includes/parser/Preprocessor_DOM.php

   1 <?php
   2 /**
   3  * Preprocessor using PHP's dom extension
   4  *
   5  * @file
   6  * @ingroup Parser
   7  */
   8
   9 /**
  10  * @ingroup Parser
  11  */
  12 class Preprocessor_DOM implements Preprocessor {
  13         var $parser, $memoryLimit;
  14
  15         const CACHE_VERSION = 1;
  16
  17         function __construct( $parser ) {
  18                 $this->parser = $parser;
  19                 $mem = ini_get( 'memory_limit' );
  20                 $this->memoryLimit = false;
  21                 if ( strval( $mem ) !== '' && $mem != -1 ) {
  22                         if ( preg_match( '/^\d+$/', $mem ) ) {
  23                                 $this->memoryLimit = $mem;
  24                         } elseif ( preg_match( '/^(\d+)M$/i', $mem, $m ) ) {
  25                                 $this->memoryLimit = $m[1] * 1048576;
  26                         }
  27                 }
  28         }
  29
  30         function newFrame() {
  31                 return new PPFrame_DOM( $this );
  32         }
  33
  34         function newCustomFrame( $args ) {
  35                 return new PPCustomFrame_DOM( $this, $args );
  36         }
  37
  38         function newPartNodeArray( $values ) {
  39                 //NOTE: DOM manipulation is slower than building & parsing XML! (or so Tim sais)
  40                 $xml = "<list>";
  41
  42                 foreach ( $values as $k => $val ) {
  43
  44                         if ( is_int( $k ) ) {
  45                                 $xml .= "<part><name index=\"$k\"/><value>" . htmlspecialchars( $val ) ."</value></part>";
  46                         } else {
  47                                 $xml .= "<part><name>" . htmlspecialchars( $k ) . "</name>=<value>" . htmlspecialchars( $val ) . "</value></part>";
  48                         }
  49                 }
  50
  51                 $xml .= "</list>";
  52
  53                 $dom = new DOMDocument();
  54                 $dom->loadXML( $xml );
  55                 $root = $dom->documentElement;
  56
  57                 $node = new PPNode_DOM( $root->childNodes );
  58                 return $node;
  59         }
  60
  61         function memCheck() {
  62                 if ( $this->memoryLimit === false ) {
  63                         return;
  64                 }
  65                 $usage = memory_get_usage();
  66                 if ( $usage > $this->memoryLimit * 0.9 ) {
  67                         $limit = intval( $this->memoryLimit * 0.9 / 1048576 + 0.5 );
  68                         throw new MWException( "Preprocessor hit 90% memory limit ($limit MB)" );
  69                 }
  70                 return $usage <= $this->memoryLimit * 0.8;
  71         }
  72
  73         /**
  74          * Preprocess some wikitext and return the document tree.
  75          * This is the ghost of Parser::replace_variables().
  76          *
  77          * @param $text String: the text to parse
  78          * @param $flags Integer: bitwise combination of:
  79          *          Parser::PTD_FOR_INCLUSION    Handle <noinclude>/<includeonly> as if the text is being
  80          *                                     included. Default is to assume a direct page view.
  81          *
  82          * The generated DOM tree must depend only on the input text and the flags.
  83          * The DOM tree must be the same in OT_HTML and OT_WIKI mode, to avoid a regression of bug 4899.
  84          *
  85          * Any flag added to the $flags parameter here, or any other parameter liable to cause a
  86          * change in the DOM tree for a given text, must be passed through the section identifier
  87          * in the section edit link and thus back to extractSections().
  88          *
  89          * The output of this function is currently only cached in process memory, but a persistent
  90          * cache may be implemented at a later date which takes further advantage of these strict
  91          * dependency requirements.
  92          *
  93          * @private
  94          */
  95         function preprocessToObj( $text, $flags = 0 ) {
  96                 wfProfileIn( __METHOD__ );
  97                 global $wgMemc, $wgPreprocessorCacheThreshold;
  98
  99                 $xml = false;
 100                 $cacheable = $wgPreprocessorCacheThreshold !== false && strlen( $text ) > $wgPreprocessorCacheThreshold;
 101                 if ( $cacheable ) {
 102                         wfProfileIn( __METHOD__.'-cacheable' );
 103
 104                         $cacheKey = wfMemcKey( 'preprocess-xml', md5($text), $flags );
 105                         $cacheValue = $wgMemc->get( $cacheKey );
 106                         if ( $cacheValue ) {
 107                                 $version = substr( $cacheValue, 0, 8 );
 108                                 if ( intval( $version ) == self::CACHE_VERSION ) {
 109                                         $xml = substr( $cacheValue, 8 );
 110                                         // From the cache
 111                                         wfDebugLog( "Preprocessor", "Loaded preprocessor XML from memcached (key $cacheKey)" );
 112                                 }
 113                         }
 114                 }
 115                 if ( $xml === false ) {
 116                         if ( $cacheable ) {
 117                                 wfProfileIn( __METHOD__.'-cache-miss' );
 118                                 $xml = $this->preprocessToXml( $text, $flags );
 119                                 $cacheValue = sprintf( "%08d", self::CACHE_VERSION ) . $xml;
 120                                 $wgMemc->set( $cacheKey, $cacheValue, 86400 );
 121                                 wfProfileOut( __METHOD__.'-cache-miss' );
 122                                 wfDebugLog( "Preprocessor", "Saved preprocessor XML to memcached (key $cacheKey)" );
 123                         } else {
 124                                 $xml = $this->preprocessToXml( $text, $flags );
 125                         }
 126
 127                 }
 128                 wfProfileIn( __METHOD__.'-loadXML' );
 129                 $dom = new DOMDocument;
 130                 wfSuppressWarnings();
 131                 $result = $dom->loadXML( $xml );
 132                 wfRestoreWarnings();
 133                 if ( !$result ) {
 134                         // Try running the XML through UtfNormal to get rid of invalid characters
 135                         $xml = UtfNormal::cleanUp( $xml );
 136                         $result = $dom->loadXML( $xml );
 137                         if ( !$result ) {
 138                                 throw new MWException( __METHOD__.' generated invalid XML' );
 139                         }
 140                 }
 141                 $obj = new PPNode_DOM( $dom->documentElement );
 142                 wfProfileOut( __METHOD__.'-loadXML' );
 143                 if ( $cacheable ) {
 144                         wfProfileOut( __METHOD__.'-cacheable' );
 145                 }
 146                 wfProfileOut( __METHOD__ );
 147                 return $obj;
 148         }
 149
 150         function preprocessToXml( $text, $flags = 0 ) {
 151                 wfProfileIn( __METHOD__ );
 152                 $rules = array(
 153                         '{' => array(
 154                                 'end' => '}',
 155                                 'names' => array(
 156                                         2 => 'template',
 157                                         3 => 'tplarg',
 158                                 ),
 159                                 'min' => 2,
 160                                 'max' => 3,
 161                         ),
 162                         '[' => array(
 163                                 'end' => ']',
 164                                 'names' => array( 2 => null ),
 165                                 'min' => 2,
 166                                 'max' => 2,
 167                         )
 168                 );
 169
 170                 $forInclusion = $flags & Parser::PTD_FOR_INCLUSION;
 171
 172                 $xmlishElements = $this->parser->getStripList();
 173                 $enableOnlyinclude = false;
 174                 if ( $forInclusion ) {
 175                         $ignoredTags = array( 'includeonly', '/includeonly' );
 176                         $ignoredElements = array( 'noinclude' );
 177                         $xmlishElements[] = 'noinclude';
 178                         if ( strpos( $text, '<onlyinclude>' ) !== false && strpos( $text, '</onlyinclude>' ) !== false ) {
 179                                 $enableOnlyinclude = true;
 180                         }
 181                 } else {
 182                         $ignoredTags = array( 'noinclude', '/noinclude', 'onlyinclude', '/onlyinclude' );
 183                         $ignoredElements = array( 'includeonly' );
 184                         $xmlishElements[] = 'includeonly';
 185                 }
 186                 $xmlishRegex = implode( '|', array_merge( $xmlishElements, $ignoredTags ) );
 187
 188                 // Use "A" modifier (anchored) instead of "^", because ^ doesn't work with an offset
