Cleanup for r53518 (subpage support for edit comments)

[lhc/web/wiklou.git] / includes / Linker.php

<?php
/**
 * Split off some of the internal bits from Skin.php. These functions are used
 * for primarily page content: links, embedded images, table of contents. Links
 * are also used in the skin. For the moment, Skin is a descendent class of
 * Linker.  In the future, it should probably be further split so that every
 * other bit of the wiki doesn't have to go loading up Skin to get at it.
 *
 * @ingroup Skins
 */
class Linker {

        /**
         * Flags for userToolLinks()
         */
        const TOOL_LINKS_NOBLOCK = 1;

        function __construct() {}

        /**
         * Get the appropriate HTML attributes to add to the "a" element of an ex-
         * ternal link, as created by [wikisyntax].
         *
         * @param string $class  The contents of the class attribute; if an empty
         *   string is passed, which is the default value, defaults to 'external'.
         */
        function getExternalLinkAttributes( $class = 'external' ) {
                return $this->getLinkAttributesInternal( '', $class );
        }

        /**
         * Get the appropriate HTML attributes to add to the "a" element of an in-
         * terwiki link.
         *
         * @param string $title  The title text for the link, URL-encoded (???) but
         *   not HTML-escaped
         * @param string $unused Unused
         * @param string $class  The contents of the class attribute; if an empty
         *   string is passed, which is the default value, defaults to 'external'.
         */
        function getInterwikiLinkAttributes( $title, $unused = null, $class = 'external' ) {
                global $wgContLang;

                # FIXME: We have a whole bunch of handling here that doesn't happen in
                # getExternalLinkAttributes, why?
                $title = urldecode( $title );
                $title = $wgContLang->checkTitleEncoding( $title );
                $title = preg_replace( '/[\\x00-\\x1f]/', ' ', $title );

                return $this->getLinkAttributesInternal( $title, $class );
        }

        /**
         * Get the appropriate HTML attributes to add to the "a" element of an in-
         * ternal link.
         *
         * @param string $title  The title text for the link, URL-encoded (???) but
         *   not HTML-escaped
         * @param string $unused Unused
         * @param string $class  The contents of the class attribute, default none
         */
        function getInternalLinkAttributes( $title, $unused = null, $class='' ) {
                $title = urldecode( $title );
                $title = str_replace( '_', ' ', $title );
                return $this->getLinkAttributesInternal( $title, $class );
        }

        /**
         * Get the appropriate HTML attributes to add to the "a" element of an in-
         * ternal link, given the Title object for the page we want to link to.
         *
         * @param Title  $nt     The Title object
         * @param string $unused Unused
         * @param string $class  The contents of the class attribute, default none
         * @param mixed  $title  Optional (unescaped) string to use in the title
         *   attribute; if false, default to the name of the page we're linking to
         */
        function getInternalLinkAttributesObj( $nt, $unused = null, $class = '', $title = false ) {
                if( $title === false ) {
                        $title = $nt->getPrefixedText();
                }
                return $this->getLinkAttributesInternal( $title, $class );
        }

        /**
         * Common code for getLinkAttributesX functions
         */
        private function getLinkAttributesInternal( $title, $class ) {
                $title = htmlspecialchars( $title );
                $class = htmlspecialchars( $class );
                $r = '';
                if ( $class != '' ) {
                        $r .= " class=\"$class\"";
                }
                if ( $title != '') {
                        $r .= " title=\"$title\"";
                }
                return $r;
        }

        /**
         * Return the CSS colour of a known link
         *
         * @param Title $t
         * @param integer $threshold user defined threshold
         * @return string CSS class
         */
        function getLinkColour( $t, $threshold ) {
                $colour = '';
                if ( $t->isRedirect() ) {
                        # Page is a redirect
                        $colour = 'mw-redirect';
                } elseif ( $threshold > 0 && 
                           $t->exists() && $t->getLength() < $threshold &&
                           MWNamespace::isContent( $t->getNamespace() ) ) {
                        # Page is a stub
                        $colour = 'stub';
                }
                return $colour;
        }

        /**
         * This function returns an HTML link to the given target.  It serves a few
         * purposes:
         *   1) If $target is a Title, the correct URL to link to will be figured
         *      out automatically.
         *   2) It automatically adds the usual classes for various types of link
         *      targets: "new" for red links, "stub" for short articles, etc.
         *   3) It escapes all attribute values safely so there's no risk of XSS.
         *   4) It provides a default tooltip if the target is a Title (the page
         *      name of the target).
         * link() replaces the old functions in the makeLink() family.
         *
         * @param $target        Title  Can currently only be a Title, but this may
         *   change to support Images, literal URLs, etc.
         * @param $text          string The HTML contents of the <a> element, i.e.,
         *   the link text.  This is raw HTML and will not be escaped.  If null,
         *   defaults to the prefixed text of the Title; or if the Title is just a
         *   fragment, the contents of the fragment.
         * @param $customAttribs array  A key => value array of extra HTML attri-
         *   butes, such as title and class.  (href is ignored.)  Classes will be
         *   merged with the default classes, while other attributes will replace
         *   default attributes.  All passed attribute values will be HTML-escaped.
         *   A false attribute value means to suppress that attribute.
         * @param $query         array  The query string to append to the URL
         *   you're linking to, in key => value array form.  Query keys and values
         *   will be URL-encoded.
         * @param $options       mixed  String or array of strings:
         *     'known': Page is known to exist, so don't check if it does.
         *     'broken': Page is known not to exist, so don't check if it does.
         *     'noclasses': Don't add any classes automatically (includes "new",
         *       "stub", "mw-redirect", "extiw").  Only use the class attribute
         *       provided, if any, so you get a simple blue link with no funny i-
         *       cons.
         *     'forcearticlepath': Use the article path always, even with a querystring.
         *       Has compatibility issues on some setups, so avoid wherever possible.
         * @return string HTML <a> attribute
         */
        public function link( $target, $text = null, $customAttribs = array(), $query = array(), $options = array() ) {
                wfProfileIn( __METHOD__ );
                if( !$target instanceof Title ) {
                        return "<!-- ERROR -->$text";
                }
                $options = (array)$options;

                $ret = null;
                if( !wfRunHooks( 'LinkBegin', array( $this, $target, &$text,
                &$customAttribs, &$query, &$options, &$ret ) ) ) {
                        wfProfileOut( __METHOD__ );
                        return $ret;
                }

                # Normalize the Title if it's a special page
                $target = $this->normaliseSpecialPage( $target );

                # If we don't know whether the page exists, let's find out.
                wfProfileIn( __METHOD__ . '-checkPageExistence' );
                if( !in_array( 'known', $options ) and !in_array( 'broken', $options ) ) {
                        if( $target->isKnown() ) {
                                $options []= 'known';
                        } else {
                                $options []= 'broken';
                        }
                }
                wfProfileOut( __METHOD__ . '-checkPageExistence' );

                $oldquery = array();
                if( in_array( "forcearticlepath", $options ) && $query ){
                        $oldquery = $query;
                        $query = array();
                }

                # Note: we want the href attribute first, for prettiness.
                $attribs = array( 'href' => $this->linkUrl( $target, $query, $options ) );
                if( in_array( 'forcearticlepath', $options ) && $oldquery ){
                        $attribs['href'] = wfAppendQuery( $attribs['href'], wfArrayToCgi( $oldquery ) );
                }

                $attribs = array_merge(
                        $attribs,
                        $this->linkAttribs( $target, $customAttribs, $options )
                );
                if( is_null( $text ) ) {
                        $text = $this->linkText( $target );
                }

                $ret = null;
                if( wfRunHooks( 'LinkEnd', array( $this, $target, $options, &$text, &$attribs, &$ret ) ) ) {
                        $ret = Xml::openElement( 'a', $attribs ) . $text . Xml::closeElement( 'a' );
                }

                wfProfileOut( __METHOD__ );
                return $ret;
        }

        /**
         * Identical to link(), except $options defaults to 'known'.
         */
        public function linkKnown( $target, $text = null, $customAttribs = array(), $query = array(), $options = 'known' ) {
                return $this->link( $target, $text, $customAttribs, $query, $options );
        }

        private function linkUrl( $target, $query, $options ) {
                wfProfileIn( __METHOD__ );
                # We don't want to include fragments for broken links, because they
                # generally make no sense.
                if( in_array( 'broken', $options ) and $target->mFragment !== '' ) {
                        $target = clone $target;
                        $target->mFragment = '';
                }

                # If it's a broken link, add the appropriate query pieces, unless
                # there's already an action specified, or unless 'edit' makes no sense
                # (i.e., for a nonexistent special page).
                if( in_array( 'broken', $options ) and empty( $query['action'] )
                and $target->getNamespace() != NS_SPECIAL ) {
                        $query['action'] = 'edit';
                        $query['redlink'] = '1';
                }
                $ret = $target->getLinkUrl( $query );
                wfProfileOut( __METHOD__ );
                return $ret;
        }

        private function linkAttribs( $target, $attribs, $options ) {
                wfProfileIn( __METHOD__ );
                global $wgUser;
                $defaults = array();

                if( !in_array( 'noclasses', $options ) ) {
                        wfProfileIn( __METHOD__ . '-getClasses' );
                        # Now build the classes.
                        $classes = array();

                        if( in_array( 'broken', $options ) ) {
                                $classes[] = 'new';
                        }

                        if( $target->isExternal() ) {
                                $classes[] = 'extiw';
                        }

