mediawiki-extensions-Discus.../includes/CommentParser.php
Bartosz Dziewoński 9ee0fd69f5 Allow headings to have IDs
Previously, only comments could have IDs, because we only needed IDs
for replying. But we might also use them for notifications soon.

Bug: T264478
Change-Id: I1bcad02bf17ab54bc5028a959543c10f0430836b
2020-10-22 02:04:28 +02:00

1083 lines
34 KiB
PHP

<?php
namespace MediaWiki\Extension\DiscussionTools;
use Config;
use DateInterval;
use DateTime;
use DateTimeImmutable;
use DateTimeZone;
use DOMElement;
use DOMNode;
use DOMText;
use IP;
use Language;
use MediaWiki\MediaWikiServices;
use MWException;
use Title;
// TODO clean up static vs non-static
// TODO consider making timestamp parsing not a returned function
class CommentParser {
private const SIGNATURE_SCAN_LIMIT = 100;
/** @var DOMElement */
private $rootNode;
/** @var ThreadItem[] */
private $threadItems;
/** @var CommentItem[] */
private $commentItems;
/** @var ThreadItem[] */
private $threadItemsById;
/** @var HeadingItem[] */
private $threads;
/** @var Config */
private $config;
/** @var Language */
private $language;
private $dateFormat;
private $digits;
/** @var string[][] */
private $contLangMessages;
private $localTimezone;
private $timezones;
/**
* @param DomElement $rootNode Root node of content to parse
* @param Language $language Content language
* @param Config $config
* @param array $data
*/
public function __construct( DOMElement $rootNode, Language $language, Config $config, array $data = [] ) {
$this->rootNode = $rootNode;
$this->config = $config;
$this->language = $language;
if ( !$data ) {
// TODO: Instead of passing data used for mocking, mock the methods that fetch the data.
$data = Data::getLocalData( null, $config, $language );
}
$this->dateFormat = $data['dateFormat'];
$this->digits = $data['digits'];
$this->contLangMessages = $data['contLangMessages'];
$this->localTimezone = $data['localTimezone'];
$this->timezones = $data['timezones'];
}
/**
* @param DomElement $rootNode Root node
* @return CommentParser
*/
public static function newFromGlobalState( DOMElement $rootNode ) : CommentParser {
return new static(
$rootNode,
MediaWikiServices::getInstance()->getContentLanguage(),
MediaWikiServices::getInstance()->getMainConfig()
);
}
/**
* Return the next leaf node in the tree order that is likely a part of a discussion comment,
* rather than some boring "separator" element.
*
* Currently, this can return a Text node with content other than whitespace, or an `<img>` node.
*
* @param DOMNode $node Node to start searching at. This node's children are ignored.
* @return DOMNode
*/
private function nextInterestingLeafNode( DOMNode $node ) : DOMNode {
$rootNode = $this->rootNode;
$treeWalker = new TreeWalker(
$rootNode,
NodeFilter::SHOW_ELEMENT | NodeFilter::SHOW_TEXT,
function ( $n ) use ( $node, $rootNode ) {
// Ignore this node and its descendants
// (unless it's the root node, this is a special case for "fakeHeading" handling)
if ( $node !== $rootNode && ( $n === $node || $n->parentNode === $node ) ) {
return NodeFilter::FILTER_REJECT;
}
if (
(
$n->nodeType === XML_TEXT_NODE &&
CommentUtils::htmlTrim( $n->nodeValue ) !== ''
) ||
(
$n->nodeType === XML_CDATA_SECTION_NODE &&
CommentUtils::htmlTrim( $n->nodeValue ) !== ''
) ||
(
$n->nodeType === XML_ELEMENT_NODE &&
strtolower( $n->nodeName ) === 'img'
)
) {
return NodeFilter::FILTER_ACCEPT;
}
return NodeFilter::FILTER_SKIP;
}
);
$treeWalker->currentNode = $node;
$treeWalker->nextNode();
if ( !$treeWalker->currentNode ) {
throw new MWException( 'nextInterestingLeafNode not found' );
}
return $treeWalker->currentNode;
}
/**
* @param string[] $values Values to match
* @return string Regular expression
*/
private static function regexpAlternateGroup( array $values ) : string {
return '(' . implode( '|', array_map( function ( string $x ) {
return preg_quote( $x, '/' );
}, $values ) ) . ')';
}
/**
* Get text of localisation messages in content language.