 189                 $elementsRegex = "~($xmlishRegex)(?:\s|\/>|>)|(!--)~iA";
 190
 191                 $stack = new PPDStack;
 192
 193                 $searchBase = "[{<\n"; #}
 194                 $revText = strrev( $text ); // For fast reverse searches
 195
 196                 $i = 0;                     # Input pointer, starts out pointing to a pseudo-newline before the start
 197                 $accum =& $stack->getAccum();   # Current accumulator
 198                 $accum = '<root>';
 199                 $findEquals = false;            # True to find equals signs in arguments
 200                 $findPipe = false;              # True to take notice of pipe characters
 201                 $headingIndex = 1;
 202                 $inHeading = false;        # True if $i is inside a possible heading
 203                 $noMoreGT = false;         # True if there are no more greater-than (>) signs right of $i
 204                 $findOnlyinclude = $enableOnlyinclude; # True to ignore all input up to the next <onlyinclude>
 205                 $fakeLineStart = true;     # Do a line-start run without outputting an LF character
 206
 207                 while ( true ) {
 208                         //$this->memCheck();
 209
 210                         if ( $findOnlyinclude ) {
 211                                 // Ignore all input up to the next <onlyinclude>
 212                                 $startPos = strpos( $text, '<onlyinclude>', $i );
 213                                 if ( $startPos === false ) {
 214                                         // Ignored section runs to the end
 215                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i ) ) . '</ignore>';
 216                                         break;
 217                                 }
 218                                 $tagEndPos = $startPos + strlen( '<onlyinclude>' ); // past-the-end
 219                                 $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i, $tagEndPos - $i ) ) . '</ignore>';
 220                                 $i = $tagEndPos;
 221                                 $findOnlyinclude = false;
 222                         }
 223
 224                         if ( $fakeLineStart ) {
 225                                 $found = 'line-start';
 226                                 $curChar = '';
 227                         } else {
 228                                 # Find next opening brace, closing brace or pipe
 229                                 $search = $searchBase;
 230                                 if ( $stack->top === false ) {
 231                                         $currentClosing = '';
 232                                 } else {
 233                                         $currentClosing = $stack->top->close;
 234                                         $search .= $currentClosing;
 235                                 }
 236                                 if ( $findPipe ) {
 237                                         $search .= '|';
 238                                 }
 239                                 if ( $findEquals ) {
 240                                         // First equals will be for the template
 241                                         $search .= '=';
 242                                 }
 243                                 $rule = null;
 244                                 # Output literal section, advance input counter
 245                                 $literalLength = strcspn( $text, $search, $i );
 246                                 if ( $literalLength > 0 ) {
 247                                         $accum .= htmlspecialchars( substr( $text, $i, $literalLength ) );
 248                                         $i += $literalLength;
 249                                 }
 250                                 if ( $i >= strlen( $text ) ) {
 251                                         if ( $currentClosing == "\n" ) {
 252                                                 // Do a past-the-end run to finish off the heading
 253                                                 $curChar = '';
 254                                                 $found = 'line-end';
 255                                         } else {
 256                                                 # All done
 257                                                 break;
 258                                         }
 259                                 } else {
 260                                         $curChar = $text[$i];
 261                                         if ( $curChar == '|' ) {
 262                                                 $found = 'pipe';
 263                                         } elseif ( $curChar == '=' ) {
 264                                                 $found = 'equals';
 265                                         } elseif ( $curChar == '<' ) {
 266                                                 $found = 'angle';
 267                                         } elseif ( $curChar == "\n" ) {
 268                                                 if ( $inHeading ) {
 269                                                         $found = 'line-end';
 270                                                 } else {
 271                                                         $found = 'line-start';
 272                                                 }
 273                                         } elseif ( $curChar == $currentClosing ) {
 274                                                 $found = 'close';
 275                                         } elseif ( isset( $rules[$curChar] ) ) {
 276                                                 $found = 'open';
 277                                                 $rule = $rules[$curChar];
 278                                         } else {
 279                                                 # Some versions of PHP have a strcspn which stops on null characters
 280                                                 # Ignore and continue
 281                                                 ++$i;
 282                                                 continue;
 283                                         }
 284                                 }
 285                         }
 286
 287                         if ( $found == 'angle' ) {
 288                                 $matches = false;
 289                                 // Handle </onlyinclude>
 290                                 if ( $enableOnlyinclude && substr( $text, $i, strlen( '</onlyinclude>' ) ) == '</onlyinclude>' ) {
 291                                         $findOnlyinclude = true;
 292                                         continue;
 293                                 }
 294
 295                                 // Determine element name
 296                                 if ( !preg_match( $elementsRegex, $text, $matches, 0, $i + 1 ) ) {
 297                                         // Element name missing or not listed
 298                                         $accum .= '&lt;';
 299                                         ++$i;
 300                                         continue;
 301                                 }
 302                                 // Handle comments
 303                                 if ( isset( $matches[2] ) && $matches[2] == '!--' ) {
 304                                         // To avoid leaving blank lines, when a comment is both preceded
 305                                         // and followed by a newline (ignoring spaces), trim leading and
 306                                         // trailing spaces and one of the newlines.
 307
 308                                         // Find the end
 309                                         $endPos = strpos( $text, '-->', $i + 4 );
 310                                         if ( $endPos === false ) {
 311                                                 // Unclosed comment in input, runs to end
 312                                                 $inner = substr( $text, $i );
 313                                                 $accum .= '<comment>' . htmlspecialchars( $inner ) . '</comment>';
 314                                                 $i = strlen( $text );
 315                                         } else {
 316                                                 // Search backwards for leading whitespace
 317                                                 $wsStart = $i ? ( $i - strspn( $revText, ' ', strlen( $text ) - $i ) ) : 0;
 318                                                 // Search forwards for trailing whitespace
 319                                                 // $wsEnd will be the position of the last space (or the '>' if there's none)
 320                                                 $wsEnd = $endPos + 2 + strspn( $text, ' ', $endPos + 3 );
 321                                                 // Eat the line if possible
 322                                                 // TODO: This could theoretically be done if $wsStart == 0, i.e. for comments at
 323                                                 // the overall start. That's not how Sanitizer::removeHTMLcomments() did it, but
 324                                                 // it's a possible beneficial b/c break.
