Add remaining scanning time (fixes #2484)

gui/syncthing/core/syncthingController.js

@@ -2,7 +2,7 @@ angular.module('syncthing.core')
     .config(function($locationProvider) {
         $locationProvider.html5Mode(true).hashPrefix('!');
     })
-    .controller('SyncthingController', function ($scope, $http, $location, LocaleService, Events) {
+    .controller('SyncthingController', function ($scope, $http, $location, LocaleService, Events, $filter) {
         'use strict';
 
         // private/helper definitions
@@ -676,6 +676,62 @@ angular.module('syncthing.core')
             return $scope.scanProgress[folder].rate;
         }
 
+        $scope.scanRemaining = function (folder) {
+            // Formats the remaining scan time as a string. Includes days and
+            // hours only when relevant, resulting in time stamps like:
+            // 00m 40s
+            // 32m 40s
+            // 2h 32m
+            // 4d 2h
+
+            var res = [];
+
+            if (!$scope.scanProgress[folder]) {
+                return "";
+            }
+
+            // Calculate remaining bytes and seconds based on our current
+            // rate.
+            var remainingBytes = $scope.scanProgress[folder].total - $scope.scanProgress[folder].current;
+            var seconds = remainingBytes / $scope.scanProgress[folder].rate;
+
+            // Round up to closest ten seconds to avoid flapping too much to
+            // and fro.
+            seconds = Math.ceil(seconds / 10) * 10;
+
+            // Separate out the number of days.
+            var days = 0;
+            if (seconds >= 86400) {
+                days = Math.floor(seconds / 86400);
+                res.push('' + days + 'd')
+                seconds = seconds % 86400;
+            }
+
+            // Separate out the number of hours.
+            var hours = 0;
+            if (seconds > 3600) {
+                hours = Math.floor(seconds / 3600);
+                res.push('' + hours + 'h')
+                seconds = seconds % 3600;
+            }
+
+            var d = new Date(1970, 0, 1).setSeconds(seconds);
+
+            if (days == 0) {
+                // Format minutes only if we're within a day of completion.
+                var f = $filter('date')(d, "m'm'");
+                res.push(f);
+            }
+
+            if (days == 0 && hours == 0) {
+                // Format seconds only when we're within an hour of completion.
+                var f = $filter('date')(d, "ss's'");
+                res.push(f);
+            }
+
+            return res.join(' ');
+        }
+
         $scope.deviceStatus = function (deviceCfg) {
             if ($scope.deviceFolders(deviceCfg).length === 0) {
                 return 'unused';