User:Yair rand/ShowTalkLabels.js

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$( function () {
  
  function fromTalk( pageName ) {
    var [ ns, title ] = pageName.split( ':' );
    return ns === 'Talk' ? title : 'Property:' + title;
  }
  
  function fetchLabel( titles ) {
  	return fetch( '/w/api.php?format=json&action=query&prop=pageterms&wbptterms=label&titles=' + titles ).then( x => x.json() );
  }
  
  if ( ( [ 'Recentchanges', 'Watchlist', 'Recentchangeslinked', 'Contributions' ] ).includes( mw.config.get( 'wgCanonicalSpecialPageName' ) ) ) {
    let talkLinks = Array.from( document.querySelectorAll( '.mw-title > a, .mw-contributions-title' ) )
        .filter( link => [ 'Talk', 'Property talk' ].includes( link.title.split( ':' )[ 0 ] ) ),
      titles = [ ...new Set( talkLinks.map( link => link.title ) ) ],
      fetchTitles = () => titles.length === 0 ? Promise.resolve( [] ) : fetchLabel( 
          titles.splice( 0, 50 ).map( title => fromTalk( title ) ).join( '|' )
        )
        .then( results => fetchTitles().then( titles => titles.concat( Object.values( results.query.pages ) ) ) );
    titles.length && fetchTitles().then( results => {
      var map = {};
      results.forEach( page => {
        map[ page.title ] = page.terms && page.terms.label[ 0 ];
      } );
      talkLinks.forEach( link => {
        var title = map[ fromTalk( link.title ) ];
        if ( title ) {
          link.innerText += ' (' + title + ')';
        }
      } );
    } );
  }
    
  if ( [ 'Talk', 'Property_talk' ].includes( mw.config.get('wgCanonicalNamespace') ) ) {
    fetchLabel( fromTalk( mw.config.get( 'wgPageName' ) ) )
      .then( result => {
        var title = Object.values( result.query.pages )[ 0 ].terms.label[ 0 ],
          titlestr = ' (' + title + ')';
        document.querySelector( '#firstHeading' ).appendChild( document.createTextNode( titlestr ) );
        document.title = document.title.replace(' – ', titlestr + ' – ');
      } );
  }
} );