 325                                                 if ( $wsStart > 0 && substr( $text, $wsStart - 1, 1 ) == "\n"
 326                                                         && substr( $text, $wsEnd + 1, 1 ) == "\n" )
 327                                                 {
 328                                                         $startPos = $wsStart;
 329                                                         $endPos = $wsEnd + 1;
 330                                                         // Remove leading whitespace from the end of the accumulator
 331                                                         // Sanity check first though
 332                                                         $wsLength = $i - $wsStart;
 333                                                         if ( $wsLength > 0 && substr( $accum, -$wsLength ) === str_repeat( ' ', $wsLength ) ) {
 334                                                                 $accum = substr( $accum, 0, -$wsLength );
 335                                                         }
 336                                                         // Do a line-start run next time to look for headings after the comment
 337                                                         $fakeLineStart = true;
 338                                                 } else {
 339                                                         // No line to eat, just take the comment itself
 340                                                         $startPos = $i;
 341                                                         $endPos += 2;
 342                                                 }
 343
 344                                                 if ( $stack->top ) {
 345                                                         $part = $stack->top->getCurrentPart();
 346                                                         if ( ! (isset( $part->commentEnd ) && $part->commentEnd == $wsStart - 1 )) {
 347                                                                 $part->visualEnd = $wsStart;
 348                                                         }
 349                                                         // Else comments abutting, no change in visual end
 350                                                         $part->commentEnd = $endPos;
 351                                                 }
 352                                                 $i = $endPos + 1;
 353                                                 $inner = substr( $text, $startPos, $endPos - $startPos + 1 );
 354                                                 $accum .= '<comment>' . htmlspecialchars( $inner ) . '</comment>';
 355                                         }
 356                                         continue;
 357                                 }
 358                                 $name = $matches[1];
 359                                 $lowerName = strtolower( $name );
 360                                 $attrStart = $i + strlen( $name ) + 1;
 361
 362                                 // Find end of tag
 363                                 $tagEndPos = $noMoreGT ? false : strpos( $text, '>', $attrStart );
 364                                 if ( $tagEndPos === false ) {
 365                                         // Infinite backtrack
 366                                         // Disable tag search to prevent worst-case O(N^2) performance
 367                                         $noMoreGT = true;
 368                                         $accum .= '&lt;';
 369                                         ++$i;
 370                                         continue;
 371                                 }
 372
 373                                 // Handle ignored tags
 374                                 if ( in_array( $lowerName, $ignoredTags ) ) {
 375                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i, $tagEndPos - $i + 1 ) ) . '</ignore>';
 376                                         $i = $tagEndPos + 1;
 377                                         continue;
 378                                 }
 379
 380                                 $tagStartPos = $i;
 381                                 if ( $text[$tagEndPos-1] == '/' ) {
 382                                         $attrEnd = $tagEndPos - 1;
 383                                         $inner = null;
 384                                         $i = $tagEndPos + 1;
 385                                         $close = '';
 386                                 } else {
 387                                         $attrEnd = $tagEndPos;
 388                                         // Find closing tag
 389                                         if ( preg_match( "/<\/" . preg_quote( $name, '/' ) . "\s*>/i",
 390                                                         $text, $matches, PREG_OFFSET_CAPTURE, $tagEndPos + 1 ) )
 391                                         {
 392                                                 $inner = substr( $text, $tagEndPos + 1, $matches[0][1] - $tagEndPos - 1 );
 393                                                 $i = $matches[0][1] + strlen( $matches[0][0] );
 394                                                 $close = '<close>' . htmlspecialchars( $matches[0][0] ) . '</close>';
 395                                         } else {
 396                                                 // No end tag -- let it run out to the end of the text.
 397                                                 $inner = substr( $text, $tagEndPos + 1 );
 398                                                 $i = strlen( $text );
 399                                                 $close = '';
 400                                         }
 401                                 }
 402                                 // <includeonly> and <noinclude> just become <ignore> tags
 403                                 if ( in_array( $lowerName, $ignoredElements ) ) {
 404                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $tagStartPos, $i - $tagStartPos ) )
 405                                                 . '</ignore>';
 406                                         continue;
 407                                 }
 408
 409                                 $accum .= '<ext>';
 410                                 if ( $attrEnd <= $attrStart ) {
 411                                         $attr = '';
 412                                 } else {
 413                                         $attr = substr( $text, $attrStart, $attrEnd - $attrStart );
 414                                 }
 415                                 $accum .= '<name>' . htmlspecialchars( $name ) . '</name>' .
 416                                         // Note that the attr element contains the whitespace between name and attribute,
 417                                         // this is necessary for precise reconstruction during pre-save transform.
 418                                         '<attr>' . htmlspecialchars( $attr ) . '</attr>';
 419                                 if ( $inner !== null ) {
 420                                         $accum .= '<inner>' . htmlspecialchars( $inner ) . '</inner>';
 421                                 }
 422                                 $accum .= $close . '</ext>';
 423                         }
 424
 425                         elseif ( $found == 'line-start' ) {
 426                                 // Is this the start of a heading?
 427                                 // Line break belongs before the heading element in any case
 428                                 if ( $fakeLineStart ) {
 429                                         $fakeLineStart = false;
 430                                 } else {
 431                                         $accum .= $curChar;
 432                                         $i++;
 433                                 }
 434
 435                                 $count = strspn( $text, '=', $i, 6 );
 436                                 if ( $count == 1 && $findEquals ) {
 437                                         // DWIM: This looks kind of like a name/value separator
 438                                         // Let's let the equals handler have it and break the potential heading
 439                                         // This is heuristic, but AFAICT the methods for completely correct disambiguation are very complex.
 440                                 } elseif ( $count > 0 ) {
 441                                         $piece = array(
 442                                                 'open' => "\n",
 443                                                 'close' => "\n",
 444                                                 'parts' => array( new PPDPart( str_repeat( '=', $count ) ) ),
 445                                                 'startPos' => $i,
 446                                                 'count' => $count );
 447                                         $stack->push( $piece );
 448                                         $accum =& $stack->getAccum();
 449                                         $flags = $stack->getFlags();
 450                                         extract( $flags );
 451                                         $i += $count;
 452                                 }
 453                         }
 454
 455                         elseif ( $found == 'line-end' ) {
 456                                 $piece = $stack->top;
 457                                 // A heading must be open, otherwise \n wouldn't have been in the search list
 458                                 assert( $piece->open == "\n" );
 459                                 $part = $piece->getCurrentPart();
 460                                 // Search back through the input to see if it has a proper close
 461                                 // Do this using the reversed string since the other solutions (end anchor, etc.) are inefficient
 462                                 $wsLength = strspn( $revText, " \t", strlen( $text ) - $i );
 463                                 $searchStart = $i - $wsLength;
 464                                 if ( isset( $part->commentEnd ) && $searchStart - 1 == $part->commentEnd ) {
 465                                         // Comment found at line end
 466                                         // Search for equals signs before the comment
 467                                         $searchStart = $part->visualEnd;
 468                                         $searchStart -= strspn( $revText, " \t", strlen( $text ) - $searchStart );
 469                                 }
 470                                 $count = $piece->count;
 471                                 $equalsLength = strspn( $revText, '=', strlen( $text ) - $searchStart );
 472                                 if ( $equalsLength > 0 ) {
 473                                         if ( $searchStart - $equalsLength == $piece->startPos ) {
 474                                                 // This is just a single string of equals signs on its own line
 475                                                 // Replicate the doHeadings behaviour /={count}(.+)={count}/
 476                                                 // First find out how many equals signs there really are (don't stop at 6)
 477                                                 $count = $equalsLength;
 478                                                 if ( $count < 3 ) {
 479                                                         $count = 0;
 480                                                 } else {
 481                                                         $count = min( 6, intval( ( $count - 1 ) / 2 ) );
 482                                                 }
 483                                         } else {
 484                                                 $count = min( $equalsLength, $count );
 485                                         }
 486                                         if ( $count > 0 ) {
 487                                                 // Normal match, output <h>
 488                                                 $element = "<h level=\"$count\" i=\"$headingIndex\">$accum</h>";
 489                                                 $headingIndex++;
 490                                         } else {
 491                                                 // Single equals sign on its own line, count=0
 492                                                 $element = $accum;
 493                                         }
 494                                 } else {
 495                                         // No match, no <h>, just pass down the inner text
 496                                         $element = $accum;
 497                                 }
 498                                 // Unwind the stack
 499                                 $stack->pop();
 500                                 $accum =& $stack->getAccum();
 501                                 $flags = $stack->getFlags();
 502                                 extract( $flags );
 503
 504                                 // Append the result to the enclosing accumulator
 505                                 $accum .= $element;
 506                                 // Note that we do NOT increment the input pointer.
