From 091723a8c56e51a63390c08bd15240e6ae13ddb8 Mon Sep 17 00:00:00 2001
From: Baris Soner Usakli <barisusakli@gmail.com>
Date: Thu, 27 Feb 2014 23:45:12 -0500
Subject: [PATCH] closes #1101

---
 public/src/ajaxify.js         |   8 +-
 public/src/app.js             |   7 +-
 public/src/forum/category.js  | 205 ++++++++++++++++++++++++++++++----
 public/templates/category.tpl |   2 +-
 src/categories.js             |  23 +++-
 src/socket.io/posts.js        |   4 +-
 src/socket.io/topics.js       |  10 +-
 src/topics.js                 |  20 ++++
 8 files changed, 250 insertions(+), 29 deletions(-)

diff --git a/public/src/ajaxify.js b/public/src/ajaxify.js
index 6b88546cba..47a6a0b2a0 100644
--- a/public/src/ajaxify.js
+++ b/public/src/ajaxify.js
@@ -21,8 +21,9 @@ var ajaxify = {};
 
 	window.onpopstate = function (event) {
 		if (event !== null && event.state && event.state.url !== undefined && !ajaxify.initialLoad) {
-			ajaxify.go(event.state.url, null, true);
-			$(window).trigger('action:popstate', {url: event.state.url});
+			ajaxify.go(event.state.url, function() {
+				$(window).trigger('action:popstate', {url: event.state.url});
+			}, true);
 		}
 	};
 
@@ -30,6 +31,7 @@ var ajaxify = {};
 	ajaxify.initialLoad = false;
 
 	ajaxify.go = function (url, callback, quiet) {
+
 		// "quiet": If set to true, will not call pushState
 		app.enterRoom('global');
 
@@ -102,7 +104,7 @@ var ajaxify = {};
 					}
 				});
 
-				if (callback) {
+				if (typeof callback === 'function') {
 					callback();
 				}
 
diff --git a/public/src/app.js b/public/src/app.js
index 17415d392d..3201e2b563 100644
--- a/public/src/app.js
+++ b/public/src/app.js
@@ -446,15 +446,18 @@ var socket,
 
 	var previousScrollTop = 0;
 
+
+
 	app.enableInfiniteLoading = function(callback) {
 		$(window).off('scroll').on('scroll', function() {
+
 			var top = $(window).height() * 0.1;
 			var bottom = ($(document).height() - $(window).height()) * 0.9;
 			var currentScrollTop = $(window).scrollTop();
 
-			if($(window).scrollTop() < top && previousScrollTop > currentScrollTop) {
+			if(currentScrollTop < top && currentScrollTop < previousScrollTop) {
 				callback(-1);
-			} else if ($(window).scrollTop() > bottom && previousScrollTop < currentScrollTop) {
+			} else if (currentScrollTop > bottom && currentScrollTop > previousScrollTop) {
 				callback(1);
 			}
 			previousScrollTop = currentScrollTop;
diff --git a/public/src/forum/category.js b/public/src/forum/category.js
index da62a01226..9e778148e6 100644
--- a/public/src/forum/category.js
+++ b/public/src/forum/category.js
@@ -2,10 +2,6 @@ define(['composer', 'forum/pagination'], function(composer, pagination) {
 	var Category = {},
 		loadingMoreTopics = false;
 
-	$(window).on('action:popstate', function(ev, data) {
-
-	});
-
 	Category.init = function() {
 		var	cid = templates.get('category_id'),
 			categoryName = templates.get('category_name'),
@@ -42,13 +38,128 @@ define(['composer', 'forum/pagination'], function(composer, pagination) {
 		socket.on('event:new_topic', Category.onNewTopic);
 
