User:Evad37/TextDiff.js

 /***************************************************************************************************
  TextDiff --- by Evad37
  > Shows a simpler, text-only diff
  > Alpha version
 ***************************************************************************************************/
 // <nowiki>
 $(function($){

 /* ========== Load dependencies ================================================================= */
 // Load resoucre loader modules
 mw.loader.using(['mediawiki.util','mediawiki.api','ext.gadget.libExtraUtil'],function(){

 // Do not operate if not viewing a diff, or if there is no difference
 if(!mw.util.getParamValue('diff')||$('.mw-diff-empty').length){
 return;
 }

 varconfig={
 'script':{
 'version':'0.3.0-alpha'
 },
 'params':{
 'diff':mw.util.getParamValue('diff'),
 'oldid':mw.util.getParamValue('oldid')
 },
 'mw':mw.config.get(['wgPageName','wgCurRevisionId'])
 };

 varapi=newmw.Api({
 ajax:{
 headers:{
 'Api-User-Agent':'TextDiff/'+config.script.version+
 ' ( https://en.wikipedia.org/wiki/User:Evad37/TextDiff )'
 }
 }
 });

 /* ========= Processing functions =============================================================== */

 /**
  * normaliseIds
  *
  * Get normalised revision ids (lookup the current / previous / next id if present)
  * @param
  */
 varnormaliseIds=function(diffParam,oldidParam,title){
 varrelativeDiffWords=['cur','prev','next'];

 if(!diffParam){
 return$.Deferred().reject('No diff specified');
 }
 if(!$.isNumeric(diffParam)&&relativeDiffWords.indexOf(diffParam)===-1){
 return$.Deferred().reject("Bad diff specified: Must be numeric or one of 'cur', 'prev', 'next'");
 }

 // Both params have numeric ids
 if($.isNumeric(diffParam)&&$.isNumeric(oldidParam)){
 return$.Deferred().resolve({
 'from':oldidParam,
 'to':diffParam
 });
 }

 // Neither param has a numeric ids 
 if(!$.isNumeric(diffParam)&&!$.isNumeric(oldidParam)){
 returnlookupIdsFromRelation(
 'prev',
 config.mw.wgCurRevisionId,
 title
 );
 }

 // Only diff param has a numeric id
 if($.isNumeric(diffParam)){
 returnlookupIdsFromRelation(oldidParam,diffParam,title);
 }

 // Only oldid param has a numeric id
 returnlookupIdsFromRelation(diffParam,oldidParam,title);
 };

 /**
  * lookupIdsFromRelation
  *
  * @param
  */
 varlookupIdsFromRelation=function(relation,otherId,title){
 returnapi.get({
 action:'compare',
 format:'json',
 fromrev:otherId,//|| false,
 fromtitle:($.isNumeric(otherId))?'':title,
 torelative:relation,
 prop:'ids'
 })
 .then(function(result){
 return{
 'from':result.compare.fromrevid,
 'to':result.compare.torevid||config.mw.wgCurRevisionId
 };
 });
 };

 /**
  * makeText
  *
  * Shorthand for #grabWikitext then #toPlaintext
  */
 varmakeText=function(id){returngrabWikitext(id).then(toPlaintext);};

 /**
  * grabWikitext
  *
  * Gets the wikitext and page title of a specific revision of a page
  *
  * @param {string} page
  * Page title
  * @param {int} revid
  * Old revision id
  * @return {Deferred} Promise that is resolved with: {object} results, with keys
  * wikitext: {string},
  * pageTitle: {string}
  */
 vargrabWikitext=function(revid){

 returnapi.get({
 "action":"query",
 "format":"json",
 "prop":"revisions",
 "revids":revid,
 "rvprop":"content"
 })
 .then(function(response){
 varpageid=Object.keys(response.query.pages)[0];
 varwikitext=response.query.pages[pageid].revisions[0]['*'];
 vartitle=response.query.pages[pageid].title;
 return{'wikitext':wikitext,'pageTitle':title};
 });

 };