 507                                 // This is because the closing linebreak could be the opening linebreak of
 508                                 // another heading. Infinite loops are avoided because the next iteration MUST
 509                                 // hit the heading open case above, which unconditionally increments the
 510                                 // input pointer.
 511                         } elseif ( $found == 'open' ) {
 512                                 # count opening brace characters
 513                                 $count = strspn( $text, $curChar, $i );
 514
 515                                 # we need to add to stack only if opening brace count is enough for one of the rules
 516                                 if ( $count >= $rule['min'] ) {
 517                                         # Add it to the stack
 518                                         $piece = array(
 519                                                 'open' => $curChar,
 520                                                 'close' => $rule['end'],
 521                                                 'count' => $count,
 522                                                 'lineStart' => ($i == 0 || $text[$i-1] == "\n"),
 523                                         );
 524
 525                                         $stack->push( $piece );
 526                                         $accum =& $stack->getAccum();
 527                                         $flags = $stack->getFlags();
 528                                         extract( $flags );
 529                                 } else {
 530                                         # Add literal brace(s)
 531                                         $accum .= htmlspecialchars( str_repeat( $curChar, $count ) );
 532                                 }
 533                                 $i += $count;
 534                         } elseif ( $found == 'close' ) {
 535                                 $piece = $stack->top;
 536                                 # lets check if there are enough characters for closing brace
 537                                 $maxCount = $piece->count;
 538                                 $count = strspn( $text, $curChar, $i, $maxCount );
 539
 540                                 # check for maximum matching characters (if there are 5 closing
 541                                 # characters, we will probably need only 3 - depending on the rules)
 542                                 $rule = $rules[$piece->open];
 543                                 if ( $count > $rule['max'] ) {
 544                                         # The specified maximum exists in the callback array, unless the caller
 545                                         # has made an error
 546                                         $matchingCount = $rule['max'];
 547                                 } else {
 548                                         # Count is less than the maximum
 549                                         # Skip any gaps in the callback array to find the true largest match
 550                                         # Need to use array_key_exists not isset because the callback can be null
 551                                         $matchingCount = $count;
 552                                         while ( $matchingCount > 0 && !array_key_exists( $matchingCount, $rule['names'] ) ) {
 553                                                 --$matchingCount;
 554                                         }
 555                                 }
 556
 557                                 if ($matchingCount <= 0) {
 558                                         # No matching element found in callback array
 559                                         # Output a literal closing brace and continue
 560                                         $accum .= htmlspecialchars( str_repeat( $curChar, $count ) );
 561                                         $i += $count;
 562                                         continue;
 563                                 }
 564                                 $name = $rule['names'][$matchingCount];
 565                                 if ( $name === null ) {
 566                                         // No element, just literal text
 567                                         $element = $piece->breakSyntax( $matchingCount ) . str_repeat( $rule['end'], $matchingCount );
 568                                 } else {
 569                                         # Create XML element
 570                                         # Note: $parts is already XML, does not need to be encoded further
 571                                         $parts = $piece->parts;
 572                                         $title = $parts[0]->out;
 573                                         unset( $parts[0] );
 574
 575                                         # The invocation is at the start of the line if lineStart is set in
 576                                         # the stack, and all opening brackets are used up.
 577                                         if ( $maxCount == $matchingCount && !empty( $piece->lineStart ) ) {
 578                                                 $attr = ' lineStart="1"';
 579                                         } else {
 580                                                 $attr = '';
 581                                         }
 582
 583                                         $element = "<$name$attr>";
 584                                         $element .= "<title>$title</title>";
 585                                         $argIndex = 1;
 586                                         foreach ( $parts as $part ) {
 587                                                 if ( isset( $part->eqpos ) ) {
 588                                                         $argName = substr( $part->out, 0, $part->eqpos );
 589                                                         $argValue = substr( $part->out, $part->eqpos + 1 );
 590                                                         $element .= "<part><name>$argName</name>=<value>$argValue</value></part>";
 591                                                 } else {
 592                                                         $element .= "<part><name index=\"$argIndex\" /><value>{$part->out}</value></part>";
 593                                                         $argIndex++;
 594                                                 }
 595                                         }
 596                                         $element .= "</$name>";
 597                                 }
 598
 599                                 # Advance input pointer
 600                                 $i += $matchingCount;
 601
 602                                 # Unwind the stack
 603                                 $stack->pop();
 604                                 $accum =& $stack->getAccum();
 605
 606                                 # Re-add the old stack element if it still has unmatched opening characters remaining
 607                                 if ($matchingCount < $piece->count) {
 608                                         $piece->parts = array( new PPDPart );
 609                                         $piece->count -= $matchingCount;
 610                                         # do we still qualify for any callback with remaining count?
 611                                         $names = $rules[$piece->open]['names'];
 612                                         $skippedBraces = 0;
 613                                         $enclosingAccum =& $accum;
 614                                         while ( $piece->count ) {
 615                                                 if ( array_key_exists( $piece->count, $names ) ) {
 616                                                         $stack->push( $piece );
 617                                                         $accum =& $stack->getAccum();
 618                                                         break;
 619                                                 }
 620                                                 --$piece->count;
 621                                                 $skippedBraces ++;
 622                                         }
 623                                         $enclosingAccum .= str_repeat( $piece->open, $skippedBraces );
 624                                 }
 625                                 $flags = $stack->getFlags();
 626                                 extract( $flags );
 627
 628                                 # Add XML element to the enclosing accumulator
 629                                 $accum .= $element;
 630                         }
 631
 632                         elseif ( $found == 'pipe' ) {
 633                                 $findEquals = true; // shortcut for getFlags()
 634                                 $stack->addPart();
 635                                 $accum =& $stack->getAccum();
 636                                 ++$i;
 637                         }
 638
 639                         elseif ( $found == 'equals' ) {
 640                                 $findEquals = false; // shortcut for getFlags()
 641                                 $stack->getCurrentPart()->eqpos = strlen( $accum );
 642                                 $accum .= '=';
 643                                 ++$i;
 644                         }
 645                 }
 646
 647                 # Output any remaining unclosed brackets
 648                 foreach ( $stack->stack as $piece ) {
 649                         $stack->rootAccum .= $piece->breakSyntax();
 650                 }
 651                 $stack->rootAccum .= '</root>';
 652                 $xml = $stack->rootAccum;
 653
 654                 wfProfileOut( __METHOD__ );
 655
 656                 return $xml;
 657         }
 658 }
 659
 660 /**
 661  * Stack class to help Preprocessor::preprocessToObj()
 662  * @ingroup Parser
 663  */
 664 class PPDStack {
 665         var $stack, $rootAccum, $top;
 666         var $out;
 667         var $elementClass = 'PPDStackElement';
 668
 669         static $false = false;
 670
 671         function __construct() {
 672                 $this->stack = array();
 673                 $this->top = false;
 674                 $this->rootAccum = '';
 675                 $this->accum =& $this->rootAccum;
 676         }
 677
 678         function count() {
 679                 return count( $this->stack );
 680         }
 681
 682         function &getAccum() {
 683                 return $this->accum;
 684         }
 685
 686         function getCurrentPart() {
 687                 if ( $this->top === false ) {
 688                         return false;
 689                 } else {
 690                         return $this->top->getCurrentPart();
 691                 }
 692         }
 693
 694         function push( $data ) {
 695                 if ( $data instanceof $this->elementClass ) {
 696                         $this->stack[] = $data;
 697                 } else {
 698                         $class = $this->elementClass;
 699                         $this->stack[] = new $class( $data );
 700                 }
 701                 $this->top = $this->stack[ count( $this->stack ) - 1 ];
 702                 $this->accum =& $this->top->getAccum();
 703         }
 704
 705         function pop() {
 706                 if ( !count( $this->stack ) ) {
 707                         throw new MWException( __METHOD__.': no elements remaining' );
 708                 }
 709                 $temp = array_pop( $this->stack );
 710
 711                 if ( count( $this->stack ) ) {
 712                         $this->top = $this->stack[ count( $this->stack ) - 1 ];
 713                         $this->accum =& $this->top->getAccum();
 714                 } else {
 715                         $this->top = self::$false;
 716                         $this->accum =& $this->rootAccum;
 717                 }
 718                 return $temp;
 719         }
 720
 721         function addPart( $s = '' ) {
 722                 $this->top->addPart( $s );
 723                 $this->accum =& $this->top->getAccum();
 724         }
 725
 726         function getFlags() {
 727                 if ( !count( $this->stack ) ) {
 728                         return array(
 729                                 'findEquals' => false,
 730                                 'findPipe' => false,
 731                                 'inHeading' => false,
 732                         );
 733                 } else {
 734                         return $this->top->getFlags();
 735                 }
 736         }
 737 }
 738
 739 /**
 740  * @ingroup Parser
 741  */
 742 class PPDStackElement {
 743         var $open,                      // Opening character (\n for heading)
 744                 $close,             // Matching closing character
 745                 $count,             // Number of opening characters found (number of "=" for heading)
 746                 $parts,             // Array of PPDPart objects describing pipe-separated parts.
