Adventure.cs

using System;
using System.Linq;

namespace Adventure
{
    internal class Program
    {
        private static Game _game;

        private static void Main(string[] args)
        {
            Console.Title = $"Welcome to Camelot.";
            _game = new Game();
            Start();
        }

        public static void Start()
        {
            _game.Reset();
            Room1();
            Console.Clear();
            _game.Say("Your game has ended.");
            Console.ReadKey();
            Start();
        }

        private static void Room1()
        {
            _game.Say("You have entered a green room.", ConsoleColor.White, ConsoleColor.Green);
            _game.Doors(Room2, Room3, Room4);
        }

        private static void Room2()
        {
            _game.Say("You have entered a red room.", ConsoleColor.White, ConsoleColor.Red);
            if (_game.Monster(10, "Monster"))
            {
                _game.Doors(Room3, Room4, Room5);
            }
        }

        private static void Room3()
        {
            _game.Say("You have entered a brown room.", ConsoleColor.White, ConsoleColor.DarkYellow);
            _game.Treasure("You have discovered a refreshing fountain.", 10);
            _game.Doors(Room4, Room5, Room1);
        }

        private static void Room4()
        {
            _game.Say("You have entered a blue room.", ConsoleColor.White, ConsoleColor.Blue);
            if (_game.Monster(10, "Dragon"))
            {
                _game.Treasure("The dragon's mouth contains treasure.", 20);
                _game.Doors(Room3, Room5);
            }
        }

        private static void Room5()
        {
            _game.Say("You have entered a blue room.", ConsoleColor.White, ConsoleColor.Blue);
            if (_game.Monster(10, "Dragon"))
            {
                _game.Doors(Room3, Room5);
            }
        }
    }

    internal class Game
    {
        private readonly Random _random = new Random();

        public bool GameOver => Life == 0;
        public int Life;
        public int Score;

        public void Reset()
        {
            Life = 100;
            Score = 0;
        }

        public void Treasure(string text, int value, ConsoleColor foreground = ConsoleColor.Green, ConsoleColor background = ConsoleColor.DarkGray)
        {
            Say(text, foreground, background);
            Say($"Your life has increased to {value}.", foreground, background);
            Life = Life + value;
            PrintInformation();
        }

        public void PrintInformation(ConsoleColor foreground = ConsoleColor.White, ConsoleColor background = ConsoleColor.DarkGray)
        {
            Say($"Your life {Life}. Your score {Score}", foreground, background);
        }

        public void Doors(params Action[] actions)
        {
            Say($"{Environment.NewLine}There are {actions.Count()} doors.");

            var doors = Enumerable.Range(1, actions.Count()).Select(x => $"Door number {x}").ToArray();
            var door = Choose("Which do you choose?", doors);

            Say($"You have chosen door number {(int)door}{Environment.NewLine}");
            actions[(int)door - 1].Invoke();
        }

        public bool Monster(int monster, string kind)
        {
            Console.Clear();

            Say($"There is an angry {kind} in the room.", ConsoleColor.Red, ConsoleColor.White);
            Say($"You have {Life} life. The {kind} has {monster}.", ConsoleColor.Black, ConsoleColor.White);

            var answer = Choose($"Choose your weapon to attach the {kind}.",
                "Your dangerous fist (2 point at risk)",
                "Your enchanged hammer (4 points at risk)",
                "Your magical sword (6 points at risk)");

            var victory = _random.NextDouble() >= 0.5;

            if (victory)
            {
                monster = Math.Max(monster - (int)answer * 2, 0);
                Say($"You strike the {kind}. His life is now {monster}.", ConsoleColor.Green);
            }
            else
            {
                Life = Math.Max(Life - (int)answer * 2, 0);
                Say($"The {kind} hits you. Your life is now {Life}.", ConsoleColor.Red);
            }

            if (monster == 0)
            {
                Say($"You have been victorious against the {kind}.", ConsoleColor.Green);
                Console.ReadKey(true);
                return true;
            }
            else if (Life == 0)
            {
                Say($"You have been defeated by the {kind}.", ConsoleColor.Red);
                Console.ReadKey(true);
                return false;
            }
            else
            {
                Console.ReadKey(true);
                return Monster(monster, kind);
            }
        }

        public bool GetRandomTrueFalse()
        {
            return _random.NextDouble() >= 0.5;
        }

        public void Say(string text, ConsoleColor foreground = ConsoleColor.White, ConsoleColor background = ConsoleColor.Black)
        {
            Console.ForegroundColor = foreground;
            Console.BackgroundColor = background;
            Console.WriteLine(text);
            Console.ResetColor();
        }

        public Answer Choose(string text, params string[] options)
        {
            return Choose(text, ConsoleColor.White, ConsoleColor.Black, options);
        }

        public Answer Choose(string text, ConsoleColor foreground = ConsoleColor.White, ConsoleColor background = ConsoleColor.Black, params string[] options)
        {
            Console.ForegroundColor = foreground;
            Console.BackgroundColor = background;
            Console.WriteLine(text);
            Console.ResetColor();

            foreach (var item in options.Select((x, i) => new { Index = (Answer)(i + 1), Text = x }))
            {
                Console.WriteLine($"{item.Index}. {item.Text}");
            }

            var character = Console.ReadKey(true).KeyChar.ToString().ToUpper();

            // what if they typed a number that could work?
            if (int.TryParse(character, out var number) && number <= options.Count())
            {
                return (Answer)number;
            }

            // can we parse they character to the enum?
            if (!Enum.TryParse<Answer>(character, out var result))
            {
                return TryAgain();
            }

            // is the enum inside the possible options?
            if ((int)result > options.Count())
            {
                return TryAgain();
            }

            // looks good
            return result;

            Answer TryAgain()
            {
                while (Console.KeyAvailable)
                {
                    Console.ReadKey(true);
                }
                Say("Please try again.", ConsoleColor.Yellow, ConsoleColor.Blue);
                return Choose(text, foreground, background, options);
            }
        }

        public string Ask(string text, ConsoleColor foreground = ConsoleColor.White, ConsoleColor background = ConsoleColor.Black)
        {
            Console.ForegroundColor = foreground;
            Console.BackgroundColor = background;
            Console.WriteLine();
            Console.ResetColor();
            return Console.ReadLine();
        }

        public ConsoleKey ReadKey()
        {
            if (Console.KeyAvailable)
            {
                return Console.ReadKey(true).Key;
            }
            else
            {
                return default(ConsoleKey);
            }
        }

        public char ReadChar()
        {
            if (Console.KeyAvailable)
            {
                return Console.ReadKey(true).KeyChar;
            }
            else
            {
                return default(char);
            }
        }
    }

    public enum Answer : int { None = 0, A = 1, B = 2, C = 3, D = 4, E = 5, F = 6, G = 7, H = 8, I = 9 }
}