( $flags & self::NO_TEMPLATES ) {
 952                                                 $newIterator = $this->virtualBracketedImplode( '{{', '|', '}}', $title, $parts );
 953                                         } else {
 954                                                 $lineStart = $contextNode->getAttribute( 'lineStart' );
 955                                                 $params = array(
 956                                                         'title' => new PPNode_DOM( $title ),
 957                                                         'parts' => new PPNode_DOM( $parts ),
 958                                                         'lineStart' => $lineStart );
 959                                                 $ret = $this->parser->braceSubstitution( $params, $this );
 960                                                 if ( isset( $ret['object'] ) ) {
 961                                                         $newIterator = $ret['object'];
 962                                                 } else {
 963                                                         $out .= $ret['text'];
 964                                                 }
 965                                         }
 966                                 } elseif ( $contextNode->nodeName == 'tplarg' ) {
 967                                         # Triple-brace expansion
 968                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
 969                                         $titles = $xpath->query( 'title', $contextNode );
 970                                         $title = $titles->item( 0 );
 971                                         $parts = $xpath->query( 'part', $contextNode );
 972                                         if ( $flags & self::NO_ARGS ) {
 973                                                 $newIterator = $this->virtualBracketedImplode( '{{{', '|', '}}}', $title, $parts );
 974                                         } else {
 975                                                 $params = array(
 976                                                         'title' => new PPNode_DOM( $title ),
 977                                                         'parts' => new PPNode_DOM( $parts ) );
 978                                                 $ret = $this->parser->argSubstitution( $params, $this );
 979                                                 if ( isset( $ret['object'] ) ) {
 980                                                         $newIterator = $ret['object'];
 981                                                 } else {
 982                                                         $out .= $ret['text'];
 983                                                 }
 984                                         }
 985                                 } elseif ( $contextNode->nodeName == 'comment' ) {
 986                                         # HTML-style comment
 987                                         # Remove it in HTML, pre+remove and STRIP_COMMENTS modes
 988                                         if ( $this->parser->ot['html']
 989                                                 || ( $this->parser->ot['pre'] && $this->parser->mOptions->getRemoveComments() )
 990                                                 || ( $flags & self::STRIP_COMMENTS ) )
 991                                         {
 992                                                 $out .= '';
 993                                         }
 994                                         # Add a strip marker in PST mode so that pstPass2() can run some old-fashioned regexes on the result
 995                                         # Not in RECOVER_COMMENTS mode (extractSections) though
 996                                         elseif ( $this->parser->ot['wiki'] && ! ( $flags & self::RECOVER_COMMENTS ) ) {
 997                                                 $out .= $this->parser->insertStripItem( $contextNode->textContent );
 998                                         }
 999                                         # Recover the literal comment in RECOVER_COMMENTS and pre+no-remove
1000                                         else {
1001                                                 $out .= $contextNode->textContent;
1002                                         }
1003                                 } elseif ( $contextNode->nodeName == 'ignore' ) {
1004                                         # Output suppression used by <includeonly> etc.
1005                                         # OT_WIKI will only respect <ignore> in substed templates.
1006                                         # The other output types respect it unless NO_IGNORE is set.
1007                                         # extractSections() sets NO_IGNORE and so never respects it.