                        # Note that redirects never count as stubs here.
                        if ( !in_array( 'broken', $options ) && $target->isRedirect() ) {
                                $classes[] = 'mw-redirect';
                        } elseif( $target->isContentPage() ) {
                                # Check for stub.
                                $threshold = $wgUser->getOption( 'stubthreshold' );
                                if( $threshold > 0 and $target->exists() and $target->getLength() < $threshold ) {
                                        $classes[] = 'stub';
                                }
                        }
                        if( $classes != array() ) {
                                $defaults['class'] = implode( ' ', $classes );
                        }
                        wfProfileOut( __METHOD__ . '-getClasses' );
                }

                # Get a default title attribute.
                if( $target->getPrefixedText() == '' ) {
                        # A link like [[#Foo]].  This used to mean an empty title
                        # attribute, but that's silly.  Just don't output a title.
                } elseif( in_array( 'known', $options ) ) {
                        $defaults['title'] = $target->getPrefixedText();
                } else {
                        $defaults['title'] = wfMsg( 'red-link-title', $target->getPrefixedText() );
                }

                # Finally, merge the custom attribs with the default ones, and iterate
                # over that, deleting all "false" attributes.
                $ret = array();
                $merged = Sanitizer::mergeAttributes( $defaults, $attribs );
                foreach( $merged as $key => $val ) {
                        # A false value suppresses the attribute, and we don't want the
                        # href attribute to be overridden.
                        if( $key != 'href' and $val !== false ) {
                                $ret[$key] = $val;
                        }
                }
                wfProfileOut( __METHOD__ );
                return $ret;
        }

        private function linkText( $target ) {
                # We might be passed a non-Title by make*LinkObj().  Fail gracefully.
                if( !$target instanceof Title ) {
                        return '';
                }

                # If the target is just a fragment, with no title, we return the frag-
                # ment text.  Otherwise, we return the title text itself.
                if( $target->getPrefixedText() === '' and $target->getFragment() !== '' ) {
                        return htmlspecialchars( $target->getFragment() );
                }
                return htmlspecialchars( $target->getPrefixedText() );
        }

        /**
         * Generate either a normal exists-style link or a stub link, depending
         * on the given page size.
         *
         * @param $size Integer
         * @param $nt Title object.
         * @param $text String
         * @param $query String
         * @param $trail String
         * @param $prefix String
         * @return string HTML of link
         */
        function makeSizeLinkObj( $size, $nt, $text = '', $query = '', $trail = '', $prefix = '' ) {
                global $wgUser;
                $threshold = intval( $wgUser->getOption( 'stubthreshold' ) );
                $colour = ( $size < $threshold ) ? 'stub' : '';
                // FIXME: replace deprecated makeColouredLinkObj by link()
                return $this->makeColouredLinkObj( $nt, $colour, $text, $query, $trail, $prefix );
        }

        /**
         * Make appropriate markup for a link to the current article. This is currently rendered
         * as the bold link text. The calling sequence is the same as the other make*LinkObj functions,
         * despite $query not being used.
         */
        function makeSelfLinkObj( $nt, $text = '', $query = '', $trail = '', $prefix = '' ) {
                if ( '' == $text ) {
                        $text = htmlspecialchars( $nt->getPrefixedText() );
                }
                list( $inside, $trail ) = Linker::splitTrail( $trail );
                return "<strong class=\"selflink\">{$prefix}{$text}{$inside}</strong>{$trail}";
        }

        function normaliseSpecialPage( Title $title ) {
                if ( $title->getNamespace() == NS_SPECIAL ) {
                        list( $name, $subpage ) = SpecialPage::resolveAliasWithSubpage( $title->getDBkey() );
                        if ( !$name ) return $title;
                        $ret = SpecialPage::getTitleFor( $name, $subpage );
                        $ret->mFragment = $title->getFragment();
                        return $ret;
                } else {
                        return $title;
                }
        }

        /** @todo document */
        function fnamePart( $url ) {
                $basename = strrchr( $url, '/' );
                if ( false === $basename ) {
                        $basename = $url;
                } else {
                        $basename = substr( $basename, 1 );
                }
                return $basename;
        }

        /** @todo document */
        function makeExternalImage( $url, $alt = '' ) {
                if ( '' == $alt ) {
                        $alt = $this->fnamePart( $url );
                }
                $img = '';
                $success = wfRunHooks('LinkerMakeExternalImage', array( &$url, &$alt, &$img ) );
                if(!$success) {
                        wfDebug("Hook LinkerMakeExternalImage changed the output of external image with url {$url} and alt text {$alt} to {$img}\n", true);
                        return $img;
                }
                return Xml::element( 'img',
                        array(
                                'src' => $url,
                                'alt' => $alt ) );
        }

        /**
         * Given parameters derived from [[Image:Foo|options...]], generate the
         * HTML that that syntax inserts in the page.
         *
         * @param Title $title Title object
         * @param File $file File object, or false if it doesn't exist
         *
         * @param array $frameParams Associative array of parameters external to the media handler.
         *     Boolean parameters are indicated by presence or absence, the value is arbitrary and
         *     will often be false.
         *          thumbnail       If present, downscale and frame
         *          manualthumb     Image name to use as a thumbnail, instead of automatic scaling
         *          framed          Shows image in original size in a frame
         *          frameless       Downscale but don't frame
         *          upright         If present, tweak default sizes for portrait orientation
         *          upright_factor  Fudge factor for "upright" tweak (default 0.75)
         *          border          If present, show a border around the image
         *          align           Horizontal alignment (left, right, center, none)
         *          valign          Vertical alignment (baseline, sub, super, top, text-top, middle,
         *                          bottom, text-bottom)
         *          alt             Alternate text for image (i.e. alt attribute). Plain text.
         *          caption         HTML for image caption.
         *          link-url        URL to link to
         *          link-title      Title object to link to
         *          no-link         Boolean, suppress description link
         *
         * @param array $handlerParams Associative array of media handler parameters, to be passed
         *       to transform(). Typical keys are "width" and "page".
         * @param string $time, timestamp of the file, set as false for current
         * @param string $query, query params for desc url
         * @return string HTML for an image, with links, wrappers, etc.
         */
        function makeImageLink2( Title $title, $file, $frameParams = array(), $handlerParams = array(), $time = false, $query = "" ) {
                $res = null;
                if( !wfRunHooks( 'ImageBeforeProduceHTML', array( &$this, &$title,
                &$file, &$frameParams, &$handlerParams, &$time, &$res ) ) ) {
                        return $res;
                }

                global $wgContLang, $wgUser, $wgThumbLimits, $wgThumbUpright;
                if ( $file && !$file->allowInlineDisplay() ) {
                        wfDebug( __METHOD__.': '.$title->getPrefixedDBkey()." does not allow inline display\n" );
                        return $this->link( $title );
                }

                // Shortcuts
                $fp =& $frameParams;
                $hp =& $handlerParams;

                // Clean up parameters
                $page = isset( $hp['page'] ) ? $hp['page'] : false;
                if ( !isset( $fp['align'] ) ) $fp['align'] = '';
                if ( !isset( $fp['alt'] ) ) $fp['alt'] = '';
                if ( !isset( $fp['title'] ) ) $fp['title'] = '';

                $prefix = $postfix = '';

                if ( 'center' == $fp['align'] ) {
                        $prefix  = '<div class="center">';
                        $postfix = '</div>';
                        $fp['align']   = 'none';
                }
                if ( $file && !isset( $hp['width'] ) ) {
                        $hp['width'] = $file->getWidth( $page );

                        if( isset( $fp['thumbnail'] ) || isset( $fp['framed'] ) || isset( $fp['frameless'] ) || !$hp['width'] ) {
                                $wopt = $wgUser->getOption( 'thumbsize' );

                                if( !isset( $wgThumbLimits[$wopt] ) ) {
                                         $wopt = User::getDefaultOption( 'thumbsize' );
                                }

                                // Reduce width for upright images when parameter 'upright' is used
                                if ( isset( $fp['upright'] ) && $fp['upright'] == 0 ) {
                                        $fp['upright'] = $wgThumbUpright;
                                }
                                // Use width which is smaller: real image width or user preference width
                                // For caching health: If width scaled down due to upright parameter, round to full __0 pixel to avoid the creation of a lot of odd thumbs
                                $prefWidth = isset( $fp['upright'] ) ?
                                        round( $wgThumbLimits[$wopt] * $fp['upright'], -1 ) :
                                        $wgThumbLimits[$wopt];
                                if ( $hp['width'] <= 0 || $prefWidth < $hp['width'] ) {
                                        $hp['width'] = $prefWidth;
                                }
                        }
                }

                if ( isset( $fp['thumbnail'] ) || isset( $fp['manualthumb'] ) || isset( $fp['framed'] ) ) {
                        # Create a thumbnail. Alignment depends on language
                        # writing direction, # right aligned for left-to-right-
                        # languages ("Western languages"), left-aligned
                        # for right-to-left-languages ("Semitic languages")
                        #
                        # If  thumbnail width has not been provided, it is set
                        # to the default user option as specified in Language*.php
                        if ( $fp['align'] == '' ) {
                                $fp['align'] = $wgContLang->isRTL() ? 'left' : 'right';
                        }
                        return $prefix.$this->makeThumbLink2( $title, $file, $fp, $hp, $time, $query ).$postfix;
                }

                if ( $file && isset( $fp['frameless'] ) ) {
                        $srcWidth = $file->getWidth( $page );
                        # For "frameless" option: do not present an image bigger than the source (for bitmap-style images)
                        # This is the same behaviour as the "thumb" option does it already.
                        if ( $srcWidth && !$file->mustRender() && $hp['width'] > $srcWidth ) {
                                $hp['width'] = $srcWidth;
                        }
                }

                if ( $file && $hp['width'] ) {
                        # Create a resized image, without the additional thumbnail features
                        $thumb = $file->transform( $hp );
                } else {
                        $thumb = false;
                }

                if ( !$thumb ) {
                        $s = $this->makeBrokenImageLinkObj( $title, '', '', '', '', $time==true );
                } else {
                        $params = array(
                                'alt' => $fp['alt'],
                                'title' => $fp['title'],
                                'valign' => isset( $fp['valign'] ) ? $fp['valign'] : false ,
                                'img-class' => isset( $fp['border'] ) ? 'thumbborder' : false );
                        if ( !empty( $fp['link-url'] ) ) {
                                $params['custom-url-link'] = $fp['link-url'];
                        } elseif ( !empty( $fp['link-title'] ) ) {
                                $params['custom-title-link'] = $fp['link-title'];
                        } elseif ( !empty( $fp['no-link'] ) ) {
                                // No link
                        } else {
                                $params['desc-link'] = true;
                                $params['desc-query'] = $query;
                        }

