CommandTerminal_Should

using FluentAssertions;
using NSubstitute;
using NUnit.Framework;

namespace CommandSystem
{
    [TestFixture]
    public class CommandTerminalShould
    {
        private CommandTerminal _terminal;

        private TerminalDisplay _display;
        private TerminalCommands _commands;
        private Command _commandA;

        [SetUp]
        public void Setup()
        {
            _commandA = Substitute.For<Command>();
            _display = Substitute.For<TerminalDisplay>();
            _commands = Substitute.For<TerminalCommands>();



            _terminal = new CommandTerminal(_display,_commands);


        }

        [Test]
        public void when_no_commands_send_messages_to_display()
        {
            ReturnNoCommands();

            var message = "Hello World";
            string sender = "Jason";
            _terminal.Enter(sender, message);
            _display.Received().Send(sender,message);
        }

        [Test]
        public void when_command_matched_execute_command()
        {
            ReturnCommand(_commandA);

            var message = "Execute Order 66";
            string sender = "Jason";
            _terminal.Enter(sender,message);

            _commandA.Received().Execute();
        }

        [Test]
        public void When_default_sender_empty_sender_is_system()
        {
            ReturnNoCommands();

            _terminal.Enter("Message");
            _display.Received().Send("SYSTEM", "Message");
        }

        [Test]
        public void when_default_sender_assigned_returns_default_sender()
        {
            ReturnNoCommands();

            const string DEFAULT_SENDER = "DEFAULT_SENDER";
            _terminal.SetDefaultSender(DEFAULT_SENDER);

            _terminal.Enter("TEST");

            _display.Received().Send(DEFAULT_SENDER,"TEST");

        }

        [Test]
        public void use_provided_command()
        {
            ReturnCommand(_commandA);

            var commander = new Commander();

            _terminal = new CommandTerminal(commander,_display,_commands);

            _terminal.Commander.Should().Be(commander);


            _terminal.Enter(string.Empty);

            _commandA.Received().Execute();


        }


        void ReturnNoCommands()=>ReturnCommand(NoCommand.Instance);
        void ReturnCommand(Command cmd)
        {
            _commands.FindCommandFor(Arg.Any<string>())
                .ReturnsForAnyArgs(cmd);
        }
    }
}