 		enableInfiniteLoading();
+
+		$('#topics-container').on('click', '.topic-title', function() {
+			var clickedTid = $(this).parents('li.category-item[data-tid]').attr('data-tid');
+			$('#topics-container li.category-item').each(function(index, el) {
+				if($(el).offset().top - $(window).scrollTop() > 0) {
+					tid = $(el).attr('data-tid');
+
+					localStorage.setItem('category:bookmark', tid);
+					localStorage.setItem('category:bookmark:clicked', clickedTid);
+					return false;
+				}
+			});
+		});
+	};
+
+	$(window).on('action:popstate', function(ev, data) {
+		if(data.url.indexOf('category/') === 0) {
+			var bookmark = localStorage.getItem('category:bookmark');
+			var clicked = localStorage.getItem('category:bookmark:clicked');
+
+			if (bookmark) {
+
+				if(config.usePagination) {
+					socket.emit('topics.getTidPage', bookmark, function(err, page) {
+						if(err) {
+							return;
+						}
+						if(parseInt(page, 10) !== pagination.currentPage) {
+							pagination.loadPage(page);
+						} else {
+							Category.scrollToTopic(bookmark, clicked, 400);
+						}
+					});
+				} else {
+
+					socket.emit('topics.getTidIndex', bookmark, function(err, index) {
+						if(err) {
+							return;
+						}
+
+						if(index === 0) {
+							Category.highlightTopic(clicked);
+							return;
+						}
+
+						if (index < 0) {
+							index = 0;
+						}
+
+						$('#topics-container').empty();
+						loadingMoreTopics = false;
+
+						Category.loadMoreTopics(templates.get('category_id'), after, function() {
+							Category.scrollToTopic(bookmark, clicked, 0);
+						});
+					});
+				}
+			}
+		}
+	});
+
+	Category.highlightTopic = function(tid) {
+		var highlight = $('#topics-container li.category-item[data-tid="' + tid + '"]');
+		if(highlight.length && !highlight.hasClass('highlight')) {
+			highlight.addClass('highlight');
+			setTimeout(function() {
+				highlight.removeClass('highlight');
+			}, 5000);
+		}
+	};
+
+	Category.scrollToTopic = function(tid, clickedTid, duration, offset) {
+		if(!tid) {
+			return;
+		}
+
+		if(!offset) {
+			offset = 0;
+		}
+
+		if($('#topics-container li.category-item[data-tid="' + tid + '"]').length) {
+			var	cid = templates.get('category_id');
+			var scrollTo = $('#topics-container li.category-item[data-tid="' + tid + '"]');
+
+			if (cid && scrollTo.length) {
+				$('html, body').animate({
+					scrollTop: (scrollTo.offset().top - $('#header-menu').height() - offset) + 'px'
+				}, duration !== undefined ? duration : 400, function() {
+					Category.highlightTopic(clickedTid);
+				});
+			}
+		}
 	};
 
 	function enableInfiniteLoading() {
 		if(!config.usePagination) {
-			app.enableInfiniteLoading(function() {
-				if(!loadingMoreTopics) {
-					Category.loadMoreTopics(templates.get('category_id'));
+			app.enableInfiniteLoading(function(direction) {
+
+				if(!loadingMoreTopics && $('#topics-container').children().length) {
+
+					var after = 0;
+					var el = null;
+
+					if(direction > 0) {
+						el = $('#topics-container .category-item[data-tid]').last();
+						after = parseInt(el.attr('data-index'), 10) + 1;
+					} else {
+						el = $('#topics-container .category-item[data-tid]').first();
+						after = parseInt(el.attr('data-index'), 10);
+						after -= config.topicsPerPage;
+						if(after < 0) {
+							after = 0;
+						}
+					}
+
+					var offset = el.offset().top - $('#header-menu').offset().top + $('#header-menu').height();
+
+					Category.loadMoreTopics(templates.get('category_id'), after, function() {
+						if(direction < 0 && el) {
+							Category.scrollToTopic(el.attr('data-tid'), null, 0, offset);
+						}
+					});
 				}
 			});
 		} else {
@@ -98,56 +209,112 @@ define(['composer', 'forum/pagination'], function(composer, pagination) {
 
