Derive User classes directly from IUser interface instead of the NullUser class.

Cmdline/ConsoleUser.cs

@@ -4,32 +4,44 @@
 
 namespace CKAN.CmdLine
 {
-    public class ConsoleUser : NullUser
+    /// <summary>
+    /// The commandline implementation of the IUser interface.
+    /// </summary>
+    public class ConsoleUser : IUser
     {
+        /// <summary>
+        /// A logger for this class.
+        /// ONLY FOR INTERNAL USE!
+        /// </summary>
         private static readonly ILog log = LogManager.GetLogger(typeof(ConsoleUser));
 
-        private bool m_Headless = false;
-        public ConsoleUser(bool headless)
+        /// <summary>
+        /// Initializes a new instance of the <see cref="T:CKAN.CmdLine.ConsoleUser"/> class.
+        /// </summary>
+        /// <param name="headless">If set to <c>true</c>, supress interactive dialogs like Yes/No-Dialog or SelectionDialog.</param>
+        public ConsoleUser (bool headless)
         {
-            m_Headless = headless;
+            Headless = headless;
         }
 
-        public override bool Headless
+        /// <summary>
+        /// Gets a value indicating whether this <see cref="T:CKAN.CmdLine.ConsoleUser"/> is headless.
+        /// </summary>
+        /// <value><c>true</c> if headless; otherwise, <c>false</c>.</value>
+        public bool Headless { get; }
+
+        /// <summary>
+        /// Ask the user for a yes or no input.
+        /// </summary>
+        /// <param name="question">Question.</param>
+        public bool RaiseYesNoDialog(string question)
         {
-            get
-            {
-                return m_Headless;
-            }
-        }
-
-        protected override bool DisplayYesNoDialog(string message)
-        {
-            if (m_Headless)
+            if (Headless)
             {
                 return true;
             }
 
-            Console.Write("{0} [Y/n] ", message);
+            Console.Write("{0} [Y/n] ", question);
             while (true)
             {
                 var input = Console.In.ReadLine();
@@ -60,22 +72,20 @@ protected override bool DisplayYesNoDialog(string message)
             }
         }
 
-        protected override void DisplayMessage(string message, params object[] args)
-        {
-            Console.WriteLine(message, args);
-        }
-
-        protected override void DisplayError(string message, params object[] args)
-        {
-            Console.Error.WriteLine(message, args);
-        }
-
-        protected override int DisplaySelectionDialog(string message, params object[] args)
+        /// <summary>
+        /// Ask the user to select one of the elements of the array.
+        /// The output is index 0 based.
+        /// To supply a default option, make the first option an integer indicating the index of it.
+        /// </summary>
+        /// <returns>The selection dialog.</returns>
+        /// <param name="message">Message.</param>
+        /// <param name="args">Array of available options.</param>
+        public int RaiseSelectionDialog(string message, params object[] args)
         {
             const int return_cancel = -1;
 
             // Check for the headless flag.
-            if (m_Headless)
+            if (Headless)
             {
                 // Return that the user cancelled the selection process.
                 return return_cancel;
@@ -227,17 +237,33 @@ protected override int DisplaySelectionDialog(string message, params object[] ar
             return result;
         }
 
-        protected override void ReportProgress(string format, int percent)
+        /// <summary>
+        /// Write an error to the console.
+        /// </summary>
+        /// <param name="message">Message.</param>
+        /// <param name="args">Possible arguments to format the message.</param>
+        public void RaiseError(string message, params object[] args)
+        {
+            Console.Error.WriteLine(message, args);
+        }
+
+        /// <summary>
+        /// Write a progress message including the percentage to the console.
+        /// Rewrites the line, so the console is not cluttered by progress messages.
+        /// </summary>
+        /// <param name="message">Message.</param>
+        /// <param name="percent">Progress in percent.</param>
+        public void RaiseProgress(string message, int percent)
         {
-            if (Regex.IsMatch(format, "download", RegexOptions.IgnoreCase))
+            if (Regex.IsMatch(message, "download", RegexOptions.IgnoreCase))
             {
                 // In headless mode, only print a new message if the percent has changed,
                 // to reduce clutter in Jenkins for large downloads
-                if (!m_Headless || percent != previousPercent)
+                if (!Headless || percent != previousPercent)
                 {
                     // The \r at the front here causes download messages to *overwrite* each other.
                     Console.Write(
-                        "\r{0} - {1}%           ", format, percent);
+                        "\r{0} - {1}%           ", message, percent);
                     previousPercent = percent;
                 }
             }
@@ -246,10 +272,23 @@ protected override void ReportProgress(string format, int percent)
                 // The percent looks weird on non-download messages.
                 // The leading newline makes sure we don't end up with a mess from previous
                 // download messages.
-                Console.Write("\r\n{0}", format);
+                Console.Write("\r\n{0}", message);
             }
         }
 
+        /// <summary>
+        /// Needed for <see cref="RaiseProgress(string, int)"/>
+        /// </summary>
         private int previousPercent = -1;
+
+        /// <summary>
+        /// Writes a message to the console.
+        /// </summary>
+        /// <param name="message">Message.</param>
+        /// <param name="args">Arguments to format the message.</param>
+        public void RaiseMessage(string message, params object[] args)
+        {
+            Console.WriteLine(message, args);
+        }
     }
 }

ConsoleUI/Toolkit/ConsoleScreen.cs

@@ -72,7 +72,7 @@ protected virtual string MenuTip()
         /// </summary>
         protected ConsolePopupMenu mainMenu = null;
 
