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
  14         /**
  15          * @var Parser
  16          */
  17         var $parser;
  18
  19         var $memoryLimit;
  20
  21         const CACHE_VERSION = 1;
  22
  23         function __construct( $parser ) {
  24                 $this->parser = $parser;
  25                 $mem = ini_get( 'memory_limit' );
  26                 $this->memoryLimit = false;
  27                 if ( strval( $mem ) !== '' && $mem != -1 ) {
  28                         if ( preg_match( '/^\d+$/', $mem ) ) {
  29                                 $this->memoryLimit = $mem;
  30                         } elseif ( preg_match( '/^(\d+)M$/i', $mem, $m ) ) {
  31                                 $this->memoryLimit = $m[1] * 1048576;
  32                         }
  33                 }
  34         }
  35
  36         /**
  37          * @return PPFrame_DOM
  38          */
  39         function newFrame() {
  40                 return new PPFrame_DOM( $this );
  41         }
  42
  43         /**
  44          * @param $args
  45          * @return PPCustomFrame_DOM
  46          */
  47         function newCustomFrame( $args ) {
  48                 return new PPCustomFrame_DOM( $this, $args );
  49         }
  50
  51         /**
  52          * @param $values
  53          * @return PPNode_DOM
  54          */
  55         function newPartNodeArray( $values ) {
  56                 //NOTE: DOM manipulation is slower than building & parsing XML! (or so Tim sais)
  57                 $xml = "<list>";
  58
  59                 foreach ( $values as $k => $val ) {
  60
  61                         if ( is_int( $k ) ) {
  62                                 $xml .= "<part><name index=\"$k\"/><value>" . htmlspecialchars( $val ) ."</value></part>";
  63                         } else {
  64                                 $xml .= "<part><name>" . htmlspecialchars( $k ) . "</name>=<value>" . htmlspecialchars( $val ) . "</value></part>";
  65                         }
  66                 }
  67
  68                 $xml .= "</list>";
  69
  70                 $dom = new DOMDocument();
  71                 $dom->loadXML( $xml );
  72                 $root = $dom->documentElement;
  73
  74                 $node = new PPNode_DOM( $root->childNodes );
  75                 return $node;
  76         }
  77
  78         /**
  79          * @throws MWException
  80          * @return bool
  81          */
  82         function memCheck() {
  83                 if ( $this->memoryLimit === false ) {
  84                         return true;
  85                 }
  86                 $usage = memory_get_usage();
  87                 if ( $usage > $this->memoryLimit * 0.9 ) {
  88                         $limit = intval( $this->memoryLimit * 0.9 / 1048576 + 0.5 );
  89                         throw new MWException( "Preprocessor hit 90% memory limit ($limit MB)" );
  90                 }
  91                 return $usage <= $this->memoryLimit * 0.8;
  92         }
  93
  94         /**
  95          * Preprocess some wikitext and return the document tree.
  96          * This is the ghost of Parser::replace_variables().
  97          *
  98          * @param $text String: the text to parse
  99          * @param $flags Integer: bitwise combination of:
 100          *          Parser::PTD_FOR_INCLUSION    Handle <noinclude>/<includeonly> as if the text is being
 101          *                                     included. Default is to assume a direct page view.
 102          *
 103          * The generated DOM tree must depend only on the input text and the flags.
 104          * The DOM tree must be the same in OT_HTML and OT_WIKI mode, to avoid a regression of bug 4899.
 105          *
 106          * Any flag added to the $flags parameter here, or any other parameter liable to cause a
 107          * change in the DOM tree for a given text, must be passed through the section identifier
 108          * in the section edit link and thus back to extractSections().
 109          *
 110          * The output of this function is currently only cached in process memory, but a persistent
 111          * cache may be implemented at a later date which takes further advantage of these strict
 112          * dependency requirements.
 113          *
 114          * @return PPNode_DOM
 115          */
 116         function preprocessToObj( $text, $flags = 0 ) {
 117                 wfProfileIn( __METHOD__ );
 118                 global $wgMemc, $wgPreprocessorCacheThreshold;
 119
 120                 $xml = false;
 121                 $cacheable = ( $wgPreprocessorCacheThreshold !== false
 122                         && strlen( $text ) > $wgPreprocessorCacheThreshold );
 123                 if ( $cacheable ) {
 124                         wfProfileIn( __METHOD__.'-cacheable' );
 125
 126                         $cacheKey = wfMemcKey( 'preprocess-xml', md5($text), $flags );
 127                         $cacheValue = $wgMemc->get( $cacheKey );
 128                         if ( $cacheValue ) {
 129                                 $version = substr( $cacheValue, 0, 8 );
 130                                 if ( intval( $version ) == self::CACHE_VERSION ) {
 131                                         $xml = substr( $cacheValue, 8 );
 132                                         // From the cache
 133                                         wfDebugLog( "Preprocessor", "Loaded preprocessor XML from memcached (key $cacheKey)" );
 134                                 }
 135                         }
 136                 }
 137                 if ( $xml === false ) {
 138                         if ( $cacheable ) {
 139                                 wfProfileIn( __METHOD__.'-cache-miss' );
 140                                 $xml = $this->preprocessToXml( $text, $flags );
 141                                 $cacheValue = sprintf( "%08d", self::CACHE_VERSION ) . $xml;
 142                                 $wgMemc->set( $cacheKey, $cacheValue, 86400 );
 143                                 wfProfileOut( __METHOD__.'-cache-miss' );
 144                                 wfDebugLog( "Preprocessor", "Saved preprocessor XML to memcached (key $cacheKey)" );
 145                         } else {
 146                                 $xml = $this->preprocessToXml( $text, $flags );
 147                         }
 148
 149                 }
 150                 wfProfileIn( __METHOD__.'-loadXML' );
 151                 $dom = new DOMDocument;
 152                 wfSuppressWarnings();
 153                 $result = $dom->loadXML( $xml );
 154                 wfRestoreWarnings();
 155                 if ( !$result ) {
 156                         // Try running the XML through UtfNormal to get rid of invalid characters
 157                         $xml = UtfNormal::cleanUp( $xml );
 158                         // 1 << 19 == XML_PARSE_HUGE, needed so newer versions of libxml2 don't barf when the XML is >256 levels deep
 159                         $result = $dom->loadXML( $xml, 1 << 19 );
 160                         if ( !$result ) {
 161                                 throw new MWException( __METHOD__.' generated invalid XML' );
 162                         }
 163                 }
 164                 $obj = new PPNode_DOM( $dom->documentElement );
 165                 wfProfileOut( __METHOD__.'-loadXML' );
 166                 if ( $cacheable ) {
 167                         wfProfileOut( __METHOD__.'-cacheable' );
 168                 }
 169                 wfProfileOut( __METHOD__ );
 170                 return $obj;
 171         }
 172
 173         /**
 174          * @param $text string
 175          * @param $flags int
 176          * @return string
 177          */
 178         function preprocessToXml( $text, $flags = 0 ) {
 179                 wfProfileIn( __METHOD__ );
 180                 $rules = array(
 181                         '{' => array(
 182                                 'end' => '}',
 183                                 'names' => array(
 184                                         2 => 'template',
 185                                         3 => 'tplarg',
 186                                 ),
 187                                 'min' => 2,
 188                                 'max' => 3,
 189                         ),
 190                         '[' => array(
 191                                 'end' => ']',
 192                                 'names' => array( 2 => null ),
 193                                 'min' => 2,
 194                                 'max' => 2,
 195                         )
 196                 );
 197
 198                 $forInclusion = $flags & Parser::PTD_FOR_INCLUSION;
 199
 200                 $xmlishElements = $this->parser->getStripList();
 201                 $enableOnlyinclude = false;
 202                 if ( $forInclusion ) {
 203                         $ignoredTags = array( 'includeonly', '/includeonly' );
 204                         $ignoredElements = array( 'noinclude' );
 205                         $xmlishElements[] = 'noinclude';
 206                         if ( strpos( $text, '<onlyinclude>' ) !== false && strpos( $text, '</onlyinclude>' ) !== false ) {
 207                                 $enableOnlyinclude = true;
 208                         }
 209                 } else {
 210                         $ignoredTags = array( 'noinclude', '/noinclude', 'onlyinclude', '/onlyinclude' );
 211                         $ignoredElements = array( 'includeonly' );
 212                         $xmlishElements[] = 'includeonly';
 213                 }
 214                 // `dws' stands for "discard white spaces". `<dws>' and all the whitespaces afer it are
 215                 // discarded.
