IS improvements

* simplify calculation (scrollTop vs elementInView)
* use post anchor rather than create big $ objs from post html
* pressing f5 repeatedly now always takes you to the correct pid

public/src/client/topic.js

@@ -61,7 +61,7 @@ define('forum/topic', [
 
 		handleKeys();
 
-		navigator.init('[component="post"]', ajaxify.data.postcount, Topic.toTop, Topic.toBottom, Topic.navigatorCallback, Topic.calculateIndex);
+		navigator.init('[component="post/anchor"]', ajaxify.data.postcount, Topic.toTop, Topic.toBottom, Topic.navigatorCallback, Topic.calculateIndex);
 
 		$(window).on('scroll', updateTopicTitle);
 
@@ -219,43 +219,30 @@ define('forum/topic', [
 		return index;
 	};
 
-	Topic.navigatorCallback = function(topPostIndex, bottomPostIndex, elementCount) {
+	Topic.navigatorCallback = function(index, elementCount) {
 		var path = ajaxify.removeRelativePath(window.location.pathname.slice(1));
 		if (!path.startsWith('topic')) {
 			return 1;
 		}
-		var postIndex = topPostIndex;
-		var index = bottomPostIndex;
-		if (config.topicPostSort !== 'oldest_to_newest') {
-			if (bottomPostIndex === 0) {
-				index = 1;
-			} else  {
-				index = Math.max(elementCount - bottomPostIndex + 2, 1);
-			}
-		}
 
 		var bookmarkKey = 'topic:' + ajaxify.data.tid + ':bookmark';
 		var currentBookmark = ajaxify.data.bookmark || localStorage.getItem(bookmarkKey);
 
-		if (!currentBookmark || parseInt(postIndex, 10) > parseInt(currentBookmark, 10)) {
+		if (!currentBookmark || parseInt(index, 10) > parseInt(currentBookmark, 10)) {
 			if (app.user.uid) {
-				var payload = {
+				socket.emit('topics.bookmark', {
 					'tid': ajaxify.data.tid,
-					'index': postIndex
-				};
-				socket.emit('topics.bookmark', payload, function(err) {
-					if (err) {
-						console.warn('Error saving bookmark:', err);
-					}
-					ajaxify.data.bookmark = postIndex;
+					'index': index
+				}, function(err) {
+					ajaxify.data.bookmark = index;
 				});
 			} else {
-				localStorage.setItem(bookmarkKey, postIndex);
+				localStorage.setItem(bookmarkKey, index);
 			}
 		}
 
 		// removes the bookmark alert when we get to / past the bookmark
-		if (!currentBookmark || parseInt(postIndex, 10) >= parseInt(currentBookmark, 10)) {
+		if (!currentBookmark || parseInt(index, 10) >= parseInt(currentBookmark, 10)) {
 			app.removeAlert('bookmark');
 		}
 
@@ -264,14 +251,15 @@ define('forum/topic', [
 			var topicId = parts[1],
 				slug = parts[2];
 			var newUrl = 'topic/' + topicId + '/' + (slug ? slug : '');
-			if (postIndex > 1) {
-				newUrl += '/' + postIndex;
+			if (index > 1) {
+				newUrl += '/' + index;
 			}
 
 			if (newUrl !== currentUrl) {
 				if (Topic.replaceURLTimeout) {
 					clearTimeout(Topic.replaceURLTimeout);
 				}
+
 				Topic.replaceURLTimeout = setTimeout(function() {
 					Topic.replaceURLTimeout = 0;
 					if (history.replaceState) {
@@ -284,7 +272,6 @@ define('forum/topic', [
 				}, 500);
 			}
 		}
-		return index;
 	};
 
 

public/src/modules/navigator.js

@@ -90,28 +90,21 @@ define('navigator', ['forum/pagination', 'components'], function(pagination, com
 	navigator.update = function() {
 		toggle(!!count);
 
-		var topIndex = 0;
-		var bottomIndex = 0;
+		var middleOfViewport = $(window).scrollTop() + $(window).height() / 2;
+		
+		index = 0;
+
 		$(navigator.selector).each(function() {
 			var el = $(this);
 
-			if (elementInView(el)) {
-				if (!topIndex) {
-					topIndex = parseInt(el.attr('data-index'), 10) + 1;
-				} else {
-					bottomIndex = parseInt(el.attr('data-index'), 10) + 1;
-				}
-			} else if (topIndex && bottomIndex) {
+			index++;
+			if (el.offset().top > middleOfViewport) {
 				return false;
 			}
 		});
 
-		if (topIndex && !bottomIndex) {
-			bottomIndex = topIndex;
-		}
-
-		if (typeof navigator.callback === 'function' && topIndex && bottomIndex) {
-			index = navigator.callback(topIndex, bottomIndex, count);
+		if (typeof navigator.callback === 'function') {
+			navigator.callback(index, count);
 			navigator.updateTextAndProgressBar();
 		}
 	};
@@ -155,16 +148,6 @@ define('navigator', ['forum/pagination', 'components'], function(pagination, com
 		}
 	};
 
-	function elementInView(el) {
-		var scrollTop = $(window).scrollTop() + $('#header-menu').height();
-		var scrollBottom = scrollTop + $(window).height();
-
-		var elTop = el.offset().top;
-		var elBottom = elTop + Math.floor(el.height());
-
-		return (elTop >= scrollTop && elBottom < scrollBottom) || (elTop < scrollTop && elBottom > scrollTop);
-	}
-
 	navigator.scrollToPost = function(postIndex, highlight, duration, offset) {
 		if (!utils.isNumber(postIndex) || !components.get('topic').length) {
 			return;