 			$(window).trigger('action:categories.new_topic.loaded');
 		});
-	}
+	};
+
+	Category.onTopicsLoaded = function(topics, callback) {
+		if(!topics || !topics.length) {
+			return;
+		}
+
+		function removeAlreadyAddedTopics() {
+			topics = topics.filter(function(topic) {
+				return $('#topics-container li[data-tid="' + topic.tid +'"]').length === 0;
+			});
+		}
+
+		var after = null,
+			before = null;
+
+		function findInsertionPoint() {
+			if (!$('#topics-container .category-item[data-tid]').length) {
+				return;
+			}
+			var last = $('#topics-container .category-item[data-tid]').last();
+			var lastIndex = last.attr('data-index');
+			var firstIndex = topics[topics.length - 1].index;
+			if (firstIndex > lastIndex) {
+				after = last;
+			} else {
+				before = $('#topics-container .category-item[data-tid]').first();
+			}
+		}
+
+		removeAlreadyAddedTopics();
+		if(!topics.length) {
+			return;
+		}
+
+		findInsertionPoint();
 
-	Category.onTopicsLoaded = function(topics) {
 		var html = templates.prepare(templates['category'].blocks['topics']).parse({
 			topics: topics
 		});
 
 		translator.translate(html, function(translatedHTML) {
-			var container = $('#topics-container');
+			var container = $('#topics-container'),
+				html = $(translatedHTML);
 
 			$('#topics-container, .category-sidebar').removeClass('hidden');
 			$('#category-no-topics').remove();
 
-			html = $(translatedHTML);
-
 			if(config.usePagination) {
 				container.empty().append(html);
 			} else {
-				container.append(html);
+				if(after) {
+					html.insertAfter(after);
+				} else if(before) {
+					html.insertBefore(before);
+				} else {
+					container.append(html);
+				}
 			}
 
 			$('#topics-container span.timeago').timeago();
 			app.createUserTooltips();
 			app.makeNumbersHumanReadable(html.find('.human-readable-number'));
+
+			if (typeof callback === 'function') {
+				callback(topics);
+			}
 		});
-	}
+	};
 
-	Category.loadMoreTopics = function(cid) {
+	Category.loadMoreTopics = function(cid, after, callback) {
 		if (loadingMoreTopics || !$('#topics-container').length) {
 			return;
 		}
 
+		if(after === 0 && $('#topics-container li.category-item[data-index="0"]').length) {
+			return;
+		}
+
 		$(window).trigger('action:categories.loading');
 		loadingMoreTopics = true;
+
 		socket.emit('categories.loadMore', {
 			cid: cid,
-			after: $('#topics-container').attr('data-nextstart')
+			after: after
 		}, function (err, data) {
+			loadingMoreTopics = false;
+
 			if(err) {
 				return app.alertError(err.message);
 			}
 
 			if (data && data.topics.length) {
-				Category.onTopicsLoaded(data.topics);
+				Category.onTopicsLoaded(data.topics, callback);
 				$('#topics-container').attr('data-nextstart', data.nextStart);
+			} else {
+
+				if (typeof callback === 'function') {
+					callback(data.topics);
+				}
 			}
-			loadingMoreTopics = false;
+
+
 			$(window).trigger('action:categories.loaded');
 		});
-	}
+	};
 
 	return Category;
 });
\ No newline at end of file
diff --git a/public/templates/category.tpl b/public/templates/category.tpl
index 25bc8c0a31..f1b6a9c365 100644
--- a/public/templates/category.tpl
+++ b/public/templates/category.tpl
@@ -39,7 +39,7 @@
 		<ul id="topics-container" itemscope itemtype="http://www.schema.org/ItemList" data-nextstart="{nextStart}">
 			<meta itemprop="itemListOrder" content="descending">
 			<!-- BEGIN topics -->
-			<li class="category-item <!-- IF topics.deleted -->deleted<!-- ENDIF topics.deleted --><!-- IF topics.unread -->unread<!-- ENDIF topics.unread -->" itemprop="itemListElement">
+			<li class="category-item <!-- IF topics.deleted -->deleted<!-- ENDIF topics.deleted --><!-- IF topics.unread -->unread<!-- ENDIF topics.unread -->" itemprop="itemListElement" data-tid="{topics.tid}" data-index="{topics.index}">
 
 				<div class="col-md-12 col-xs-12 panel panel-default topic-row">
 
diff --git a/src/categories.js b/src/categories.js
index 48af337280..5a86d8532c 100644
--- a/src/categories.js
+++ b/src/categories.js
@@ -85,11 +85,13 @@ var db = require('./database'),
 	};
 