 216                 $xmlishElements[] = 'dws';
 217                 $xmlishRegex = implode( '|', array_merge( $xmlishElements, $ignoredTags ) );
 218
 219                 // Use "A" modifier (anchored) instead of "^", because ^ doesn't work with an offset
 220                 $elementsRegex = "~($xmlishRegex)(?:\s|\/>|>)|(!--)~iA";
 221
 222                 $stack = new PPDStack;
 223
 224                 $searchBase = "[{<\n"; #}
 225                 $revText = strrev( $text ); // For fast reverse searches
 226
 227                 $i = 0;                     # Input pointer, starts out pointing to a pseudo-newline before the start
 228                 $accum =& $stack->getAccum();   # Current accumulator
 229                 $accum = '<root>';
 230                 $findEquals = false;            # True to find equals signs in arguments
 231                 $findPipe = false;              # True to take notice of pipe characters
 232                 $headingIndex = 1;
 233                 $inHeading = false;        # True if $i is inside a possible heading
 234                 $noMoreGT = false;         # True if there are no more greater-than (>) signs right of $i
 235                 $findOnlyinclude = $enableOnlyinclude; # True to ignore all input up to the next <onlyinclude>
 236                 $fakeLineStart = true;     # Do a line-start run without outputting an LF character
 237
 238                 while ( true ) {
 239                         //$this->memCheck();
 240
 241                         if ( $findOnlyinclude ) {
 242                                 // Ignore all input up to the next <onlyinclude>
 243                                 $startPos = strpos( $text, '<onlyinclude>', $i );
 244                                 if ( $startPos === false ) {
 245                                         // Ignored section runs to the end
 246                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i ) ) . '</ignore>';
 247                                         break;
 248                                 }
 249                                 $tagEndPos = $startPos + strlen( '<onlyinclude>' ); // past-the-end
 250                                 $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i, $tagEndPos - $i ) ) . '</ignore>';
 251                                 $i = $tagEndPos;
 252                                 $findOnlyinclude = false;
 253                         }
 254
 255                         if ( $fakeLineStart ) {
 256                                 $found = 'line-start';
 257                                 $curChar = '';
 258                         } else {
 259                                 # Find next opening brace, closing brace or pipe
 260                                 $search = $searchBase;
 261                                 if ( $stack->top === false ) {
 262                                         $currentClosing = '';
 263                                 } else {
 264                                         $currentClosing = $stack->top->close;
 265                                         $search .= $currentClosing;
 266                                 }
 267                                 if ( $findPipe ) {
 268                                         $search .= '|';
 269                                 }
 270                                 if ( $findEquals ) {
 271                                         // First equals will be for the template
 272                                         $search .= '=';
 273                                 }
 274                                 $rule = null;
 275                                 # Output literal section, advance input counter
 276                                 $literalLength = strcspn( $text, $search, $i );
 277                                 if ( $literalLength > 0 ) {
 278                                         $accum .= htmlspecialchars( substr( $text, $i, $literalLength ) );
 279                                         $i += $literalLength;
 280                                 }
 281                                 if ( $i >= strlen( $text ) ) {
 282                                         if ( $currentClosing == "\n" ) {
 283                                                 // Do a past-the-end run to finish off the heading
 284                                                 $curChar = '';
 285                                                 $found = 'line-end';
 286                                         } else {
 287                                                 # All done
 288                                                 break;
 289                                         }
 290                                 } else {
 291                                         $curChar = $text[$i];
 292                                         if ( $curChar == '|' ) {
 293                                                 $found = 'pipe';
 294                                         } elseif ( $curChar == '=' ) {
 295                                                 $found = 'equals';
 296                                         } elseif ( $curChar == '<' ) {
 297                                                 $found = 'angle';
 298                                         } elseif ( $curChar == "\n" ) {
 299                                                 if ( $inHeading ) {
 300                                                         $found = 'line-end';
 301                                                 } else {
 302                                                         $found = 'line-start';
 303                                                 }
 304                                         } elseif ( $curChar == $currentClosing ) {
 305                                                 $found = 'close';
 306                                         } elseif ( isset( $rules[$curChar] ) ) {
 307                                                 $found = 'open';
 308                                                 $rule = $rules[$curChar];
 309                                         } else {
 310                                                 # Some versions of PHP have a strcspn which stops on null characters
 311                                                 # Ignore and continue
 312                                                 ++$i;
 313                                                 continue;
 314                                         }
 315                                 }
 316                         }
 317
 318                         if ( $found == 'angle' ) {
 319                                 $matches = false;
 320                                 // Handle </onlyinclude>
 321                                 if ( $enableOnlyinclude && substr( $text, $i, strlen( '</onlyinclude>' ) ) == '</onlyinclude>' ) {
 322                                         $findOnlyinclude = true;
 323                                         continue;
 324                                 }
 325
 326                                 // Determine element name
 327                                 if ( !preg_match( $elementsRegex, $text, $matches, 0, $i + 1 ) ) {
 328                                         // Element name missing or not listed
 329                                         $accum .= '&lt;';
 330                                         ++$i;
 331                                         continue;
 332                                 }
 333                                 // Handle comments
 334                                 if ( isset( $matches[2] ) && $matches[2] == '!--' ) {
 335                                         // To avoid leaving blank lines, when a comment is both preceded
 336                                         // and followed by a newline (ignoring spaces), trim leading and
 337                                         // trailing spaces and one of the newlines.
 338
 339                                         // Find the end
 340                                         $endPos = strpos( $text, '-->', $i + 4 );
 341                                         if ( $endPos === false ) {
 342                                                 // Unclosed comment in input, runs to end
 343                                                 $inner = substr( $text, $i );
 344                                                 $accum .= '<comment>' . htmlspecialchars( $inner ) . '</comment>';
 345                                                 $i = strlen( $text );
 346                                         } else {
 347                                                 // Search backwards for leading whitespace
 348                                                 $wsStart = $i ? ( $i - strspn( $revText, ' ', strlen( $text ) - $i ) ) : 0;
 349                                                 // Search forwards for trailing whitespace
 350                                                 // $wsEnd will be the position of the last space (or the '>' if there's none)
 351                                                 $wsEnd = $endPos + 2 + strspn( $text, ' ', $endPos + 3 );
 352                                                 // Eat the line if possible
 353                                                 // TODO: This could theoretically be done if $wsStart == 0, i.e. for comments at
 354                                                 // the overall start. That's not how Sanitizer::removeHTMLcomments() did it, but
 355                                                 // it's a possible beneficial b/c break.
 356                                                 if ( $wsStart > 0 && substr( $text, $wsStart - 1, 1 ) == "\n"
 357                                                         && substr( $text, $wsEnd + 1, 1 ) == "\n" )
 358                                                 {
 359                                                         $startPos = $wsStart;
 360                                                         $endPos = $wsEnd + 1;
 361                                                         // Remove leading whitespace from the end of the accumulator
 362                                                         // Sanity check first though
 363                                                         $wsLength = $i - $wsStart;
 364                                                         if ( $wsLength > 0 && substr( $accum, -$wsLength ) === str_repeat( ' ', $wsLength ) ) {
 365                                                                 $accum = substr( $accum, 0, -$wsLength );
 366                                                         }
 367                                                         // Do a line-start run next time to look for headings after the comment
 368                                                         $fakeLineStart = true;
 369                                                 } else {
 370                                                         // No line to eat, just take the comment itself
 371                                                         $startPos = $i;
 372                                                         $endPos += 2;
 373                                                 }
 374
 375                                                 if ( $stack->top ) {
 376                                                         $part = $stack->top->getCurrentPart();
 377                                                         if ( ! (isset( $part->commentEnd ) && $part->commentEnd == $wsStart - 1 )) {
 378                                                                 $part->visualEnd = $wsStart;
 379                                                         }
 380                                                         // Else comments abutting, no change in visual end
 381                                                         $part->commentEnd = $endPos;
 382                                                 }
 383                                                 $i = $endPos + 1;
 384                                                 $inner = substr( $text, $startPos, $endPos - $startPos + 1 );
 385                                                 $accum .= '<comment>' . htmlspecialchars( $inner ) . '</comment>';
 386                                         }
 387                                         continue;
 388                                 }
 389                                 $name = $matches[1];
 390                                 $lowerName = strtolower( $name );
 391                                 $attrStart = $i + strlen( $name ) + 1;
 392
 393                                 // Find end of tag
 394                                 $tagEndPos = $noMoreGT ? false : strpos( $text, '>', $attrStart );
 395                                 if ( $tagEndPos === false ) {
 396                                         // Infinite backtrack
 397                                         // Disable tag search to prevent worst-case O(N^2) performance
 398                                         $noMoreGT = true;
 399                                         $accum .= '&lt;';
 400                                         ++$i;
 401                                         continue;
 402                                 }
 403
 404                                 // Handle ignored tags
 405                                 if ( in_array( $lowerName, $ignoredTags ) ) {
 406                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i, $tagEndPos - $i + 1 ) ) . '</ignore>';
 407                                         $i = $tagEndPos + 1;
 408                                         continue;
 409                                 }
 410
 411                                 $tagStartPos = $i;
 412
 413                                 // Handle tag `dws'.
