add /user/<uid> and /post/<pid> redirects

change notifications to use new redirects

src/posts/topics.js

@@ -1,8 +1,10 @@
 
 'use strict';
 
-var async = require('async'),
-	topics = require('../topics');
+var async = require('async');
+
+var topics = require('../topics');
+var utils = require('../../public/src/utils');
 
 module.exports = function(Posts) {
 
@@ -42,4 +44,49 @@ module.exports = function(Posts) {
 		], callback);
 	};
 
+	Posts.generatePostPath = function (pid, uid, callback) {
+		Posts.generatePostPaths([pid], uid, function(err, paths) {
+			callback(err, Array.isArray(paths) && paths.length ? paths[0] : null);
+		});
+	};
+
+	Posts.generatePostPaths = function (pids, uid, callback) {
+		async.waterfall([
+			function (next) {
+				Posts.getPostsFields(pids, ['pid', 'tid'], next);
+			},
+			function (postData, next) {
+				async.parallel({
+					indices: function(next) {
+						Posts.getPostIndices(postData, uid, next);
+					},
+					topics: function(next) {
+						var tids = postData.map(function(post) {
+							return post ? post.tid : null;
+						});
+
+						topics.getTopicsFields(tids, ['slug', 'deleted'], next);
+					}
+				}, next);
+			},
+			function (results, next) {
+				var paths = pids.map(function(pid, index) {
+					if (parseInt(results.topics[index].deleted, 10) === 1) {
+						return null;
+					}
+
+					var slug = results.topics[index] ? results.topics[index].slug : null;
+					var postIndex = utils.isNumber(results.indices[index]) ? parseInt(results.indices[index], 10) + 1 : null;
+
+					if (slug && postIndex) {
+						return '/topic/' + slug + '/' + postIndex;
+					}
+					return null;
+				});
+
+				next(null, paths);
+			}
+		], callback);
+	};
+
 };