Merge pull request #250 from drewjcooper/84-super-star-trek-csharp

84 super star trek - C#

84 Super Star Trek/csharp/Commands/Command.cs

@@ -1,6 +1,6 @@
 using System.ComponentModel;
 
-namespace SuperStarTrek
+namespace SuperStarTrek.Commands
 {
     internal enum Command
     {

84 Super Star Trek/csharp/Commands/CommandExtensions.cs

@@ -1,7 +1,7 @@
 using System.Reflection;
 using System.ComponentModel;
 
-namespace SuperStarTrek
+namespace SuperStarTrek.Commands
 {
     internal static class CommandExtensions
     {

84 Super Star Trek/csharp/Commands/CommandResult.cs

@@ -0,0 +1,23 @@
+namespace SuperStarTrek.Commands
+{
+    internal class CommandResult
+    {
+        public static readonly CommandResult Ok = new(false);
+        public static readonly CommandResult GameOver = new(true);
+
+        private CommandResult(bool isGameOver)
+        {
+            IsGameOver = isGameOver;
+        }
+
+        private CommandResult(float timeElapsed)
+        {
+            TimeElapsed = timeElapsed;
+        }
+
+        public bool IsGameOver { get; }
+        public float TimeElapsed { get; }
+
+        public static CommandResult Elapsed(float timeElapsed) => new(timeElapsed);
+    }
+}

84 Super Star Trek/csharp/Game.cs

@@ -3,6 +3,7 @@ using SuperStarTrek.Objects;
 using SuperStarTrek.Resources;
 using SuperStarTrek.Space;
 using SuperStarTrek.Systems;
+using SuperStarTrek.Systems.ComputerFunctions;
 using static System.StringComparison;
 
 namespace SuperStarTrek
@@ -11,12 +12,12 @@ namespace SuperStarTrek
     {
         private readonly Output _output;
         private readonly Input _input;
+        private readonly Random _random;
 
         private int _initialStardate;
         private int _finalStarDate;
-        private double _currentStardate;
+        private float _currentStardate;
         private Coordinates _currentQuadrant;
-        private Coordinates _currentSector;
         private Galaxy _galaxy;
         private int _initialKlingonCount;
         private Enterprise _enterprise;
@@ -25,19 +26,17 @@ namespace SuperStarTrek
         {
             _output = new Output();
             _input = new Input(_output);
+            _random = new Random();
         }
 
-        public double Stardate => _currentStardate;
+        public float Stardate => _currentStardate;
+        public float StardatesRemaining => _finalStarDate - _currentStardate;
 
         public void DoIntroduction()
         {
             _output.Write(Strings.Title);
 
-            _output.Write("Do you need instructions (Y/N)? ");
+            if (_input.GetYesNo("Do you need instructions", Input.YesNoMode.FalseOnN))
-            var response = Console.ReadLine();
-            _output.WriteLine();
-
-            if (!response.Equals("N", InvariantCultureIgnoreCase))
             {
                 _output.Write(Strings.Instructions);
 
@@ -47,8 +46,61 @@ namespace SuperStarTrek
 
         public void Play()
         {
-            var quadrant = Initialise();
+            Initialise();
             var gameOver = false;
+            var newQuadrantText = Strings.StartText;
+
+            while (!gameOver)
+            {
+                _enterprise.Quadrant.Display(Strings.NowEntering);
+
+                var command = _input.GetCommand();
+
+                var result = _enterprise.Execute(command);
+
+                gameOver = result.IsGameOver || CheckIfStranded();
+                _currentStardate += result.TimeElapsed;
+                gameOver |= _currentStardate > _finalStarDate;
+            }
+
+            if (_galaxy.KlingonCount > 0)
+            {
+                _output.Write(Strings.EndOfMission, _currentStardate, _galaxy.KlingonCount);
+            }
+            else
+            {
+                _output.Write(Strings.Congratulations, GetEfficiency());
+            }
+        }
+
+        private void Initialise()
+        {
+            _currentStardate = _initialStardate = _random.GetInt(20, 40) * 100;
+            _finalStarDate = _initialStardate + _random.GetInt(25, 35);
+
+            _currentQuadrant = _random.GetCoordinate();
+
+            _galaxy = new Galaxy(_random);
+            _initialKlingonCount = _galaxy.KlingonCount;
+
+            _enterprise = new Enterprise(3000, _random.GetCoordinate(), _output, _random, _input);
+            _enterprise
+                .Add(new WarpEngines(_enterprise, _output, _input))
+                .Add(new ShortRangeSensors(_enterprise, _galaxy, this, _output))
+                .Add(new LongRangeSensors(_galaxy, _output))
+                .Add(new PhaserControl(_enterprise, _output, _input, _random))
+                .Add(new PhotonTubes(10, _enterprise, _output, _input))
+                .Add(new ShieldControl(_enterprise, _output, _input))
+                .Add(new DamageControl(_enterprise, _output))
+                .Add(new LibraryComputer(
+                    _output,
+                    _input,
+                    new CumulativeGalacticRecord(_output, _galaxy),
+                    new StatusReport(this, _galaxy, _enterprise, _output),
+                    new TorpedoDataCalculator(_enterprise, _output),
+                    new StarbaseDataCalculator(_enterprise, _output),
+                    new DirectionDistanceCalculator(_enterprise, _output, _input),
+                    new GalaxyRegionMap(_output, _galaxy)));
 