 414                                 if ( $name == 'dws' ) {
 415                                         $i = $tagEndPos + 1;
 416                                         if ( preg_match( '/\s*/', $text, $matches, 0, $i ) ) {
 417                                                 $i += strlen( $matches[0] );
 418                                         }
 419                                         $accum .=
 420                                                 '<ignore>' .
 421                                                         htmlspecialchars( substr( $text, $tagStartPos, $i - $tagStartPos ) ) .
 422                                                 '</ignore>';
 423                                         continue;
 424                                 }
 425
 426                                 if ( $text[$tagEndPos-1] == '/' ) {
 427                                         $attrEnd = $tagEndPos - 1;
 428                                         $inner = null;
 429                                         $i = $tagEndPos + 1;
 430                                         $close = '';
 431                                 } else {
 432                                         $attrEnd = $tagEndPos;
 433                                         // Find closing tag
 434                                         if ( preg_match( "/<\/" . preg_quote( $name, '/' ) . "\s*>/i",
 435                                                         $text, $matches, PREG_OFFSET_CAPTURE, $tagEndPos + 1 ) )
 436                                         {
 437                                                 $inner = substr( $text, $tagEndPos + 1, $matches[0][1] - $tagEndPos - 1 );
 438                                                 $i = $matches[0][1] + strlen( $matches[0][0] );
 439                                                 $close = '<close>' . htmlspecialchars( $matches[0][0] ) . '</close>';
 440                                         } else {
 441                                                 // No end tag -- let it run out to the end of the text.
 442                                                 $inner = substr( $text, $tagEndPos + 1 );
 443                                                 $i = strlen( $text );
 444                                                 $close = '';
 445                                         }
 446                                 }
 447                                 // <includeonly> and <noinclude> just become <ignore> tags
 448                                 if ( in_array( $lowerName, $ignoredElements ) ) {
 449                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $tagStartPos, $i - $tagStartPos ) )
 450                                                 . '</ignore>';
 451                                         continue;
 452                                 }
 453
 454                                 $accum .= '<ext>';
 455                                 if ( $attrEnd <= $attrStart ) {
 456                                         $attr = '';
 457                                 } else {
 458                                         $attr = substr( $text, $attrStart, $attrEnd - $attrStart );
 459                                 }
 460                                 $accum .= '<name>' . htmlspecialchars( $name ) . '</name>' .
 461                                         // Note that the attr element contains the whitespace between name and attribute,
 462                                         // this is necessary for precise reconstruction during pre-save transform.
 463                                         '<attr>' . htmlspecialchars( $attr ) . '</attr>';
 464                                 if ( $inner !== null ) {
 465                                         $accum .= '<inner>' . htmlspecialchars( $inner ) . '</inner>';
 466                                 }
 467                                 $accum .= $close . '</ext>';
 468                         } elseif ( $found == 'line-start' ) {
 469                                 // Is this the start of a heading?
 470                                 // Line break belongs before the heading element in any case
 471                                 if ( $fakeLineStart ) {
 472                                         $fakeLineStart = false;
 473                                 } else {
 474                                         $accum .= $curChar;
 475                                         $i++;
 476                                 }
 477
 478                                 $count = strspn( $text, '=', $i, 6 );
 479                                 if ( $count == 1 && $findEquals ) {
 480                                         // DWIM: This looks kind of like a name/value separator
 481                                         // Let's let the equals handler have it and break the potential heading
 482                                         // This is heuristic, but AFAICT the methods for completely correct disambiguation are very complex.
 483                                 } elseif ( $count > 0 ) {
 484                                         $piece = array(
 485                                                 'open' => "\n",
 486                                                 'close' => "\n",
 487                                                 'parts' => array( new PPDPart( str_repeat( '=', $count ) ) ),
 488                                                 'startPos' => $i,
 489                                                 'count' => $count );
 490                                         $stack->push( $piece );
 491                                         $accum =& $stack->getAccum();
 492                                         $flags = $stack->getFlags();
 493                                         extract( $flags );
 494                                         $i += $count;
 495                                 }
 496                         } elseif ( $found == 'line-end' ) {
 497                                 $piece = $stack->top;
 498                                 // A heading must be open, otherwise \n wouldn't have been in the search list
 499                                 assert( $piece->open == "\n" );
 500                                 $part = $piece->getCurrentPart();
 501                                 // Search back through the input to see if it has a proper close
 502                                 // Do this using the reversed string since the other solutions (end anchor, etc.) are inefficient
 503                                 $wsLength = strspn( $revText, " \t", strlen( $text ) - $i );
 504                                 $searchStart = $i - $wsLength;
 505                                 if ( isset( $part->commentEnd ) && $searchStart - 1 == $part->commentEnd ) {
 506                                         // Comment found at line end
 507                                         // Search for equals signs before the comment
 508                                         $searchStart = $part->visualEnd;
 509                                         $searchStart -= strspn( $revText, " \t", strlen( $text ) - $searchStart );
 510                                 }
 511                                 $count = $piece->count;
 512                                 $equalsLength = strspn( $revText, '=', strlen( $text ) - $searchStart );
 513                                 if ( $equalsLength > 0 ) {
 514                                         if ( $searchStart - $equalsLength == $piece->startPos ) {
 515                                                 // This is just a single string of equals signs on its own line
 516                                                 // Replicate the doHeadings behaviour /={count}(.+)={count}/
 517                                                 // First find out how many equals signs there really are (don't stop at 6)
 518                                                 $count = $equalsLength;
 519                                                 if ( $count < 3 ) {
 520                                                         $count = 0;
 521                                                 } else {
 522                                                         $count = min( 6, intval( ( $count - 1 ) / 2 ) );
 523                                                 }
 524                                         } else {
 525                                                 $count = min( $equalsLength, $count );
 526                                         }
 527                                         if ( $count > 0 ) {
 528                                                 // Normal match, output <h>
 529                                                 $element = "<h level=\"$count\" i=\"$headingIndex\">$accum</h>";
 530                                                 $headingIndex++;
 531                                         } else {
 532                                                 // Single equals sign on its own line, count=0
 533                                                 $element = $accum;
 534                                         }
 535                                 } else {
 536                                         // No match, no <h>, just pass down the inner text
 537                                         $element = $accum;
 538                                 }
 539                                 // Unwind the stack
 540                                 $stack->pop();
 541                                 $accum =& $stack->getAccum();
 542                                 $flags = $stack->getFlags();
 543                                 extract( $flags );
 544
 545                                 // Append the result to the enclosing accumulator
 546                                 $accum .= $element;
 547                                 // Note that we do NOT increment the input pointer.
 548                                 // This is because the closing linebreak could be the opening linebreak of
 549                                 // another heading. Infinite loops are avoided because the next iteration MUST
 550                                 // hit the heading open case above, which unconditionally increments the
 551                                 // input pointer.
