Initial commit

CommandHandler/Navigation/States/NavigationMainState.cs

@@ -0,0 +1,12 @@
+using CommandHandler.Commands;
+
+namespace CommandHandler.Navigation.States;
+
+internal class NavigationMainState : NavigationStateBase, INavigationDrawer
+{
+    public NavigationMainState()
+    {
+        Commands.Add("/some", () => ChangeNavigationState(new NavigationSomeState()));
+        Commands.Add("/exit", () => new ExitCommand());
+    }
+}

CommandHandler/Navigation/States/NavigationSomeState.cs

@@ -0,0 +1,9 @@
+namespace CommandHandler.Navigation.States;
+
+internal class NavigationSomeState : NavigationStateBase, INavigationDrawer
+{
+    public NavigationSomeState()
+    {
+        Commands.Add("/back", () => ChangeNavigationState(new NavigationMainState()));
+    }
+}

CommandHandler/Navigation/States/NavigationStateBase.cs

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+using System.Text;
+using CommandHandler.Commands;
+
+namespace CommandHandler.Navigation.States;
+
+internal abstract class NavigationStateBase : INavigationState, INavigationDrawer
+{
+    private INavigationContext? _context;
+
+    protected readonly IDictionary<string, Func<ICommand>> Commands = new Dictionary<string, Func<ICommand>>();
+
+    protected ICommand ChangeNavigationState(INavigationState  newState)
+    {
+        if (_context == null)
+        {
+            throw new InvalidOperationException();
+        }
+
+        var commands = new List<ICommand>
+        {
+            new ChangeNavigationStateCommand(_context, newState)
+        };
+
+        if (newState is INavigationDrawer drawer)
+        {
+            commands.Add(new DrawMenuCommand(drawer));
+        }
+
+        return new CombinedCommand([.. commands]);
+    }
+
+    public void SetContext(INavigationContext context)
+    {
+        _context = context;
+    }
+
+    public ICommand GetCommand(string message)
+    {
+        var parts = message.Split(' ', StringSplitOptions.RemoveEmptyEntries);
+        if (parts.Length <= 0)
+        {
+            return new EmptyCommand();
+        }
+
+        if (Commands.TryGetValue(parts[0], out var commandFactory))
+        {
+            return commandFactory();
+        }
+
+        if (this is INavigationDrawer navigationDrawer)
+        {
+            return new DrawMenuCommand(navigationDrawer);
+        }
+
+        throw new NotImplementedException();
+    }
+
+    public string DrawNavigationMenu()
+    {
+        var builder = new StringBuilder();
+
+        foreach (var command in Commands.Keys)
+        {
+            builder.AppendLine(command);
+        }
+
+        return builder.ToString();
+    }
+}