 747                 $lineStart;         // True if the open char appeared at the start of the input line. Not set for headings.
 748
 749         var $partClass = 'PPDPart';
 750
 751         function __construct( $data = array() ) {
 752                 $class = $this->partClass;
 753                 $this->parts = array( new $class );
 754
 755                 foreach ( $data as $name => $value ) {
 756                         $this->$name = $value;
 757                 }
 758         }
 759
 760         function &getAccum() {
 761                 return $this->parts[count($this->parts) - 1]->out;
 762         }
 763
 764         function addPart( $s = '' ) {
 765                 $class = $this->partClass;
 766                 $this->parts[] = new $class( $s );
 767         }
 768
 769         function getCurrentPart() {
 770                 return $this->parts[count($this->parts) - 1];
 771         }
 772
 773         function getFlags() {
 774                 $partCount = count( $this->parts );
 775                 $findPipe = $this->open != "\n" && $this->open != '[';
 776                 return array(
 777                         'findPipe' => $findPipe,
 778                         'findEquals' => $findPipe && $partCount > 1 && !isset( $this->parts[$partCount - 1]->eqpos ),
 779                         'inHeading' => $this->open == "\n",
 780                 );
 781         }
 782
 783         /**
 784          * Get the output string that would result if the close is not found.
 785          */
 786         function breakSyntax( $openingCount = false ) {
 787                 if ( $this->open == "\n" ) {
 788                         $s = $this->parts[0]->out;
 789                 } else {
 790                         if ( $openingCount === false ) {
 791                                 $openingCount = $this->count;
 792                         }
 793                         $s = str_repeat( $this->open, $openingCount );
 794                         $first = true;
 795                         foreach ( $this->parts as $part ) {
 796                                 if ( $first ) {
 797                                         $first = false;
 798                                 } else {
 799                                         $s .= '|';
 800                                 }
 801                                 $s .= $part->out;
 802                         }
 803                 }
 804                 return $s;
 805         }
 806 }
 807
 808 /**
 809  * @ingroup Parser
 810  */
 811 class PPDPart {
 812         var $out; // Output accumulator string
 813
 814         // Optional member variables:
 815         //   eqpos        Position of equals sign in output accumulator
 816         //   commentEnd   Past-the-end input pointer for the last comment encountered
 817         //   visualEnd    Past-the-end input pointer for the end of the accumulator minus comments
 818
 819         function __construct( $out = '' ) {
 820                 $this->out = $out;
 821         }
 822 }
 823
 824 /**
 825  * An expansion frame, used as a context to expand the result of preprocessToObj()
 826  * @ingroup Parser
 827  */
 828 class PPFrame_DOM implements PPFrame {
 829         var $preprocessor, $parser, $title;
 830         var $titleCache;
 831
 832         /**
 833          * Hashtable listing templates which are disallowed for expansion in this frame,
 834          * having been encountered previously in parent frames.
 835          */
 836         var $loopCheckHash;
 837
 838         /**
 839          * Recursion depth of this frame, top = 0
 840          * Note that this is NOT the same as expansion depth in expand()
 841          */
 842         var $depth;
 843
 844
 845         /**
 846          * Construct a new preprocessor frame.
 847          * @param $preprocessor Preprocessor: The parent preprocessor
 848          */
 849         function __construct( $preprocessor ) {
 850                 $this->preprocessor = $preprocessor;
 851                 $this->parser = $preprocessor->parser;
 852                 $this->title = $this->parser->mTitle;
 853                 $this->titleCache = array( $this->title ? $this->title->getPrefixedDBkey() : false );
 854                 $this->loopCheckHash = array();
 855                 $this->depth = 0;
 856         }
 857
 858         /**
 859          * Create a new child frame
 860          * $args is optionally a multi-root PPNode or array containing the template arguments
 861          */
 862         function newChild( $args = false, $title = false ) {
 863                 $namedArgs = array();
 864                 $numberedArgs = array();
 865                 if ( $title === false ) {
 866                         $title = $this->title;
 867                 }
 868                 if ( $args !== false ) {
 869                         $xpath = false;
 870                         if ( $args instanceof PPNode ) {
 871                                 $args = $args->node;
 872                         }
 873                         foreach ( $args as $arg ) {
 874                                 if ( !$xpath ) {
 875                                         $xpath = new DOMXPath( $arg->ownerDocument );
 876                                 }
 877
 878                                 $nameNodes = $xpath->query( 'name', $arg );
 879                                 $value = $xpath->query( 'value', $arg );
 880                                 if ( $nameNodes->item( 0 )->hasAttributes() ) {
 881                                         // Numbered parameter
 882                                         $index = $nameNodes->item( 0 )->attributes->getNamedItem( 'index' )->textContent;
 883                                         $numberedArgs[$index] = $value->item( 0 );
 884                                         unset( $namedArgs[$index] );
 885                                 } else {
 886                                         // Named parameter
 887                                         $name = trim( $this->expand( $nameNodes->item( 0 ), PPFrame::STRIP_COMMENTS ) );
 888                                         $namedArgs[$name] = $value->item( 0 );
 889                                         unset( $numberedArgs[$name] );
 890                                 }
 891                         }
 892                 }
 893                 return new PPTemplateFrame_DOM( $this->preprocessor, $this, $numberedArgs, $namedArgs, $title );
 894         }
 895
 896         function expand( $root, $flags = 0 ) {
 897                 static $expansionDepth = 0;
 898                 if ( is_string( $root ) ) {
 899                         return $root;
 900                 }
 901
 902                 if ( ++$this->parser->mPPNodeCount > $this->parser->mOptions->getMaxPPNodeCount() )
 903                 {
 904                         return '<span class="error">Node-count limit exceeded</span>';
 905                 }
 906
 907                 if ( $expansionDepth > $this->parser->mOptions->getMaxPPExpandDepth() ) {
 908                         return '<span class="error">Expansion depth limit exceeded</span>';
 909                 }
 910                 wfProfileIn( __METHOD__ );
 911                 ++$expansionDepth;
 912
 913                 if ( $root instanceof PPNode_DOM ) {
 914                         $root = $root->node;
 915                 }
 916                 if ( $root instanceof DOMDocument ) {
 917                         $root = $root->documentElement;
 918                 }
 919
 920                 $outStack = array( '', '' );
 921                 $iteratorStack = array( false, $root );
 922                 $indexStack = array( 0, 0 );
 923
 924                 while ( count( $iteratorStack ) > 1 ) {
 925                         $level = count( $outStack ) - 1;
 926                         $iteratorNode =& $iteratorStack[ $level ];
 927                         $out =& $outStack[$level];
 928                         $index =& $indexStack[$level];
