Implement --all option

Implements an "--all" option for the list command
and changes the default behaviour to retireve non
completed tasks only.

src/Todo.CLI/Commands/ListCommand.cs

@@ -11,7 +11,14 @@ public ListCommand(IServiceProvider serviceProvider) : base("list")
         {
             Description = "Retrieves a list of the to do items.";
 
+            AddOption(GetAllOption());
+
             Handler = ListCommandHandler.Create(serviceProvider);
         }
+
+        private Option GetAllOption()
+        {
+            return new Option(new string[] { "-a", "--all" }, "Lists all to do items including the completed ones.");
+        }
     }
 }

src/Todo.CLI/Handlers/ListCommandHandler.cs

@@ -11,10 +11,10 @@ public class ListCommandHandler
     {
         public static ICommandHandler Create(IServiceProvider serviceProvider)
         {
-            return CommandHandler.Create(async () =>
+            return CommandHandler.Create<bool>(async (all) =>
             {
                 var todoItemRetriever = (ITodoItemRepository)serviceProvider.GetService(typeof(ITodoItemRepository));
-                var todoItems = await todoItemRetriever.ListAsync();
+                var todoItems = await todoItemRetriever.ListAsync(all);
                 foreach (var item in todoItems)
                 {
                     Console.WriteLine(item.Subject);

src/Todo.Core/Repository/ITodoItemRepository.cs

@@ -10,6 +10,6 @@ namespace Todo.Core
     public interface ITodoItemRepository
     {
         Task AddAsync(string subject);
-        Task<IEnumerable<TodoItem>> ListAsync();
+        Task<IEnumerable<TodoItem>> ListAsync(bool listAll);
     }
 }

src/Todo.Core/Repository/TodoItemRepository.cs

@@ -5,6 +5,7 @@
 using System.Threading.Tasks;
 using Microsoft.Graph;
 using Todo.Core.Model;
+using TaskStatus = Microsoft.Graph.TaskStatus;
 
 namespace Todo.Core.Repository
 {
@@ -24,10 +25,15 @@ await graphServiceClient.Me.Outlook.Tasks.Request().AddAsync(new OutlookTask()
             });
         }
 
-        public async Task<IEnumerable<TodoItem>> ListAsync()
+        public async Task<IEnumerable<TodoItem>> ListAsync(bool listAll)
         {
             var graphServiceClient = new GraphServiceClient(AuthenticationProvider);
-            var tasks = await graphServiceClient.Me.Outlook.Tasks.Request().GetAsync();
+            var request = graphServiceClient.Me.Outlook.Tasks.Request();
+            if(!listAll)
+            {
+                request.Filter($"status ne '{TaskStatus.Completed.ToString().ToLower()}'");
+            }
+            var tasks = await request.GetAsync();
             return tasks.Select(task => new TodoItem() 
             { 
                 Subject = task.Subject