1008                                         if ( ( !isset( $this->parent ) && $this->parser->ot['wiki'] ) || ( $flags & self::NO_IGNORE ) ) {
1009                                                 $out .= $contextNode->textContent;
1010                                         } else {
1011                                                 $out .= '';
1012                                         }
1013                                 } elseif ( $contextNode->nodeName == 'ext' ) {
1014                                         # Extension tag
1015                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
1016                                         $names = $xpath->query( 'name', $contextNode );
1017                                         $attrs = $xpath->query( 'attr', $contextNode );
1018                                         $inners = $xpath->query( 'inner', $contextNode );
1019                                         $closes = $xpath->query( 'close', $contextNode );
1020                                         $params = array(
1021                                                 'name' => new PPNode_DOM( $names->item( 0 ) ),
1022                                                 'attr' => $attrs->length > 0 ? new PPNode_DOM( $attrs->item( 0 ) ) : null,
1023                                                 'inner' => $inners->length > 0 ? new PPNode_DOM( $inners->item( 0 ) ) : null,
1024                                                 'close' => $closes->length > 0 ? new PPNode_DOM( $closes->item( 0 ) ) : null,
1025                                         );
1026                                         $out .= $this->parser->extensionSubstitution( $params, $this );
1027                                 } elseif ( $contextNode->nodeName == 'h' ) {
1028                                         # Heading
1029                                         $s = $this->expand( $contextNode->childNodes, $flags );
1030
1031                     # Insert a heading marker only for <h> children of <root>
1032                     # This is to stop extractSections from going over multiple tree levels
1033                     if ( $contextNode->parentNode->nodeName == 'root'
1034                       && $this->parser->ot['html'] )
1035                     {
1036                                                 # Insert heading index marker
1037                                                 $headingIndex = $contextNode->getAttribute( 'i' );
1038                                                 $titleText = $this->title->getPrefixedDBkey();
1039                                                 $this->parser->mHeadings[] = array( $titleText, $headingIndex );
1040                                                 $serial = count( $this->parser->mHeadings ) - 1;
1041                                                 $marker = "{$this->parser->mUniqPrefix}-h-$serial-" . Parser::MARKER_SUFFIX;
1042                                                 $count = $contextNode->getAttribute( 'level' );
1043                                                 $s = substr( $s, 0, $count ) . $marker . substr( $s, $count );
1044                                                 $this->parser->mStripState->general->setPair( $marker, '' );
1045                                         }
1046                                         $out .= $s;
1047                                 } else {
1048                                         # Generic recursive expansion
1049                                         $newIterator = $contextNode->childNodes;
1050                                 }
1051                         } else {
1052                                 wfProfileOut( __METHOD__ );
1053                                 throw new MWException( __METHOD__.': Invalid parameter type' );
1054                         }
1055
1056                         if ( $newIterator !== false ) {
1057                                 if ( $newIterator instanceof PPNode_DOM ) {
1058                                         $newIterator = $newIterator->node;
1059                                 }
1060                                 $outStack[] = '';
1061                                 $iteratorStack[] = $newIterator;
1062                                 $indexStack[] = 0;
1063                         } elseif ( $iteratorStack[$level] === false ) {
1064                                 // Return accumulated value to parent
1065                                 // With tail recursion
1066                                 while ( $iteratorStack[$level] === false && $level > 0 ) {
1067                                         $outStack[$level - 1] .= $out;
1068                                         array_pop( $outStack );
1069                                         array_pop( $iteratorStack );
1070                                         array_pop( $indexStack );
1071                                         $level--;
1072                                 }
1073                         }
1074                 }
1075                 --$expansionDepth;
1076                 wfProfileOut( __METHOD__ );
1077                 return $outStack[0];
1078         }
1079
1080         function implodeWithFlags( $sep, $flags /*, ... */ ) {
1081                 $args = array_slice( func_get_args(), 2 );
1082
1083                 $first = true;
1084                 $s = '';
1085                 foreach ( $args as $root ) {
1086                         if ( $root instanceof PPNode_DOM ) $root = $root->node;
1087                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1088                                 $root = array( $root );
1089                         }
1090                         foreach ( $root as $node ) {
1091                                 if ( $first ) {
1092                                         $first = false;
1093                                 } else {
1094                                         $s .= $sep;
1095                                 }
1096                                 $s .= $this->expand( $node, $flags );
1097                         }
1098                 }
1099                 return $s;
1100         }
1101
1102         /**
1103          * Implode with no flags specified