 552                         } elseif ( $found == 'open' ) {
 553                                 # count opening brace characters
 554                                 $count = strspn( $text, $curChar, $i );
 555
 556                                 # we need to add to stack only if opening brace count is enough for one of the rules
 557                                 if ( $count >= $rule['min'] ) {
 558                                         # Add it to the stack
 559                                         $piece = array(
 560                                                 'open' => $curChar,
 561                                                 'close' => $rule['end'],
 562                                                 'count' => $count,
 563                                                 'lineStart' => ($i > 0 && $text[$i-1] == "\n"),
 564                                         );
 565
 566                                         $stack->push( $piece );
 567                                         $accum =& $stack->getAccum();
 568                                         $flags = $stack->getFlags();
 569                                         extract( $flags );
 570                                 } else {
 571                                         # Add literal brace(s)
 572                                         $accum .= htmlspecialchars( str_repeat( $curChar, $count ) );
 573                                 }
 574                                 $i += $count;
 575                         } elseif ( $found == 'close' ) {
 576                                 $piece = $stack->top;
 577                                 # lets check if there are enough characters for closing brace
 578                                 $maxCount = $piece->count;
 579                                 $count = strspn( $text, $curChar, $i, $maxCount );
 580
 581                                 # check for maximum matching characters (if there are 5 closing
 582                                 # characters, we will probably need only 3 - depending on the rules)
 583                                 $rule = $rules[$piece->open];
 584                                 if ( $count > $rule['max'] ) {
 585                                         # The specified maximum exists in the callback array, unless the caller
 586                                         # has made an error
 587                                         $matchingCount = $rule['max'];
 588                                 } else {
 589                                         # Count is less than the maximum
 590                                         # Skip any gaps in the callback array to find the true largest match
 591                                         # Need to use array_key_exists not isset because the callback can be null
 592                                         $matchingCount = $count;
 593                                         while ( $matchingCount > 0 && !array_key_exists( $matchingCount, $rule['names'] ) ) {
 594                                                 --$matchingCount;
 595                                         }
 596                                 }
 597
 598                                 if ( $matchingCount <= 0 ) {
 599                                         # No matching element found in callback array
 600                                         # Output a literal closing brace and continue
 601                                         $accum .= htmlspecialchars( str_repeat( $curChar, $count ) );
 602                                         $i += $count;
 603                                         continue;
 604                                 }
 605                                 $name = $rule['names'][$matchingCount];
 606                                 if ( $name === null ) {
 607                                         // No element, just literal text
 608                                         $element = $piece->breakSyntax( $matchingCount ) . str_repeat( $rule['end'], $matchingCount );
 609                                 } else {
 610                                         # Create XML element
 611                                         # Note: $parts is already XML, does not need to be encoded further
 612                                         $parts = $piece->parts;
 613                                         $title = $parts[0]->out;
 614                                         unset( $parts[0] );
 615
 616                                         # The invocation is at the start of the line if lineStart is set in
 617                                         # the stack, and all opening brackets are used up.
 618                                         if ( $maxCount == $matchingCount && !empty( $piece->lineStart ) ) {
 619                                                 $attr = ' lineStart="1"';
 620                                         } else {
 621                                                 $attr = '';
 622                                         }
 623
 624                                         $element = "<$name$attr>";
 625                                         $element .= "<title>$title</title>";
 626                                         $argIndex = 1;
 627                                         foreach ( $parts as $part ) {
 628                                                 if ( isset( $part->eqpos ) ) {
 629                                                         $argName = substr( $part->out, 0, $part->eqpos );
 630                                                         $argValue = substr( $part->out, $part->eqpos + 1 );
 631                                                         $element .= "<part><name>$argName</name>=<value>$argValue</value></part>";
 632                                                 } else {
 633                                                         $element .= "<part><name index=\"$argIndex\" /><value>{$part->out}</value></part>";
 634                                                         $argIndex++;
 635                                                 }
 636                                         }
 637                                         $element .= "</$name>";
 638                                 }
 639
 640                                 # Advance input pointer
 641                                 $i += $matchingCount;
 642
 643                                 # Unwind the stack
 644                                 $stack->pop();
 645                                 $accum =& $stack->getAccum();
 646
 647                                 # Re-add the old stack element if it still has unmatched opening characters remaining
 648                                 if ( $matchingCount < $piece->count ) {
 649                                         $piece->parts = array( new PPDPart );
 650                                         $piece->count -= $matchingCount;
 651                                         # do we still qualify for any callback with remaining count?
 652                                         $names = $rules[$piece->open]['names'];
 653                                         $skippedBraces = 0;
 654                                         $enclosingAccum =& $accum;
 655                                         while ( $piece->count ) {
 656                                                 if ( array_key_exists( $piece->count, $names ) ) {
 657                                                         $stack->push( $piece );
 658                                                         $accum =& $stack->getAccum();
 659                                                         break;
 660                                                 }
 661                                                 --$piece->count;
 662                                                 $skippedBraces ++;
 663                                         }
 664                                         $enclosingAccum .= str_repeat( $piece->open, $skippedBraces );
 665                                 }
 666                                 $flags = $stack->getFlags();
 667                                 extract( $flags );
 668
 669                                 # Add XML element to the enclosing accumulator
 670                                 $accum .= $element;
 671                         } elseif ( $found == 'pipe' ) {
 672                                 $findEquals = true; // shortcut for getFlags()
 673                                 $stack->addPart();
 674                                 $accum =& $stack->getAccum();
 675                                 ++$i;
 676                         } elseif ( $found == 'equals' ) {
 677                                 $findEquals = false; // shortcut for getFlags()
 678                                 $stack->getCurrentPart()->eqpos = strlen( $accum );
 679                                 $accum .= '=';
 680                                 ++$i;
 681                         }
 682                 }
 683
 684                 # Output any remaining unclosed brackets
 685                 foreach ( $stack->stack as $piece ) {
 686                         $stack->rootAccum .= $piece->breakSyntax();
 687                 }
 688                 $stack->rootAccum .= '</root>';
 689                 $xml = $stack->rootAccum;
 690
 691                 wfProfileOut( __METHOD__ );
 692
 693                 return $xml;
 694         }
 695 }
 696
 697 /**
 698  * Stack class to help Preprocessor::preprocessToObj()
 699  * @ingroup Parser
 700  */
 701 class PPDStack {
 702         var $stack, $rootAccum;
 703
 704         /**
 705          * @var PPDStack
 706          */
 707         var $top;
 708         var $out;
 709         var $elementClass = 'PPDStackElement';
 710
 711         static $false = false;
 712
 713         function __construct() {
 714                 $this->stack = array();
 715                 $this->top = false;
 716                 $this->rootAccum = '';
 717                 $this->accum =& $this->rootAccum;
 718         }
 719
 720         /**
 721          * @return int
 722          */
 723         function count() {
 724                 return count( $this->stack );
 725         }
 726
 727         function &getAccum() {
 728                 return $this->accum;
 729         }
 730
 731         function getCurrentPart() {
 732                 if ( $this->top === false ) {
 733                         return false;
 734                 } else {
 735                         return $this->top->getCurrentPart();
 736                 }
 737         }
 738
 739         function push( $data ) {
 740                 if ( $data instanceof $this->elementClass ) {
 741                         $this->stack[] = $data;
 742                 } else {
 743                         $class = $this->elementClass;
 744                         $this->stack[] = new $class( $data );
 745                 }
 746                 $this->top = $this->stack[ count( $this->stack ) - 1 ];
 747                 $this->accum =& $this->top->getAccum();
 748         }
 749
 750         function pop() {
 751                 if ( !count( $this->stack ) ) {
 752                         throw new MWException( __METHOD__.': no elements remaining' );
 753                 }
 754                 $temp = array_pop( $this->stack );
 755
 756                 if ( count( $this->stack ) ) {
 757                         $this->top = $this->stack[ count( $this->stack ) - 1 ];
 758                         $this->accum =& $this->top->getAccum();
 759                 } else {
 760                         $this->top = self::$false;
 761                         $this->accum =& $this->rootAccum;
 762                 }
 763                 return $temp;
 764         }
 765
 766         function addPart( $s = '' ) {
 767                 $this->top->addPart( $s );
 768                 $this->accum =& $this->top->getAccum();
 769         }
 770
 771         /**
 772          * @return array
 773          */
 774         function getFlags() {
 775                 if ( !count( $this->stack ) ) {
 776                         return array(
 777                                 'findEquals' => false,
 778                                 'findPipe' => false,
 779                                 'inHeading' => false,
 780                         );
 781                 } else {
 782                         return $this->top->getFlags();
 783                 }
 784         }
 785 }
 786
 787 /**
 788  * @ingroup Parser
 789  */
 790 class PPDStackElement {
 791         var $open,                      // Opening character (\n for heading)
 792                 $close,             // Matching closing character
 793                 $count,             // Number of opening characters found (number of "=" for heading)
 794                 $parts,             // Array of PPDPart objects describing pipe-separated parts.