-        // IUser
+        #region IUser
 
         /// <summary>
         /// Tell IUser clients that we have the ability to interact with the user
@@ -207,7 +207,7 @@ public void RaiseProgress(string message, int percent)
         /// <param name="percent">Value from 0 to 100 representing task completion</param>
         protected virtual void Progress(string message, int percent) { }
 
-        // End IUser
+        #endregion IUser
 
         private void DrawSelectedHamburger()
         {

Core/ModuleInstaller.cs

@@ -177,7 +177,15 @@ public void InstallList(ICollection<CkanModule> modules, RelationshipResolverOpt
                 }
             }
 
-            bool ok = User.RaiseYesNoDialog("\r\nContinue?");
+            bool ok;
+            if (User.GetType().ToString() == "CKAN.GUIUser")
+            {
+                ok = true;
+            }
+            else
+            {
+                ok = User.RaiseYesNoDialog("\r\nContinue?");
+            }
 
             if (!ok)
             {
@@ -770,7 +778,15 @@ public void UninstallList(IEnumerable<string> mods)
                 User.RaiseMessage(" * {0} {1}", module.Module.name, module.Module.version);
             }
 
-            bool ok = User.RaiseYesNoDialog("\r\nContinue?");
+            bool ok;
+            if (User.GetType().ToString() == "CKAN.GUIUser")
+            {
+                ok = true;
+            }
+            else
+            {
+                ok = User.RaiseYesNoDialog("\r\nContinue?");
+            }
 
             if (!ok)
             {

Core/User.cs

@@ -1,9 +1,10 @@
-// Communicate with the user (status messages, yes/no questions, etc)
-// This class will proxy to either the GUI or cmdline functionality.
-
 namespace CKAN
 {
-
+    /// <summary>
+    /// This interface holds all methods which communicate with the user in some way.
+    /// Every CKAN interface (GUI, cmdline, consoleUI) has an implementation of the IUser interface.
+    /// The implementations define HOW we interact with the user.
+    /// </summary>
     public interface IUser
     {
         bool Headless { get; }
@@ -13,68 +14,46 @@ public interface IUser
         void RaiseError(string message, params object[] args);
 
         void RaiseProgress(string message, int percent);
-        void RaiseMessage(string message, params object[] url);
+        void RaiseMessage(string message, params object[] args);
     }
 
-    //Can be used in tests to supress output or as a base class for other types of user.
-    //It supplies no op event handlers so that subclasses can avoid null checks.
+    /// <summary>
+    /// To be used in tests.
+    /// Supresses all output.
+    /// </summary>
     public class NullUser : IUser
     {
         public static readonly IUser User = new NullUser();
 
-        public NullUser() { }
-
         public virtual bool Headless
         {
             get { return false; }
         }
 
-        protected virtual bool DisplayYesNoDialog(string message)
-        {
-            return true;
-        }
-
-        protected virtual int DisplaySelectionDialog(string message, params object[] args)
-        {
-            return 0;
-        }
-
-        protected virtual void DisplayError(string message, params object[] args)
-        {
-        }
-
-        protected virtual void ReportProgress(string format, int percent)
-        {
-        }
-
         protected virtual void DisplayMessage(string message, params object[] args)
         {
         }
 
         public bool RaiseYesNoDialog(string question)
         {
-            return DisplayYesNoDialog(question);
+            return true;
         }
 
         public int RaiseSelectionDialog(string message, params object[] args)
         {
-            return DisplaySelectionDialog(message, args);
+            return 0;
         }
 
         public void RaiseError(string message, params object[] args)
         {
-            DisplayError(message, args);
         }
 
         public void RaiseProgress(string message, int percent)
         {
-            ReportProgress(message, percent);
         }
 
         public void RaiseMessage(string message, params object[] args)
         {
-            DisplayMessage(message, args);
         }
-
     }
 }

GUI/CKAN-GUI.csproj

@@ -238,6 +238,8 @@
       <DependentUpon>YesNoDialog.cs</DependentUpon>
     </Compile>
     <Compile Include="TransparentTextBox.cs" />
+    <Compile Include="SelectionDialog.cs" />
+    <Compile Include="SelectionDialog.Designer.cs" />
   </ItemGroup>
   <ItemGroup>
     <EmbeddedResource Include="AboutDialog.resx">
@@ -302,6 +304,7 @@
       <Generator>SettingsSingleFileGenerator</Generator>
       <LastGenOutput>Settings.Designer.cs</LastGenOutput>
     </None>
+    <None Include="SelectionDialog.resx" />
   </ItemGroup>
   <ItemGroup>
     <BootstrapperPackage Include=".NETFramework,Version=v4.0">

GUI/ChooseKSPInstance.cs

@@ -87,7 +87,7 @@ private void AddNewButton_Click(object sender, EventArgs e)
             }
             catch (NotKSPDirKraken k)
             {
-                GUI.user.displayError("Directory {0} is not valid KSP directory.",
+                GUI.user.RaiseError("Directory {0} is not valid KSP directory.",
                     new object[] { k.path });
                 return;
             }
@@ -125,7 +125,7 @@ private void UseSelectedInstance()
             }
             catch (NotKSPDirKraken k)
             {
-                GUI.user.displayError("Directory {0} is not valid KSP directory.",
+                GUI.user.RaiseError("Directory {0} is not valid KSP directory.",
                     new object[] { k.path });
             }
         }