*
* @param string $contLangVariant Content language variant
* @param string[] $messages Message keys
* @return string[] Message values
*/
private function getMessages( string $contLangVariant, array $messages ) : array {
return array_map( function ( string $key ) use ( $contLangVariant ) {
return $this->contLangMessages[$contLangVariant][$key];
}, $messages );
}
/**
* Get a regexp that matches timestamps generated using the given date format.
*
* This only supports format characters that are used by the default date format in any of
* MediaWiki's languages, namely: D, d, F, G, H, i, j, l, M, n, Y, xg, xkY (and escape characters),
* and only dates when MediaWiki existed, let's say 2000 onwards (Thai dates before 1941 are
* complicated).
*
* @param string $contLangVariant Content language variant
* @param string $format Date format
* @param string $digitsRegexp Regular expression matching a single localised digit, e.g. '[0-9]'
* @param array $tzAbbrs Associative array mapping localised timezone abbreviations to
* IANA abbreviations, for the local timezone, e.g. [ 'EDT' => 'EDT', 'EST' => 'EST' ]
* @return string Regular expression
*/
private function getTimestampRegexp(
string $contLangVariant, string $format, string $digitsRegexp, array $tzAbbrs
) : string {
$formatLength = strlen( $format );
$s = '';
// Adapted from Language::sprintfDate()
for ( $p = 0; $p < $formatLength; $p++ ) {
$num = false;
$code = $format[ $p ];
if ( $code === 'x' && $p < $formatLength - 1 ) {
$code .= $format[++$p];
}
if ( $code === 'xk' && $p < $formatLength - 1 ) {
$code .= $format[++$p];
}
switch ( $code ) {
case 'xx' :
$s .= 'x';
break;
case 'xg':
$s .= self::regexpAlternateGroup(
$this->getMessages( $contLangVariant, Language::MONTH_GENITIVE_MESSAGES )
);
break;
case 'd':
$num = '2';
break;
case 'D':
$s .= self::regexpAlternateGroup(
$this->getMessages( $contLangVariant, Language::WEEKDAY_ABBREVIATED_MESSAGES )
);
break;
case 'j':
$num = '1,2';
break;
case 'l':
$s .= self::regexpAlternateGroup(
$this->getMessages( $contLangVariant, Language::WEEKDAY_MESSAGES )
);
break;
case 'F':
$s .= self::regexpAlternateGroup(
$this->getMessages( $contLangVariant, Language::MONTH_MESSAGES )
);
break;
case 'M':
$s .= self::regexpAlternateGroup(
$this->getMessages( $contLangVariant, Language::MONTH_ABBREVIATED_MESSAGES )
);
break;
case 'n':
$num = '1,2';
break;
case 'Y':
$num = '4';
break;
case 'xkY':
$num = '4';
break;
case 'G':
$num = '1,2';
break;
case 'H':
$num = '2';
break;
case 'i':
$num = '2';
break;
case '\\':
// Backslash escaping
if ( $p < $formatLength - 1 ) {
$s .= preg_quote( $format[++$p], '/' );
} else {
$s .= preg_quote( '\\', '/' );
}
break;
case '"':
// Quoted literal
if ( $p < $formatLength - 1 ) {
$endQuote = strpos( $format, '"', $p + 1 );
if ( $endQuote === false ) {
// No terminating quote, assume literal "
$s .= '"';
} else {
$s .= preg_quote( substr( $format, $p + 1, $endQuote - $p - 1 ), '/' );
$p = $endQuote;
}
} else {
// Quote at end of string, assume literal "
$s .= '"';
}
break;
default:
$s .= preg_quote( $format[$p], '/' );
}
if ( $num !== false ) {
$s .= '(' . $digitsRegexp . '{' . $num . '})';
}
}
$tzRegexp = self::regexpAlternateGroup( array_keys( $tzAbbrs ) );
// Hard-coded parentheses and space like in Parser::pstPass2
// Ignore some invisible Unicode characters that often sneak into copy-pasted timestamps (T245784)
// \uNNNN syntax can only be used from PHP 7.3
return '/' . $s . '[\\x{200E}\\x{200F}]? [\\x{200E}\\x{200F}]?\\(' . $tzRegexp . '\\)/u';
}
/**
* Get a function that parses timestamps generated using the given date format, based on the result