 795                 $lineStart;         // True if the open char appeared at the start of the input line. Not set for headings.
 796
 797         var $partClass = 'PPDPart';
 798
 799         function __construct( $data = array() ) {
 800                 $class = $this->partClass;
 801                 $this->parts = array( new $class );
 802
 803                 foreach ( $data as $name => $value ) {
 804                         $this->$name = $value;
 805                 }
 806         }
 807
 808         function &getAccum() {
 809                 return $this->parts[count($this->parts) - 1]->out;
 810         }
 811
 812         function addPart( $s = '' ) {
 813                 $class = $this->partClass;
 814                 $this->parts[] = new $class( $s );
 815         }
 816
 817         function getCurrentPart() {
 818                 return $this->parts[count($this->parts) - 1];
 819         }
 820
 821         /**
 822          * @return array
 823          */
 824         function getFlags() {
 825                 $partCount = count( $this->parts );
 826                 $findPipe = $this->open != "\n" && $this->open != '[';
 827                 return array(
 828                         'findPipe' => $findPipe,
 829                         'findEquals' => $findPipe && $partCount > 1 && !isset( $this->parts[$partCount - 1]->eqpos ),
 830                         'inHeading' => $this->open == "\n",
 831                 );
 832         }
 833
 834         /**
 835          * Get the output string that would result if the close is not found.
 836          *
 837          * @return string
 838          */
 839         function breakSyntax( $openingCount = false ) {
 840                 if ( $this->open == "\n" ) {
 841                         $s = $this->parts[0]->out;
 842                 } else {
 843                         if ( $openingCount === false ) {
 844                                 $openingCount = $this->count;
 845                         }
 846                         $s = str_repeat( $this->open, $openingCount );
 847                         $first = true;
 848                         foreach ( $this->parts as $part ) {
 849                                 if ( $first ) {
 850                                         $first = false;
 851                                 } else {
 852                                         $s .= '|';
 853                                 }
 854                                 $s .= $part->out;
 855                         }
 856                 }
 857                 return $s;
 858         }
 859 }
 860
 861 /**
 862  * @ingroup Parser
 863  */
 864 class PPDPart {
 865         var $out; // Output accumulator string
 866
 867         // Optional member variables:
 868         //   eqpos        Position of equals sign in output accumulator
 869         //   commentEnd   Past-the-end input pointer for the last comment encountered
 870         //   visualEnd    Past-the-end input pointer for the end of the accumulator minus comments
 871
 872         function __construct( $out = '' ) {
 873                 $this->out = $out;
 874         }
 875 }
 876
 877 /**
 878  * An expansion frame, used as a context to expand the result of preprocessToObj()
 879  * @ingroup Parser
 880  */
 881 class PPFrame_DOM implements PPFrame {
 882
 883         /**
 884          * @var Preprocessor
 885          */
 886         var $preprocessor;
 887
 888         /**
 889          * @var Parser
 890          */
 891         var $parser;
 892
 893         /**
 894          * @var Title
 895          */
 896         var $title;
 897         var $titleCache;
 898
 899         /**
 900          * Hashtable listing templates which are disallowed for expansion in this frame,
 901          * having been encountered previously in parent frames.
 902          */
 903         var $loopCheckHash;
 904
 905         /**
 906          * Recursion depth of this frame, top = 0
 907          * Note that this is NOT the same as expansion depth in expand()
 908          */
 909         var $depth;
 910
 911
 912         /**
 913          * Construct a new preprocessor frame.
 914          * @param $preprocessor Preprocessor The parent preprocessor
 915          */
 916         function __construct( $preprocessor ) {
 917                 $this->preprocessor = $preprocessor;
 918                 $this->parser = $preprocessor->parser;
 919                 $this->title = $this->parser->mTitle;
 920                 $this->titleCache = array( $this->title ? $this->title->getPrefixedDBkey() : false );
 921                 $this->loopCheckHash = array();
 922                 $this->depth = 0;
 923         }
 924
 925         /**
 926          * Create a new child frame
 927          * $args is optionally a multi-root PPNode or array containing the template arguments
 928          *
 929          * @return PPTemplateFrame_DOM
 930          */
 931         function newChild( $args = false, $title = false ) {
 932                 $namedArgs = array();
 933                 $numberedArgs = array();
 934                 if ( $title === false ) {
 935                         $title = $this->title;
 936                 }
 937                 if ( $args !== false ) {
 938                         $xpath = false;
 939                         if ( $args instanceof PPNode ) {
 940                                 $args = $args->node;
 941                         }
 942                         foreach ( $args as $arg ) {
 943                                 if ( !$xpath ) {
 944                                         $xpath = new DOMXPath( $arg->ownerDocument );
 945                                 }
 946
 947                                 $nameNodes = $xpath->query( 'name', $arg );
 948                                 $value = $xpath->query( 'value', $arg );
 949                                 if ( $nameNodes->item( 0 )->hasAttributes() ) {
 950                                         // Numbered parameter
 951                                         $index = $nameNodes->item( 0 )->attributes->getNamedItem( 'index' )->textContent;
 952                                         $numberedArgs[$index] = $value->item( 0 );
 953                                         unset( $namedArgs[$index] );
 954                                 } else {
 955                                         // Named parameter
 956                                         $name = trim( $this->expand( $nameNodes->item( 0 ), PPFrame::STRIP_COMMENTS ) );
 957                                         $namedArgs[$name] = $value->item( 0 );
 958                                         unset( $numberedArgs[$name] );
 959                                 }
 960                         }
 961                 }
 962                 return new PPTemplateFrame_DOM( $this->preprocessor, $this, $numberedArgs, $namedArgs, $title );
 963         }
 964
 965         /**
 966          * @throws MWException
 967          * @param $root
 968          * @param $flags int
 969          * @return string
 970          */
 971         function expand( $root, $flags = 0 ) {
 972                 static $expansionDepth = 0;
 973                 if ( is_string( $root ) ) {
 974                         return $root;
 975                 }
 976
 977                 if ( ++$this->parser->mPPNodeCount > $this->parser->mOptions->getMaxPPNodeCount() ) {
 978                         return '<span class="error">Node-count limit exceeded</span>';
 979                 }
 980
 981                 if ( $expansionDepth > $this->parser->mOptions->getMaxPPExpandDepth() ) {
 982                         return '<span class="error">Expansion depth limit exceeded</span>';
 983                 }
 984                 wfProfileIn( __METHOD__ );
 985                 ++$expansionDepth;
 986
 987                 if ( $root instanceof PPNode_DOM ) {
 988                         $root = $root->node;
 989                 }
 990                 if ( $root instanceof DOMDocument ) {
 991                         $root = $root->documentElement;
 992                 }
 993
 994                 $outStack = array( '', '' );
 995                 $iteratorStack = array( false, $root );
 996                 $indexStack = array( 0, 0 );
 997
 998                 while ( count( $iteratorStack ) > 1 ) {
 999                         $level = count( $outStack ) - 1;
1000                         $iteratorNode =& $iteratorStack[ $level ];
1001                         $out =& $outStack[$level];
1002                         $index =& $indexStack[$level];
1003
1004                         if ( $iteratorNode instanceof PPNode_DOM ) $iteratorNode = $iteratorNode->node;
1005
1006                         if ( is_array( $iteratorNode ) ) {
1007                                 if ( $index >= count( $iteratorNode ) ) {
1008                                         // All done with this iterator
1009                                         $iteratorStack[$level] = false;
1010                                         $contextNode = false;
1011                                 } else {
1012                                         $contextNode = $iteratorNode[$index];
1013                                         $index++;
1014                                 }
1015                         } elseif ( $iteratorNode instanceof DOMNodeList ) {
1016                                 if ( $index >= $iteratorNode->length ) {
1017                                         // All done with this iterator
1018                                         $iteratorStack[$level] = false;
1019                                         $contextNode = false;
1020                                 } else {
1021                                         $contextNode = $iteratorNode->item( $index );
1022                                         $index++;
1023                                 }
1024                         } else {
1025                                 // Copy to $contextNode and then delete from iterator stack,
1026                                 // because this is not an iterator but we do have to execute it once
1027                                 $contextNode = $iteratorStack[$level];
1028                                 $iteratorStack[$level] = false;