                        $s = $thumb->toHtml( $params );
                }
                if ( '' != $fp['align'] ) {
                        $s = "<div class=\"float{$fp['align']}\">{$s}</div>";
                }
                return str_replace("\n", ' ',$prefix.$s.$postfix);
        }

        /**
         * Make HTML for a thumbnail including image, border and caption
         * @param Title $title
         * @param File $file File object or false if it doesn't exist
         */
        function makeThumbLinkObj( Title $title, $file, $label = '', $alt, $align = 'right', $params = array(), $framed=false , $manualthumb = "" ) {
                $frameParams = array(
                        'alt' => $alt,
                        'caption' => $label,
                        'align' => $align
                );
                if ( $framed ) $frameParams['framed'] = true;
                if ( $manualthumb ) $frameParams['manualthumb'] = $manualthumb;
                return $this->makeThumbLink2( $title, $file, $frameParams, $params );
        }

        function makeThumbLink2( Title $title, $file, $frameParams = array(), $handlerParams = array(), $time = false, $query = "" ) {
                global $wgStylePath, $wgContLang;
                $exists = $file && $file->exists();

                # Shortcuts
                $fp =& $frameParams;
                $hp =& $handlerParams;

                $page = isset( $hp['page'] ) ? $hp['page'] : false;
                if ( !isset( $fp['align'] ) ) $fp['align'] = 'right';
                if ( !isset( $fp['alt'] ) ) $fp['alt'] = '';
                if ( !isset( $fp['title'] ) ) $fp['title'] = '';
                if ( !isset( $fp['caption'] ) ) $fp['caption'] = '';

                if ( empty( $hp['width'] ) ) {
                        // Reduce width for upright images when parameter 'upright' is used
                        $hp['width'] = isset( $fp['upright'] ) ? 130 : 180;
                }
                $thumb = false;

                if ( !$exists ) {
                        $outerWidth = $hp['width'] + 2;
                } else {
                        if ( isset( $fp['manualthumb'] ) ) {
                                # Use manually specified thumbnail
                                $manual_title = Title::makeTitleSafe( NS_FILE, $fp['manualthumb'] );
                                if( $manual_title ) {
                                        $manual_img = wfFindFile( $manual_title );
                                        if ( $manual_img ) {
                                                $thumb = $manual_img->getUnscaledThumb();
                                        } else {
                                                $exists = false;
                                        }
                                }
                        } elseif ( isset( $fp['framed'] ) ) {
                                // Use image dimensions, don't scale
                                $thumb = $file->getUnscaledThumb( $page );
                        } else {
                                # Do not present an image bigger than the source, for bitmap-style images
                                # This is a hack to maintain compatibility with arbitrary pre-1.10 behaviour
                                $srcWidth = $file->getWidth( $page );
                                if ( $srcWidth && !$file->mustRender() && $hp['width'] > $srcWidth ) {
                                        $hp['width'] = $srcWidth;
                                }
                                $thumb = $file->transform( $hp );
                        }

                        if ( $thumb ) {
                                $outerWidth = $thumb->getWidth() + 2;
                        } else {
                                $outerWidth = $hp['width'] + 2;
                        }
                }

                # ThumbnailImage::toHtml() already adds page= onto the end of DjVu URLs
                # So we don't need to pass it here in $query. However, the URL for the
                # zoom icon still needs it, so we make a unique query for it. See bug 14771
                $url = $title->getLocalURL( $query );
                if( $page ) { 
                        $url = wfAppendQuery( $url, 'page=' . urlencode( $page ) );
                }

                $more = htmlspecialchars( wfMsg( 'thumbnail-more' ) );

                $s = "<div class=\"thumb t{$fp['align']}\"><div class=\"thumbinner\" style=\"width:{$outerWidth}px;\">";
                if( !$exists ) {
                        $s .= $this->makeBrokenImageLinkObj( $title, '', '', '', '', $time==true );
                        $zoomicon = '';
                } elseif ( !$thumb ) {
                        $s .= htmlspecialchars( wfMsg( 'thumbnail_error', '' ) );
                        $zoomicon = '';
                } else {
                        $s .= $thumb->toHtml( array(
                                'alt' => $fp['alt'],
                                'title' => $fp['title'],
                                'img-class' => 'thumbimage',
                                'desc-link' => true,
                                'desc-query' => $query ) );
                        if ( isset( $fp['framed'] ) ) {
                                $zoomicon="";
                        } else {
                                $zoomicon =  '<div class="magnify">'.
                                        '<a href="'.$url.'" class="internal" title="'.$more.'">'.
                                        '<img src="'.$wgStylePath.'/common/images/magnify-clip.png" ' .
                                        'width="15" height="11" alt="" /></a></div>';
                        }
                }
                $s .= '  <div class="thumbcaption">'.$zoomicon.$fp['caption']."</div></div></div>";
                return str_replace("\n", ' ', $s);
        }

        /**
         * Make a "broken" link to an image
         *
         * @param Title $title Image title
         * @param string $text Link label
         * @param string $query Query string
         * @param string $trail Link trail
         * @param string $prefix Link prefix
         * @param bool $time, a file of a certain timestamp was requested
         * @return string
         */
        public function makeBrokenImageLinkObj( $title, $text = '', $query = '', $trail = '', $prefix = '', $time = false ) {
                global $wgEnableUploads;
                if( $title instanceof Title ) {
                        wfProfileIn( __METHOD__ );
                        $currentExists = $time ? ( wfFindFile( $title ) != false ) : false;
                        if( $wgEnableUploads && !$currentExists ) {
                                $upload = SpecialPage::getTitleFor( 'Upload' );
                                if( $text == '' )
                                        $text = htmlspecialchars( $title->getPrefixedText() );
                                $redir = RepoGroup::singleton()->getLocalRepo()->checkRedirect( $title );
                                if( $redir ) {
                                        return $this->makeKnownLinkObj( $title, $text, $query, $trail, $prefix );
                                }
                                $q = 'wpDestFile=' . $title->getPartialUrl();
                                if( $query != '' )
                                        $q .= '&' . $query;
                                list( $inside, $trail ) = self::splitTrail( $trail );
                                $style = $this->getInternalLinkAttributesObj( $title, $text, 'new' );
                                wfProfileOut( __METHOD__ );
                                return '<a href="' . $upload->escapeLocalUrl( $q ) . '"'
                                        . $style . '>' . $prefix . $text . $inside . '</a>' . $trail;
                        } else {
                                wfProfileOut( __METHOD__ );
                                return $this->makeKnownLinkObj( $title, $text, $query, $trail, $prefix );
                        }
                } else {
                        return "<!-- ERROR -->{$prefix}{$text}{$trail}";
                }
        }

        /**
         * Create a direct link to a given uploaded file.
         *
         * @param $title Title object.
         * @param $text String: pre-sanitized HTML
         * @param $time string: time image was created
         * @return string HTML
         *
         * @public
         * @todo Handle invalid or missing images better.
         */
        function makeMediaLinkObj( $title, $text = '', $time = false ) {
                if( is_null( $title ) ) {
                        ### HOTFIX. Instead of breaking, return empty string.
                        return $text;
                } else {
                        $img  = wfFindFile( $title, $time );
                        if( $img ) {
                                $url  = $img->getURL();
                                $class = 'internal';
                        } else {
                                $upload = SpecialPage::getTitleFor( 'Upload' );
                                $url = $upload->getLocalUrl( 'wpDestFile=' . urlencode( $title->getDBkey() ) );
                                $class = 'new';
                        }
                        $alt = htmlspecialchars( $title->getText() );
                        if( $text == '' ) {
                                $text = $alt;
                        }
                        $u = htmlspecialchars( $url );
                        return "<a href=\"{$u}\" class=\"$class\" title=\"{$alt}\">{$text}</a>";
                }
        }

        /** @todo document */
        function specialLink( $name, $key = '' ) {
                global $wgContLang;

                if ( '' == $key ) { $key = strtolower( $name ); }
                $pn = $wgContLang->ucfirst( $name );
                return $this->makeKnownLink( $wgContLang->specialPage( $pn ),
                  wfMsg( $key ) );
        }

