mediawiki-extensions-Discus.../includes/CommentModifier.php

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<?php
namespace MediaWiki\Extension\DiscussionTools;
use DOMComment;
use DOMDocument;
use DOMDocumentFragment;
use DOMElement;
use DOMNode;
use DOMText;
use DOMXPath;
use Wikimedia\Parsoid\Utils\DOMCompat;
class CommentModifier {
private function __construct() {
}
/**
* Add an attribute to a list item to remove pre-whitespace in Parsoid
*
* @param DOMElement $listItem
*/
private static function whitespaceParsoidHack( DOMElement $listItem ) : void {
// HACK: Setting data-parsoid removes the whitespace after the list item,
// which makes nested lists work.
// This is undocumented behaviour and probably very fragile.
$listItem->setAttribute( 'data-parsoid', '{}' );
}
/**
* Remove extra linebreaks from a wikitext string
*
* @param string $wikitext
* @return string
*/
public static function sanitizeWikitextLinebreaks( string $wikitext ) : string {
$wikitext = CommentUtils::htmlTrim( $wikitext );
$wikitext = preg_replace( "/\r/", "\n", $wikitext );
$wikitext = preg_replace( "/\n+/", "\n", $wikitext );
return $wikitext;
}
/**
* Given a comment and a reply link, add the reply link to its document's DOM tree, at the end of
* the comment.
*
* @param CommentItem $comment
* @param DOMElement $linkNode Reply link
*/
public static function addReplyLink( CommentItem $comment, DOMElement $linkNode ) : void {
$target = $comment->getRange()->endContainer;
// Insert the link before trailing whitespace.
// In the MediaWiki parser output, <ul>/<dl> nodes are preceded by a newline. Normally it isn't
// visible on the page. But if we insert an inline element (the reply link) after it, it becomes
// meaningful and gets rendered, which results in additional spacing before some reply links.
// Split the text node, so that we can insert the link before the trailing whitespace.
if ( $target->nodeType === XML_TEXT_NODE ) {
preg_match( '/\s*$/', $target->nodeValue, $matches, PREG_OFFSET_CAPTURE );
$byteOffset = $matches[0][1];
$charOffset = mb_strlen(
substr( $target->nodeValue, 0, $byteOffset )
);
$target->splitText( $charOffset );
}
$target->parentNode->insertBefore( $linkNode, $target->nextSibling );
}
/**
* Given a comment, add a list item to its document's DOM tree, inside of which a reply to said
* comment can be added.
*
* The DOM tree is suitably rearranged to ensure correct indentation level of the reply (wrapper
* nodes are added, and other nodes may be moved around).
*
* @param CommentItem $comment
* @return DOMElement
*/
public static function addListItem( CommentItem $comment ) : DOMElement {
$listTypeMap = [
'li' => 'ul',
'dd' => 'dl'
];
// 1. Start at given comment
// 2. Skip past all comments with level greater than the given
// (or in other words, all replies, and replies to replies, and so on)
// 3. Add comment with level of the given comment plus 1
$curComment = $comment;
while ( count( $curComment->getReplies() ) ) {
$replies = $curComment->getReplies();
$curComment = end( $replies );
}
// Tag names for lists and items we're going to insert
// TODO Add an option to prefer bulleted lists (ul/li)
$itemType = 'dd';
$listType = $listTypeMap[ $itemType ];
$desiredLevel = $comment->getLevel() + 1;
$target = $curComment->getRange()->endContainer;
// target is a text node or an inline element at the end of a "paragraph"
// (not necessarily paragraph node).
// First, we need to find a block-level parent that we can mess with.
// If we can't find a surrounding list item or paragraph (e.g. maybe we're inside a table cell
// or something), take the parent node and hope for the best.
$parent = CommentUtils::closestElement( $target, [ 'li', 'dd', 'p' ] ) ??
$target->parentNode;
while ( $target->parentNode !== $parent ) {
$target = $target->parentNode;
}
// parent is a list item or paragraph (hopefully)
// target is an inline node within it
// Instead of just using $curComment->getLevel(), consider indentation of lists within the
// comment (T252702)
$curLevel = CommentUtils::getIndentLevel( $target, $curComment->getRootNode() ) + 1;
$item = null;
if ( $curLevel < $desiredLevel ) {
// Insert more lists after the target to increase nesting.
// If the comment is fully covered by some wrapper element, insert replies outside that wrapper.
// This will often just be a paragraph node (<p>), but it can be a <div> or <table> that serves
// as some kind of a fancy frame, which are often used for barnstars and announcements.
