mediawiki-extensions-Discus.../includes/CommentParser.php
Theodore Dubois 4ca17b8c33 Support ISO 8601 timestamps in the parser
https://wikipesija.org is currently using ISO 8601 as the default date
format. The format is xnY-xnm-xnd"T"xnH:xni:xns and 'xn', 'm', and 's'
need support added.

Change-Id: I235098a578eb92ddd23ea47fa23d60df4b28f590
2023-06-17 11:36:43 -07:00

1191 lines
40 KiB
PHP

<?php
namespace MediaWiki\Extension\DiscussionTools;
use Config;
use DateInterval;
use DateTime;
use DateTimeImmutable;
use DateTimeZone;
use InvalidArgumentException;
use Language;
use LogicException;
use MalformedTitleException;
use MediaWiki\Extension\DiscussionTools\ThreadItem\ContentCommentItem;
use MediaWiki\Extension\DiscussionTools\ThreadItem\ContentHeadingItem;
use MediaWiki\Extension\DiscussionTools\ThreadItem\ContentThreadItem;
use MediaWiki\Languages\LanguageConverterFactory;
use RuntimeException;
use TitleParser;
use TitleValue;
use Wikimedia\Assert\Assert;
use Wikimedia\IPUtils;
use Wikimedia\Parsoid\DOM\Element;
use Wikimedia\Parsoid\DOM\Node;
use Wikimedia\Parsoid\DOM\Text;
use Wikimedia\Parsoid\Utils\DOMCompat;
// TODO consider making timestamp parsing not a returned function
class CommentParser {
/**
* How far backwards we look for a signature associated with a timestamp before giving up.
* Note that this is not a hard limit on the length of signatures we detect.
*/
private const SIGNATURE_SCAN_LIMIT = 100;
private Config $config;
private Language $language;
private LanguageConverterFactory $languageConverterFactory;
private TitleParser $titleParser;
private $dateFormat;
private $digits;
/** @var string[][] */
private $contLangMessages;
private $localTimezone;
private $timezones;
private $specialContributionsName;
private Element $rootNode;
private TitleValue $title;
/**
* @param Config $config
* @param Language $language Content language
* @param LanguageConverterFactory $languageConverterFactory
* @param LanguageData $languageData
* @param TitleParser $titleParser
*/
public function __construct(
Config $config,
Language $language,
LanguageConverterFactory $languageConverterFactory,
LanguageData $languageData,
TitleParser $titleParser
) {
$this->config = $config;
$this->language = $language;
$this->languageConverterFactory = $languageConverterFactory;
$this->titleParser = $titleParser;
$data = $languageData->getLocalData();
$this->dateFormat = $data['dateFormat'];
$this->digits = $data['digits'];
$this->contLangMessages = $data['contLangMessages'];
$this->localTimezone = $data['localTimezone'];
$this->timezones = $data['timezones'];
$this->specialContributionsName = $data['specialContributionsName'];
}
/**
* Parse a discussion page.
*
* @param Element $rootNode Root node of content to parse
* @param TitleValue $title Title of the page being parsed
* @return ContentThreadItemSet
*/
public function parse( Element $rootNode, TitleValue $title ): ContentThreadItemSet {
$this->rootNode = $rootNode;
$this->title = $title;
$result = $this->buildThreadItems();
$this->buildThreads( $result );
$this->computeIdsAndNames( $result );
return $result;
}
/**
* 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 Element node
* that is a "void element" or "text element", except some special cases that we treat as comment
* separators (isCommentSeparator()).
*
* @param Node $node Node to start searching at. This node's children are ignored.