 929
 930                         if ( $iteratorNode instanceof PPNode_DOM ) $iteratorNode = $iteratorNode->node;
 931
 932                         if ( is_array( $iteratorNode ) ) {
 933                                 if ( $index >= count( $iteratorNode ) ) {
 934                                         // All done with this iterator
 935                                         $iteratorStack[$level] = false;
 936                                         $contextNode = false;
 937                                 } else {
 938                                         $contextNode = $iteratorNode[$index];
 939                                         $index++;
 940                                 }
 941                         } elseif ( $iteratorNode instanceof DOMNodeList ) {
 942                                 if ( $index >= $iteratorNode->length ) {
 943                                         // All done with this iterator
 944                                         $iteratorStack[$level] = false;
 945                                         $contextNode = false;
 946                                 } else {
 947                                         $contextNode = $iteratorNode->item( $index );
 948                                         $index++;
 949                                 }
 950                         } else {
 951                                 // Copy to $contextNode and then delete from iterator stack,
 952                                 // because this is not an iterator but we do have to execute it once
 953                                 $contextNode = $iteratorStack[$level];
 954                                 $iteratorStack[$level] = false;
 955                         }
 956
 957                         if ( $contextNode instanceof PPNode_DOM ) {
 958                                 $contextNode = $contextNode->node;
 959                         }
 960
 961                         $newIterator = false;
 962
 963                         if ( $contextNode === false ) {
 964                                 // nothing to do
 965                         } elseif ( is_string( $contextNode ) ) {
 966                                 $out .= $contextNode;
 967                         } elseif ( is_array( $contextNode ) || $contextNode instanceof DOMNodeList ) {
 968                                 $newIterator = $contextNode;
 969                         } elseif ( $contextNode instanceof DOMNode ) {
 970                                 if ( $contextNode->nodeType == XML_TEXT_NODE ) {
 971                                         $out .= $contextNode->nodeValue;
 972                                 } elseif ( $contextNode->nodeName == 'template' ) {
 973                                         # Double-brace expansion
 974                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
 975                                         $titles = $xpath->query( 'title', $contextNode );
 976                                         $title = $titles->item( 0 );
 977                                         $parts = $xpath->query( 'part', $contextNode );
 978                                         if ( $flags & PPFrame::NO_TEMPLATES ) {
 979                                                 $newIterator = $this->virtualBracketedImplode( '{{', '|', '}}', $title, $parts );
 980                                         } else {
 981                                                 $lineStart = $contextNode->getAttribute( 'lineStart' );
 982                                                 $params = array(
 983                                                         'title' => new PPNode_DOM( $title ),
 984                                                         'parts' => new PPNode_DOM( $parts ),
 985                                                         'lineStart' => $lineStart );
 986                                                 $ret = $this->parser->braceSubstitution( $params, $this );
 987                                                 if ( isset( $ret['object'] ) ) {
 988                                                         $newIterator = $ret['object'];
 989                                                 } else {
 990                                                         $out .= $ret['text'];
 991                                                 }
 992                                         }
 993                                 } elseif ( $contextNode->nodeName == 'tplarg' ) {
 994                                         # Triple-brace expansion
 995                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
 996                                         $titles = $xpath->query( 'title', $contextNode );
 997                                         $title = $titles->item( 0 );
 998                                         $parts = $xpath->query( 'part', $contextNode );
 999                                         if ( $flags & PPFrame::NO_ARGS ) {
1000                                                 $newIterator = $this->virtualBracketedImplode( '{{{', '|', '}}}', $title, $parts );
1001                                         } else {
1002                                                 $params = array(
1003                                                         'title' => new PPNode_DOM( $title ),
1004                                                         'parts' => new PPNode_DOM( $parts ) );
1005                                                 $ret = $this->parser->argSubstitution( $params, $this );
1006                                                 if ( isset( $ret['object'] ) ) {
1007                                                         $newIterator = $ret['object'];
1008                                                 } else {
1009                                                         $out .= $ret['text'];
1010                                                 }
1011                                         }
1012                                 } elseif ( $contextNode->nodeName == 'comment' ) {
1013                                         # HTML-style comment
1014                                         # Remove it in HTML, pre+remove and STRIP_COMMENTS modes
1015                                         if ( $this->parser->ot['html']
1016                                                 || ( $this->parser->ot['pre'] && $this->parser->mOptions->getRemoveComments() )
1017                                                 || ( $flags & PPFrame::STRIP_COMMENTS ) )
1018                                         {
1019                                                 $out .= '';
1020                                         }
1021                                         # Add a strip marker in PST mode so that pstPass2() can run some old-fashioned regexes on the result
1022                                         # Not in RECOVER_COMMENTS mode (extractSections) though
1023                                         elseif ( $this->parser->ot['wiki'] && ! ( $flags & PPFrame::RECOVER_COMMENTS ) ) {
1024                                                 $out .= $this->parser->insertStripItem( $contextNode->textContent );
1025                                         }
1026                                         # Recover the literal comment in RECOVER_COMMENTS and pre+no-remove
1027                                         else {
1028                                                 $out .= $contextNode->textContent;
1029                                         }
1030                                 } elseif ( $contextNode->nodeName == 'ignore' ) {
1031                                         # Output suppression used by <includeonly> etc.
1032                                         # OT_WIKI will only respect <ignore> in substed templates.
1033                                         # The other output types respect it unless NO_IGNORE is set.
1034                                         # extractSections() sets NO_IGNORE and so never respects it.