* of matching the regexp returned by getTimestampRegexp()
*
* @param string $contLangVariant Content language variant
* @param string $format Date format, as used by MediaWiki
* @param string[]|null $digits Localised digits from 0 to 9, e.g. `[ '0', '1', ..., '9' ]`
* @param string $localTimezone Local timezone IANA name, e.g. `America/New_York`
* @param array $tzAbbrs Map of localised timezone abbreviations to IANA abbreviations
* for the local timezone, e.g. [ 'EDT' => 'EDT', 'EST' => 'EST' ]
* @return callable Parser function
*/
private function getTimestampParser(
string $contLangVariant, string $format, ?array $digits, string $localTimezone, array $tzAbbrs
) : callable {
$untransformDigits = function ( string $text ) use ( $digits ) {
if ( !$digits ) {
return $text;
}
return preg_replace_callback(
'/[' . implode( '', $digits ) . ']/u',
function ( array $m ) use ( $digits ) {
return (string)array_search( $m[0], $digits );
},
$text
);
};
$formatLength = strlen( $format );
$matchingGroups = [];
for ( $p = 0; $p < $formatLength; $p++ ) {
$code = $format[$p];
if ( $code === 'x' && $p < $formatLength - 1 ) {
$code .= $format[++$p];
}
if ( $code === 'xk' && $p < $formatLength - 1 ) {
$code .= $format[++$p];
}
switch ( $code ) {
case 'xx':
break;
case 'xg':
case 'd':
case 'j':
case 'D':
case 'l':
case 'F':
case 'M':
case 'n':
case 'Y':
case 'xkY':
case 'G':
case 'H':
case 'i':
$matchingGroups[] = $code;
break;
case '\\':
// Backslash escaping
if ( $p < $formatLength - 1 ) {
$p++;
}
break;
case '"':
// Quoted literal
if ( $p < $formatLength - 1 ) {
$endQuote = strpos( $format, '"', $p + 1 );
if ( $endQuote !== false ) {
$p = $endQuote;
}
}
break;
default:
break;
}
}
return function ( array $match ) use (
$matchingGroups, $untransformDigits, $localTimezone, $tzAbbrs, $contLangVariant
) {
if ( is_array( $match[0] ) ) {
// Strip PREG_OFFSET_CAPTURE data
unset( $match['offset'] );
$match = array_map( function ( array $tuple ) {
return $tuple[0];
}, $match );
}
$year = 0;
$monthIdx = 0;
$day = 0;
$hour = 0;
$minute = 0;
foreach ( $matchingGroups as $i => $code ) {
$text = $match[$i + 1];
switch ( $code ) {
case 'xg':
$monthIdx = array_search(
$text,
$this->getMessages( $contLangVariant, Language::MONTH_GENITIVE_MESSAGES )
);
break;
case 'd':
case 'j':
$day = intval( $untransformDigits( $text ) );
break;
case 'D':
case 'l':
// Day of the week - unused
break;
case 'F':
$monthIdx = array_search(
$text,
$this->getMessages( $contLangVariant, Language::MONTH_MESSAGES )
);
break;
case 'M':
$monthIdx = array_search(
$text,
$this->getMessages( $contLangVariant, Language::MONTH_ABBREVIATED_MESSAGES )
);
break;
case 'n':
$monthIdx = intval( $untransformDigits( $text ) ) - 1;
break;
case 'Y':
$year = intval( $untransformDigits( $text ) );
break;
case 'xkY':
// Thai year
$year = intval( $untransformDigits( $text ) ) - 543;
break;
case 'G':
case 'H':
$hour = intval( $untransformDigits( $text ) );
break;
case 'i':
$minute = intval( $untransformDigits( $text ) );
break;
default:
// TODO throw NotImplementedException or whatever it's called
throw new MWException( 'Not implemented' );
}
}
// The last matching group is the timezone abbreviation
$tzAbbr = $tzAbbrs[ end( $match ) ];
// Most of the time, the timezone abbreviation is not necessary to parse the date, since we
// can assume all times are in the wiki's local timezone.
$date = new DateTime();
// setTimezone must be called before setDate/setTime
$date->setTimezone( new DateTimeZone( $localTimezone ) );
$date->setDate( $year, $monthIdx + 1, $day );
$date->setTime( $hour, $minute, 0 );
// But during the "fall back" at the end of DST, some times will happen twice.