* @return Node
*/
private function nextInterestingLeafNode( Node $node ): Node {
$rootNode = $this->rootNode;
$treeWalker = new TreeWalker(
$rootNode,
NodeFilter::SHOW_ELEMENT | NodeFilter::SHOW_TEXT,
static 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;
}
// Ignore some elements usually used as separators or headers (and their descendants)
if ( CommentUtils::isCommentSeparator( $n ) ) {
return NodeFilter::FILTER_REJECT;
}
// Ignore nodes with no rendering that mess up our indentation detection
if ( CommentUtils::isRenderingTransparentNode( $n ) ) {
return NodeFilter::FILTER_REJECT;
}
if ( CommentUtils::isCommentContent( $n ) ) {
return NodeFilter::FILTER_ACCEPT;
}
return NodeFilter::FILTER_SKIP;
}
);
$treeWalker->currentNode = $node;
$treeWalker->nextNode();
if ( !$treeWalker->currentNode ) {
throw new RuntimeException( '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( static 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 = '';
$raw = false;
// 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 .= static::regexpAlternateGroup(
$this->getMessages( $contLangVariant, Language::MONTH_GENITIVE_MESSAGES )
);
break;
case 'xn':
$raw = true;
break;
case 'd':
$num = '2';
break;
case 'D':
$s .= static::regexpAlternateGroup(
$this->getMessages( $contLangVariant, Language::WEEKDAY_ABBREVIATED_MESSAGES )
);
break;
case 'j':
$num = '1,2';
break;
case 'l':
$s .= static::regexpAlternateGroup(
$this->getMessages( $contLangVariant, Language::WEEKDAY_MESSAGES )
);
break;
case 'F':
$s .= static::regexpAlternateGroup(
$this->getMessages( $contLangVariant, Language::MONTH_MESSAGES )
);
break;
case 'M':
$s .= static::regexpAlternateGroup(
$this->getMessages( $contLangVariant, Language::MONTH_ABBREVIATED_MESSAGES )
);
break;
case 'm':
$num = '2';
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 's':
$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:
// Copy whole characters together, instead of single bytes
$char = mb_substr( mb_strcut( $format, $p, 4 ), 0, 1 );
$s .= preg_quote( $char, '/' );
$p += strlen( $char ) - 1;
}
if ( $num !== false ) {
if ( $raw ) {
$s .= '([0-9]{' . $num . '})';
$raw = false;
} else {
$s .= '(' . $digitsRegexp . '{' . $num . '})';
}
}
// Ignore some invisible Unicode characters that often sneak into copy-pasted timestamps (T308448)
$s .= '[\\x{200E}\\x{200F}]?';
}
$tzRegexp = static::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}]?\\(' . $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 = static function ( string $text ) use ( $digits ) {
if ( !$digits ) {
return $text;
}
return preg_replace_callback(
'/[' . implode( '', $digits ) . ']/u',
static 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':
case 'xn':
break;
case 'xg':
case 'd':
case 'j':
case 'D':
case 'l':
case 'F':
case 'M':
case 'm':
case 'n':
case 'Y':
case 'xkY':
case 'G':
case 'H':
case 'i':
case 's':
$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( static 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 'm':
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;
case 's':
// Seconds - unused, because most timestamp formats omit them
break;
default:
throw new LogicException( '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.
$dateWarning = null;
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;
$dateWarning = 'Timestamp has timezone abbreviation for the wrong time';
} else {
$dateWarning = '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 );
return [
'date' => $date,
'warning' => $dateWarning,
];
};
}
/**
* 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 {
$langConv = $this->languageConverterFactory->getLanguageConverter( $this->language );
return array_map( function ( $contLangVariant ) {
return $this->getTimestampRegexp(
$contLangVariant,
$this->dateFormat[$contLangVariant],
'[' . implode( '', $this->digits[$contLangVariant] ) . ']',
$this->timezones[$contLangVariant]
);
}, $langConv->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 {
$langConv = $this->languageConverterFactory->getLanguageConverter( $this->language );
return array_map( function ( $contLangVariant ) {
return $this->getTimestampParser(
$contLangVariant,
$this->dateFormat[$contLangVariant],
$this->digits[$contLangVariant],
$this->localTimezone,
$this->timezones[$contLangVariant]
);
}, $langConv->getVariants() );
}
/**
* Given a link node (`<a>`), if it's a link to a user-related page, return their username.