$covered = CommentUtils::getFullyCoveredSiblings( $curComment );
if ( $curLevel === 1 && $covered ) {
$target = end( $covered );
$parent = $target->parentNode;
}
// If we can't insert a list directly inside this element, insert after it.
// TODO Figure out if this is still needed, the wrapper check above should handle all cases
if ( strtolower( $parent->tagName ) === 'p' || strtolower( $parent->tagName ) === 'pre' ) {
$parent = $parent->parentNode;
$target = $target->parentNode;
}
// Parsoid puts HTML comments which appear at the end of the line in wikitext outside the paragraph,
// but we usually shouldn't insert replies between the paragraph and such comments. (T257651)
// Skip over comments and whitespace, but only update target when skipping past comments.
$pointer = $target;
while (
$pointer->nextSibling && (
$pointer->nextSibling instanceof DOMComment ||
(
$pointer->nextSibling instanceof DOMText &&
CommentUtils::htmlTrim( $pointer->nextSibling->nodeValue ) === '' &&
// If more that two lines of whitespace are detected, the following HTML
// comments are not considered to be part of the reply (T264026)
!preg_match( '/(\r?\n){2,}/', $pointer->nextSibling->nodeValue )
)
)
) {
$pointer = $pointer->nextSibling;
if ( $pointer instanceof DOMComment ) {
$target = $pointer;
}
}
// Insert required number of wrappers
while ( $curLevel < $desiredLevel ) {
$list = $target->ownerDocument->createElement( $listType );
// Setting modified would only be needed for removeAddedListItem,
// which isn't needed on the server
// $list->setAttribute( 'dt-modified', 'new' );
$item = $target->ownerDocument->createElement( $itemType );
// $item->setAttribute( 'dt-modified', 'new' );
self::whitespaceParsoidHack( $item );
$parent->insertBefore( $list, $target->nextSibling );
$list->appendChild( $item );
$target = $item;
$parent = $list;
$curLevel++;
}
} else {
// Split the ancestor nodes after the target to decrease nesting.
do {
// If target is the last child of its parent, no need to split it
if ( $target->nextSibling ) {
// Create new identical node after the parent
$newNode = $parent->cloneNode( false );
// $parent->setAttribute( 'dt-modified', 'split' );
$parent->parentNode->insertBefore( $newNode, $parent->nextSibling );
// Move nodes following target to the new node
while ( $target->nextSibling ) {
$newNode->appendChild( $target->nextSibling );
}
}
$target = $parent;
$parent = $parent->parentNode;
// Decrease nesting level if we escaped outside of a list
if ( isset( $listTypeMap[ strtolower( $target->tagName ) ] ) ) {
$curLevel--;
}
} while ( $curLevel >= $desiredLevel );
// parent is now a list, target is a list item
if ( $itemType === strtolower( $target->tagName ) ) {
$item = $target->ownerDocument->createElement( $itemType );
// $item->setAttribute( 'dt-modified', 'new' );
self::whitespaceParsoidHack( $item );
$parent->insertBefore( $item, $target->nextSibling );
} else {
// This is the wrong type of list, split it one more time
// If target is the last child of its parent, no need to split it
if ( $target->nextSibling ) {
// Create new identical node after the parent
$newNode = $parent->cloneNode( false );
// $parent->setAttribute( 'dt-modified', 'split' );
$parent->parentNode->insertBefore( $newNode, $parent->nextSibling );
// Move nodes following target to the new node
while ( $target->nextSibling ) {
$newNode->appendChild( $target->nextSibling );
}
}
$target = $parent;
$parent = $parent->parentNode;
// Insert a list of the right type in the middle
$list = $target->ownerDocument->createElement( $listType );
// Setting modified would only be needed for removeAddedListItem,
// which isn't needed on the server
// $list->setAttribute( 'dt-modified', 'new' );
$item = $target->ownerDocument->createElement( $itemType );
// $item->setAttribute( 'dt-modified', 'new' );
self::whitespaceParsoidHack( $item );
$parent->insertBefore( $list, $target->nextSibling );
$list->appendChild( $item );
}
}
if ( $item === null ) {
throw new \LogicException( __METHOD__ . ' no item found' );
}
return $item;
}
/**
* Check all elements in a node list are of a given type
*
* Also returns false if there are no elements in the list
*
* @param DOMNode[] $nodes Node list
* @param string $type Element type
* @return bool
*/
private static function allOfType( array $nodes, string $type ) : bool {