// Since the timezone abbreviation disambiguates the DST/non-DST times, we can detect
// when PHP chose the wrong one, and then try the other one. It appears that PHP always
// uses the later (non-DST) hour, but that behavior isn't documented, so we account for both.
if ( $date->format( 'T' ) !== $tzAbbr ) {
$altDate = clone $date;
if ( $date->format( 'I' ) ) {
// Parsed time is DST, try non-DST by advancing one hour
$altDate->add( new DateInterval( 'PT1H' ) );
} else {
// Parsed time is non-DST, try DST by going back one hour
$altDate->sub( new DateInterval( 'PT1H' ) );
}
if ( $altDate->format( 'T' ) === $tzAbbr ) {
$date = $altDate;
$discussionToolsWarning = 'Timestamp has timezone abbreviation for the wrong time';
} else {
$discussionToolsWarning = 'Ambiguous time at DST switchover was parsed';
}
}
// Now set the timezone back to UTC for formatting
$date->setTimezone( new DateTimeZone( 'UTC' ) );
$date = DateTimeImmutable::createFromMutable( $date );
if ( isset( $discussionToolsWarning ) ) {
// @phan-suppress-next-line PhanUndeclaredProperty
$date->discussionToolsWarning = $discussionToolsWarning;
}
return $date;
};
}
/**
* Get a regexp that matches timestamps in the local date format, for each language variant.
*
* This calls getTimestampRegexp() with predefined data for the current wiki.
*
* @return string[] Regular expressions
*/
public function getLocalTimestampRegexps() : array {
return array_map( function ( $contLangVariant ) {
return $this->getTimestampRegexp(
$contLangVariant,
$this->dateFormat[$contLangVariant],
'[' . implode( '', $this->digits[$contLangVariant] ) . ']',
$this->timezones[$contLangVariant]
);
}, $this->language->getVariants() );
}
/**
* Get a function that parses timestamps in the local date format, for each language variant,
* based on the result of matching the regexp returned by getLocalTimestampRegexp().
*
* This calls getTimestampParser() with predefined data for the current wiki.
*
* @return callable[] Parser functions
*/
private function getLocalTimestampParsers() : array {
return array_map( function ( $contLangVariant ) {
return $this->getTimestampParser(
$contLangVariant,
$this->dateFormat[$contLangVariant],
$this->digits[$contLangVariant],
$this->localTimezone,
$this->timezones[$contLangVariant]
);
}, $this->language->getVariants() );
}
/**
* Find a user signature preceding a timestamp.
*
* The signature includes the timestamp node.
*
* A signature must contain at least one link to the user's userpage, discussion page or
* contributions (and may contain other links). The link may be nested in other elements.
*
* This function returns a two-element array. The first element is an array of sibling nodes
* comprising the signature, in reverse order (with $timestampNode or its parent node as the last
* element). The second element is the username (null for unsigned comments).
*
* @param DOMText $timestampNode Text node
* @param DOMNode|null $until Node to stop searching at
* @return array [ nodes, username ]
*/
private function findSignature( DOMText $timestampNode, ?DOMNode $until = null ) : array {
// Support timestamps being linked to the diff introducing the comment:
// if the timestamp node is the only child of a link node, use the link node instead
if (
!$timestampNode->previousSibling && !$timestampNode->nextSibling &&
strtolower( $timestampNode->parentNode->nodeName ) === 'a'
) {
$timestampNode = $timestampNode->parentNode;
}
$node = $timestampNode;
$sigNodes = [ $node ];
$sigUsername = null;
$length = 0;
$lastLinkNode = $timestampNode;
while (
( $node = $node->previousSibling ) && $length < self::SIGNATURE_SCAN_LIMIT && $node !== $until
) {
$sigNodes[] = $node;
$length += $node->textContent ? mb_strlen( $node->textContent ) : 0;
if ( !( $node instanceof DOMElement ) ) {
continue;
}
$links = [];
if ( strtolower( $node->nodeName ) === 'a' ) {
$links = [ $node ];
} else {
// Handle links nested in formatting elements.
// Helpful accidental feature: users whose signature is not detected in full (due to
// text formatting) can just wrap it in a <span> to fix that.
// "Ten Pound Hammer • (What did I screw up now?)"
