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