1029                         }
1030
1031                         if ( $contextNode instanceof PPNode_DOM ) {
1032                                 $contextNode = $contextNode->node;
1033                         }
1034
1035                         $newIterator = false;
1036
1037                         if ( $contextNode === false ) {
1038                                 // nothing to do
1039                         } elseif ( is_string( $contextNode ) ) {
1040                                 $out .= $contextNode;
1041                         } elseif ( is_array( $contextNode ) || $contextNode instanceof DOMNodeList ) {
1042                                 $newIterator = $contextNode;
1043                         } elseif ( $contextNode instanceof DOMNode ) {
1044                                 if ( $contextNode->nodeType == XML_TEXT_NODE ) {
1045                                         $out .= $contextNode->nodeValue;
1046                                 } elseif ( $contextNode->nodeName == 'template' ) {
1047                                         # Double-brace expansion
1048                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
1049                                         $titles = $xpath->query( 'title', $contextNode );
1050                                         $title = $titles->item( 0 );
1051                                         $parts = $xpath->query( 'part', $contextNode );
1052                                         if ( $flags & PPFrame::NO_TEMPLATES ) {
1053                                                 $newIterator = $this->virtualBracketedImplode( '{{', '|', '}}', $title, $parts );
1054                                         } else {
1055                                                 $lineStart = $contextNode->getAttribute( 'lineStart' );
1056                                                 $params = array(
1057                                                         'title' => new PPNode_DOM( $title ),
1058                                                         'parts' => new PPNode_DOM( $parts ),
1059                                                         'lineStart' => $lineStart );
1060                                                 $ret = $this->parser->braceSubstitution( $params, $this );
1061                                                 if ( isset( $ret['object'] ) ) {
1062                                                         $newIterator = $ret['object'];
1063                                                 } else {
1064                                                         $out .= $ret['text'];
1065                                                 }
1066                                         }
1067                                 } elseif ( $contextNode->nodeName == 'tplarg' ) {
1068                                         # Triple-brace expansion
1069                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
1070                                         $titles = $xpath->query( 'title', $contextNode );
1071                                         $title = $titles->item( 0 );
1072                                         $parts = $xpath->query( 'part', $contextNode );
1073                                         if ( $flags & PPFrame::NO_ARGS ) {
1074                                                 $newIterator = $this->virtualBracketedImplode( '{{{', '|', '}}}', $title, $parts );
1075                                         } else {
1076                                                 $params = array(
1077                                                         'title' => new PPNode_DOM( $title ),
1078                                                         'parts' => new PPNode_DOM( $parts ) );
1079                                                 $ret = $this->parser->argSubstitution( $params, $this );
1080                                                 if ( isset( $ret['object'] ) ) {
1081                                                         $newIterator = $ret['object'];
1082                                                 } else {
1083                                                         $out .= $ret['text'];
1084                                                 }
1085                                         }
1086                                 } elseif ( $contextNode->nodeName == 'comment' ) {
1087                                         # HTML-style comment
1088                                         # Remove it in HTML, pre+remove and STRIP_COMMENTS modes
1089                                         if ( $this->parser->ot['html']
1090                                                 || ( $this->parser->ot['pre'] && $this->parser->mOptions->getRemoveComments() )
1091                                                 || ( $flags & PPFrame::STRIP_COMMENTS ) )
1092                                         {
1093                                                 $out .= '';
1094                                         }
1095                                         # Add a strip marker in PST mode so that pstPass2() can run some old-fashioned regexes on the result
1096                                         # Not in RECOVER_COMMENTS mode (extractSections) though
1097                                         elseif ( $this->parser->ot['wiki'] && ! ( $flags & PPFrame::RECOVER_COMMENTS ) ) {
1098                                                 $out .= $this->parser->insertStripItem( $contextNode->textContent );
1099                                         }
1100                                         # Recover the literal comment in RECOVER_COMMENTS and pre+no-remove
1101                                         else {
1102                                                 $out .= $contextNode->textContent;
1103                                         }
1104                                 } elseif ( $contextNode->nodeName == 'ignore' ) {
1105                                         # Output suppression used by <includeonly> etc.
1106                                         # OT_WIKI will only respect <ignore> in substed templates.
1107                                         # The other output types respect it unless NO_IGNORE is set.
1108                                         # extractSections() sets NO_IGNORE and so never respects it.
1109                                         if ( ( !isset( $this->parent ) && $this->parser->ot['wiki'] ) || ( $flags & PPFrame::NO_IGNORE ) ) {
1110                                                 $out .= $contextNode->textContent;
1111                                         } else {
1112                                                 $out .= '';
1113                                         }
1114                                 } elseif ( $contextNode->nodeName == 'ext' ) {
1115                                         # Extension tag
1116                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
1117                                         $names = $xpath->query( 'name', $contextNode );
1118                                         $attrs = $xpath->query( 'attr', $contextNode );
1119                                         $inners = $xpath->query( 'inner', $contextNode );
1120                                         $closes = $xpath->query( 'close', $contextNode );
1121                                         $params = array(
1122                                                 'name' => new PPNode_DOM( $names->item( 0 ) ),
1123                                                 'attr' => $attrs->length > 0 ? new PPNode_DOM( $attrs->item( 0 ) ) : null,
1124                                                 'inner' => $inners->length > 0 ? new PPNode_DOM( $inners->item( 0 ) ) : null,
1125                                                 'close' => $closes->length > 0 ? new PPNode_DOM( $closes->item( 0 ) ) : null,
1126                                         );
1127                                         $out .= $this->parser->extensionSubstitution( $params, $this );
1128                                 } elseif ( $contextNode->nodeName == 'h' ) {
1129                                         # Heading
1130                                         $s = $this->expand( $contextNode->childNodes, $flags );
1131
1132                                         # Insert a heading marker only for <h> children of <root>
1133                                         # This is to stop extractSections from going over multiple tree levels
1134                                         if ( $contextNode->parentNode->nodeName == 'root'
1135                                           && $this->parser->ot['html'] )
1136                                         {
1137                                                 # Insert heading index marker
1138                                                 $headingIndex = $contextNode->getAttribute( 'i' );
1139                                                 $titleText = $this->title->getPrefixedDBkey();
1140                                                 $this->parser->mHeadings[] = array( $titleText, $headingIndex );
1141                                                 $serial = count( $this->parser->mHeadings ) - 1;
1142                                                 $marker = "{$this->parser->mUniqPrefix}-h-$serial-" . Parser::MARKER_SUFFIX;
1143                                                 $count = $contextNode->getAttribute( 'level' );
1144                                                 $s = substr( $s, 0, $count ) . $marker . substr( $s, $count );
1145                                                 $this->parser->mStripState->addGeneral( $marker, '' );
1146                                         }
1147                                         $out .= $s;
1148                                 } else {
1149                                         # Generic recursive expansion
1150                                         $newIterator = $contextNode->childNodes;
1151                                 }
1152                         } else {
1153                                 wfProfileOut( __METHOD__ );
1154                                 throw new MWException( __METHOD__.': Invalid parameter type' );
1155                         }