// "« Saper // dyskusja »"
$links = iterator_to_array( $node->getElementsByTagName( 'a' ) );
}
if ( !count( $links ) ) {
continue;
}
// Find the closest link before timestamp that links to the user's user page.
foreach ( array_reverse( $links ) as $link ) {
$username = null;
$title = CommentUtils::getTitleFromUrl( $link->getAttribute( 'href' ) );
if ( !$title ) {
continue;
}
if ( $title->getNamespace() === NS_USER || $title->getNamespace() === NS_USER_TALK ) {
$username = $title->getText();
if ( strpos( $username, '/' ) !== false ) {
continue;
}
} elseif ( $title->isSpecial( 'Contributions' ) ) {
$parts = explode( '/', $title->getText(), 2 );
if ( !isset( $parts[1] ) ) {
continue;
}
// Normalize the username: users may link to their contributions with an unnormalized name
$userpage = Title::makeTitleSafe( NS_USER, $parts[1] );
if ( !$userpage ) {
continue;
}
$username = $userpage->getText();
}
if ( !$username ) {
continue;
}
if ( IP::isIPv6( $username ) ) {
// Bot-generated links "Preceding unsigned comment added by" have non-standard case
$username = strtoupper( $username );
}
// Accept the first link to the user namespace, then only accept links to that user
if ( $sigUsername === null ) {
$sigUsername = $username;
}
if ( $username === $sigUsername ) {
$lastLinkNode = $node;
break;
}
}
// Keep looking if a node with links wasn't a link to a user page
// "Doc James (talk · contribs · email)"
}
// Pop excess text nodes
while ( end( $sigNodes ) !== $lastLinkNode ) {
array_pop( $sigNodes );
}
return [ $sigNodes, $sigUsername ];
}
/**
* Callback for TreeWalker that will skip over nodes where we don't want to detect
* comments (or section headings).
*
* @param DOMNode $node
* @return int Appropriate NodeFilter constant
*/
public static function acceptOnlyNodesAllowingComments( DOMNode $node ) {
// The table of contents has a heading that gets erroneously detected as a section
if ( $node instanceof DOMElement && $node->getAttribute( 'id' ) === 'toc' ) {
return NodeFilter::FILTER_REJECT;
}
return NodeFilter::FILTER_ACCEPT;
}
/**
* Find a timestamps in a given text node
*
* @param DOMText $node Text node
* @param string[] $timestampRegexps Timestamp regexps
* @return array|null Array with the following keys:
* - int 'offset' Length of extra text preceding the node that was used for matching
* - int 'parserIndex' Which of the regexps matched
* - array 'matchData' Regexp match data, which specifies the location of the match,
* and which can be parsed using getLocalTimestampParsers()
*/
public function findTimestamp( DOMText $node, array $timestampRegexps ) : ?array {
$nodeText = '';
$offset = 0;
while ( $node ) {
$nodeText = $node->nodeValue . $nodeText;
// In Parsoid HTML, entities are represented as a 'mw:Entity' node, rather than normal HTML
// entities. On Arabic Wikipedia, the "UTC" timezone name contains some non-breaking spaces,
// which apparently are often turned into &nbsp; entities by buggy editing tools. To handle
// this, we must piece together the text, so that our regexp can match those timestamps.
if (
( $previousSibling = $node->previousSibling ) &&
$previousSibling instanceof DOMElement &&
$previousSibling->getAttribute( 'typeof' ) === 'mw:Entity'
) {
$nodeText = $previousSibling->firstChild->nodeValue . $nodeText;
$offset += strlen( $previousSibling->firstChild->nodeValue );
// If the entity is preceded by more text, do this again
if (
$previousSibling->previousSibling &&
$previousSibling->previousSibling instanceof DOMText
) {
$offset += strlen( $previousSibling->previousSibling->nodeValue );
$node = $previousSibling->previousSibling;
} else {
$node = null;
}
} else {
$node = null;
}
}
foreach ( $timestampRegexps as $i => $timestampRegexp ) {
$matchData = null;
// Allows us to mimic match.index in #getComments
if ( preg_match( $timestampRegexp, $nodeText, $matchData, PREG_OFFSET_CAPTURE ) ) {
return [
'matchData' => $matchData,
'offset' => $offset,
'parserIndex' => $i,
];
}
}
return null;
}
/**
* Get all discussion comments (and headings) within a DOM subtree.
*
* This returns a flat list, use getThreads() to get a tree structure starting at section headings.
*
* For example, for a MediaWiki discussion like this (we're dealing with HTML DOM here,
* the wikitext syntax is just for illustration):
*
* == A ==
* B. ~~~~
* : C.