*
* @param Element $link
* @return array|null Array, or null:
* - string 'username' Username
* - string|null 'displayName' Display name (link text if link target was in the user namespace)
*/
private function getUsernameFromLink( Element $link ): ?array {
// Selflink: use title of current page
if ( DOMCompat::getClassList( $link )->contains( 'mw-selflink' ) ) {
$title = $this->title;
} else {
$titleString = CommentUtils::getTitleFromUrl( $link->getAttribute( 'href' ) ?? '', $this->config ) ?? '';
try {
$title = $this->titleParser->parseTitle( $titleString );
} catch ( MalformedTitleException $err ) {
return null;
}
}
$username = null;
$displayName = null;
$namespaceId = $title->getNamespace();
$mainText = $title->getText();
if ( $namespaceId === NS_USER || $namespaceId === NS_USER_TALK ) {
$username = $mainText;
if ( str_contains( $username, '/' ) ) {
return null;
}
if ( $namespaceId === NS_USER ) {
// Use regex trim for consistency with JS implementation
$text = preg_replace( [ '/^[\s]+/u', '/[\s]+$/u' ], '', $link->textContent ?? '' );
// Record the display name if it has been customised beyond changing case
if ( $text && mb_strtolower( $text ) !== mb_strtolower( $username ) ) {
$displayName = $text;
}
}
} elseif ( $namespaceId === NS_SPECIAL ) {
$parts = explode( '/', $mainText );
if ( count( $parts ) === 2 && $parts[0] === $this->specialContributionsName ) {
// Normalize the username: users may link to their contributions with an unnormalized name
$userpage = $this->titleParser->makeTitleValueSafe( NS_USER, $parts[1] );
if ( !$userpage ) {
return null;
}
$username = $userpage->getText();
}
}
if ( !$username ) {
return null;
}
if ( IPUtils::isIPv6( $username ) ) {
// Bot-generated links "Preceding unsigned comment added by" have non-standard case
$username = strtoupper( $username );
}
return [
'username' => $username,
'displayName' => $displayName,
];
}
/**
* 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.
*
* @param Text $timestampNode
* @param Node|null $until Node to stop searching at
* @return array Result, an associative array with the following keys:
* - Node[] `nodes` Sibling nodes comprising the signature, in reverse order (with
* $timestampNode or its parent node as the first element)
* - string|null `username` Username, null for unsigned comments
*/
private function findSignature( Text $timestampNode, ?Node $until = null ): array {
$sigUsername = null;
$sigDisplayName = null;
$length = 0;
$lastLinkNode = $timestampNode;
CommentUtils::linearWalkBackwards(
$timestampNode,
function ( string $event, Node $node ) use (
&$sigUsername, &$sigDisplayName, &$lastLinkNode, &$length,
$until, $timestampNode
) {
if ( $event === 'enter' && $node === $until ) {
return true;
}
if ( $length >= static::SIGNATURE_SCAN_LIMIT ) {
return true;
}
if ( CommentUtils::isBlockElement( $node ) ) {
// Don't allow reaching into preceding paragraphs
return true;
}
if ( $event === 'leave' && $node !== $timestampNode ) {
$length += $node instanceof Text ?
mb_strlen( CommentUtils::htmlTrim( $node->textContent ?? '' ) ) : 0;
}
// Find the closest link before timestamp that links to the user's user page.
//
// 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
//
// Handle links nested in formatting elements.
if ( $event === 'leave' && $node instanceof Element && strtolower( $node->tagName ) === 'a' ) {
$user = $this->getUsernameFromLink( $node );
if ( $user ) {
// Accept the first link to the user namespace, then only accept links to that user
if ( $sigUsername === null ) {
$sigUsername = $user['username'];
}
if ( $user['username'] === $sigUsername ) {
$lastLinkNode = $node;
if ( $user['displayName'] ) {
$sigDisplayName = $user['displayName'];
}
}
}
// Keep looking if a node with links wasn't a link to a user page
// "Doc James (talk · contribs · email)"
}
}
);
$range = new ImmutableRange(
$lastLinkNode->parentNode,
CommentUtils::childIndexOf( $lastLinkNode ),
$timestampNode->parentNode,
CommentUtils::childIndexOf( $timestampNode ) + 1
);
// Expand the range so that it covers sibling nodes.
