Add our installer actions

src/Update/Program.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
@@ -7,6 +8,10 @@ using Mono.Options;
 
 namespace Update
 {
+    enum UpdateAction {
+        Unset = 0, Install, Uninstall, Download, Update,
+    }
+
     class Program
     {
         static OptionSet opts;
@@ -19,16 +24,31 @@ namespace Update
                 return 0;
             }
 
+            bool silentInstall = false;
+            var updateAction = default(UpdateAction);
+            string target = default(string);
+
             opts = new OptionSet() {
                 "Usage: Update.exe command [OPTS]",
                 "Manages Squirrel packages",
                 "",
+                "Commands",
+                { "install=", "Install the app specified by the RELEASES file", v => { updateAction = UpdateAction.Install; target = v; } },
+                { "uninstall", "Uninstall the app the same dir as Update.exe", v => updateAction = UpdateAction.Uninstall},
+                { "download=", "Download the releases specified by the URL and write new results to stdout as JSON", v => { updateAction = UpdateAction.Download; target = v; } },
+                { "update", "Update the application to the latest remote version", v => updateAction = UpdateAction.Update },
+                "",
                 "Options:",
-                { "h|?|help", "Display Help and exit", v => ShowHelp() }
+                { "h|?|help", "Display Help and exit", _ => ShowHelp() },
+                { "s|silent", "Silent install", _ => silentInstall = true},
             };
 
             opts.Parse(args);
 
+            if (updateAction == UpdateAction.Unset) {
+                ShowHelp();
+            }
+
             return 0;
         }