        /**
         * Make an external link
         * @param String $url URL to link to
         * @param String $text text of link
         * @param boolean $escape Do we escape the link text?
         * @param String $linktype Type of external link. Gets added to the classes
         * @param array $attribs Array of extra attributes to <a>
         * 
         * @TODO! @FIXME! This is a really crappy implementation. $linktype and 
         * 'external' are mashed into the class attrib for the link (which is made
         * into a string). Then, if we've got additional params in $attribs, we 
         * add to it. People using this might want to change the classes (or other
         * default link attributes), but passing $attribsText is just messy. Would 
         * make a lot more sense to make put the classes into $attribs, let the 
         * hook play with them, *then* expand it all at once. 
         */
        function makeExternalLink( $url, $text, $escape = true, $linktype = '', $attribs = array() ) {
                $attribsText = $this->getExternalLinkAttributes( 'external ' . $linktype );
                $url = htmlspecialchars( $url );
                if( $escape ) {
                        $text = htmlspecialchars( $text );
                }
                $link = '';
                $success = wfRunHooks('LinkerMakeExternalLink', array( &$url, &$text, &$link, &$attribs, $linktype ) );
                if(!$success) {
                        wfDebug("Hook LinkerMakeExternalLink changed the output of link with url {$url} and text {$text} to {$link}\n", true);
                        return $link;
                }
                if ( $attribs ) {
                        $attribsText .= Xml::expandAttributes( $attribs );
                }
                return '<a href="'.$url.'"'.$attribsText.'>'.$text.'</a>';
        }

        /**
         * Make user link (or user contributions for unregistered users)
         * @param $userId   Integer: user id in database.
         * @param $userText String: user name in database
         * @return string HTML fragment
         * @private
         */
        function userLink( $userId, $userText ) {
                if( $userId == 0 ) {
                        $page = SpecialPage::getTitleFor( 'Contributions', $userText );
                } else {
                        $page = Title::makeTitle( NS_USER, $userText );
                }
                return $this->link( $page, htmlspecialchars( $userText ), array( 'class' => 'mw-userlink' ) );
        }

        /**
         * Generate standard user tool links (talk, contributions, block link, etc.)
         *
         * @param int $userId User identifier
         * @param string $userText User name or IP address
         * @param bool $redContribsWhenNoEdits Should the contributions link be red if the user has no edits?
         * @param int $flags Customisation flags (e.g. self::TOOL_LINKS_NOBLOCK)
         * @param int $edits, user edit count (optional, for performance)
         * @return string
         */
        public function userToolLinks( $userId, $userText, $redContribsWhenNoEdits = false, $flags = 0, $edits=null ) {
                global $wgUser, $wgDisableAnonTalk, $wgSysopUserBans, $wgLang;
                $talkable = !( $wgDisableAnonTalk && 0 == $userId );
                $blockable = ( $wgSysopUserBans || 0 == $userId ) && !$flags & self::TOOL_LINKS_NOBLOCK;

                $items = array();
                if( $talkable ) {
                        $items[] = $this->userTalkLink( $userId, $userText );
                }
                if( $userId ) {
                        // check if the user has an edit
                        $attribs = array();
                        if( $redContribsWhenNoEdits ) {
                                $count = !is_null($edits) ? $edits : User::edits( $userId );
                                if( $count == 0 ) {
                                        $attribs['class'] = 'new';
                                }
                        }
                        $contribsPage = SpecialPage::getTitleFor( 'Contributions', $userText );

                        $items[] = $this->link( $contribsPage, wfMsgHtml( 'contribslink' ), $attribs );
                }
                if( $blockable && $wgUser->isAllowed( 'block' ) ) {
                        $items[] = $this->blockLink( $userId, $userText );
                }

                if( $items ) {
                        return ' <span class="mw-usertoollinks">(' . $wgLang->pipeList( $items ) . ')</span>';
                } else {
                        return '';
                }
        }

        /**
         * Alias for userToolLinks( $userId, $userText, true );
         * @param int $userId User identifier
         * @param string $userText User name or IP address
         * @param int $edits, user edit count (optional, for performance)
         */
        public function userToolLinksRedContribs( $userId, $userText, $edits=null ) {
                return $this->userToolLinks( $userId, $userText, true, 0, $edits );
        }


        /**
         * @param $userId Integer: user id in database.
         * @param $userText String: user name in database.
         * @return string HTML fragment with user talk link
         * @private
         */
        function userTalkLink( $userId, $userText ) {
                $userTalkPage = Title::makeTitle( NS_USER_TALK, $userText );
                $userTalkLink = $this->link( $userTalkPage, wfMsgHtml( 'talkpagelinktext' ) );
                return $userTalkLink;
        }

        /**
         * @param $userId Integer: userid
         * @param $userText String: user name in database.
         * @return string HTML fragment with block link
         * @private
         */
        function blockLink( $userId, $userText ) {
                $blockPage = SpecialPage::getTitleFor( 'Blockip', $userText );
                $blockLink = $this->link( $blockPage, wfMsgHtml( 'blocklink' ) );
                return $blockLink;
        }

        /**
         * Generate a user link if the current user is allowed to view it
         * @param $rev Revision object.
         * @param $isPublic, bool, show only if all users can see it
         * @return string HTML
         */
        function revUserLink( $rev, $isPublic = false ) {
                if( $rev->isDeleted( Revision::DELETED_USER ) && $isPublic ) {
                        $link = wfMsgHtml( 'rev-deleted-user' );
                } else if( $rev->userCan( Revision::DELETED_USER ) ) {
                        $link = $this->userLink( $rev->getUser( Revision::FOR_THIS_USER ), 
                                $rev->getUserText( Revision::FOR_THIS_USER ) );
                } else {
                        $link = wfMsgHtml( 'rev-deleted-user' );
                }
                if( $rev->isDeleted( Revision::DELETED_USER ) ) {
                        return '<span class="history-deleted">' . $link . '</span>';
                }
                return $link;
        }

        /**
         * Generate a user tool link cluster if the current user is allowed to view it
         * @param $rev Revision object.
         * @param $isPublic, bool, show only if all users can see it
         * @return string HTML
         */
        function revUserTools( $rev, $isPublic = false ) {
                if( $rev->isDeleted( Revision::DELETED_USER ) && $isPublic ) {
                        $link = wfMsgHtml( 'rev-deleted-user' );
                } else if( $rev->userCan( Revision::DELETED_USER ) ) {
                        $userId = $rev->getUser( Revision::FOR_THIS_USER );
                        $userText = $rev->getUserText( Revision::FOR_THIS_USER ); 
                        $link = $this->userLink( $userId, $userText ) .
                                ' ' . $this->userToolLinks( $userId, $userText );
                } else {
                        $link = wfMsgHtml( 'rev-deleted-user' );
                }
                if( $rev->isDeleted( Revision::DELETED_USER ) ) {
                        return ' <span class="history-deleted">' . $link . '</span>';
                }
                return $link;
        }

        /**
         * This function is called by all recent changes variants, by the page history,
         * and by the user contributions list. It is responsible for formatting edit
         * comments. It escapes any HTML in the comment, but adds some CSS to format
         * auto-generated comments (from section editing) and formats [[wikilinks]].
         *
         * @author Erik Moeller <moeller@scireview.de>
         *
         * Note: there's not always a title to pass to this function.
         * Since you can't set a default parameter for a reference, I've turned it
         * temporarily to a value pass. Should be adjusted further. --brion
         *
         * @param string $comment
         * @param mixed $title Title object (to generate link to the section in autocomment) or null
         * @param bool $local Whether section links should refer to local page
         */
        function formatComment($comment, $title = NULL, $local = false) {
                wfProfileIn( __METHOD__ );

                # Sanitize text a bit:
                $comment = str_replace( "\n", " ", $comment );
                # Allow HTML entities (for bug 13815)
                $comment = Sanitizer::escapeHtmlAllowEntities( $comment );

                # Render autocomments and make links:
                $comment = $this->formatAutoComments( $comment, $title, $local );
                $comment = $this->formatLinksInComment( $comment, $title, $local );

                wfProfileOut( __METHOD__ );
                return $comment;
        }

        /**
         * The pattern for autogen comments is / * foo * /, which makes for
         * some nasty regex.
         * We look for all comments, match any text before and after the comment,
         * add a separator where needed and format the comment itself with CSS
         * Called by Linker::formatComment.
         *
         * @param string $comment Comment text
         * @param object $title An optional title object used to links to sections
         * @return string $comment formatted comment
         *
         * @todo Document the $local parameter.
         */
        private function formatAutocomments( $comment, $title = null, $local = false ) {
                // Bah!
                $this->autocommentTitle = $title;
                $this->autocommentLocal = $local;
                $comment = preg_replace_callback(
                        '!(.*)/\*\s*(.*?)\s*\*/(.*)!',
                        array( $this, 'formatAutocommentsCallback' ),
                        $comment );
                unset( $this->autocommentTitle );
                unset( $this->autocommentLocal );
                return $comment;
        }
        
        private function formatAutocommentsCallback( $match ) {
                $title = $this->autocommentTitle;
                $local = $this->autocommentLocal;
                
                $pre=$match[1];
                $auto=$match[2];
                $post=$match[3];
                $link='';
                if( $title ) {
                        $section = $auto;

