Manipulate the captcha callback, so no longer a seccond App is required.

Signal-Windows/ViewModels/CaptchaPageViewModel.cs

@@ -40,5 +40,13 @@ private void BackButton_Click(object sender, BackRequestedEventArgs e)
             View.Frame.GoBack();
             e.Handled = true;
         }
+
+        public void SetToken(string signalCaptchaToken)
+        {
+            var registerPageInstance = App.CurrentSignalWindowsFrontend(App.MainViewId).Locator.RegisterPageInstance;
+            registerPageInstance.CaptchaCode = signalCaptchaToken;
+            registerPageInstance.CaptchaWebViewEnabled = false;
+            App.CurrentSignalWindowsFrontend(App.MainViewId).Locator.CaptchaPageInstance.View.Frame.GoBack();
+        }
     }
 }

Signal-Windows/Views/CaptchaPage.xaml

@@ -2,18 +2,26 @@
     x:Class="Signal_Windows.Views.CaptchaPage"
     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-    xmlns:local="using:Signal_Windows.Views"
     xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+    xmlns:local="using:Signal_Windows.Views"
     xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
-    mc:Ignorable="d"
-    DataContext="{Binding CaptchaPageInstance, Source={StaticResource Locator}}">
+    DataContext="{Binding CaptchaPageInstance, Source={StaticResource Locator}}"
+    mc:Ignorable="d">
 
     <Grid>
-        <WebView x:Name="webView" Source="{x:Bind Vm.WebViewSource, Mode=TwoWay}"/>
-        <Button x:Name="refreshButton" VerticalAlignment="Bottom" HorizontalAlignment="Center" Click="refreshButton_Click">
+        <WebView
+            x:Name="webView"
+            NavigationStarting="webView_NavigationStarting"
+            NavigationCompleted="webView_NavigationCompleted"
+            Source="{x:Bind Vm.WebViewSource, Mode=TwoWay}" />
+        <Button
+            x:Name="refreshButton"
+            HorizontalAlignment="Center"
+            VerticalAlignment="Bottom"
+            Click="refreshButton_Click">
             <StackPanel Orientation="Horizontal">
-                <SymbolIcon Symbol="Refresh"/>
-                <TextBlock Text="Refresh" Margin="8,0,0,0"/>
+                <SymbolIcon Symbol="Refresh" />
+                <TextBlock Margin="8,0,0,0" Text="Refresh" />
             </StackPanel>
         </Button>
     </Grid>

Signal-Windows/Views/CaptchaPage.xaml.cs

@@ -54,5 +54,24 @@ private void refreshButton_Click(object sender, RoutedEventArgs e)
             // KeyDown event doesn't work with WebView so just use a button to allow users to refresh the page
             webView.Refresh();
         }
+
+        private void webView_NavigationStarting(WebView sender, WebViewNavigationStartingEventArgs args)
+        {
+            if (args.Uri.ToString().StartsWith("http://token/"))
+            {
+                args.Cancel = true;
+                var token = args.Uri.ToString().Substring("http://token/".Length);
+                Vm.SetToken(token);
+            }
+        }
+
+        private async void webView_NavigationCompleted(WebView sender, WebViewNavigationCompletedEventArgs args)
+        {
+            var result = await sender.InvokeScriptAsync("eval", new[] { "document.getElementsByTagName('html')[0].innerHTML;" });
+            if (result.Contains("\"signalcaptcha://\"") && result.Contains("function onToken(token)"))
+            {
+                await sender.InvokeScriptAsync("eval", new[] { @"function onToken(token) { window.location = ""http://Token/"" + token; }" });
+            }
+        }
     }
 }