* : C. ~~~~
* :: D. ~~~~
* ::: E. ~~~~
* ::: F. ~~~~
* : G. ~~~~
* H. ~~~~
* : I. ~~~~
*
* This function would return a structure like:
*
* [
* HeadingItem( { level: 0, range: (h2: A) } ),
* CommentItem( { level: 1, range: (p: B) } ),
* CommentItem( { level: 2, range: (li: C, li: C) } ),
* CommentItem( { level: 3, range: (li: D) } ),
* CommentItem( { level: 4, range: (li: E) } ),
* CommentItem( { level: 4, range: (li: F) } ),
* CommentItem( { level: 2, range: (li: G) } ),
* CommentItem( { level: 1, range: (p: H) } ),
* CommentItem( { level: 2, range: (li: I) } )
* ]
*
* @return ThreadItem[] Thread items
*/
public function getThreadItems() : array {
if ( !$this->threadItems ) {
$this->buildThreads();
}
return $this->threadItems;
}
/**
* Same as getFlatThreadItems, but only returns the CommentItems
*
* @return CommentItem[] Comment items
*/
public function getCommentItems() : array {
if ( !$this->commentItems ) {
$this->buildThreads();
}
return $this->commentItems;
}
/**
* Find a ThreadItem by its ID
*
* @param string $id ID
* @return ThreadItem|null Thread item, null if not found
*/
public function findCommentById( string $id ) : ?ThreadItem {
if ( !$this->threadItemsById ) {
$this->buildThreads();
}
return $this->threadItemsById[$id] ?? null;
}
private function buildThreadItems() : void {
$timestampRegexps = $this->getLocalTimestampRegexps();
$commentItems = [];
$threadItems = [];
$dfParsers = $this->getLocalTimestampParsers();
// Placeholder heading in case there are comments in the 0th section
$range = new ImmutableRange( $this->rootNode, 0, $this->rootNode, 0 );
$fakeHeading = new HeadingItem( $range, true );
$fakeHeading->setRootNode( $this->rootNode );
$curComment = $fakeHeading;
$treeWalker = new TreeWalker(
$this->rootNode,
NodeFilter::SHOW_ELEMENT | NodeFilter::SHOW_TEXT,
[ self::class, 'acceptOnlyNodesAllowingComments' ]
);
$lastSigNode = null;
while ( $node = $treeWalker->nextNode() ) {
if ( $node instanceof DOMElement && preg_match( '/^h[1-6]$/i', $node->tagName ) ) {
$range = new ImmutableRange( $node, 0, $node, $node->childNodes->length );
$curComment = new HeadingItem( $range );
$curComment->setRootNode( $this->rootNode );
$threadItems[] = $curComment;
} elseif ( $node instanceof DOMText && ( $match = $this->findTimestamp( $node, $timestampRegexps ) ) ) {
$warnings = [];
$foundSignature = $this->findSignature( $node, $lastSigNode );
$author = $foundSignature[1];
$firstSigNode = end( $foundSignature[0] );
$lastSigNode = $foundSignature[0][0];
if ( !$author ) {
// Ignore timestamps for which we couldn't find a signature. It's probably not a real
// comment, but just a false match due to a copypasted timestamp.
continue;
}
$lastSigNodeOffset = $lastSigNode === $node ?
$match['matchData'][0][1] + strlen( $match['matchData'][0][0] ) - $match['offset'] :
CommentUtils::childIndexOf( $lastSigNode ) + 1;
$sigRange = new ImmutableRange(
$firstSigNode->parentNode,
CommentUtils::childIndexOf( $firstSigNode ),
$lastSigNode === $node ? $node : $lastSigNode->parentNode,
$lastSigNodeOffset
);
// Everything from the last comment up to here is the next comment
$startNode = $this->nextInterestingLeafNode( $curComment->getRange()->endContainer );
$endNode = $lastSigNode;
// Skip to the end of the "paragraph". This only looks at tag names and can be fooled by CSS, but
// avoiding that would be more difficult and slower.
while ( $endNode->nextSibling && !CommentUtils::isBlockElement( $endNode->nextSibling ) ) {
$endNode = $endNode->nextSibling;
}
if ( $endNode === $lastSigNode ) {
$range = new ImmutableRange(
$startNode->parentNode,
CommentUtils::childIndexOf( $startNode ),
$sigRange->endContainer,
$sigRange->endOffset
);
} else {
$length = ( $endNode->nodeType === XML_TEXT_NODE ) ?