 	Categories.getCategoryTopics = function(cid, start, stop, uid, callback) {
+		var tids;
 		async.waterfall([
 			function(next) {
 				Categories.getTopicIds(cid, start, stop, next);
 			},
-			function(tids, next) {
+			function(topicIds, next) {
+				tids = topicIds;
 				topics.getTopicsByTids(tids, uid, next);
 			},
 			function(topics, next) {
@@ -100,6 +102,15 @@ var db = require('./database'),
 					});
 				}
 
+				var indices = {};
+				for(var i=0; i<tids.length; ++i) {
+					indices[tids[i]] = start + i;
+				}
+
+				for(var i=0; i<topics.length; ++i) {
+					topics[i].index = indices[topics[i].tid];
+				}
+
 				db.sortedSetRevRank('categories:' + cid + ':tid', topics[topics.length - 1].tid, function(err, rank) {
 					if(err) {
 						return next(err);
@@ -118,6 +129,16 @@ var db = require('./database'),
 		db.getSortedSetRevRange('categories:' + cid + ':tid', start, stop, callback);
 	};
 
+	Categories.getTopicIndex = function(tid, callback) {
+		topics.getTopicField(tid, 'cid', function(err, cid) {
+			if(err) {
+				return callback(err);
+			}
+
+			db.sortedSetRevRank('categories:' + cid + ':tid', tid, callback);
+		});
+	};
+
 	Categories.getPageCount = function(cid, uid, callback) {
 		db.sortedSetCard('categories:' + cid + ':tid', function(err, topicCount) {
 			if(err) {
diff --git a/src/socket.io/posts.js b/src/socket.io/posts.js
index dcbf85daa1..df0ebfeebd 100644
--- a/src/socket.io/posts.js
+++ b/src/socket.io/posts.js
@@ -243,11 +243,11 @@ SocketPosts.getFavouritedUsers = function(socket, pid, callback) {
 
 SocketPosts.getPidPage = function(socket, pid, callback) {
 	posts.getPidPage(pid, socket.uid, callback);
-}
+};
 
 SocketPosts.getPidIndex = function(socket, pid, callback) {
 	posts.getPidIndex(pid, callback);
-}
+};
 
 SocketPosts.flag = function(socket, pid, callback) {
 	if (!socket.uid) {
diff --git a/src/socket.io/topics.js b/src/socket.io/topics.js
index e96fc2611d..ec19101cd2 100644
--- a/src/socket.io/topics.js
+++ b/src/socket.io/topics.js
@@ -1,4 +1,5 @@
 var topics = require('../topics'),
+	categories = require('../categories'),
 	threadTools = require('../threadTools'),
 	index = require('./index'),
 	user = require('../user'),
@@ -291,9 +292,16 @@ SocketTopics.loadMoreFromSet = function(socket, data, callback) {
 	topics.getTopicsFromSet(socket.uid, data.set, start, end, callback);
 };
 
-
 SocketTopics.getPageCount = function(socket, tid, callback) {
 	topics.getPageCount(tid, socket.uid, callback);
 };
 
+SocketTopics.getTidPage = function(socket, tid, callback) {
+	topics.getTidPage(tid, socket.uid, callback);
+};
+
+SocketTopics.getTidIndex = function(socket, tid, callback) {
+	categories.getTopicIndex(tid, callback);
+};
+
 module.exports = SocketTopics;
\ No newline at end of file
diff --git a/src/topics.js b/src/topics.js
index 1c2727f5ff..e0c56b52f5 100644
--- a/src/topics.js
+++ b/src/topics.js
@@ -426,6 +426,26 @@ var async = require('async'),
 		});
 	};
 
+	Topics.getTidPage = function(tid, uid, callback) {
+		if(!tid) {
+			return callback(new Error('invalid-tid'));
+		}
+
+		async.parallel({
+			index: function(next) {
+				categories.getTopicIndex(tid, next);
+			},
+			settings: function(next) {
+				user.getSettings(uid, next);
+			}
+		}, function(err, results) {
+			if(err) {
+				return callback(err);
+			}
+			callback(null, Math.ceil((results.index + 1) / results.settings.topicsPerPage));
+		});
+	};
+
 	Topics.getCategoryData = function(tid, callback) {
 		Topics.getTopicField(tid, 'cid', function(err, cid) {
 			if(err) {