Autocomplete

TaskRunner/CommandReader.cs

@@ -0,0 +1,66 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace TaskRunner
+{
+    internal class CommandReader
+    {
+        private readonly ITaskLibrary taskLibrary;
+        private string buffer;
+
+        internal CommandReader(ITaskLibrary TaskLibrary)
+        {
+            taskLibrary = TaskLibrary;
+        }
+
+        internal string GetCommand()
+        {
+            buffer = string.Empty;
+            while (true)
+            {
+                ConsoleKeyInfo keyInfo = Console.ReadKey(true);
+
+                switch (keyInfo.Key)
+                {
+                    case ConsoleKey.Backspace:
+                        RemoveChar(1);
+                        break;
+                    case ConsoleKey.Tab:
+                        string offer = taskLibrary.OfferTaskName(buffer, 0);
+                        if (string.IsNullOrEmpty(offer))
+                        {
+                            Console.Beep();
+                        }
+                        else
+                        {
+                            RemoveChar(int.MaxValue);
+                            Console.Write(offer);
+                            buffer = offer;
+                        }
+                        break;
+                    case ConsoleKey.Enter:
+                        Console.WriteLine();
+                        return buffer;
+                        break;
+                    default:
+                        if (char.IsLetterOrDigit(keyInfo.KeyChar) || char.IsPunctuation(keyInfo.KeyChar))
+                        {
+                            buffer += keyInfo.KeyChar;
+                            Console.Write(keyInfo.KeyChar);
+                        }
+                        break;
+                }
+            }
+        }
+
+        private void RemoveChar(int count)
+        {
+            int countToRemove = count < buffer.Length ? count : buffer.Length;
+            buffer = buffer.Remove(buffer.Length - countToRemove);
+            string display = string.Concat(new string('\b',countToRemove), new string(' ',countToRemove), new string('\b',countToRemove));
+            Console.Write(display);
+        }
+    }
+}

TaskRunner/ITaskLibrary.cs

@@ -6,5 +6,6 @@ internal interface ITaskLibrary
     {
         void RunTask(string name);
         ReadOnlyCollection<TaskInformation> Tasks();
+        string OfferTaskName(string partial, int offerIndex);
     }
 }

TaskRunner/Runner.cs

@@ -6,9 +6,11 @@ namespace TaskRunner
     public class Runner
     {
         private readonly ITaskLibrary taskLibrary;
+        private CommandReader commandReader;
         public Runner()
         {
             taskLibrary = new TaskLibrary();
+            commandReader = new CommandReader(taskLibrary);
         }
 
         public void Go()
@@ -18,10 +20,12 @@ public void Go()
 
         private void SayHello()
         {
-            Console.WriteLine("Welcome to the TaskRunner. Type 'list' to see a list of available tasks to run. Type the name of task to run it or type 'exit' to close the TaskRunner.");
-
+            Console.WriteLine("Welcome to the TaskRunner. Type 'list' to see a list of available tasks to run.");
+            Console.WriteLine("Type the name of task to run it or type 'exit' to close the TaskRunner.");
+            Console.WriteLine("Task names have auto complete feature type part of the name and hit [TAB].");
+            Console.WriteLine("");
             Console.Write(" > ");
-            var command = Console.ReadLine();
+            var command = commandReader.GetCommand();
             TakeAction(command);
         }
 
@@ -58,8 +62,10 @@ private void TakeAction(string command)
             Console.WriteLine();
             Console.WriteLine("Task '{0}' executed. What's next?", command);
             Console.Write(" > ");
-            var newCommand = Console.ReadLine();
+            var newCommand = commandReader.GetCommand();
             TakeAction(newCommand);
         }
+
+
     }
 }

TaskRunner/TaskLibrary.cs

@@ -8,12 +8,14 @@ namespace TaskRunner
     internal class TaskLibrary : ITaskLibrary
     {
         private readonly List<TaskInformation> tasks;
+        private readonly List<string> taskNames;
         private readonly ITaskLoader taskLoader;
 
         public TaskLibrary()
         {
             taskLoader = new TaskLoader();
             tasks = taskLoader.FindTasks();
+            taskNames = (from task in tasks select task.Name).ToList();
         }
 
         public void RunTask(string name)
@@ -32,5 +34,12 @@ public ReadOnlyCollection<TaskInformation> Tasks()
         {
             return tasks.AsReadOnly();
         }
+
+        public string OfferTaskName(string partial, int offerIndex)
+        {
+            return (from name in taskNames
+                    where name.ToLowerInvariant().Contains(partial.ToLowerInvariant())
+                    select name).ElementAtOrDefault(offerIndex);            
+        }
     }
 }

TaskRunner/TaskRunner.csproj

@@ -40,6 +40,7 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="CommandReader.cs" />
     <Compile Include="ITask.cs" />
     <Compile Include="ITaskLibrary.cs" />
     <Compile Include="ITaskLoader.cs" />