Implement add command

src/Todo.CLI/Commands/AddCommand.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Collections.Generic;
+using System.CommandLine;
+using System.Text;
+using Todo.CLI.Handlers;
+
+namespace Todo.CLI.Commands
+{
+    public class AddCommand : Command
+    {
+        public AddCommand(IServiceProvider serviceProvider) : base("add")
+        {
+            Description = "Adds a to do item.";
+
+            AddArgument(GetSubjectArgument());
+
+            Handler = AddCommandHandler.Create(serviceProvider);
+        }
+
+        private Argument GetSubjectArgument()
+        {
+            return new Argument("subject")
+            {
+                Description = "The subject of the new to do item.",
+                ArgumentType = typeof(string)
+            };
+        }
+    }
+}

src/Todo.CLI/Commands/TodoCommand.cs

@@ -21,6 +21,7 @@ public TodoCommand(IServiceProvider serviceProvider)
             Handler = TodoCommandHandler.Create();
 
             // Add subcommands
+            AddCommand(new AddCommand(serviceProvider));
             AddCommand(new ListCommand(serviceProvider));
         }
 

src/Todo.CLI/Handlers/AddCommandHandler.cs

@@ -0,0 +1,21 @@
+using System;
+using System.CommandLine;
+using System.CommandLine.Invocation;
+using System.IO;
+using System.Reflection;
+using Todo.Core;
+
+namespace Todo.CLI.Handlers
+{
+    public class AddCommandHandler
+    {
+        public static ICommandHandler Create(IServiceProvider serviceProvider)
+        {
+            return CommandHandler.Create<string>(async (subject) =>
+            {
+                var todoItemRepository = (ITodoItemRepository)serviceProvider.GetService(typeof(ITodoItemRepository));
+                await todoItemRepository.AddAsync(subject);
+            });
+        }
+    }
+}

src/Todo.CLI/appsettings.json

@@ -3,7 +3,7 @@
     "ClientId": "5c594999-30b1-4a68-afcf-56ce11715b4d",
     "Scopes": [
       "user.read",
-      "tasks.read"
+      "tasks.readwrite"
     ]
   }
 }

src/Todo.Core/Repository/ITodoItemRepository.cs

@@ -9,6 +9,7 @@ namespace Todo.Core
 {
     public interface ITodoItemRepository
     {
+        Task AddAsync(string subject);
         Task<IEnumerable<TodoItem>> ListAsync();
     }
 }

src/Todo.Core/Repository/TodoItemRepository.cs

@@ -15,6 +15,15 @@ public TodoItemRepository(IAuthenticationProvider authenticationProvider)
         {
         }
 
+        public async Task AddAsync(string subject)
+        {
+            var graphServiceClient = new GraphServiceClient(AuthenticationProvider);
+            await graphServiceClient.Me.Outlook.Tasks.Request().AddAsync(new OutlookTask()
+            {
+                Subject = subject
+            });
+        }
+
         public async Task<IEnumerable<TodoItem>> ListAsync()
         {
             var graphServiceClient = new GraphServiceClient(AuthenticationProvider);