1035                                         if ( ( !isset( $this->parent ) && $this->parser->ot['wiki'] ) || ( $flags & PPFrame::NO_IGNORE ) ) {
1036                                                 $out .= $contextNode->textContent;
1037                                         } else {
1038                                                 $out .= '';
1039                                         }
1040                                 } elseif ( $contextNode->nodeName == 'ext' ) {
1041                                         # Extension tag
1042                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
1043                                         $names = $xpath->query( 'name', $contextNode );
1044                                         $attrs = $xpath->query( 'attr', $contextNode );
1045                                         $inners = $xpath->query( 'inner', $contextNode );
1046                                         $closes = $xpath->query( 'close', $contextNode );
1047                                         $params = array(
1048                                                 'name' => new PPNode_DOM( $names->item( 0 ) ),
1049                                                 'attr' => $attrs->length > 0 ? new PPNode_DOM( $attrs->item( 0 ) ) : null,
1050                                                 'inner' => $inners->length > 0 ? new PPNode_DOM( $inners->item( 0 ) ) : null,
1051                                                 'close' => $closes->length > 0 ? new PPNode_DOM( $closes->item( 0 ) ) : null,
1052                                         );
1053                                         $out .= $this->parser->extensionSubstitution( $params, $this );
1054                                 } elseif ( $contextNode->nodeName == 'h' ) {
1055                                         # Heading
1056                                         $s = $this->expand( $contextNode->childNodes, $flags );
1057
1058                                         # Insert a heading marker only for <h> children of <root>
1059                                         # This is to stop extractSections from going over multiple tree levels
1060                                         if ( $contextNode->parentNode->nodeName == 'root'
1061                                           && $this->parser->ot['html'] )
1062                                         {
1063                                                 # Insert heading index marker
1064                                                 $headingIndex = $contextNode->getAttribute( 'i' );
1065                                                 $titleText = $this->title->getPrefixedDBkey();
1066                                                 $this->parser->mHeadings[] = array( $titleText, $headingIndex );
1067                                                 $serial = count( $this->parser->mHeadings ) - 1;
1068                                                 $marker = "{$this->parser->mUniqPrefix}-h-$serial-" . Parser::MARKER_SUFFIX;
1069                                                 $count = $contextNode->getAttribute( 'level' );
1070                                                 $s = substr( $s, 0, $count ) . $marker . substr( $s, $count );
1071                                                 $this->parser->mStripState->addGeneral( $marker, '' );
1072                                         }
1073                                         $out .= $s;
1074                                 } else {
1075                                         # Generic recursive expansion
1076                                         $newIterator = $contextNode->childNodes;
1077                                 }
1078                         } else {
1079                                 wfProfileOut( __METHOD__ );
1080                                 throw new MWException( __METHOD__.': Invalid parameter type' );
1081                         }
1082
1083                         if ( $newIterator !== false ) {
1084                                 if ( $newIterator instanceof PPNode_DOM ) {
1085                                         $newIterator = $newIterator->node;
1086                                 }
1087                                 $outStack[] = '';
1088                                 $iteratorStack[] = $newIterator;
1089                                 $indexStack[] = 0;
1090                         } elseif ( $iteratorStack[$level] === false ) {
1091                                 // Return accumulated value to parent
1092                                 // With tail recursion
1093                                 while ( $iteratorStack[$level] === false && $level > 0 ) {
1094                                         $outStack[$level - 1] .= $out;
1095                                         array_pop( $outStack );
1096                                         array_pop( $iteratorStack );
1097                                         array_pop( $indexStack );
1098                                         $level--;
1099                                 }
1100                         }
1101                 }
1102                 --$expansionDepth;
1103                 wfProfileOut( __METHOD__ );
1104                 return $outStack[0];
1105         }
1106
1107         function implodeWithFlags( $sep, $flags /*, ... */ ) {
1108                 $args = array_slice( func_get_args(), 2 );
1109
1110                 $first = true;
1111                 $s = '';
1112                 foreach ( $args as $root ) {
1113                         if ( $root instanceof PPNode_DOM ) $root = $root->node;
1114                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1115                                 $root = array( $root );
1116                         }
1117                         foreach ( $root as $node ) {
1118                                 if ( $first ) {
1119                                         $first = false;
1120                                 } else {
1121                                         $s .= $sep;
1122                                 }
1123                                 $s .= $this->expand( $node, $flags );
1124                         }
1125                 }
1126                 return $s;
1127         }
1128
1129         /**
1130          * Implode with no flags specified
1131          * This previously called implodeWithFlags but has now been inlined to reduce stack depth
1132          */
1133         function implode( $sep /*, ... */ ) {
1134                 $args = array_slice( func_get_args(), 1 );
1135
1136                 $first = true;
1137                 $s = '';
1138                 foreach ( $args as $root ) {
1139                         if ( $root instanceof PPNode_DOM ) {
1140                                 $root = $root->node;
1141                         }
1142                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1143                                 $root = array( $root );
1144                         }
1145                         foreach ( $root as $node ) {
1146                                 if ( $first ) {
1147                                         $first = false;
1148                                 } else {
1149                                         $s .= $sep;
1150                                 }
1151                                 $s .= $this->expand( $node );
1152                         }
1153                 }
1154                 return $s;
1155         }
1156
1157         /**
1158          * Makes an object that, when expand()ed, will be the same as one obtained
1159          * with implode()
1160          */
1161         function virtualImplode( $sep /*, ... */ ) {
1162                 $args = array_slice( func_get_args(), 1 );
1163                 $out = array();
1164                 $first = true;
1165
1166                 foreach ( $args as $root ) {
1167                         if ( $root instanceof PPNode_DOM ) {
1168                                 $root = $root->node;
1169                         }
1170                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1171                                 $root = array( $root );
1172                         }
1173                         foreach ( $root as $node ) {
1174                                 if ( $first ) {
1175                                         $first = false;
1176                                 } else {
1177                                         $out[] = $sep;
1178                                 }
1179                                 $out[] = $node;
1180                         }
1181                 }
1182                 return $out;
1183         }
1184
1185         /**
1186          * Virtual implode with brackets
1187          */
1188         function virtualBracketedImplode( $start, $sep, $end /*, ... */ ) {
1189                 $args = array_slice( func_get_args(), 3 );
1190                 $out = array( $start );
1191                 $first = true;
1192
1193                 foreach ( $args as $root ) {
1194                         if ( $root instanceof PPNode_DOM ) {
1195                                 $root = $root->node;
1196                         }
1197                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1198                                 $root = array( $root );
1199                         }
1200                         foreach ( $root as $node ) {
1201                                 if ( $first ) {
1202                                         $first = false;
1203                                 } else {
1204                                         $out[] = $sep;
1205                                 }
1206                                 $out[] = $node;
1207                         }
1208                 }
1209                 $out[] = $end;
1210                 return $out;
1211         }
1212
1213         function __toString() {
1214                 return 'frame{}';
1215         }
1216
1217         function getPDBK( $level = false ) {
1218                 if ( $level === false ) {
1219                         return $this->title->getPrefixedDBkey();
1220                 } else {
1221                         return isset( $this->titleCache[$level] ) ? $this->titleCache[$level] : false;
1222                 }
1223         }
1224
1225         function getArguments() {
1226                 return array();
1227         }
1228
1229         function getNumberedArguments() {
1230                 return array();
1231         }
1232
1233         function getNamedArguments() {
1234                 return array();
1235         }
1236
1237         /**
1238          * Returns true if there are no arguments in this frame
1239          */
1240         function isEmpty() {
1241                 return true;
1242         }
1243
1244         function getArgument( $name ) {
1245                 return false;
1246         }
1247
1248         /**
1249          * Returns true if the infinite loop check is OK, false if a loop is detected
1250          */
1251         function loopCheck( $title ) {
1252                 return !isset( $this->loopCheckHash[$title->getPrefixedDBkey()] );
1253         }
1254
1255         /**
1256          * Return true if the frame is a template frame
1257          */
1258         function isTemplate() {
1259                 return false;
1260         }
1261 }
1262
1263 /**
1264  * Expansion frame with template arguments
1265  * @ingroup Parser
1266  */
1267 class PPTemplateFrame_DOM extends PPFrame_DOM {
1268         var $numberedArgs, $namedArgs, $parent;
1269         var $numberedExpansionCache, $namedExpansionCache;
1270
1271         function __construct( $preprocessor, $parent = false, $numberedArgs = array(), $namedArgs = array(), $title = false ) {
1272                 parent::__construct( $preprocessor );
1273
1274                 $this->parent = $parent;
1275                 $this->numberedArgs = $numberedArgs;
1276                 $this->namedArgs = $namedArgs;
1277                 $this->title = $title;
1278                 $pdbk = $title ? $title->getPrefixedDBkey() : false;
1279                 $this->titleCache = $parent->titleCache;
1280                 $this->titleCache[] = $pdbk;
1281                 $this->loopCheckHash = /*clone*/ $parent->loopCheckHash;
1282                 if ( $pdbk !== false ) {
1283                         $this->loopCheckHash[$pdbk] = true;
1284                 }
1285                 $this->depth = $parent->depth + 1;
1286                 $this->numberedExpansionCache = $this->namedExpansionCache = array();
1287         }
1288
1289         function __toString() {
1290                 $s = 'tplframe{';
1291                 $first = true;
1292                 $args = $this->numberedArgs + $this->namedArgs;
1293                 foreach ( $args as $name => $value ) {
1294                         if ( $first ) {
1295                                 $first = false;
1296                         } else {
1297                                 $s .= ', ';
1298                         }
1299                         $s .= "\"$name\":\"" .