1104          * This previously called implodeWithFlags but has now been inlined to reduce stack depth
1105          */
1106         function implode( $sep /*, ... */ ) {
1107                 $args = array_slice( func_get_args(), 1 );
1108
1109                 $first = true;
1110                 $s = '';
1111                 foreach ( $args as $root ) {
1112                         if ( $root instanceof PPNode_DOM ) $root = $root->node;
1113                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1114                                 $root = array( $root );
1115                         }
1116                         foreach ( $root as $node ) {
1117                                 if ( $first ) {
1118                                         $first = false;
1119                                 } else {
1120                                         $s .= $sep;
1121                                 }
1122                                 $s .= $this->expand( $node );
1123                         }
1124                 }
1125                 return $s;
1126         }
1127
1128         /**
1129          * Makes an object that, when expand()ed, will be the same as one obtained
1130          * with implode()
1131          */
1132         function virtualImplode( $sep /*, ... */ ) {
1133                 $args = array_slice( func_get_args(), 1 );
1134                 $out = array();
1135                 $first = true;
1136                 if ( $root instanceof PPNode_DOM ) $root = $root->node;
1137
1138                 foreach ( $args as $root ) {
1139                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1140                                 $root = array( $root );
1141                         }
1142                         foreach ( $root as $node ) {
1143                                 if ( $first ) {
1144                                         $first = false;
1145                                 } else {
1146                                         $out[] = $sep;
1147                                 }
1148                                 $out[] = $node;
1149                         }
1150                 }
1151                 return $out;
1152         }
1153
1154         /**
1155          * Virtual implode with brackets
1156          */
1157         function virtualBracketedImplode( $start, $sep, $end /*, ... */ ) {
1158                 $args = array_slice( func_get_args(), 3 );
1159                 $out = array( $start );
1160                 $first = true;
1161
1162                 foreach ( $args as $root ) {
1163                         if ( $root instanceof PPNode_DOM ) $root = $root->node;
1164                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1165                                 $root = array( $root );
1166                         }
1167                         foreach ( $root as $node ) {
1168                                 if ( $first ) {
1169                                         $first = false;
1170                                 } else {
1171                                         $out[] = $sep;
1172                                 }
1173                                 $out[] = $node;
1174                         }
1175                 }
1176                 $out[] = $end;
1177                 return $out;
1178         }
1179
1180         function __toString() {
1181                 return 'frame{}';
1182         }
1183
1184         function getPDBK( $level = false ) {
1185                 if ( $level === false ) {
1186                         return $this->title->getPrefixedDBkey();
1187                 } else {
1188                         return isset( $this->titleCache[$level] ) ? $this->titleCache[$level] : false;
1189                 }
1190         }
1191
1192         /**
1193          * Returns true if there are no arguments in this frame
1194          */
1195         function isEmpty() {
1196                 return true;
1197         }
1198
1199         function getArgument( $name ) {
1200                 return false;
1201         }
1202
1203         /**
1204          * Returns true if the infinite loop check is OK, false if a loop is detected
1205          */
1206         function loopCheck( $title ) {
1207                 return !isset( $this->loopCheckHash[$title->getPrefixedDBkey()] );
1208         }
1209
1210         /**
1211          * Return true if the frame is a template frame
1212          */
1213         function isTemplate() {
1214                 return false;
1215         }
1216 }
1217
1218 /**
1219  * Expansion frame with template arguments
1220  * @ingroup Parser
1221  */
1222 class PPTemplateFrame_DOM extends PPFrame_DOM {
1223         var $numberedArgs, $namedArgs, $parent;
1224         var $numberedExpansionCache, $namedExpansionCache;
1225
1226         function __construct( $preprocessor, $parent = false, $numberedArgs = array(), $namedArgs = array(), $title = false ) {
1227                 $this->preprocessor = $preprocessor;
1228                 $this->parser = $preprocessor->parser;
1229                 $this->parent = $parent;
1230                 $this->numberedArgs = $numberedArgs;
1231                 $this->namedArgs = $namedArgs;
1232                 $this->title = $title;
1233                 $pdbk = $title ? $title->getPrefixedDBkey() : false;
1234                 $this->titleCache = $parent->titleCache;
1235                 $this->titleCache[] = $pdbk;
1236                 $this->loopCheckHash = /*clone*/ $parent->loopCheckHash;
1237                 if ( $pdbk !== false ) {
1238                         $this->loopCheckHash[$pdbk] = true;
1239                 }
1240                 $this->depth = $parent->depth + 1;
1241                 $this->numberedExpansionCache = $this->namedExpansionCache = array();
1242         }
1243
1244         function __toString() {
1245                 $s = 'tplframe{';
1246                 $first = true;
1247                 $args = $this->numberedArgs + $this->namedArgs;
1248                 foreach ( $args as $name => $value ) {
1249                         if ( $first ) {
1250                                 $first = false;
1251                         } else {
1252                                 $s .= ', ';
1253                         }
1254                         $s .= "\"$name\":\"" .
