File indexing completed on 2024-05-12 06:02:05

 <?php
 
 /**
  * Injector that auto paragraphs text in the root node based on
  * double-spacing.
  * @todo Ensure all states are unit tested, including variations as well.
  * @todo Make a graph of the flow control for this Injector.
  */
 class HTMLPurifier_Injector_AutoParagraph extends HTMLPurifier_Injector
 {
     /**
      * @type string
      */
     public $name = 'AutoParagraph';
 
     /**
      * @type array
      */
     public $needed = array('p');
 
     /**
      * @return HTMLPurifier_Token_Start
      */
     private function _pStart()
     {
         $par = new HTMLPurifier_Token_Start('p');
         $par->armor['MakeWellFormed_TagClosedError'] = true;
         return $par;
     }
 
     /**
      * @param HTMLPurifier_Token_Text $token
      */
     public function handleText(&$token)
     {
         $text = $token->data;
         // Does the current parent allow <p> tags?
         if ($this->allowsElement('p')) {
             if (empty($this->currentNesting) || strpos($text, "\n\n") !== false) {
                 // Note that we have differing behavior when dealing with text
                 // in the anonymous root node, or a node inside the document.
                 // If the text as a double-newline, the treatment is the same;
                 // if it doesn't, see the next if-block if you're in the document.
 
                 $i = $nesting = null;
                 if (!$this->forwardUntilEndToken($i, $current, $nesting) && $token->is_whitespace) {
                     // State 1.1: ...    ^ (whitespace, then document end)
                     //               ----
                     // This is a degenerate case
                 } else {
                     if (!$token->is_whitespace || $this->_isInline($current)) {
                         // State 1.2: PAR1
                         //            ----
 
                         // State 1.3: PAR1\n\nPAR2
                         //            ------------
 
                         // State 1.4: <div>PAR1\n\nPAR2 (see State 2)
                         //                 ------------
                         $token = array($this->_pStart());
                         $this->_splitText($text, $token);
                     } else {
                         // State 1.5: \n<hr />
                         //            --
                     }
                 }
             } else {
                 // State 2:   <div>PAR1... (similar to 1.4)
                 //                 ----
 
                 // We're in an element that allows paragraph tags, but we're not
                 // sure if we're going to need them.
                 if ($this->_pLookAhead()) {
                     // State 2.1: <div>PAR1<b>PAR1\n\nPAR2
                     //                 ----
                     // Note: This will always be the first child, since any
                     // previous inline element would have triggered this very
                     // same routine, and found the double newline. One possible
                     // exception would be a comment.
                     $token = array($this->_pStart(), $token);
                 } else {
                     // State 2.2.1: <div>PAR1<div>
                     //                   ----
 
                     // State 2.2.2: <div>PAR1<b>PAR1</b></div>
                     //                   ----
                 }
             }
             // Is the current parent a <p> tag?
         } elseif (!empty($this->currentNesting) &&
             $this->currentNesting[count($this->currentNesting) - 1]->name == 'p') {
             // State 3.1: ...<p>PAR1
             //                  ----
 
             // State 3.2: ...<p>PAR1\n\nPAR2
             //                  ------------
             $token = array();
             $this->_splitText($text, $token);
             // Abort!
         } else {
             // State 4.1: ...<b>PAR1
             //                  ----
 
             // State 4.2: ...<b>PAR1\n\nPAR2
             //                  ------------
         }
     }
 
     /**
      * @param HTMLPurifier_Token $token
      */
     public function handleElement(&$token)
     {
         // We don't have to check if we're already in a <p> tag for block
         // tokens, because the tag would have been autoclosed by MakeWellFormed.
         if ($this->allowsElement('p')) {
             if (!empty($this->currentNesting)) {
                 if ($this->_isInline($token)) {
                     // State 1: <div>...<b>
                     //                  ---
                     // Check if this token is adjacent to the parent token
                     // (seek backwards until token isn't whitespace)
                     $i = null;
                     $this->backward($i, $prev);
 
                     if (!$prev instanceof HTMLPurifier_Token_Start) {
                         // Token wasn't adjacent
                         if ($prev instanceof HTMLPurifier_Token_Text &&
                             substr($prev->data, -2) === "\n\n"
                         ) {
                             // State 1.1.4: <div><p>PAR1</p>\n\n<b>
                             //                                  ---
                             // Quite frankly, this should be handled by splitText
                             $token = array($this->_pStart(), $token);
                         } else {
                             // State 1.1.1: <div><p>PAR1</p><b>
                             //                              ---
                             // State 1.1.2: <div><br /><b>
                             //                         ---
                             // State 1.1.3: <div>PAR<b>
                             //                      ---
                         }
                     } else {
                         // State 1.2.1: <div><b>
                         //                   ---
                         // Lookahead to see if <p> is needed.
                         if ($this->_pLookAhead()) {
                             // State 1.3.1: <div><b>PAR1\n\nPAR2
                             //                   ---
                             $token = array($this->_pStart(), $token);
                         } else {
                             // State 1.3.2: <div><b>PAR1</b></div>
                             //                   ---
 
                             // State 1.3.3: <div><b>PAR1</b><div></div>\n\n</div>
                             //                   ---
                         }
                     }
                 } else {
                     // State 2.3: ...<div>
                     //               -----
                 }
             } else {
                 if ($this->_isInline($token)) {
                     // State 3.1: <b>
                     //            ---
                     // This is where the {p} tag is inserted, not reflected in
                     // inputTokens yet, however.
                     $token = array($this->_pStart(), $token);
                 } else {
                     // State 3.2: <div>
                     //            -----
                 }
 