1300                                 str_replace( '"', '\\"', $value->ownerDocument->saveXML( $value ) ) . '"';
1301                 }
1302                 $s .= '}';
1303                 return $s;
1304         }
1305         /**
1306          * Returns true if there are no arguments in this frame
1307          */
1308         function isEmpty() {
1309                 return !count( $this->numberedArgs ) && !count( $this->namedArgs );
1310         }
1311
1312         function getArguments() {
1313                 $arguments = array();
1314                 foreach ( array_merge(
1315                                 array_keys($this->numberedArgs),
1316                                 array_keys($this->namedArgs)) as $key ) {
1317                         $arguments[$key] = $this->getArgument($key);
1318                 }
1319                 return $arguments;
1320         }
1321
1322         function getNumberedArguments() {
1323                 $arguments = array();
1324                 foreach ( array_keys($this->numberedArgs) as $key ) {
1325                         $arguments[$key] = $this->getArgument($key);
1326                 }
1327                 return $arguments;
1328         }
1329
1330         function getNamedArguments() {
1331                 $arguments = array();
1332                 foreach ( array_keys($this->namedArgs) as $key ) {
1333                         $arguments[$key] = $this->getArgument($key);
1334                 }
1335                 return $arguments;
1336         }
1337
1338         function getNumberedArgument( $index ) {
1339                 if ( !isset( $this->numberedArgs[$index] ) ) {
1340                         return false;
1341                 }
1342                 if ( !isset( $this->numberedExpansionCache[$index] ) ) {
1343                         # No trimming for unnamed arguments
1344                         $this->numberedExpansionCache[$index] = $this->parent->expand( $this->numberedArgs[$index], PPFrame::STRIP_COMMENTS );
1345                 }
1346                 return $this->numberedExpansionCache[$index];
1347         }
1348
1349         function getNamedArgument( $name ) {
1350                 if ( !isset( $this->namedArgs[$name] ) ) {
1351                         return false;
1352                 }
1353                 if ( !isset( $this->namedExpansionCache[$name] ) ) {
1354                         # Trim named arguments post-expand, for backwards compatibility
1355                         $this->namedExpansionCache[$name] = trim(
1356                                 $this->parent->expand( $this->namedArgs[$name], PPFrame::STRIP_COMMENTS ) );
1357                 }
1358                 return $this->namedExpansionCache[$name];
1359         }
1360
1361         function getArgument( $name ) {
1362                 $text = $this->getNumberedArgument( $name );
1363                 if ( $text === false ) {
1364                         $text = $this->getNamedArgument( $name );
1365                 }
1366                 return $text;
1367         }
1368
1369         /**
1370          * Return true if the frame is a template frame
1371          */
1372         function isTemplate() {
1373                 return true;
1374         }
1375 }
1376
1377 /**
1378  * Expansion frame with custom arguments
1379  * @ingroup Parser
1380  */
1381 class PPCustomFrame_DOM extends PPFrame_DOM {
1382         var $args;
1383
1384         function __construct( $preprocessor, $args ) {
1385                 parent::__construct( $preprocessor );
1386                 $this->args = $args;
1387         }
1388
1389         function __toString() {
1390                 $s = 'cstmframe{';
1391                 $first = true;
1392                 foreach ( $this->args as $name => $value ) {
1393                         if ( $first ) {
1394                                 $first = false;
1395                         } else {
1396                                 $s .= ', ';
1397                         }
1398                         $s .= "\"$name\":\"" .
1399                                 str_replace( '"', '\\"', $value->__toString() ) . '"';
1400                 }
1401                 $s .= '}';
1402                 return $s;
1403         }
1404
1405         function isEmpty() {
1406                 return !count( $this->args );
1407         }
1408
1409         function getArgument( $index ) {
1410                 if ( !isset( $this->args[$index] ) ) {
1411                         return false;
1412                 }
1413                 return $this->args[$index];
1414         }
1415 }
1416
1417 /**
1418  * @ingroup Parser
1419  */
1420 class PPNode_DOM implements PPNode {
1421         var $node, $xpath;
1422
1423         function __construct( $node, $xpath = false ) {
1424                 $this->node = $node;
1425         }
1426
1427         function getXPath() {
1428                 if ( $this->xpath === null ) {
1429                         $this->xpath = new DOMXPath( $this->node->ownerDocument );
1430                 }
1431                 return $this->xpath;
1432         }
1433
1434         function __toString() {
1435                 if ( $this->node instanceof DOMNodeList ) {
1436                         $s = '';
1437                         foreach ( $this->node as $node ) {
1438                                 $s .= $node->ownerDocument->saveXML( $node );
1439                         }
1440                 } else {
1441                         $s = $this->node->ownerDocument->saveXML( $this->node );
1442                 }
1443                 return $s;
1444         }
1445
1446         function getChildren() {
1447                 return $this->node->childNodes ? new self( $this->node->childNodes ) : false;
1448         }
1449
1450         function getFirstChild() {
1451                 return $this->node->firstChild ? new self( $this->node->firstChild ) : false;
1452         }
1453
1454         function getNextSibling() {
1455                 return $this->node->nextSibling ? new self( $this->node->nextSibling ) : false;
1456         }
1457
1458         function getChildrenOfType( $type ) {
1459                 return new self( $this->getXPath()->query( $type, $this->node ) );
1460         }
1461
1462         function getLength() {
1463                 if ( $this->node instanceof DOMNodeList ) {
1464                         return $this->node->length;
1465                 } else {
1466                         return false;
1467                 }
1468         }
1469
1470         function item( $i ) {
1471                 $item = $this->node->item( $i );
1472                 return $item ? new self( $item ) : false;
1473         }
1474
1475         function getName() {
1476                 if ( $this->node instanceof DOMNodeList ) {
1477                         return '#nodelist';
1478                 } else {
1479                         return $this->node->nodeName;
1480                 }
1481         }
1482
1483         /**
1484          * Split a <part> node into an associative array containing:
1485          *    name          PPNode name
1486          *    index         String index
1487          *    value         PPNode value
1488          */
1489         function splitArg() {
1490                 $xpath = $this->getXPath();
1491                 $names = $xpath->query( 'name', $this->node );
1492                 $values = $xpath->query( 'value', $this->node );
1493                 if ( !$names->length || !$values->length ) {
1494                         throw new MWException( 'Invalid brace node passed to ' . __METHOD__ );
1495                 }
1496                 $name = $names->item( 0 );
1497                 $index = $name->getAttribute( 'index' );
1498                 return array(
1499                         'name' => new self( $name ),
1500                         'index' => $index,
1501                         'value' => new self( $values->item( 0 ) ) );
1502         }
1503
1504         /**
1505          * Split an <ext> node into an associative array containing name, attr, inner and close
1506          * All values in the resulting array are PPNodes. Inner and close are optional.
1507          */
1508         function splitExt() {
1509                 $xpath = $this->getXPath();
1510                 $names = $xpath->query( 'name', $this->node );
1511                 $attrs = $xpath->query( 'attr', $this->node );
1512                 $inners = $xpath->query( 'inner', $this->node );
1513                 $closes = $xpath->query( 'close', $this->node );
1514                 if ( !$names->length || !$attrs->length ) {
1515                         throw new MWException( 'Invalid ext node passed to ' . __METHOD__ );
1516                 }
1517                 $parts = array(
1518                         'name' => new self( $names->item( 0 ) ),
1519                         'attr' => new self( $attrs->item( 0 ) ) );
1520                 if ( $inners->length ) {
1521                         $parts['inner'] = new self( $inners->item( 0 ) );
1522                 }
1523                 if ( $closes->length ) {
1524                         $parts['close'] = new self( $closes->item( 0 ) );
1525                 }
1526                 return $parts;
1527         }
1528
1529         /**
1530          * Split a <h> node
1531          */
1532         function splitHeading() {
1533                 if ( $this->getName() !== 'h' ) {
1534                         throw new MWException( 'Invalid h node passed to ' . __METHOD__ );
1535                 }
1536                 return array(
1537                         'i' => $this->node->getAttribute( 'i' ),
1538                         'level' => $this->node->getAttribute( 'level' ),
1539                         'contents' => $this->getChildren()
1540                 );
1541         }
1542 }