// This will include any wrapping formatting elements as part of the signature.
//
// 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 »"
//
// TODO Not sure if this is actually good, might be better to just use the range...
$sigNodes = array_reverse( CommentUtils::getCoveredSiblings( $range ) );
return [
'nodes' => $sigNodes,
'username' => $sigUsername,
'displayName' => $sigDisplayName,
];
}
/**
* Callback for TreeWalker that will skip over nodes where we don't want to detect
* comments (or section headings).
*
* @param Node $node
* @return int Appropriate NodeFilter constant
*/
public static function acceptOnlyNodesAllowingComments( Node $node ): int {
if ( $node instanceof Element ) {
$tagName = strtolower( $node->tagName );
// The table of contents has a heading that gets erroneously detected as a section
if ( $node->getAttribute( 'id' ) === 'toc' ) {
return NodeFilter::FILTER_REJECT;
}
// Don't detect comments within quotes (T275881)
if (
$tagName === 'blockquote' ||
$tagName === 'cite' ||
$tagName === 'q'
) {
return NodeFilter::FILTER_REJECT;
}
$classList = DOMCompat::getClassList( $node );
// Don't attempt to parse blocks marked 'mw-notalk'
if ( $classList->contains( 'mw-notalk' ) ) {
return NodeFilter::FILTER_REJECT;
}
// Don't detect comments within references. We can't add replies to them without bungling up
// the structure in some cases (T301213), and you're not supposed to do that anyway…
if (
// <ol class="references"> is the only reliably consistent thing between the two parsers
$tagName === 'ol' &&
DOMCompat::getClassList( $node )->contains( 'references' )
) {
return NodeFilter::FILTER_REJECT;
}
}
$parentNode = $node->parentNode;
// Don't detect comments within headings (but don't reject the headings themselves)
if ( $parentNode instanceof Element && preg_match( '/^h([1-6])$/i', $parentNode->tagName ) ) {
return NodeFilter::FILTER_REJECT;
}
return NodeFilter::FILTER_ACCEPT;
}
/**
* Convert a byte offset within a text node to a unicode codepoint offset
*
* @param Text $node Text node
* @param int $byteOffset Byte offset
* @return int Codepoint offset
*/
private static function getCodepointOffset( Text $node, int $byteOffset ): int {
return mb_strlen( substr( $node->nodeValue ?? '', 0, $byteOffset ) );
}
/**
* Find a timestamps in a given text node
*
* @param Text $node
* @param string[] $timestampRegexps
* @return array|null Array with the following keys:
* - int 'offset' Length of extra text preceding the node that was used for matching (in bytes)
* - 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() (offsets are in bytes)
* - ImmutableRange 'range' Range covering the timestamp
*/
public function findTimestamp( Text $node, array $timestampRegexps ): ?array {
$nodeText = '';
$offset = 0;
// Searched nodes (reverse order)
$nodes = [];
while ( $node ) {
$nodeText = $node->nodeValue . $nodeText;
$nodes[] = $node;
// 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 Element &&
$previousSibling->getAttribute( 'typeof' ) === 'mw:Entity'
) {
$nodeText = $previousSibling->firstChild->nodeValue . $nodeText;
$offset += strlen( $previousSibling->firstChild->nodeValue ?? '' );
$nodes[] = $previousSibling->firstChild;
// If the entity is preceded by more text, do this again
if (
$previousSibling->previousSibling &&
$previousSibling->previousSibling instanceof Text
) {
$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 ) ) {
$timestampLength = strlen( $matchData[0][0] );
// Bytes at the end of the last node which aren't part of the match
$tailLength = strlen( $nodeText ) - $timestampLength - $matchData[0][1];
// We are moving right to left, but we start to the right of the end of
// the timestamp if there is trailing garbage, so that is a negative offset.