$hasElements = false;
foreach ( $nodes as $node ) {
if ( $node->nodeType === XML_ELEMENT_NODE ) {
if ( strtolower( $node->nodeName ) !== strtolower( $type ) ) {
return false;
}
$hasElements = true;
}
}
return $hasElements;
}
/**
* Remove unnecessary list wrappers from a comment fragment
*
* TODO: Implement this in JS if required
*
* @param DOMDocumentFragment $fragment Fragment
*/
public static function unwrapFragment( DOMDocumentFragment $fragment ) {
$childNodeList = iterator_to_array( $fragment->childNodes );
// Wrap orphaned list items
$list = null;
if ( self::allOfType( $childNodeList, 'dd' ) ) {
$list = $fragment->ownerDocument->createElement( 'dl' );
} elseif ( self::allOfType( $childNodeList, 'li' ) ) {
$list = $fragment->ownerDocument->createElement( 'ul' );
}
if ( $list ) {
while ( $fragment->firstChild ) {
$list->appendChild( $fragment->firstChild );
}
$fragment->appendChild( $list );
}
// If all child nodes are lists of the same type, unwrap them
while (
( $childNodeList = iterator_to_array( $fragment->childNodes ) ) && (
self::allOfType( $childNodeList, 'dl' ) ||
self::allOfType( $childNodeList, 'ul' ) ||
self::allOfType( $childNodeList, 'ol' )
)
) {
foreach ( $childNodeList as $node ) {
self::unwrapList( $node, $fragment );
}
}
}
// removeAddedListItem is only needed in the client
/**
* Unwrap a top level list, converting list item text to paragraphs
*
* Assumes that the list has a parent node, or is a root child in the provided
* document fragment.
*
* @param DOMnode $list DOM node, will be wrapped if it is a list element (dl/ol/ul)
* @param DOMDocumentFragment|null $fragment Containing document fragment if list has no parent
*/
public static function unwrapList( DOMnode $list, ?DOMDocumentFragment $fragment = null ) : void {
$doc = $list->ownerDocument;
$container = $fragment ?: $list->parentNode;
$referenceNode = $list;
if ( !(
$list instanceof DOMElement && (
strtolower( $list->tagName ) === 'dl' ||
strtolower( $list->tagName ) === 'ol' ||
strtolower( $list->tagName ) === 'ul'
)
) ) {
// Not a list, leave alone (e.g. auto-generated ref block)
return;
}
// If the whole list is a template return it unmodified (T253150)
if ( CommentUtils::getTranscludedFromElement( $list ) ) {
return;
}
while ( $list->firstChild ) {
if ( $list->firstChild->nodeType === XML_ELEMENT_NODE ) {
// Move <dd> contents to <p>
$p = $doc->createElement( 'p' );
while ( $list->firstChild->firstChild ) {
// If contents is a block element, place outside the paragraph
// and start a new paragraph after
if ( CommentUtils::isBlockElement( $list->firstChild->firstChild ) ) {
if ( $p->firstChild ) {
$insertBefore = $referenceNode->nextSibling;
$referenceNode = $p;
$container->insertBefore( $p, $insertBefore );
}
$insertBefore = $referenceNode->nextSibling;
$referenceNode = $list->firstChild->firstChild;
$container->insertBefore( $list->firstChild->firstChild, $insertBefore );
$p = $doc->createElement( 'p' );
} else {
$p->appendChild( $list->firstChild->firstChild );
}
}
if ( $p->firstChild ) {
$insertBefore = $referenceNode->nextSibling;
$referenceNode = $p;
$container->insertBefore( $p, $insertBefore );
}
$list->removeChild( $list->firstChild );
} else {
// Text node / comment node, probably empty
$insertBefore = $referenceNode->nextSibling;
$referenceNode = $list->firstChild;
$container->insertBefore( $list->firstChild, $insertBefore );
}
}
$container->removeChild( $list );
}
/**
* Add another list item after the given one.
*
* @param DOMElement $previousItem
* @return DOMElement
*/
public static function addSiblingListItem( DOMElement $previousItem ) : DOMElement {
$listItem = $previousItem->ownerDocument->createElement( $previousItem->tagName );
self::whitespaceParsoidHack( $listItem );
$previousItem->parentNode->insertBefore( $listItem, $previousItem->nextSibling );
return $listItem;
}
/**
* Create an element that will convert to the provided wikitext
*
* @param DOMDocument $doc
* @param string $wikitext
* @return DOMElement
*/
public static function createWikitextNode( DOMDocument $doc, string $wikitext ) : DOMElement {
$span = $doc->createElement( 'span' );
$span->setAttribute( 'typeof', 'mw:Transclusion' );
$span->setAttribute( 'data-mw', json_encode( [ 'parts' => [ $wikitext ] ] ) );
return $span;
}
/**
* Check whether wikitext contains a user signature.