strlen( rtrim( $endNode->nodeValue, "\t\n\f\r " ) ) :
// PHP bug: childNodes can be null for comment nodes
// (it should always be a DOMNodeList, even if the node can't have children)
( $endNode->childNodes ? $endNode->childNodes->length : 0 );
$range = new ImmutableRange(
$startNode->parentNode,
CommentUtils::childIndexOf( $startNode ),
$endNode,
$length
);
}
$startLevel = CommentUtils::getIndentLevel( $startNode, $this->rootNode ) + 1;
$endLevel = CommentUtils::getIndentLevel( $node, $this->rootNode ) + 1;
if ( $startLevel !== $endLevel ) {
$warnings[] = 'Comment starts and ends with different indentation';
}
// Should this use the indent level of $startNode or $node?
$level = min( $startLevel, $endLevel );
$dateTime = $dfParsers[ $match['parserIndex'] ]( $match['matchData'] );
if ( isset( $dateTime->discussionToolsWarning ) ) {
$warnings[] = $dateTime->discussionToolsWarning;
}
// ISO 8601 date. Almost DateTimeInterface::RFC3339_EXTENDED, but ending with 'Z' instead
// of '+00:00', like Date#toISOString in JavaScript.
$dateTimeStr = $dateTime->format( 'Y-m-d\TH:i:s.v\Z' );
// Avoid generating multiple comments when there is more than one signature on a single "line".
// Often this is done when someone edits their comment later and wants to add a note about that.
// (Or when another person corrects a typo, or strikes out a comment, etc.) Multiple comments
// within one paragraph/list-item result in a confusing double "Reply" button, and we also have
// no way to indicate which one you're replying to (this might matter in the future for
// notifications or something).
if (
$curComment instanceof CommentItem &&
(
CommentUtils::closestElement(
$node, [ 'li', 'dd', 'p' ]
) ?? $node->parentNode
) ===
(
CommentUtils::closestElement(
$curComment->getRange()->endContainer, [ 'li', 'dd', 'p' ]
) ?? $curComment->getRange()->endContainer->parentNode
)
) {
// Merge this with the previous comment. Use that comment's author and timestamp.
$curComment->addSignatureRange( $sigRange );
if (
$curComment->getRange()->endContainer === $range->endContainer &&
$curComment->getRange()->endOffset <= $range->endOffset
) {
// We've already skipped over this signature, and the $range and $level are messed up,
// because that causes $startNode to be after $endNode
continue;
}
$curComment->setRange(
$curComment->getRange()->setEnd( $range->endContainer, $range->endOffset )
);
$curComment->setLevel( min( $level, $curComment->getLevel() ) );
continue;
}
$curComment = new CommentItem(
$level,
$range,
[ $sigRange ],
$dateTimeStr,
$author
);
$curComment->setRootNode( $this->rootNode );
if ( $warnings ) {
$curComment->addWarnings( $warnings );
}
$commentItems[] = $curComment;
$threadItems[] = $curComment;
}
}
// Insert the fake placeholder heading if there are any comments in the 0th section
// (before the first real heading)
if ( count( $threadItems ) && !( $threadItems[ 0 ] instanceof HeadingItem ) ) {
array_unshift( $threadItems, $fakeHeading );
}
$this->commentItems = $commentItems;
$this->threadItems = $threadItems;
}
/**
* Group discussion comments into threads and associate replies to original messages.
*
* Each thread must begin with a heading. Original messages in the thread are treated as replies to
* its heading. Other replies are associated based on the order and indentation level.
*
* Note that the objects in `comments` are extended in-place with the additional data.
*
* For example, for a MediaWiki discussion like this (we're dealing with HTML DOM here,
* the wikitext syntax is just for illustration):
*
* == A ==
* B. ~~~~
* : C.
* : C. ~~~~
* :: D. ~~~~
* ::: E. ~~~~
* ::: F. ~~~~
* : G. ~~~~
* H. ~~~~
* : I. ~~~~
*
* This function would return a structure like:
*
* [
* HeadingItem( { level: 0, range: (h2: A), replies: [
* CommentItem( { level: 1, range: (p: B), replies: [
* CommentItem( { level: 2, range: (li: C, li: C), replies: [
* CommentItem( { level: 3, range: (li: D), replies: [
* CommentItem( { level: 4, range: (li: E), replies: [] },
* CommentItem( { level: 4, range: (li: F), replies: [] },
* ] },
* ] },
* CommentItem( { level: 2, range: (li: G), replies: [] },
* ] },
* CommentItem( { level: 1, range: (p: H), replies: [
* CommentItem( { level: 2, range: (li: I), replies: [] },
* ] },
* ] } )
* ]
*
* @return HeadingItem[] Tree structure of comments, top-level items are the headings.