$count = -$tailLength;
$endNode = $nodes[0];
$endOffset = strlen( $endNode->nodeValue ?? '' ) - $tailLength;
foreach ( $nodes as $n ) {
$count += strlen( $n->nodeValue ?? '' );
// If we have counted to beyond the start of the timestamp, we are in the
// start node of the timestamp
if ( $count >= $timestampLength ) {
$startNode = $n;
// Offset is how much we overshot the start by
$startOffset = $count - $timestampLength;
break;
}
}
Assert::precondition( $endNode instanceof Node, 'endNode of timestamp is a Node' );
Assert::precondition( $startNode instanceof Node, 'startNode of timestamp range found' );
Assert::precondition( is_int( $startOffset ), 'startOffset of timestamp range found' );
$startOffset = static::getCodepointOffset( $startNode, $startOffset );
$endOffset = static::getCodepointOffset( $endNode, $endOffset );
$range = new ImmutableRange( $startNode, $startOffset, $endNode, $endOffset );
return [
'matchData' => $matchData,
// Bytes at the start of the first node which aren't part of the match
// TODO: Remove this and use 'range' instead
'offset' => $offset,
'range' => $range,
'parserIndex' => $i,
];
}
}
return null;
}
/**
* @param Node[] $sigNodes
* @param array $match
* @param Text $node
* @return ImmutableRange
*/
private function adjustSigRange( array $sigNodes, array $match, Text $node ): ImmutableRange {
$firstSigNode = end( $sigNodes );
$lastSigNode = $sigNodes[0];
// TODO Document why this needs to be so complicated
$lastSigNodeOffsetByteOffset =
$match['matchData'][0][1] + strlen( $match['matchData'][0][0] ) - $match['offset'];
$lastSigNodeOffset = $lastSigNode === $node ?
static::getCodepointOffset( $node, $lastSigNodeOffsetByteOffset ) :
CommentUtils::childIndexOf( $lastSigNode ) + 1;
$sigRange = new ImmutableRange(
$firstSigNode->parentNode,
CommentUtils::childIndexOf( $firstSigNode ),
$lastSigNode === $node ? $node : $lastSigNode->parentNode,
$lastSigNodeOffset
);
return $sigRange;
}
private function buildThreadItems(): ContentThreadItemSet {
$result = new ContentThreadItemSet();
$timestampRegexps = $this->getLocalTimestampRegexps();
$dfParsers = $this->getLocalTimestampParsers();
$curCommentEnd = $this->rootNode;
$treeWalker = new TreeWalker(
$this->rootNode,
NodeFilter::SHOW_ELEMENT | NodeFilter::SHOW_TEXT,
[ static::class, 'acceptOnlyNodesAllowingComments' ]
);
$lastSigNode = null;
while ( $node = $treeWalker->nextNode() ) {
if ( $node instanceof Element && preg_match( '/^h([1-6])$/i', $node->tagName, $match ) ) {
$headingNodeAndOffset = CommentUtils::getHeadlineNodeAndOffset( $node );
$headingNode = $headingNodeAndOffset['node'];
$startOffset = $headingNodeAndOffset['offset'];
$range = new ImmutableRange(
$headingNode, $startOffset, $headingNode, $headingNode->childNodes->length
);
$curComment = new ContentHeadingItem( $range, (int)( $match[ 1 ] ) );
$curComment->setRootNode( $this->rootNode );
$result->addThreadItem( $curComment );
$curCommentEnd = $node;
} elseif ( $node instanceof Text && ( $match = $this->findTimestamp( $node, $timestampRegexps ) ) ) {
$warnings = [];
$foundSignature = $this->findSignature( $node, $lastSigNode );
$author = $foundSignature['username'];
$lastSigNode = $foundSignature['nodes'][0];
if ( !$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;
}
$sigRanges = [];
$timestampRanges = [];
$sigRanges[] = $this->adjustSigRange( $foundSignature['nodes'], $match, $node );
$timestampRanges[] = $match['range'];
// Everything from the last comment up to here is the next comment
$startNode = $this->nextInterestingLeafNode( $curCommentEnd );
$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.