1156
1157                         if ( $newIterator !== false ) {
1158                                 if ( $newIterator instanceof PPNode_DOM ) {
1159                                         $newIterator = $newIterator->node;
1160                                 }
1161                                 $outStack[] = '';
1162                                 $iteratorStack[] = $newIterator;
1163                                 $indexStack[] = 0;
1164                         } elseif ( $iteratorStack[$level] === false ) {
1165                                 // Return accumulated value to parent
1166                                 // With tail recursion
1167                                 while ( $iteratorStack[$level] === false && $level > 0 ) {
1168                                         $outStack[$level - 1] .= $out;
1169                                         array_pop( $outStack );
1170                                         array_pop( $iteratorStack );
1171                                         array_pop( $indexStack );
1172                                         $level--;
1173                                 }
1174                         }
1175                 }
1176                 --$expansionDepth;
1177                 wfProfileOut( __METHOD__ );
1178                 return $outStack[0];
1179         }
1180
1181         /**
1182          * @param $sep
1183          * @param $flags
1184          * @return string
1185          */
1186         function implodeWithFlags( $sep, $flags /*, ... */ ) {
1187                 $args = array_slice( func_get_args(), 2 );
1188
1189                 $first = true;
1190                 $s = '';
1191                 foreach ( $args as $root ) {
1192                         if ( $root instanceof PPNode_DOM ) $root = $root->node;
1193                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1194                                 $root = array( $root );
1195                         }
1196                         foreach ( $root as $node ) {
1197                                 if ( $first ) {
1198                                         $first = false;
1199                                 } else {
1200                                         $s .= $sep;
1201                                 }
1202                                 $s .= $this->expand( $node, $flags );
1203                         }
1204                 }
1205                 return $s;
1206         }
1207
1208         /**
1209          * Implode with no flags specified
1210          * This previously called implodeWithFlags but has now been inlined to reduce stack depth
1211          *
1212          * @return string
1213          */
1214         function implode( $sep /*, ... */ ) {
1215                 $args = array_slice( func_get_args(), 1 );
1216
1217                 $first = true;
1218                 $s = '';
1219                 foreach ( $args as $root ) {
1220                         if ( $root instanceof PPNode_DOM ) {
1221                                 $root = $root->node;
1222                         }
1223                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1224                                 $root = array( $root );
1225                         }
1226                         foreach ( $root as $node ) {
1227                                 if ( $first ) {
1228                                         $first = false;
1229                                 } else {
1230                                         $s .= $sep;
1231                                 }
1232                                 $s .= $this->expand( $node );
1233                         }
1234                 }
1235                 return $s;
1236         }
1237
1238         /**
1239          * Makes an object that, when expand()ed, will be the same as one obtained
1240          * with implode()
1241          *
1242          * @return array
1243          */
1244         function virtualImplode( $sep /*, ... */ ) {
1245                 $args = array_slice( func_get_args(), 1 );
1246                 $out = array();
1247                 $first = true;
1248
1249                 foreach ( $args as $root ) {
1250                         if ( $root instanceof PPNode_DOM ) {
1251                                 $root = $root->node;
1252                         }
1253                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1254                                 $root = array( $root );
1255                         }
1256                         foreach ( $root as $node ) {
1257                                 if ( $first ) {
1258                                         $first = false;
1259                                 } else {
1260                                         $out[] = $sep;
1261                                 }
1262                                 $out[] = $node;
1263                         }
1264                 }
1265                 return $out;
1266         }
1267
1268         /**
1269          * Virtual implode with brackets
1270          */
1271         function virtualBracketedImplode( $start, $sep, $end /*, ... */ ) {
1272                 $args = array_slice( func_get_args(), 3 );
1273                 $out = array( $start );
1274                 $first = true;
1275
1276                 foreach ( $args as $root ) {
1277                         if ( $root instanceof PPNode_DOM ) {
1278                                 $root = $root->node;
1279                         }
1280                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1281                                 $root = array( $root );
1282                         }
1283                         foreach ( $root as $node ) {
1284                                 if ( $first ) {
1285                                         $first = false;
1286                                 } else {
1287                                         $out[] = $sep;
1288                                 }
1289                                 $out[] = $node;
1290                         }
1291                 }
1292                 $out[] = $end;
1293                 return $out;
1294         }
1295
1296         function __toString() {
1297                 return 'frame{}';
1298         }
1299
1300         function getPDBK( $level = false ) {
1301                 if ( $level === false ) {
1302                         return $this->title->getPrefixedDBkey();
1303                 } else {
1304                         return isset( $this->titleCache[$level] ) ? $this->titleCache[$level] : false;
1305                 }
1306         }
1307
1308         /**
1309          * @return array
1310          */
1311         function getArguments() {
1312                 return array();
1313         }
1314
1315         /**
1316          * @return array
1317          */
1318         function getNumberedArguments() {
1319                 return array();
1320         }
1321
1322         /**
1323          * @return array
1324          */
1325         function getNamedArguments() {
1326                 return array();
1327         }
1328
1329         /**
1330          * Returns true if there are no arguments in this frame
1331          *
1332          * @return bool
1333          */
1334         function isEmpty() {
1335                 return true;
1336         }
1337
1338         function getArgument( $name ) {
1339                 return false;
1340         }
1341
1342         /**
1343          * Returns true if the infinite loop check is OK, false if a loop is detected
1344          *
1345          * @return bool
1346          */
1347         function loopCheck( $title ) {
1348                 return !isset( $this->loopCheckHash[$title->getPrefixedDBkey()] );
1349         }
1350
1351         /**
1352          * Return true if the frame is a template frame
1353          *
1354          * @return bool
1355          */
1356         function isTemplate() {
1357                 return false;
1358         }
1359
1360         /**
1361          * Get a title of frame
1362          *
1363          * @return Title
1364          */
1365         function getTitle() {
1366                 return $this->title;
1367         }
1368 }
1369
1370 /**
1371  * Expansion frame with template arguments
1372  * @ingroup Parser
1373  */
1374 class PPTemplateFrame_DOM extends PPFrame_DOM {
1375         var $numberedArgs, $namedArgs;
1376
1377         /**
1378          * @var PPFrame_DOM
1379          */
1380         var $parent;
1381         var $numberedExpansionCache, $namedExpansionCache;
1382
1383         /**
1384          * @param $preprocessor
1385          * @param $parent PPFrame_DOM
1386          * @param $numberedArgs array
1387          * @param $namedArgs array
1388          * @param $title Title
1389          */
1390         function __construct( $preprocessor, $parent = false, $numberedArgs = array(), $namedArgs = array(), $title = false ) {
1391                 parent::__construct( $preprocessor );
1392
1393                 $this->parent = $parent;
1394                 $this->numberedArgs = $numberedArgs;
1395                 $this->namedArgs = $namedArgs;
1396                 $this->title = $title;
1397                 $pdbk = $title ? $title->getPrefixedDBkey() : false;
1398                 $this->titleCache = $parent->titleCache;
1399                 $this->titleCache[] = $pdbk;
1400                 $this->loopCheckHash = /*clone*/ $parent->loopCheckHash;
1401                 if ( $pdbk !== false ) {
1402                         $this->loopCheckHash[$pdbk] = true;
1403                 }
1404                 $this->depth = $parent->depth + 1;
1405                 $this->numberedExpansionCache = $this->namedExpansionCache = array();
1406         }
1407
1408         function __toString() {
1409                 $s = 'tplframe{';
1410                 $first = true;
1411                 $args = $this->numberedArgs + $this->namedArgs;
1412                 foreach ( $args as $name => $value ) {
1413                         if ( $first ) {
1414                                 $first = false;
1415                         } else {
1416                                 $s .= ', ';
1417                         }
1418                         $s .= "\"$name\":\"" .
