includes/Preprocessor_DOM.php

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