//
// If this skips over another potential signature, also skip it in the main TreeWalker loop, to
// 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).
CommentUtils::linearWalk(
$lastSigNode,
function ( string $event, Node $n ) use (
&$endNode, &$sigRanges, &$timestampRanges,
$treeWalker, $timestampRegexps, $node
) {
if ( CommentUtils::isBlockElement( $n ) || CommentUtils::isCommentSeparator( $n ) ) {
// Stop when entering or leaving a block node
return true;
}
if (
$event === 'leave' &&
$n instanceof Text && $n !== $node &&
( $match2 = $this->findTimestamp( $n, $timestampRegexps ) )
) {
// If this skips over another potential signature, also skip it in the main TreeWalker loop
$treeWalker->currentNode = $n;
// …and add it as another signature to this comment (regardless of the author and timestamp)
$foundSignature2 = $this->findSignature( $n, $node );
if ( $foundSignature2['username'] ) {
$sigRanges[] = $this->adjustSigRange( $foundSignature2['nodes'], $match2, $n );
$timestampRanges[] = $match2['range'];
}
}
if ( $event === 'leave' ) {
// Take the last complete node which we skipped past
$endNode = $n;
}
}
);
$length = ( $endNode instanceof Text ) ?
mb_strlen( rtrim( $endNode->nodeValue ?? '', "\t\n\f\r " ) ) :
// PHP bug: childNodes can be null for comment nodes
// (it should always be a NodeList, 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 );
[ 'date' => $dateTime, 'warning' => $dateWarning ] =
$dfParsers[ $match['parserIndex'] ]( $match['matchData'] );
if ( $dateWarning ) {
$warnings[] = $dateWarning;
}
$curComment = new ContentCommentItem(
$level,
$range,
$sigRanges,
$timestampRanges,
$dateTime,
$author,
$foundSignature['displayName']
);
$curComment->setRootNode( $this->rootNode );
if ( $warnings ) {
$curComment->addWarnings( $warnings );
}
if ( $result->isEmpty() ) {
// Add a fake placeholder heading if there are any comments in the 0th section
// (before the first real heading)
$range = new ImmutableRange( $this->rootNode, 0, $this->rootNode, 0 );
$fakeHeading = new ContentHeadingItem( $range, null );
$fakeHeading->setRootNode( $this->rootNode );
$result->addThreadItem( $fakeHeading );
}
$result->addThreadItem( $curComment );
$curCommentEnd = $curComment->getRange()->endContainer;
}
}
return $result;
}
/**
* Truncate user generated parts of IDs so full ID always fits within a database field of length 255
*
* @param string $text Text
* @return string Truncated text
*/
private function truncateForId( string $text ): string {
return $this->language->truncateForDatabase( $text, 80, '' );
}
/**
* Given a thread item, return an identifier for it that is unique within the page.
*
* @param ContentThreadItem $threadItem
* @param ContentThreadItemSet $previousItems
* @return string
*/
private function computeId( ContentThreadItem $threadItem, ContentThreadItemSet $previousItems ): string {
$id = null;
if ( $threadItem instanceof ContentHeadingItem && $threadItem->isPlaceholderHeading() ) {
// The range points to the root note, using it like below results in silly values
$id = 'h-';
} elseif ( $threadItem instanceof ContentHeadingItem ) {
// <span class="mw-headline" …>, or <hN …> in Parsoid HTML
$headline = $threadItem->getRange()->startContainer;
Assert::precondition( $headline instanceof Element, 'HeadingItem refers to an element node' );
$id = 'h-' . $this->truncateForId( $headline->getAttribute( 'id' ) ?? '' );
} elseif ( $threadItem instanceof ContentCommentItem ) {
$id = 'c-' . $this->truncateForId( str_replace( ' ', '_', $threadItem->getAuthor() ) ) .