*
* @param string $wikitext
* @return bool
*/
public static function isWikitextSigned( string $wikitext ) : bool {
$wikitext = CommentUtils::htmlTrim( $wikitext );
// Contains ~~~~ (four tildes), but not ~~~~~ (five tildes), at the end.
return (bool)preg_match( '/([^~]|^)~~~~$/', $wikitext );
}
/**
* Check whether HTML node contains a user signature.
*
* @param DOMElement $container
* @return bool
*/
public static function isHtmlSigned( DOMElement $container ) : bool {
$xpath = new DOMXPath( $container->ownerDocument );
// Good enough?…
$matches = $xpath->query( './/span[@typeof="mw:Transclusion"][contains(@data-mw,"~~~~")]', $container );
if ( $matches->length === 0 ) {
return false;
}
$lastSig = $matches->item( $matches->length - 1 );
// Signature must be at the end of the comment - there must be no sibling following this node, or its parents
$node = $lastSig;
while ( $node ) {
// Skip over whitespace nodes
while (
$node->nextSibling &&
$node->nextSibling->nodeType === XML_TEXT_NODE &&
CommentUtils::htmlTrim( $node->nextSibling->nodeValue ) === ''
) {
$node = $node->nextSibling;
}
if ( $node->nextSibling ) {
return false;
}
$node = $node->parentNode;
}
return true;
}
/**
* Append a user signature to the comment in the container.
*
* @param DOMElement $container
*/
public static function appendSignature( DOMElement $container ) : void {
$doc = $container->ownerDocument;
// If the last node isn't a paragraph (e.g. it's a list created in visual mode), then
// add another paragraph to contain the signature.
if ( strtolower( $container->lastChild->nodeName ) !== 'p' ) {
$container->appendChild( $doc->createElement( 'p' ) );
}
// Sign the last line
// TODO: When we implement posting new topics, the leading space will create an indent-pre
$container->lastChild->appendChild(
self::createWikitextNode(
$doc,
wfMessage( 'discussiontools-signature-prefix' )->inContentLanguage()->text() . '~~~~'
)
);
}
/**
* Add a reply to a specific comment
*
* @param CommentItem $comment Comment being replied to
* @param DOMElement $container Container of comment DOM nodes
*/
public static function addReply( CommentItem $comment, DOMElement $container ) {
$newParsoidItem = null;
// Transfer comment DOM to Parsoid DOM
// Wrap every root node of the document in a new list item (dd/li).
// In wikitext mode every root node is a paragraph.
// In visual mode the editor takes care of preventing problematic nodes
// like <table> or <h2> from ever occurring in the comment.
while ( $container->childNodes->length ) {
if ( !$newParsoidItem ) {
$newParsoidItem = self::addListItem( $comment );
} else {
$newParsoidItem = self::addSiblingListItem( $newParsoidItem );
}
$newParsoidItem->appendChild( $container->firstChild );
}
}
/**
* Create a container of comment DOM nodes from wikitext
*
* @param CommentItem $comment Comment being replied to
* @param string $wikitext
*/
public static function addWikitextReply( $comment, $wikitext ) {
$doc = $comment->getRange()->endContainer->ownerDocument;
$container = $doc->createElement( 'div' );
$wikitext = self::sanitizeWikitextLinebreaks( $wikitext );
$lines = explode( "\n", $wikitext );
foreach ( $lines as $line ) {
$p = $doc->createElement( 'p' );
$p->appendChild( self::createWikitextNode( $doc, $line ) );
$container->appendChild( $p );
}
if ( !self::isWikitextSigned( $wikitext ) ) {
self::appendSignature( $container );
}
self::addReply( $comment, $container );
}
/**
* Create a container of comment DOM nodes from HTML
*
* @param CommentItem $comment Comment being replied to
* @param string $html
*/
public static function addHtmlReply( $comment, $html ) {
$doc = $comment->getRange()->endContainer->ownerDocument;
$container = $doc->createElement( 'div' );
DOMCompat::setInnerHTML( $container, $html );
// Remove empty lines
// This should really be anything that serializes to empty string in wikitext,
// (e.g. <h2></h2>) but this will catch most cases
// Create a non-live child node list, so we don't have to worry about it changing
// as nodes are removed.
$childNodeList = iterator_to_array( $container->childNodes );
foreach ( $childNodeList as $node ) {
if (
strtolower( $node->nodeName ) === 'p' &&
CommentUtils::htmlTrim( DOMCompat::getInnerHTML( $node ) ) === ''
) {
$container->removeChild( $node );
}
}
if ( !self::isHtmlSigned( $container ) ) {
self::appendSignature( $container );
}
self::addReply( $comment, $container );
}
}