some important stuff we'll need

1 files changed, 345 insertions, 0 deletions

diff --git a/lib/htmlpurifier/library/HTMLPurifier/Injector/AutoParagraph.php b/lib/htmlpurifier/library/HTMLPurifier/Injector/AutoParagraph.php
new file mode 100644
index 000000000..afa760892
--- /dev/null
+++ b/lib/htmlpurifier/library/HTMLPurifier/Injector/AutoParagraph.php
@@ -0,0 +1,345 @@
+<?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
+{
+
+    public $name = 'AutoParagraph';
+    public $needed = array('p');
+
+    private function _pStart() {
+        $par = new HTMLPurifier_Token_Start('p');
+        $par->armor['MakeWellFormed_TagClosedError'] = true;
+        return $par;
+    }
+
+    public function handleText(&$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, $token);
+        // Abort!
+        } else {
+            // State 4.1: ...<b>PAR1
+            //                  ----
+
+            // State 4.2: ...<b>PAR1\n\nPAR2
+            //                  ------------
+        }
+    }
+
+    public function handleElement(&$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 $data String text data that will be processed
+     *    into paragraphs
+     * @param $result Reference to array of tokens that the
+     *    tags will be appended onto
+     * @param $config Instance of HTMLPurifier_Config
+     * @param $context Instance of HTMLPurifier_Context
+     */
+    private function _splitText($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($result); // removes </p>
+        }
+
+    }
+
+    /**
+     * Returns true if passed token is inline (and, ergo, allowed in
+     * paragraph tags)
+     */
+    private function _isInline($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.
+     */
+    private function _pLookAhead() {
+        $this->current($i, $current);
+        if ($current instanceof HTMLPurifier_Token_Start) $nesting = 1;
+        else $nesting = 0;
+        $ok = false;
+        while ($this->forwardUntilEndToken($i, $current, $nesting)) {
+            $result = $this->_checkNeedsP($current);
+            if ($result !== null) {
+                $ok = $result;
+                break;
+            }
+        }
+        return $ok;
+    }
+
+    /**
+     * Determines if a particular token requires an earlier inline token
+     * to get a paragraph. This should be used with _forwardUntilEndToken
+     */
+    private function _checkNeedsP($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;
+    }
+
+}
+
+// vim: et sw=4 sts=4