'-' . $threadItem->getTimestampString();
} else {
throw new InvalidArgumentException( 'Unknown ThreadItem type' );
}
// If there would be multiple comments with the same ID (i.e. the user left multiple comments
// in one edit, or within a minute), add the parent ID to disambiguate them.
$threadItemParent = $threadItem->getParent();
if ( $threadItemParent instanceof ContentHeadingItem && !$threadItemParent->isPlaceholderHeading() ) {
// <span class="mw-headline" …>, or <hN …> in Parsoid HTML
$headline = $threadItemParent->getRange()->startContainer;
Assert::precondition( $headline instanceof Element, 'HeadingItem refers to an element node' );
$id .= '-' . $this->truncateForId( $headline->getAttribute( 'id' ) ?? '' );
} elseif ( $threadItemParent instanceof ContentCommentItem ) {
$id .= '-' . $this->truncateForId( str_replace( ' ', '_', $threadItemParent->getAuthor() ) ) .
'-' . $threadItemParent->getTimestampString();
}
if ( $threadItem instanceof ContentHeadingItem ) {
// To avoid old threads re-appearing on popular pages when someone uses a vague title
// (e.g. dozens of threads titled "question" on [[Wikipedia:Help desk]]: https://w.wiki/fbN),
// include the oldest timestamp in the thread (i.e. date the thread was started) in the
// heading ID.
$oldestComment = $threadItem->getOldestReply();
if ( $oldestComment ) {
$id .= '-' . $oldestComment->getTimestampString();
}
}
if ( $previousItems->findCommentById( $id ) ) {
// Well, that's tough
$threadItem->addWarning( 'Duplicate comment ID' );
// Finally, disambiguate by adding sequential numbers, to allow replying to both comments
$number = 1;
while ( $previousItems->findCommentById( "$id-$number" ) ) {
$number++;
}
$id = "$id-$number";
}
return $id;
}
/**
* Given a thread item, return an identifier for it that is consistent across all pages and
* revisions where this comment might appear.
*
* Multiple comments on a page can have the same name; use ID to distinguish them.
*
* @param ContentThreadItem $threadItem
* @return string
*/
private function computeName( ContentThreadItem $threadItem ): string {
$name = null;
if ( $threadItem instanceof ContentHeadingItem ) {
$name = 'h-';
$mainComment = $threadItem->getOldestReply();
} elseif ( $threadItem instanceof ContentCommentItem ) {
$name = 'c-';
$mainComment = $threadItem;
} else {
throw new InvalidArgumentException( 'Unknown ThreadItem type' );
}
if ( $mainComment ) {
$name .= $this->truncateForId( str_replace( ' ', '_', $mainComment->getAuthor() ) ) .
'-' . $mainComment->getTimestampString();
}
return $name;
}
/**
* @param ContentThreadItemSet $result
*/
private function buildThreads( ContentThreadItemSet $result ): void {
$lastHeading = null;
$replies = [];
foreach ( $result->getThreadItems() as $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 ContentHeadingItem ) {
// New root (thread)
// Attach as a sub-thread to preceding higher-level heading.
// Any replies will appear in the tree twice, under the main-thread and the sub-thread.
$maybeParent = $lastHeading;
while ( $maybeParent && $maybeParent->getHeadingLevel() >= $threadItem->getHeadingLevel() ) {
$maybeParent = $maybeParent->getParent();
}
if ( $maybeParent ) {
$threadItem->setParent( $maybeParent );
$maybeParent->addReply( $threadItem );
}
$lastHeading = $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 );
}
}
/**
* Set the IDs and names used to refer to comments and headings.
* This has to be a separate pass because we don't have the list of replies before
* this point.
*
* @param ContentThreadItemSet $result
*/
private function computeIdsAndNames( ContentThreadItemSet $result ): void {
foreach ( $result->getThreadItems() as $threadItem ) {
$name = $this->computeName( $threadItem );
$threadItem->setName( $name );
$id = $this->computeId( $threadItem, $result );
$threadItem->setId( $id );
$result->updateIdAndNameMaps( $threadItem );
}
}
}