1255                                 str_replace( '"', '\\"', $value->ownerDocument->saveXML( $value ) ) . '"';
1256                 }
1257                 $s .= '}';
1258                 return $s;
1259         }
1260         /**
1261          * Returns true if there are no arguments in this frame
1262          */
1263         function isEmpty() {
1264                 return !count( $this->numberedArgs ) && !count( $this->namedArgs );
1265         }
1266
1267         function getArguments() {
1268                 $arguments = array();
1269                 foreach ( array_merge(
1270                                 array_keys($this->numberedArgs),
1271                                 array_keys($this->namedArgs)) as $key ) {
1272                         $arguments[$key] = $this->getArgument($key);
1273                 }
1274                 return $arguments;
1275         }
1276
1277         function getNumberedArguments() {
1278                 $arguments = array();
1279                 foreach ( array_keys($this->numberedArgs) as $key ) {
1280                         $arguments[$key] = $this->getArgument($key);
1281                 }
1282                 return $arguments;
1283         }
1284
1285         function getNamedArguments() {
1286                 $arguments = array();
1287                 foreach ( array_keys($this->namedArgs) as $key ) {
1288                         $arguments[$key] = $this->getArgument($key);
1289                 }
1290                 return $arguments;
1291         }
1292
1293         function getNumberedArgument( $index ) {
1294                 if ( !isset( $this->numberedArgs[$index] ) ) {
1295                         return false;
1296                 }
1297                 if ( !isset( $this->numberedExpansionCache[$index] ) ) {
1298                         # No trimming for unnamed arguments
1299                         $this->numberedExpansionCache[$index] = $this->parent->expand( $this->numberedArgs[$index], self::STRIP_COMMENTS );
1300                 }
1301                 return $this->numberedExpansionCache[$index];
1302         }
1303
1304         function getNamedArgument( $name ) {
1305                 if ( !isset( $this->namedArgs[$name] ) ) {
1306                         return false;
1307                 }
1308                 if ( !isset( $this->namedExpansionCache[$name] ) ) {
1309                         # Trim named arguments post-expand, for backwards compatibility
1310                         $this->namedExpansionCache[$name] = trim(
1311                                 $this->parent->expand( $this->namedArgs[$name], self::STRIP_COMMENTS ) );
1312                 }
1313                 return $this->namedExpansionCache[$name];
1314         }
1315
1316         function getArgument( $name ) {
1317                 $text = $this->getNumberedArgument( $name );
1318                 if ( $text === false ) {
1319                         $text = $this->getNamedArgument( $name );
1320                 }
1321                 return $text;
1322         }
1323
1324         /**
1325          * Return true if the frame is a template frame
1326          */
1327         function isTemplate() {
1328                 return true;
1329         }
1330 }
1331
1332 /**
1333  * Expansion frame with custom arguments
1334  * @ingroup Parser
1335  */
1336 class PPCustomFrame_DOM extends PPFrame_DOM {
1337         var $args;
1338
1339         function __construct( $preprocessor, $args ) {
1340                 $this->preprocessor = $preprocessor;
1341                 $this->parser = $preprocessor->parser;
1342                 $this->args = $args;
1343         }
1344
1345         function __toString() {
1346                 $s = 'cstmframe{';
1347                 $first = true;
1348                 foreach ( $this->args as $name => $value ) {
1349                         if ( $first ) {
1350                                 $first = false;
1351                         } else {
1352                                 $s .= ', ';
1353                         }
1354                         $s .= "\"$name\":\"" .