                        # Generate a valid anchor name from the section title.
                        # Hackish, but should generally work - we strip wiki
                        # syntax, including the magic [[: that is used to
                        # "link rather than show" in case of images and
                        # interlanguage links.
                        $section = str_replace( '[[:', '', $section );
                        $section = str_replace( '[[', '', $section );
                        $section = str_replace( ']]', '', $section );
                        if ( $local ) {
                                $sectionTitle = Title::newFromText( '#' . $section );
                        } else {
                                $sectionTitle = Title::makeTitleSafe( $title->getNamespace(), 
                                        $title->getDBkey(), $section );
                        }
                        if ( $sectionTitle ) {
                                $link = $this->link( $sectionTitle,
                                        htmlspecialchars( wfMsgForContent( 'sectionlink' ) ), array(), array(),
                                        'noclasses' );
                        } else {
                                $link = '';
                        }
                }
                $auto = "$link$auto";
                if( $pre ) {
                        # written summary $presep autocomment (summary /* section */)
                        $auto = wfMsgExt( 'autocomment-prefix', array( 'escapenoentities', 'content' ) ) . $auto;
                }
                if( $post ) {
                        # autocomment $postsep written summary (/* section */ summary)
                        $auto .= wfMsgExt( 'colon-separator', array( 'escapenoentities', 'content' ) );
                }
                $auto = '<span class="autocomment">' . $auto . '</span>';
                $comment = $pre . $auto . $post;
                return $comment;
        }

        /**
         * Formats wiki links and media links in text; all other wiki formatting
         * is ignored
         *
         * @fixme doesn't handle sub-links as in image thumb texts like the main parser
         * @param string $comment Text to format links in
         * @return string
         */
        public function formatLinksInComment( $comment, $title = null, $local = false ) {
                $this->commentContextTitle = $title;
                $this->commentLocal = $local;
                # Borrowed from Parser::replaceInternalLinks2
                $parts = StringUtils::explode( '[[', ' ' . $comment );
                $start = $parts->current();
                $parts->next();
                $line = $parts->current();
                $html = substr( $start, 1 );
                for ( ; $line !== false && $line !== null ; $parts->next(), $line = $parts->current() ) {                       
                        $linked = preg_replace_callback(
                                '/^:?(.*?)(\|(.*?))*\]\]([^[]*)/',
                                array( $this, 'formatLinksInCommentCallback' ),
                                $line, -1, $count );
                        if( !$count ) { // No valid link found, put the brackets back
                                $linked = '[[' . $linked;
                        }
                        $html .= $linked;
                }
                unset( $this->commentContextTitle );
                unset( $this->commentLocal );
                return $html;
        }

        protected function formatLinksInCommentCallback( $match ) {
                global $wgContLang;

                $medians = '(?:' . preg_quote( MWNamespace::getCanonicalName( NS_MEDIA ), '/' ) . '|';
                $medians .= preg_quote( $wgContLang->getNsText( NS_MEDIA ), '/' ) . '):';

                $comment = $match[0];

                # fix up urlencoded title texts (copied from Parser::replaceInternalLinks)
                if( strpos( $match[1], '%' ) !== false ) {
                        $match[1] = str_replace( array('<', '>'), array('&lt;', '&gt;'), urldecode($match[1]) );
                }

                # Handle link renaming [[foo|text]] will show link as "text"
                if( "" != $match[3] ) {
                        $text = $match[3];
                } else {
                        $text = $match[1];
                }
                $submatch = array();
                $thelink = null;
                if( preg_match( '/^' . $medians . '(.*)$/i', $match[1], $submatch ) ) {
                        # Media link; trail not supported.
                        $linkRegexp = '/^(.*?)\]\]/';
                        $title = Title::makeTitleSafe( NS_FILE, $submatch[1] );
                        $thelink = $this->makeMediaLinkObj( $title, $text );
                } else {
                        # Other kind of link
                        if( preg_match( $wgContLang->linkTrail(), $match[4], $submatch ) ) {
                                $trail = $submatch[1];
                        } else {
                                $trail = "";
                        }
                        $linkRegexp = '/^(.*?)\]\]' . preg_quote( $trail, '/' ) . '/';
                        if (isset($match[1][0]) && $match[1][0] == ':')
                                $match[1] = substr($match[1], 1);
                        list( $inside, $trail ) = Linker::splitTrail( $trail );
                        
                        $linkText = $text;
                        $linkTarget = Linker::normalizeSubpageLink( $this->commentContextTitle,
                                $match[1], $linkText );
                        
                        $target = Title::newFromText( $linkTarget );
                        if( $target ) {
                                if( $target->getText() == '' && !$this->commentLocal && $this->commentContextTitle ) {
                                        $newTarget = clone( $this->commentContextTitle );
                                        $newTarget->setFragment( '#' . $target->getFragment() );
                                        $target = $newTarget;
                                }
                                $thelink = $this->link(
                                        $target,
                                        $linkText . $inside
                                ) . $trail;
                        }
                }
                if( $thelink ) {
                        // If the link is still valid, go ahead and replace it in!
                        $comment = preg_replace( $linkRegexp, StringUtils::escapeRegexReplacement( $thelink ), $comment, 1 );
                }

                return $comment;
        }
        
        static function normalizeSubpageLink( $contextTitle, $target, &$text ) {
                # Valid link forms:
                # Foobar -- normal
                # :Foobar -- override special treatment of prefix (images, language links)
                # /Foobar -- convert to CurrentPage/Foobar
                # /Foobar/ -- convert to CurrentPage/Foobar, strip the initial / from text
                # ../ -- convert to CurrentPage, from CurrentPage/CurrentSubPage
                # ../Foobar -- convert to CurrentPage/Foobar, from CurrentPage/CurrentSubPage

                wfProfileIn( __METHOD__ );
                $ret = $target; # default return value is no change

                # Some namespaces don't allow subpages,
                # so only perform processing if subpages are allowed
                if( $contextTitle && MWNamespace::hasSubpages( $contextTitle->getNamespace() ) ) {
                        $hash = strpos( $target, '#' );
                        if( $hash !== false ) {
                                $suffix = substr( $target, $hash );
                                $target = substr( $target, 0, $hash );
                        } else {
                                $suffix = '';
                        }
                        # bug 7425
                        $target = trim( $target );
                        # Look at the first character
                        if( $target != '' && $target{0} === '/' ) {
                                # / at end means we don't want the slash to be shown
                                $m = array();
                                $trailingSlashes = preg_match_all( '%(/+)$%', $target, $m );
                                if( $trailingSlashes ) {
                                        $noslash = $target = substr( $target, 1, -strlen($m[0][0]) );
                                } else {
                                        $noslash = substr( $target, 1 );
                                }

                                $ret = $contextTitle->getPrefixedText(). '/' . trim($noslash) . $suffix;
                                if( '' === $text ) {
                                        $text = $target . $suffix;
                                } # this might be changed for ugliness reasons
                        } else {
                                # check for .. subpage backlinks
                                $dotdotcount = 0;
                                $nodotdot = $target;
                                while( strncmp( $nodotdot, "../", 3 ) == 0 ) {
                                        ++$dotdotcount;
                                        $nodotdot = substr( $nodotdot, 3 );
                                }
                                if($dotdotcount > 0) {
                                        $exploded = explode( '/', $contextTitle->GetPrefixedText() );
                                        if( count( $exploded ) > $dotdotcount ) { # not allowed to go below top level page
                                                $ret = implode( '/', array_slice( $exploded, 0, -$dotdotcount ) );
                                                # / at the end means don't show full path
                                                if( substr( $nodotdot, -1, 1 ) === '/' ) {
                                                        $nodotdot = substr( $nodotdot, 0, -1 );
                                                        if( '' === $text ) {
                                                                $text = $nodotdot . $suffix;
                                                        }
                                                }
                                                $nodotdot = trim( $nodotdot );
                                                if( $nodotdot != '' ) {
                                                        $ret .= '/' . $nodotdot;
                                                }
                                                $ret .= $suffix;
                                        }
                                }
                        }
                }

                wfProfileOut( __METHOD__ );
                return $ret;
        }

        /**
         * Wrap a comment in standard punctuation and formatting if
         * it's non-empty, otherwise return empty string.
         *
         * @param string $comment
         * @param mixed $title Title object (to generate link to section in autocomment) or null
         * @param bool $local Whether section links should refer to local page
         *
         * @return string
         */
        function commentBlock( $comment, $title = NULL, $local = false ) {
                // '*' used to be the comment inserted by the software way back
                // in antiquity in case none was provided, here for backwards
                // compatability, acc. to brion -ævar
                if( $comment == '' || $comment == '*' ) {
                        return '';
                } else {
                        $formatted = $this->formatComment( $comment, $title, $local );
                        return " <span class=\"comment\">($formatted)</span>";
                }
        }