                 $i = null;
                 if ($this->backward($i, $prev)) {
                     if (!$prev instanceof HTMLPurifier_Token_Text) {
                         // State 3.1.1: ...</p>{p}<b>
                         //                        ---
                         // State 3.2.1: ...</p><div>
                         //                     -----
                         if (!is_array($token)) {
                             $token = array($token);
                         }
                         array_unshift($token, new HTMLPurifier_Token_Text("\n\n"));
                     } else {
                         // State 3.1.2: ...</p>\n\n{p}<b>
                         //                            ---
                         // State 3.2.2: ...</p>\n\n<div>
                         //                         -----
                         // Note: PAR<ELEM> cannot occur because PAR would have been
                         // wrapped in <p> tags.
                     }
                 }
             }
         } else {
             // State 2.2: <ul><li>
             //                ----
             // State 2.4: <p><b>
             //               ---
         }
     }
 
     /**
      * Splits up a text in paragraph tokens and appends them
      * to the result stream that will replace the original
      * @param string $data String text data that will be processed
      *    into paragraphs
      * @param HTMLPurifier_Token[] $result Reference to array of tokens that the
      *    tags will be appended onto
      */
     private function _splitText($data, &$result)
     {
         $raw_paragraphs = explode("\n\n", $data);
         $paragraphs = array(); // without empty paragraphs
         $needs_start = false;
         $needs_end = false;
 
         $c = count($raw_paragraphs);
         if ($c == 1) {
             // There were no double-newlines, abort quickly. In theory this
             // should never happen.
             $result[] = new HTMLPurifier_Token_Text($data);
             return;
         }
         for ($i = 0; $i < $c; $i++) {
             $par = $raw_paragraphs[$i];
             if (trim($par) !== '') {
                 $paragraphs[] = $par;
             } else {
                 if ($i == 0) {
                     // Double newline at the front
                     if (empty($result)) {
                         // The empty result indicates that the AutoParagraph
                         // injector did not add any start paragraph tokens.
                         // This means that we have been in a paragraph for
                         // a while, and the newline means we should start a new one.
                         $result[] = new HTMLPurifier_Token_End('p');
                         $result[] = new HTMLPurifier_Token_Text("\n\n");
                         // However, the start token should only be added if
                         // there is more processing to be done (i.e. there are
                         // real paragraphs in here). If there are none, the
                         // next start paragraph tag will be handled by the
                         // next call to the injector
                         $needs_start = true;
                     } else {
                         // We just started a new paragraph!
                         // Reinstate a double-newline for presentation's sake, since
                         // it was in the source code.
                         array_unshift($result, new HTMLPurifier_Token_Text("\n\n"));
                     }
                 } elseif ($i + 1 == $c) {
                     // Double newline at the end
                     // There should be a trailing </p> when we're finally done.
                     $needs_end = true;
                 }
             }
         }
 
         // Check if this was just a giant blob of whitespace. Move this earlier,
         // perhaps?
         if (empty($paragraphs)) {
             return;
         }
 
         // Add the start tag indicated by \n\n at the beginning of $data
         if ($needs_start) {
             $result[] = $this->_pStart();
         }
 
         // Append the paragraphs onto the result
         foreach ($paragraphs as $par) {
             $result[] = new HTMLPurifier_Token_Text($par);
             $result[] = new HTMLPurifier_Token_End('p');
             $result[] = new HTMLPurifier_Token_Text("\n\n");
             $result[] = $this->_pStart();
         }
 
         // Remove trailing start token; Injector will handle this later if
         // it was indeed needed. This prevents from needing to do a lookahead,
         // at the cost of a lookbehind later.
         array_pop($result);
 
         // If there is no need for an end tag, remove all of it and let
         // MakeWellFormed close it later.
         if (!$needs_end) {
             array_pop($result); // removes \n\n
             array_pop($result); // removes </p>
         }
     }
 
     /**
      * Returns true if passed token is inline (and, ergo, allowed in
      * paragraph tags)
      * @param HTMLPurifier_Token $token
      * @return bool
      */
     private function _isInline($token)
     {
         return isset($this->htmlDefinition->info['p']->child->elements[$token->name]);
     }
 
     /**
      * Looks ahead in the token list and determines whether or not we need
      * to insert a <p> tag.
      * @return bool
      */
     private function _pLookAhead()
     {
         if ($this->currentToken instanceof HTMLPurifier_Token_Start) {
             $nesting = 1;
         } else {
             $nesting = 0;
         }
         $ok = false;
         $i = null;
         while ($this->forwardUntilEndToken($i, $current, $nesting)) {
             $result = $this->_checkNeedsP($current);
             if ($result !== null) {
                 $ok = $result;
                 break;
             }
         }
         return $ok;
     }
 
     /**
      * Determines if a particular token requires an earlier inline token
      * to get a paragraph. This should be used with _forwardUntilEndToken
      * @param HTMLPurifier_Token $current
      * @return bool
      */
     private function _checkNeedsP($current)
     {
         if ($current instanceof HTMLPurifier_Token_Start) {
             if (!$this->_isInline($current)) {
                 // <div>PAR1<div>
                 //      ----
                 // Terminate early, since we hit a block element
                 return false;
             }
         } elseif ($current instanceof HTMLPurifier_Token_Text) {
             if (strpos($current->data, "\n\n") !== false) {
                 // <div>PAR1<b>PAR1\n\nPAR2
                 //      ----
                 return true;
             } else {
                 // <div>PAR1<b>PAR1...
                 //      ----
             }
         }
         return null;
     }
 }
 
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