*/
public function getThreads() : array {
if ( !$this->threads ) {
$this->buildThreads();
}
return $this->threads;
}
/**
* Given a heading node, return the node on which the ID attribute is set.
*
* @param DOMElement $heading Heading node (`<h1>`-`<h6>`)
* @return DOMElement Headline node (same as the heading node, or one of its children)
*/
private function getHeadlineNode( DOMElement $heading ) {
// This code assumes that $wgFragmentMode is [ 'html5', 'legacy' ] or [ 'html5' ]
if (
( $node = $heading->firstChild ) &&
$node instanceof DOMElement &&
$node->getAttribute( 'class' ) === 'mw-headline'
) {
// Old parser, without fallback ID element
return $node;
} elseif (
$heading->firstChild &&
( $node = $heading->firstChild->nextSibling ) &&
$node instanceof DOMElement &&
$node->getAttribute( 'class' ) === 'mw-headline'
) {
// Old parser, with a fallback ID element before the headline
return $node;
} else {
// Parsoid (the heading node itself carries the ID)
return $heading;
}
}
/**
* Given a thread item, return an identifier for it that is unique within the page.
*
* @param ThreadItem $threadItem
* @return string|null
*/
private function computeId( ThreadItem $threadItem ) : ?string {
$id = null;
if ( $threadItem instanceof HeadingItem && $threadItem->isPlaceholderHeading() ) {
// The range points to the root note, using it like below results in silly values
$id = 'h|';
} elseif ( $threadItem instanceof HeadingItem ) {
$headline = $this->getHeadlineNode( $threadItem->getRange()->startContainer );
$id = 'h|' . ( $headline->getAttribute( 'id' ) ?? '' );
} elseif ( $threadItem instanceof CommentItem ) {
$id = 'c|' . ( $threadItem->getAuthor() ?? '' ) . '|' . $threadItem->getTimestamp();
// If there would be multiple comments with the same ID (i.e. the user left multiple comments
// in one edit, or within a minute), append sequential numbers
$number = 0;
while ( isset( $this->threadItemsById["$id|$number"] ) ) {
$number++;
}
$id = "$id|$number";
} else {
throw new MWException( 'Unknown ThreadItem type' );
}
return $id;
}
/**
* Given a thread item, return an identifier for it like computeId(), generated according to an
* older algorithm, so that we can still match IDs from cached data.
*
* @param ThreadItem $threadItem
* @return string|null
*/
private function computeLegacyId( ThreadItem $threadItem ) : ?string {
return null;
}
private function buildThreads() : void {
if ( !$this->threadItems ) {
$this->buildThreadItems();
}
$threads = [];
$replies = [];
$this->threadItemsById = [];
foreach ( $this->threadItems as $threadItem ) {
$id = $this->computeId( $threadItem );
if ( $id ) {
$this->threadItemsById[$id] = $threadItem;
}
$threadItem->setId( $id );
$legacyId = $this->computeLegacyId( $threadItem );
$threadItem->setLegacyId( $legacyId );
if ( $legacyId ) {
$this->threadItemsById[$legacyId] = $threadItem;
}
if ( count( $replies ) < $threadItem->getLevel() ) {
// Someone skipped an indentation level (or several). Pretend that the previous reply
// covers multiple indentation levels, so that following comments get connected to it.
$threadItem->addWarning( 'Comment skips indentation level' );
while ( count( $replies ) < $threadItem->getLevel() ) {
$replies[] = end( $replies );
}
}
if ( $threadItem instanceof HeadingItem ) {
// New root (thread)
$threads[] = $threadItem;
} elseif ( isset( $replies[ $threadItem->getLevel() - 1 ] ) ) {
// Add as a reply to the closest less-nested comment
$threadItem->setParent( $replies[ $threadItem->getLevel() - 1 ] );
$threadItem->getParent()->addReply( $threadItem );
} else {
$threadItem->addWarning( 'Comment could not be connected to a thread' );
}
$replies[ $threadItem->getLevel() ] = $threadItem;
// Cut off more deeply nested replies
array_splice( $replies, $threadItem->getLevel() + 1 );
}
$this->threads = $threads;
}
}