1355                                 str_replace( '"', '\\"', $value->__toString() ) . '"';
1356                 }
1357                 $s .= '}';
1358                 return $s;
1359         }
1360
1361         function isEmpty() {
1362                 return !count( $this->args );
1363         }
1364
1365         function getArgument( $index ) {
1366                 if ( !isset( $this->args[$index] ) ) {
1367                         return false;
1368                 }
1369                 return $this->args[$index];
1370         }
1371 }
1372
1373 /**
1374  * @ingroup Parser
1375  */
1376 class PPNode_DOM implements PPNode {
1377         var $node;
1378
1379         function __construct( $node, $xpath = false ) {
1380                 $this->node = $node;
1381         }
1382
1383         function __get( $name ) {
1384                 if ( $name == 'xpath' ) {
1385                         $this->xpath = new DOMXPath( $this->node->ownerDocument );
1386                 }
1387                 return $this->xpath;
1388         }
1389
1390         function __toString() {
1391                 if ( $this->node instanceof DOMNodeList ) {
1392                         $s = '';
1393                         foreach ( $this->node as $node ) {
1394                                 $s .= $node->ownerDocument->saveXML( $node );
1395                         }
1396                 } else {
1397                         $s = $this->node->ownerDocument->saveXML( $this->node );
1398                 }
1399                 return $s;
1400         }
1401
1402         function getChildren() {
1403                 return $this->node->childNodes ? new self( $this->node->childNodes ) : false;
1404         }
1405
1406         function getFirstChild() {
1407                 return $this->node->firstChild ? new self( $this->node->firstChild ) : false;
1408         }
1409
1410         function getNextSibling() {
1411                 return $this->node->nextSibling ? new self( $this->node->nextSibling ) : false;
1412         }
1413
1414         function getChildrenOfType( $type ) {
1415                 return new self( $this->xpath->query( $type, $this->node ) );
1416         }
1417
1418         function getLength() {
1419                 if ( $this->node instanceof DOMNodeList ) {
1420                         return $this->node->length;
1421                 } else {
1422                         return false;
1423                 }
1424         }
1425
1426         function item( $i ) {
1427                 $item = $this->node->item( $i );
1428                 return $item ? new self( $item ) : false;
1429         }
1430
1431         function getName() {
1432                 if ( $this->node instanceof DOMNodeList ) {
1433                         return '#nodelist';
1434                 } else {
1435                         return $this->node->nodeName;
1436                 }
1437         }
1438
1439         /**
1440          * Split a <part> node into an associative array containing:
1441          *    name          PPNode name
1442          *    index         String index
1443          *    value         PPNode value
1444          */
1445         function splitArg() {
1446                 $names = $this->xpath->query( 'name', $this->node );
1447                 $values = $this->xpath->query( 'value', $this->node );
1448                 if ( !$names->length || !$values->length ) {
1449                         throw new MWException( 'Invalid brace node passed to ' . __METHOD__ );
1450                 }
1451                 $name = $names->item( 0 );
1452                 $index = $name->getAttribute( 'index' );
1453                 return array(
1454                         'name' => new self( $name ),
1455                         'index' => $index,
1456                         'value' => new self( $values->item( 0 ) ) );
1457         }
1458
1459         /**
1460          * Split an <ext> node into an associative array containing name, attr, inner and close
1461          * All values in the resulting array are PPNodes. Inner and close are optional.
1462          */
1463         function splitExt() {
1464                 $names = $this->xpath->query( 'name', $this->node );
1465                 $attrs = $this->xpath->query( 'attr', $this->node );
1466                 $inners = $this->xpath->query( 'inner', $this->node );
1467                 $closes = $this->xpath->query( 'close', $this->node );
1468                 if ( !$names->length || !$attrs->length ) {
1469                         throw new MWException( 'Invalid ext node passed to ' . __METHOD__ );
1470                 }
1471                 $parts = array(
1472                         'name' => new self( $names->item( 0 ) ),
1473                         'attr' => new self( $attrs->item( 0 ) ) );
1474                 if ( $inners->length ) {
1475                         $parts['inner'] = new self( $inners->item( 0 ) );
1476                 }
1477                 if ( $closes->length ) {
1478                         $parts['close'] = new self( $closes->item( 0 ) );
1479                 }
1480                 return $parts;
1481         }
1482
1483         /**
1484          * Split a <h> node
1485          */
1486         function splitHeading() {
1487                 if ( !$this->nodeName == 'h' ) {
1488                         throw new MWException( 'Invalid h node passed to ' . __METHOD__ );
1489                 }
1490                 return array(
1491                         'i' => $this->node->getAttribute( 'i' ),
1492                         'level' => $this->node->getAttribute( 'level' ),
1493                         'contents' => $this->getChildren()
1494                 );
1495         }
1496 }