        /**
         * Wrap and format the given revision's comment block, if the current
         * user is allowed to view it.
         *
         * @param Revision $rev
         * @param bool $local Whether section links should refer to local page
         * @param $isPublic, show only if all users can see it
         * @return string HTML
         */
        function revComment( Revision $rev, $local = false, $isPublic = false ) {
                if( $rev->getRawComment() == "" ) return "";
                if( $rev->isDeleted( Revision::DELETED_COMMENT ) && $isPublic ) {
                        $block = " <span class=\"comment\">" . wfMsgHtml( 'rev-deleted-comment' ) . "</span>";
                } else if( $rev->userCan( Revision::DELETED_COMMENT ) ) {
                        $block = $this->commentBlock( $rev->getComment( Revision::FOR_THIS_USER ),
                                $rev->getTitle(), $local );
                } else {
                        $block = " <span class=\"comment\">" . wfMsgHtml( 'rev-deleted-comment' ) . "</span>";
                }
                if( $rev->isDeleted( Revision::DELETED_COMMENT ) ) {
                        return " <span class=\"history-deleted\">$block</span>";
                }
                return $block;
        }

        public function formatRevisionSize( $size ) {
                if ( $size == 0 ) {
                        $stxt = wfMsgExt( 'historyempty', 'parsemag' );
                } else {
                        global $wgLang;
                        $stxt = wfMsgExt( 'nbytes', 'parsemag', $wgLang->formatNum( $size ) );
                        $stxt = "($stxt)";
                }
                $stxt = htmlspecialchars( $stxt );
                return "<span class=\"history-size\">$stxt</span>";
        }

        /** @todo document */
        function tocIndent() {
                return "\n<ul>";
        }

        /** @todo document */
        function tocUnindent($level) {
                return "</li>\n" . str_repeat( "</ul>\n</li>\n", $level>0 ? $level : 0 );
        }

        /**
         * parameter level defines if we are on an indentation level
         */
        function tocLine( $anchor, $tocline, $tocnumber, $level, $sectionIndex = false ) {
                $classes = "toclevel-$level";
                if ( $sectionIndex !== false )
                        $classes .= " tocsection-$sectionIndex";
                return "\n<li class=\"$classes\"><a href=\"#" .
                        $anchor . '"><span class="tocnumber">' .
                        $tocnumber . '</span> <span class="toctext">' .
                        $tocline . '</span></a>';
        }

        /** @todo document */
        function tocLineEnd() {
                return "</li>\n";
        }

        /** @todo document */
        function tocList($toc) {
                global $wgJsMimeType;
                $title = wfMsgHtml('toc') ;
                return
                   '<table id="toc" class="toc" summary="' . $title .'"><tr><td>'
                 . '<div id="toctitle"><h2>' . $title . "</h2></div>\n"
                 . $toc
                 # no trailing newline, script should not be wrapped in a
                 # paragraph
                 . "</ul>\n</td></tr></table>"
                 . '<script type="' . $wgJsMimeType . '">'
                 . ' if (window.showTocToggle) {'
                 . ' var tocShowText = "' . Xml::escapeJsString( wfMsg('showtoc') ) . '";'
                 . ' var tocHideText = "' . Xml::escapeJsString( wfMsg('hidetoc') ) . '";'
                 . ' showTocToggle();'
                 . ' } '
                 . "</script>\n";
        }
        
        /**
         * Generate a table of contents from a section tree
         * @param $tree Return value of ParserOutput::getSections()
         * @return string HTML
         */
        public function generateTOC( $tree ) {
                $toc = '';
                $lastLevel = 0;
                foreach ( $tree as $section ) {
                        if ( $section['toclevel'] > $lastLevel )
                                $toc .= $this->tocIndent();
                        else if ( $section['toclevel'] < $lastLevel )
                                $toc .= $this->tocUnindent(
                                        $lastLevel - $section['toclevel'] );
                        else
                                $toc .= $this->tocLineEnd();
                        
                        $toc .= $this->tocLine( $section['anchor'],
                                $section['line'], $section['number'],
                                $section['toclevel'], $section['index'] );
                        $lastLevel = $section['toclevel'];
                }
                $toc .= $this->tocLineEnd();
                return $this->tocList( $toc );
        }

        /**
         * Create a section edit link.  This supersedes editSectionLink() and
         * editSectionLinkForOther().
         *
         * @param $nt      Title  The title being linked to (may not be the same as
         *   $wgTitle, if the section is included from a template)
         * @param $section string The designation of the section being pointed to,
         *   to be included in the link, like "&section=$section"
         * @param $tooltip string The tooltip to use for the link: will be escaped
         *   and wrapped in the 'editsectionhint' message
         * @return         string HTML to use for edit link
         */
        public function doEditSectionLink( Title $nt, $section, $tooltip = null ) {
                $attribs = array();
                if( !is_null( $tooltip ) ) {
                        $attribs['title'] = wfMsg( 'editsectionhint', $tooltip );
                }
                $link = $this->link( $nt, wfMsg('editsection'),
                        $attribs,
                        array( 'action' => 'edit', 'section' => $section ),
                        array( 'noclasses', 'known' )
                );

                # Run the old hook.  This takes up half of the function . . . hopefully
                # we can rid of it someday.
                $attribs = '';
                if( $tooltip ) {
                        $attribs = wfMsgHtml( 'editsectionhint', htmlspecialchars( $tooltip ) );
                        $attribs = " title=\"$attribs\"";
                }
                $result = null;
                wfRunHooks( 'EditSectionLink', array( &$this, $nt, $section, $attribs, $link, &$result ) );
                if( !is_null( $result ) ) {
                        # For reverse compatibility, add the brackets *after* the hook is
                        # run, and even add them to hook-provided text.  (This is the main
                        # reason that the EditSectionLink hook is deprecated in favor of
                        # DoEditSectionLink: it can't change the brackets or the span.)
                        $result = wfMsgHtml( 'editsection-brackets', $result );
                        return "<span class=\"editsection\">$result</span>";
                }

                # Add the brackets and the span, and *then* run the nice new hook, with
                # clean and non-redundant arguments.
                $result = wfMsgHtml( 'editsection-brackets', $link );
                $result = "<span class=\"editsection\">$result</span>";

                wfRunHooks( 'DoEditSectionLink', array( $this, $nt, $section, $tooltip, &$result ) );
                return $result;
        }

        /**
         * Create a headline for content
         *
         * @param int    $level   The level of the headline (1-6)
         * @param string $attribs Any attributes for the headline, starting with a space and ending with '>'
         *                        This *must* be at least '>' for no attribs
         * @param string $anchor  The anchor to give the headline (the bit after the #)
         * @param string $text    The text of the header
         * @param string $link    HTML to add for the section edit link
         * @param mixed  $legacyAnchor A second, optional anchor to give for
         *   backward compatibility (false to omit)
         *
         * @return string HTML headline
         */
        public function makeHeadline( $level, $attribs, $anchor, $text, $link, $legacyAnchor = false ) {
                $ret = "<h$level$attribs"
                        . $link
                        . " <span class=\"mw-headline\" id=\"$anchor\">$text</span>"
                        . "</h$level>";
                if ( $legacyAnchor !== false ) {
                        $ret = "<a id=\"$legacyAnchor\"></a>$ret";
                }
                return $ret;
        }

        /**
         * Split a link trail, return the "inside" portion and the remainder of the trail
         * as a two-element array
         *
         * @static
         */
        static function splitTrail( $trail ) {
                static $regex = false;
                if ( $regex === false ) {
                        global $wgContLang;
                        $regex = $wgContLang->linkTrail();
                }
                $inside = '';
                if ( '' != $trail ) {
                        $m = array();
                        if ( preg_match( $regex, $trail, $m ) ) {
                                $inside = $m[1];
                                $trail = $m[2];
                        }
                }
                return array( $inside, $trail );
        }

        /**
         * Generate a rollback link for a given revision.  Currently it's the
         * caller's responsibility to ensure that the revision is the top one. If
         * it's not, of course, the user will get an error message.
         *
         * If the calling page is called with the parameter &bot=1, all rollback
         * links also get that parameter. It causes the edit itself and the rollback
         * to be marked as "bot" edits. Bot edits are hidden by default from recent
         * changes, so this allows sysops to combat a busy vandal without bothering
         * other users.
         *
         * @param Revision $rev
         */
        function generateRollback( $rev ) {
                return '<span class="mw-rollback-link">['
                        . $this->buildRollbackLink( $rev )
                        . ']</span>';
        }

        /**
         * Build a raw rollback link, useful for collections of "tool" links
         *
         * @param Revision $rev
         * @return string
         */
        public function buildRollbackLink( $rev ) {
                global $wgRequest, $wgUser;
                $title = $rev->getTitle();
                $query = array(
                        'action' => 'rollback',
                        'from' => $rev->getUserText()
                );
                if( $wgRequest->getBool( 'bot' ) ) {
                        $query['bot'] = '1';
                        $query['hidediff'] = '1'; // bug 15999
                }
                $query['token'] = $wgUser->editToken( array( $title->getPrefixedText(),
                        $rev->getUserText() ) );
                return $this->link( $title, wfMsgHtml( 'rollbacklink' ),
                        array( 'title' => wfMsg( 'tooltip-rollback' ) ),
                        $query, array( 'known', 'noclasses' ) );
        }

        /**
         * Returns HTML for the "templates used on this page" list.
         *
         * @param array $templates Array of templates from Article::getUsedTemplate
         * or similar
         * @param bool $preview Whether this is for a preview
         * @param bool $section Whether this is for a section edit
         * @return string HTML output
         */
        public function formatTemplates( $templates, $preview = false, $section = false ) {
                wfProfileIn( __METHOD__ );

                $outText = '';
                if ( count( $templates ) > 0 ) {
                        # Do a batch existence check
                        $batch = new LinkBatch;
                        foreach( $templates as $title ) {
                                $batch->addObj( $title );
                        }
                        $batch->execute();

                        # Construct the HTML
                        $outText = '<div class="mw-templatesUsedExplanation">';
                        if ( $preview ) {
                                $outText .= wfMsgExt( 'templatesusedpreview', array( 'parse' ) );
                        } elseif ( $section ) {
                                $outText .= wfMsgExt( 'templatesusedsection', array( 'parse' ) );
                        } else {
                                $outText .= wfMsgExt( 'templatesused', array( 'parse' ) );
                        }
                        $outText .= "</div><ul>\n";