 /**
  * toPlaintext
  *
  * Transforms a wikitext string into a plaintext string. Images are replaced with alt text.
  *
  * @param {object} info
  *	 @param {string} info.wikitext
  * Wikitext to be expanded
  * @param {string} info.pageTitle
  * Page title, to give context to variables like {{PAGENAME}} 
  * @return {Deferred} Promise that is resolved with: {string} transformed wikitext
  */
 vartoPlaintext=function(info){
 returnapi.post({
 "action":"parse",
 "format":"json",
 "title":info.pageTitle,
 "text":info.wikitext,
 "prop":"text",
 "disablelimitreport":1,
 "disableeditsection":1,
 "contentmodel":"wikitext",
 "mobileformat":1,
 "noimages":1
 })
 .then(function(response){returnresponse.parse.text['*'];})
 .then(function(parsetext){return$(parsetext).text();});
 };

 /*
 Strip lines where that line, the two previous lines, and the two next lines, are identical.
 Parameters are arrays of text, with one line of text per array element
 */
 varstripIdenticalLines=function(lines,otherLines){
 returnlines.map(function(line,index){
 if(
 lines[index-2]===otherLines[index-2]&&
 lines[index-1]===otherLines[index-1]&&
 lines[index]===otherLines[index]&&
 lines[index+1]===otherLines[index+1]&&
 lines[index+2]===otherLines[index+2]
 ){
 return'';
 }
 returnline;
 });
 };

 varstripIdenticalText=function(fromText,toText){
 varfromLines=fromText.split('\n');
 vartoLines=toText.split('\n');
 return$.Deferred().resolve(
 stripIdenticalLines(fromLines,toLines).join('\n'),
 stripIdenticalLines(toLines,fromLines).join('\n')
 );
 };

 /**
  * makeDiff
  *
  * @param
  */
 varmakeDiff=function(fromText,toText){
 returnapi.post({
 "action":"compare",
 "format":"json",
 "fromtext":fromText,
 "fromcontentmodel":"text",
 "totext":toText,
 "tocontentmodel":"text",
 "prop":"diff"
 })
 .then(function(response){returnresponse.compare['*'];});
 };

 /**
  * showDiff
  *
  * @param
  */
 varshowDiff=function(diffRow){
 $(diffRow).filter('tr').addClass('textdiff-row').hide().insertAfter('#textDiff-buttonRow').show('fast');
 $('tr.textdiff-row').last().nextAll().addClass('origdiff-row').hide('fast');
 $('#textDiff-button').prop('disabled',false).text('Toggle textual diff');
 };

 varonError=function(code,jqxhr){
 $('#textDiff-button').text('Error loading textual diff').after(
 $('<div>').addClass('error').append(extraJs.makeErrorMsg(code,jqxhr))
 );
 };


 /* ========= Set up =============================================================== */
 vardoTextDiff=function(diffParam,oldIdParam,pageName){
 normaliseIds(diffParam,oldIdParam,pageName)
 .then(function(ids){
 return$.when(makeText(ids.from),makeText(ids.to));
 })
 .then(stripIdenticalText)
 .then(makeDiff)
 .then(showDiff,onError);
 };

 var$buttonRow=$('<tr>').attr('id','textDiff-buttonRow').append(
 $('<td>').attr('id','textDiff-buttonCell').append(
 $('<div>').css('text-align','center').append(
 $('<button>')
 .attr('title','Show textual diff view')
 .text('Textual diff')
 .click(function(){
 $(this).hide().next().show();
 doTextDiff(config.params.diff,config.params.oldid,config.mw.wgPageName);
 }),

 $('<button>')
 .attr({'id':'textDiff-button','title':'Toggle textual diff view'})
 .text('Textual diff loading...')
 .prop('disabled','true')
 .hide()
 .click(function(){
 $('tr.textdiff-row, tr.origdiff-row').toggle();
 })
 )
 )
 );

 $('table.diff').find('tr').first().after($buttonRow);
 $('#textDiff-buttonCell').attr('colspan','4');

 /* ========== Export code for testing by /test.js =============================================== */
 window.testTextDiff={
 'config':config,
 'api':api,
 'normaliseIds':normaliseIds,
 'lookupIdsFromRelation':lookupIdsFromRelation,
 'makeText':makeText,
 'grabWikitext':grabWikitext,
 'toPlaintext':toPlaintext,
 'makeDiff':makeDiff,
 'showDiff':showDiff,
 'doTextDiff':doTextDiff
 };

 });
 });
 // </nowiki>