Add remaining scanning time (fixes #2484)

gui/assets/lang/lang-en.json

@@ -138,6 +138,7 @@
    "Resume": "Resume",
    "Reused": "Reused",
    "Save": "Save",
+   "Scan Time Remaining": "Scan Time Remaining",
    "Scanning": "Scanning",
    "Select the devices to share this folder with.": "Select the devices to share this folder with.",
    "Select the folders to share with this device.": "Select the folders to share with this device.",

gui/index.html

@@ -228,7 +228,7 @@
                   <span ng-switch-when="scanning">
                     <span class="hidden-xs" translate>Scanning</span>
                     <span class="hidden-xs" ng-if="scanPercentage(folder.id) != undefined">
-                      (<span class="hidden-xs" ng-if="scanRate(folder.id) > 0">{{scanRate(folder.id) | binary}}B/s, </span>{{scanPercentage(folder.id)}}%)
+                      {{scanPercentage(folder.id)}}%
                     </span>
                     <span class="visible-xs">&#9724;</span>
                   </span>
@@ -267,6 +267,12 @@
                         <a href="" ng-click="showNeed(folder.id)">{{model[folder.id].needFiles | alwaysNumber}} <span translate>items</span>, ~{{model[folder.id].needBytes | binary}}B</a>
                       </td>
                     </tr>
+                    <tr ng-if="folderStatus(folder) === 'scanning' && scanRate(folder.id) > 0">
+                      <th><span class="fa fa-fw fa-hourglass-2"></span>&nbsp;<span translate>Scan Time Remaining</span></th>
+                      <td class="text-right">
+                        <span title="{{scanRate(folder.id) | binary}}B/s">~ {{scanRemaining(folder.id)}}</span>
+                      </td>
+                    </tr>
                     <tr ng-if="!folder.readOnly && (folderStatus(folder) === 'outofsync' || hasFailedFiles(folder.id))">
                       <th><span class="fa fa-fw fa-exclamation-circle"></span>&nbsp;<span translate>Failed Items</span></th>
                       <!-- Show the number of failed items as a link to bring up the list. -->

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';

lib/scanner/walk.go

@@ -146,9 +146,6 @@ func (w *Walker) Walk() (chan protocol.FileInfo, error) {
 		var filesToHash []protocol.FileInfo
 		var total int64 = 1
 
-		progress := newByteCounter()
-		defer progress.Close()
-
 		for file := range toHashChan {
 			filesToHash = append(filesToHash, file)
 			total += int64(file.CachedSize)
@@ -156,6 +153,9 @@ func (w *Walker) Walk() (chan protocol.FileInfo, error) {
 
 		realToHashChan := make(chan protocol.FileInfo)
 		done := make(chan struct{})
+		progress := newByteCounter()
+		defer progress.Close()
+
 		newParallelHasher(w.Dir, w.BlockSize, w.Hashers, finishedChan, realToHashChan, progress, done, w.Cancel)
 
 		// A routine which actually emits the FolderScanProgress events