                        usort( $templates, array( 'Title', 'compare' ) );
                        foreach ( $templates as $titleObj ) {
                                $r = $titleObj->getRestrictions( 'edit' );
                                if ( in_array( 'sysop', $r ) ) {
                                        $protected = wfMsgExt( 'template-protected', array( 'parseinline' ) );
                                } elseif ( in_array( 'autoconfirmed', $r ) ) {
                                        $protected = wfMsgExt( 'template-semiprotected', array( 'parseinline' ) );
                                } else {
                                        $protected = '';
                                }
                                if( $titleObj->quickUserCan( 'edit' ) ) {
                                        $editLink = $this->link(
                                                $titleObj,
                                                wfMsg( 'editlink' ),
                                                array(),
                                                array( 'action' => 'edit' )
                                        );
                                } else {
                                        $editLink = $this->link(
                                                $titleObj,
                                                wfMsg( 'viewsourcelink' ),
                                                array(),
                                                array( 'action' => 'edit' )
                                        );
                                }
                                $outText .= '<li>' . $this->link( $titleObj ) . ' (' . $editLink . ') ' . $protected . '</li>';
                        }
                        $outText .= '</ul>';
                }
                wfProfileOut( __METHOD__  );
                return $outText;
        }

        /**
         * Returns HTML for the "hidden categories on this page" list.
         *
         * @param array $hiddencats Array of hidden categories from Article::getHiddenCategories
         * or similar
         * @return string HTML output
         */
        public function formatHiddenCategories( $hiddencats ) {
                global $wgLang;
                wfProfileIn( __METHOD__ );

                $outText = '';
                if ( count( $hiddencats ) > 0 ) {
                        # Construct the HTML
                        $outText = '<div class="mw-hiddenCategoriesExplanation">';
                        $outText .= wfMsgExt( 'hiddencategories', array( 'parse' ), $wgLang->formatnum( count( $hiddencats ) ) );
                        $outText .= "</div><ul>\n";

                        foreach ( $hiddencats as $titleObj ) {
                                $outText .= '<li>' . $this->link( $titleObj, null, array(), array(), 'known' ) . "</li>\n"; # If it's hidden, it must exist - no need to check with a LinkBatch
                        }
                        $outText .= '</ul>';
                }
                wfProfileOut( __METHOD__  );
                return $outText;
        }

        /**
         * Format a size in bytes for output, using an appropriate
         * unit (B, KB, MB or GB) according to the magnitude in question
         *
         * @param $size Size to format
         * @return string
         */
        public function formatSize( $size ) {
                global $wgLang;
                return htmlspecialchars( $wgLang->formatSize( $size ) );
        }

        /**
         * Given the id of an interface element, constructs the appropriate title
         * attribute from the system messages.  (Note, this is usually the id but
         * isn't always, because sometimes the accesskey needs to go on a different
         * element than the id, for reverse-compatibility, etc.)
         *
         * @param string $name    Id of the element, minus prefixes.
         * @param mixed  $options null or the string 'withaccess' to add an access-
         *   key hint
         * @return string Contents of the title attribute (which you must HTML-
         *   escape), or false for no title attribute
         */
        public function titleAttrib( $name, $options = null ) {
                wfProfileIn( __METHOD__ );

                $tooltip = wfMsg( "tooltip-$name" );
                # Compatibility: formerly some tooltips had [alt-.] hardcoded
                $tooltip = preg_replace( "/ ?\[alt-.\]$/", '', $tooltip );

                # Message equal to '-' means suppress it.
                if ( wfEmptyMsg( "tooltip-$name", $tooltip ) || $tooltip == '-' ) {
                        $tooltip = false;
                }

                if ( $options == 'withaccess' ) {
                        $accesskey = $this->accesskey( $name );
                        if( $accesskey !== false ) {
                                if ( $tooltip === false || $tooltip === '' ) {
                                        $tooltip = "[$accesskey]";
                                } else {
                                        $tooltip .= " [$accesskey]";
                                }
                        }
                }

                wfProfileOut( __METHOD__ );
                return $tooltip;
        }

        /**
         * Given the id of an interface element, constructs the appropriate
         * accesskey attribute from the system messages.  (Note, this is usually
         * the id but isn't always, because sometimes the accesskey needs to go on
         * a different element than the id, for reverse-compatibility, etc.)
         *
         * @param string $name    Id of the element, minus prefixes.
         * @return string Contents of the accesskey attribute (which you must HTML-
         *   escape), or false for no accesskey attribute
         */
        public function accesskey( $name ) {
                wfProfileIn( __METHOD__ );

                $accesskey = wfMsg( "accesskey-$name" );

                # FIXME: Per standard MW behavior, a value of '-' means to suppress the
                # attribute, but this is broken for accesskey: that might be a useful
                # value.
                if( $accesskey != '' && $accesskey != '-' && !wfEmptyMsg( "accesskey-$name", $accesskey ) ) {
                        wfProfileOut( __METHOD__ );
                        return $accesskey;
                }

                wfProfileOut( __METHOD__ );
                return false;
        }
        
        /**
         * Creates a (show/hide) link for deleting revisions/log entries
         *
         * @param array $query  Query parameters to be passed to link()
         * @param bool $restricted  Set to true to use a <strong> instead of a <span>
         *
         * @return string HTML <a> link to Special:Revisiondelete, wrapped in a
         * span to allow for customization of appearance with CSS
         */
        public function revDeleteLink( $query = array(), $restricted = false ) {
                $sp = SpecialPage::getTitleFor( 'Revisiondelete' );
                $text = wfMsgHtml( 'rev-delundel' );
                $tag = $restricted ? 'strong' : 'span';
                $link = $this->link( $sp, $text, array(), $query, array( 'known', 'noclasses' ) );
                return Xml::tags( $tag, array( 'class' => 'mw-revdelundel-link' ), "($link)" );
        }

        /* Deprecated methods */

        /**
         * @deprecated
         */
        function postParseLinkColour( $s = null ) {
                wfDeprecated( __METHOD__ );
                return null;
        }


        /**
         * @deprecated Use link()
         *
         * This function is a shortcut to makeLinkObj(Title::newFromText($title),...). Do not call
         * it if you already have a title object handy. See makeLinkObj for further documentation.
         *
         * @param $title String: the text of the title
         * @param $text  String: link text
         * @param $query String: optional query part
         * @param $trail String: optional trail. Alphabetic characters at the start of this string will
         *                      be included in the link text. Other characters will be appended after
         *                      the end of the link.
         */
        function makeLink( $title, $text = '', $query = '', $trail = '' ) {
                wfProfileIn( __METHOD__ );
                $nt = Title::newFromText( $title );
                if ( $nt instanceof Title ) {
                        $result = $this->makeLinkObj( $nt, $text, $query, $trail );
                } else {
                        wfDebug( 'Invalid title passed to Linker::makeLink(): "'.$title."\"\n" );
                        $result = $text == "" ? $title : $text;
                }

                wfProfileOut( __METHOD__ );
                return $result;
        }

        /**
         * @deprecated Use link()
         *
         * This function is a shortcut to makeKnownLinkObj(Title::newFromText($title),...). Do not call
         * it if you already have a title object handy. See makeKnownLinkObj for further documentation.
         *
         * @param $title String: the text of the title
         * @param $text  String: link text
         * @param $query String: optional query part
         * @param $trail String: optional trail. Alphabetic characters at the start of this string will
         *                      be included in the link text. Other characters will be appended after
         *                      the end of the link.
         */
        function makeKnownLink( $title, $text = '', $query = '', $trail = '', $prefix = '',$aprops = '') {
                $nt = Title::newFromText( $title );
                if ( $nt instanceof Title ) {
                        return $this->makeKnownLinkObj( $nt, $text, $query, $trail, $prefix , $aprops );
                } else {
                        wfDebug( 'Invalid title passed to Linker::makeKnownLink(): "'.$title."\"\n" );
                        return $text == '' ? $title : $text;
                }
        }

        /**
         * @deprecated Use link()
         *
         * This function is a shortcut to makeBrokenLinkObj(Title::newFromText($title),...). Do not call
         * it if you already have a title object handy. See makeBrokenLinkObj for further documentation.
         *
         * @param string $title The text of the title
         * @param string $text Link text
         * @param string $query Optional query part
         * @param string $trail Optional trail. Alphabetic characters at the start of this string will
         *                      be included in the link text. Other characters will be appended after
         *                      the end of the link.
         */
        function makeBrokenLink( $title, $text = '', $query = '', $trail = '' ) {
                $nt = Title::newFromText( $title );
                if ( $nt instanceof Title ) {
                        return $this->makeBrokenLinkObj( $nt, $text, $query, $trail );
                } else {
                        wfDebug( 'Invalid title passed to Linker::makeBrokenLink(): "'.$title."\"\n" );
                        return $text == '' ? $title : $text;
                }
        }