1419                                 str_replace( '"', '\\"', $value->ownerDocument->saveXML( $value ) ) . '"';
1420                 }
1421                 $s .= '}';
1422                 return $s;
1423         }
1424
1425         /**
1426          * Returns true if there are no arguments in this frame
1427          *
1428          * @return bool
1429          */
1430         function isEmpty() {
1431                 return !count( $this->numberedArgs ) && !count( $this->namedArgs );
1432         }
1433
1434         function getArguments() {
1435                 $arguments = array();
1436                 foreach ( array_merge(
1437                                 array_keys($this->numberedArgs),
1438                                 array_keys($this->namedArgs)) as $key ) {
1439                         $arguments[$key] = $this->getArgument($key);
1440                 }
1441                 return $arguments;
1442         }
1443
1444         function getNumberedArguments() {
1445                 $arguments = array();
1446                 foreach ( array_keys($this->numberedArgs) as $key ) {
1447                         $arguments[$key] = $this->getArgument($key);
1448                 }
1449                 return $arguments;
1450         }
1451
1452         function getNamedArguments() {
1453                 $arguments = array();
1454                 foreach ( array_keys($this->namedArgs) as $key ) {
1455                         $arguments[$key] = $this->getArgument($key);
1456                 }
1457                 return $arguments;
1458         }
1459
1460         function getNumberedArgument( $index ) {
1461                 if ( !isset( $this->numberedArgs[$index] ) ) {
1462                         return false;
1463                 }
1464                 if ( !isset( $this->numberedExpansionCache[$index] ) ) {
1465                         # No trimming for unnamed arguments
1466                         $this->numberedExpansionCache[$index] = $this->parent->expand( $this->numberedArgs[$index], PPFrame::STRIP_COMMENTS );
1467                 }
1468                 return $this->numberedExpansionCache[$index];
1469         }
1470
1471         function getNamedArgument( $name ) {
1472                 if ( !isset( $this->namedArgs[$name] ) ) {
1473                         return false;
1474                 }
1475                 if ( !isset( $this->namedExpansionCache[$name] ) ) {
1476                         # Trim named arguments post-expand, for backwards compatibility
1477                         $this->namedExpansionCache[$name] = trim(
1478                                 $this->parent->expand( $this->namedArgs[$name], PPFrame::STRIP_COMMENTS ) );
1479                 }
1480                 return $this->namedExpansionCache[$name];
1481         }
1482
1483         function getArgument( $name ) {
1484                 $text = $this->getNumberedArgument( $name );
1485                 if ( $text === false ) {
1486                         $text = $this->getNamedArgument( $name );
1487                 }
1488                 return $text;
1489         }
1490
1491         /**
1492          * Return true if the frame is a template frame
1493          *
1494          * @return bool
1495          */
1496         function isTemplate() {
1497                 return true;
1498         }
1499 }
1500
1501 /**
1502  * Expansion frame with custom arguments
1503  * @ingroup Parser
1504  */
1505 class PPCustomFrame_DOM extends PPFrame_DOM {
1506         var $args;
1507
1508         function __construct( $preprocessor, $args ) {
1509                 parent::__construct( $preprocessor );
1510                 $this->args = $args;
1511         }
1512
1513         function __toString() {
1514                 $s = 'cstmframe{';
1515                 $first = true;
1516                 foreach ( $this->args as $name => $value ) {
1517                         if ( $first ) {
1518                                 $first = false;
1519                         } else {
1520                                 $s .= ', ';
1521                         }
1522                         $s .= "\"$name\":\"" .
1523                                 str_replace( '"', '\\"', $value->__toString() ) . '"';
1524                 }
1525                 $s .= '}';
1526                 return $s;
1527         }
1528
1529         /**
1530          * @return bool
1531          */
1532         function isEmpty() {
1533                 return !count( $this->args );
1534         }
1535
1536         function getArgument( $index ) {
1537                 if ( !isset( $this->args[$index] ) ) {
1538                         return false;
1539                 }
1540                 return $this->args[$index];
1541         }
1542 }
1543
1544 /**
1545  * @ingroup Parser
1546  */
1547 class PPNode_DOM implements PPNode {
1548
1549         /**
1550          * @var DOMElement
1551          */
1552         var $node;
1553         var $xpath;
1554
1555         function __construct( $node, $xpath = false ) {
1556                 $this->node = $node;
1557         }
1558
1559         /**
1560          * @return DOMXPath
1561          */
1562         function getXPath() {
1563                 if ( $this->xpath === null ) {
1564                         $this->xpath = new DOMXPath( $this->node->ownerDocument );
1565                 }
1566                 return $this->xpath;
1567         }
1568
1569         function __toString() {
1570                 if ( $this->node instanceof DOMNodeList ) {
1571                         $s = '';
1572                         foreach ( $this->node as $node ) {
1573                                 $s .= $node->ownerDocument->saveXML( $node );
1574                         }
1575                 } else {
1576                         $s = $this->node->ownerDocument->saveXML( $this->node );
1577                 }
1578                 return $s;
1579         }
1580
1581         /**
1582          * @return bool|PPNode_DOM
1583          */
1584         function getChildren() {
1585                 return $this->node->childNodes ? new self( $this->node->childNodes ) : false;
1586         }
1587
1588         /**
1589          * @return bool|PPNode_DOM
1590          */
1591         function getFirstChild() {
1592                 return $this->node->firstChild ? new self( $this->node->firstChild ) : false;
1593         }
1594
1595         /**
1596          * @return bool|PPNode_DOM
1597          */
1598         function getNextSibling() {
1599                 return $this->node->nextSibling ? new self( $this->node->nextSibling ) : false;
1600         }
1601
1602         /**
1603          * @param $type
1604          *
1605          * @return bool|PPNode_DOM
1606          */
1607         function getChildrenOfType( $type ) {
1608                 return new self( $this->getXPath()->query( $type, $this->node ) );
1609         }
1610
1611         /**
1612          * @return int
1613          */
1614         function getLength() {
1615                 if ( $this->node instanceof DOMNodeList ) {
1616                         return $this->node->length;
1617                 } else {
1618                         return false;
1619                 }
1620         }
1621
1622         /**
1623          * @param $i
1624          * @return bool|PPNode_DOM
1625          */
1626         function item( $i ) {
1627                 $item = $this->node->item( $i );
1628                 return $item ? new self( $item ) : false;
1629         }
1630
1631         /**
1632          * @return string
1633          */
1634         function getName() {
1635                 if ( $this->node instanceof DOMNodeList ) {
1636                         return '#nodelist';
1637                 } else {
1638                         return $this->node->nodeName;
1639                 }
1640         }
1641
1642         /**
1643          * Split a <part> node into an associative array containing:
1644          *    name          PPNode name
1645          *    index         String index
1646          *    value         PPNode value
1647          *
1648          * @return array
1649          */
1650         function splitArg() {
1651                 $xpath = $this->getXPath();
1652                 $names = $xpath->query( 'name', $this->node );
1653                 $values = $xpath->query( 'value', $this->node );
1654                 if ( !$names->length || !$values->length ) {
1655                         throw new MWException( 'Invalid brace node passed to ' . __METHOD__ );
1656                 }
1657                 $name = $names->item( 0 );
1658                 $index = $name->getAttribute( 'index' );
1659                 return array(
1660                         'name' => new self( $name ),
1661                         'index' => $index,
1662                         'value' => new self( $values->item( 0 ) ) );
1663         }
1664
1665         /**
1666          * Split an <ext> node into an associative array containing name, attr, inner and close
1667          * All values in the resulting array are PPNodes. Inner and close are optional.
1668          *
1669          * @return array
1670          */
1671         function splitExt() {
1672                 $xpath = $this->getXPath();
1673                 $names = $xpath->query( 'name', $this->node );
1674                 $attrs = $xpath->query( 'attr', $this->node );
1675                 $inners = $xpath->query( 'inner', $this->node );
1676                 $closes = $xpath->query( 'close', $this->node );
1677                 if ( !$names->length || !$attrs->length ) {
1678                         throw new MWException( 'Invalid ext node passed to ' . __METHOD__ );
1679                 }
1680                 $parts = array(
1681                         'name' => new self( $names->item( 0 ) ),
1682                         'attr' => new self( $attrs->item( 0 ) ) );
1683                 if ( $inners->length ) {
1684                         $parts['inner'] = new self( $inners->item( 0 ) );
1685                 }
1686                 if ( $closes->length ) {
1687                         $parts['close'] = new self( $closes->item( 0 ) );
1688                 }
1689                 return $parts;
1690         }
1691
1692         /**
1693          * Split a <h> node
1694          */
1695         function splitHeading() {
1696                 if ( $this->getName() !== 'h' ) {
1697                         throw new MWException( 'Invalid h node passed to ' . __METHOD__ );
1698                 }
1699                 return array(
1700                         'i' => $this->node->getAttribute( 'i' ),
1701                         'level' => $this->node->getAttribute( 'level' ),
1702                         'contents' => $this->getChildren()
1703                 );
1704         }
1705 }