        /**
         * @deprecated Use link()
         *
         * This function is a shortcut to makeStubLinkObj(Title::newFromText($title),...). Do not call
         * it if you already have a title object handy. See makeStubLinkObj for further documentation.
         *
         * @param $title String: the text of the title
         * @param $text  String: link text
         * @param $query String: optional query part
         * @param $trail String: optional trail. Alphabetic characters at the start of this string will
         *                      be included in the link text. Other characters will be appended after
         *                      the end of the link.
         */
        function makeStubLink( $title, $text = '', $query = '', $trail = '' ) {
                wfDeprecated( __METHOD__ );
                $nt = Title::newFromText( $title );
                if ( $nt instanceof Title ) {
                        return $this->makeStubLinkObj( $nt, $text, $query, $trail );
                } else {
                        wfDebug( 'Invalid title passed to Linker::makeStubLink(): "'.$title."\"\n" );
                        return $text == '' ? $title : $text;
                }
        }

        /**
         * @deprecated Use link()
         *
         * Make a link for a title which may or may not be in the database. If you need to
         * call this lots of times, pre-fill the link cache with a LinkBatch, otherwise each
         * call to this will result in a DB query.
         *
         * @param $nt     Title: the title object to make the link from, e.g. from
         *                      Title::newFromText.
         * @param $text  String: link text
         * @param $query String: optional query part
         * @param $trail String: optional trail. Alphabetic characters at the start of this string will
         *                      be included in the link text. Other characters will be appended after
         *                      the end of the link.
         * @param $prefix String: optional prefix. As trail, only before instead of after.
         */
        function makeLinkObj( $nt, $text= '', $query = '', $trail = '', $prefix = '' ) {
                wfProfileIn( __METHOD__ );

                $query = wfCgiToArray( $query );
                list( $inside, $trail ) = Linker::splitTrail( $trail );
                if( $text === '' ) {
                        $text = $this->linkText( $nt );
                }

                $ret = $this->link( $nt, "$prefix$text$inside", array(), $query ) . $trail;

                wfProfileOut( __METHOD__ );
                return $ret;
        }

        /**
         * @deprecated Use link()
         *
         * Make a link for a title which definitely exists. This is faster than makeLinkObj because
         * it doesn't have to do a database query. It's also valid for interwiki titles and special
         * pages.
         *
         * @param $nt Title object of target page
         * @param $text   String: text to replace the title
         * @param $query  String: link target
         * @param $trail  String: text after link
         * @param $prefix String: text before link text
         * @param $aprops String: extra attributes to the a-element
         * @param $style  String: style to apply - if empty, use getInternalLinkAttributesObj instead
         * @return the a-element
         */
        function makeKnownLinkObj( $title, $text = '', $query = '', $trail = '', $prefix = '' , $aprops = '', $style = '' ) {
                wfProfileIn( __METHOD__ );

                if ( $text == '' ) {
                        $text = $this->linkText( $title );
                }
                $attribs = Sanitizer::mergeAttributes(
                        Sanitizer::decodeTagAttributes( $aprops ),
                        Sanitizer::decodeTagAttributes( $style )
                );
                $query = wfCgiToArray( $query );
                list( $inside, $trail ) = Linker::splitTrail( $trail );

                $ret = $this->link( $title, "$prefix$text$inside", $attribs, $query,
                        array( 'known', 'noclasses' ) ) . $trail;

                wfProfileOut( __METHOD__ );
                return $ret;
        }

        /**
         * @deprecated Use link()
         *
         * Make a red link to the edit page of a given title.
         *
         * @param $nt Title object of the target page
         * @param $text  String: Link text
         * @param $query String: Optional query part
         * @param $trail String: Optional trail. Alphabetic characters at the start of this string will
         *                      be included in the link text. Other characters will be appended after
         *                      the end of the link.
         */
        function makeBrokenLinkObj( $title, $text = '', $query = '', $trail = '', $prefix = '' ) {
                wfProfileIn( __METHOD__ );

                list( $inside, $trail ) = Linker::splitTrail( $trail );
                if( $text === '' ) {
                        $text = $this->linkText( $title );
                }
                $nt = $this->normaliseSpecialPage( $title );

                $ret = $this->link( $title, "$prefix$text$inside", array(),
                        wfCgiToArray( $query ), 'broken' ) . $trail;

                wfProfileOut( __METHOD__ );
                return $ret;
        }

        /**
         * @deprecated Use link()
         *
         * Make a brown link to a short article.
         *
         * @param $nt Title object of the target page
         * @param $text  String: link text
         * @param $query String: optional query part
         * @param $trail String: optional trail. Alphabetic characters at the start of this string will
         *                      be included in the link text. Other characters will be appended after
         *                      the end of the link.
         */
        function makeStubLinkObj( $nt, $text = '', $query = '', $trail = '', $prefix = '' ) {
                wfDeprecated( __METHOD__ );
                return $this->makeColouredLinkObj( $nt, 'stub', $text, $query, $trail, $prefix );
        }

        /**
         * @deprecated Use link()
         *
         * Make a coloured link.
         *
         * @param $nt Title object of the target page
         * @param $colour Integer: colour of the link
         * @param $text   String:  link text
         * @param $query  String:  optional query part
         * @param $trail  String:  optional trail. Alphabetic characters at the start of this string will
         *                      be included in the link text. Other characters will be appended after
         *                      the end of the link.
         */
        function makeColouredLinkObj( $nt, $colour, $text = '', $query = '', $trail = '', $prefix = '' ) {
                if($colour != ''){
                        $style = $this->getInternalLinkAttributesObj( $nt, $text, $colour );
                } else $style = '';
                return $this->makeKnownLinkObj( $nt, $text, $query, $trail, $prefix, '', $style );
        }

        /** Obsolete alias */
        function makeImage( $url, $alt = '' ) {
                wfDeprecated( __METHOD__ );
                return $this->makeExternalImage( $url, $alt );
        }

        /**
         * Creates the HTML source for images
         * @deprecated use makeImageLink2
         *
         * @param object $title
         * @param string $label label text
         * @param string $alt alt text
         * @param string $align horizontal alignment: none, left, center, right)
         * @param array $handlerParams Parameters to be passed to the media handler
         * @param boolean $framed shows image in original size in a frame
         * @param boolean $thumb shows image as thumbnail in a frame
         * @param string $manualthumb image name for the manual thumbnail
         * @param string $valign vertical alignment: baseline, sub, super, top, text-top, middle, bottom, text-bottom
         * @param string $time, timestamp of the file, set as false for current
         * @return string
         */
        function makeImageLinkObj( $title, $label, $alt, $align = '', $handlerParams = array(), $framed = false,
          $thumb = false, $manualthumb = '', $valign = '', $time = false )
        {
                $frameParams = array( 'alt' => $alt, 'caption' => $label );
                if ( $align ) {
                        $frameParams['align'] = $align;
                }
                if ( $framed ) {
                        $frameParams['framed'] = true;
                }
                if ( $thumb ) {
                        $frameParams['thumbnail'] = true;
                }
                if ( $manualthumb ) {
                        $frameParams['manualthumb'] = $manualthumb;
                }
                if ( $valign ) {
                        $frameParams['valign'] = $valign;
                }
                $file = wfFindFile( $title, $time );
                return $this->makeImageLink2( $title, $file, $frameParams, $handlerParams, $time );
        }

        /** @deprecated use Linker::makeMediaLinkObj() */
        function makeMediaLink( $name, $unused = '', $text = '', $time = false ) {
                $nt = Title::makeTitleSafe( NS_FILE, $name );
                return $this->makeMediaLinkObj( $nt, $text, $time );
        }

        /**
         * Used to generate section edit links that point to "other" pages
         * (sections that are really part of included pages).
         *
         * @deprecated use Linker::doEditSectionLink()
         * @param $title Title string.
         * @param $section Integer: section number.
         */
        public function editSectionLinkForOther( $title, $section ) {
                wfDeprecated( __METHOD__ );
                $title = Title::newFromText( $title );
                return $this->doEditSectionLink( $title, $section );
        }

        /**
         * @deprecated use Linker::doEditSectionLink()
         * @param $nt Title object.
         * @param $section Integer: section number.
         * @param $hint Link String: title, or default if omitted or empty
         */
        public function editSectionLink( Title $nt, $section, $hint = '' ) {
                wfDeprecated( __METHOD__ );
                if( $hint === '' ) {
                        # No way to pass an actual empty $hint here!  The new interface al-
                        # lows this, so we have to do this for compatibility.
                        $hint = null;
                }
                return $this->doEditSectionLink( $nt, $section, $hint );
        }

        /**
         * @deprecated Returns raw bits of HTML, use titleAttrib() and accesskey()
         */
        public function tooltipAndAccesskey( $name ) {
                # FIXME: If Sanitizer::expandAttributes() treated "false" as "output
                # no attribute" instead of "output '' as value for attribute", this
                # would be three lines.
                $attribs = array(
                        'title' => $this->titleAttrib( $name, 'withaccess' ),
                        'accesskey' => $this->accesskey( $name )
                );
                if ( $attribs['title'] === false ) {
                        unset( $attribs['title'] );
                }
                if ( $attribs['accesskey'] === false ) {
                        unset( $attribs['accesskey'] );
                }
                return Xml::expandAttributes( $attribs );
        }

        /** @deprecated Returns raw bits of HTML, use titleAttrib() */
        public function tooltip( $name, $options = null ) {
                # FIXME: If Sanitizer::expandAttributes() treated "false" as "output
                # no attribute" instead of "output '' as value for attribute", this
                # would be two lines.
                $tooltip = $this->titleAttrib( $name, $options );
                if ( $tooltip === false ) {
                        return '';
                }
                return Xml::expandAttributes( array(
                        'title' => $this->titleAttrib( $name, $options )
                ) );
        }
}