             _output.Write(Strings.Enterprise);
             _output.Write(
@@ -62,36 +114,21 @@ namespace SuperStarTrek
 
             _input.WaitForAnyKeyButEnter("when ready to accept command");
 
-            _enterprise.Enter(quadrant, Strings.StartText);
+            _enterprise.StartIn(BuildCurrentQuadrant());
-
-            while (!gameOver)
-            {
-                var command = _input.GetCommand();
-
-                gameOver = command == Command.XXX || _enterprise.Execute(command);
-            }
         }
 
-        private Quadrant Initialise()
+        private Quadrant BuildCurrentQuadrant() =>
-        {
+           new Quadrant(_galaxy[_currentQuadrant], _enterprise, _random, _galaxy, _input, _output);
-            var random = new Random();
-
-            _currentStardate = _initialStardate = random.GetInt(20, 40) * 100;
-            _finalStarDate = _initialStardate + random.GetInt(25, 35);
-
-            _currentQuadrant = random.GetCoordinate();
-            _currentSector = random.GetCoordinate();
-
-            _galaxy = new Galaxy();
-            _initialKlingonCount = _galaxy.KlingonCount;
-
-            _enterprise = new Enterprise(3000, random.GetCoordinate());
-            _enterprise.Add(new ShortRangeSensors(_enterprise, _galaxy, this, _output))
-                .Add(new ShieldControl(_enterprise, _output, _input));
-
-            return new Quadrant(_galaxy[_currentQuadrant], _enterprise);
-        }
 
         public bool Replay() => _galaxy.StarbaseCount > 0 && _input.GetString(Strings.ReplayPrompt, "Aye");
+
+        private bool CheckIfStranded()
+        {
+            if (_enterprise.IsStranded) { _output.Write(Strings.Stranded); }
+            return _enterprise.IsStranded;
+        }
+
+        private float GetEfficiency() =>
+            1000 * (float)Math.Pow(_initialKlingonCount / (_currentStardate - _initialStardate), 2);
     }
 }

84 Super Star Trek/csharp/Input.cs

@@ -1,5 +1,7 @@
 using System;
 using System.Linq;
+using SuperStarTrek.Commands;
+using SuperStarTrek.Space;
 using static System.StringComparison;
 
 namespace SuperStarTrek
@@ -25,14 +27,14 @@ namespace SuperStarTrek
             return Console.ReadLine();
         }
 
-        public double GetNumber(string prompt)
+        public float GetNumber(string prompt)
         {
             _output.Prompt(prompt);
 
             while (true)
             {
                 var response = Console.ReadLine();
-                if (double.TryParse(response, out var value))
+                if (float.TryParse(response, out var value))
                 {
                     return value;
                 }
@@ -42,7 +44,14 @@ namespace SuperStarTrek
             }
         }
 
-        public bool TryGetNumber(string prompt, double minValue, double maxValue, out double value)
+        public (float X, float Y) GetCoordinates(string prompt)
+        {
+            _output.Prompt($"{prompt} (X,Y)");
+            var responses = ReadNumbers(2);
+            return (responses[0], responses[1]);
+        }
+
+        public bool TryGetNumber(string prompt, float minValue, float maxValue, out float value)
         {
             value = GetNumber($"{prompt} ({minValue}-{maxValue})");
 
@@ -58,7 +67,7 @@ namespace SuperStarTrek
             {
                 var response = GetString("Command");
 
-                if (response != "" &&
+                if (response.Length >= 3 &&
                     Enum.TryParse(response.Substring(0, 3), ignoreCase: true, out Command parsedCommand))
                 {
                     return parsedCommand;
@@ -72,5 +81,79 @@ namespace SuperStarTrek
                 _output.WriteLine();
             }
         }
+
+        public bool TryGetCourse(string prompt, string officer, out Course course)
+        {
+            if (!TryGetNumber(prompt, 1, 9, out var direction))
+            {
+                _output.WriteLine($"{officer} reports, 'Incorrect course data, sir!'");
+                course = default;
+                return false;
+            }
+
+            course = new Course(direction);
+            return true;
+        }
+
+        public bool GetYesNo(string prompt, YesNoMode mode)
+        {
+            _output.Prompt($"{prompt} (Y/N)");
+            var response = Console.ReadLine().ToUpperInvariant();
+
+            return (mode, response) switch
+            {
+                (YesNoMode.FalseOnN, "N") => false,
+                (YesNoMode.FalseOnN, _) => true,
+                (YesNoMode.TrueOnY, "Y") => true,
+                (YesNoMode.TrueOnY, _) => false,
+                _ => throw new ArgumentOutOfRangeException(nameof(mode), mode, "Invalid value")
+            };
+        }
+
+        private float[] ReadNumbers(int quantity)
+        {
+            var numbers = new float[quantity];
+            var index = 0;
+            bool tryAgain;
+
+            do
+            {
+                tryAgain = false;
+                var responses = Console.ReadLine().Split(',');
+                if (responses.Length > quantity)
+                {
+                    _output.WriteLine("!Extra input ingored");
+                }
+
+                for (; index < responses.Length; index++)
+                {
+                    if (!float.TryParse(responses[index], out numbers[index]))
+                    {
+                        _output.WriteLine("!Number expected - retry input line");
+                        _output.Prompt();
+                        tryAgain = true;
+                        break;
+                    }
+                }
+            } while (tryAgain);
+
+            if (index < quantity)
+            {
+                _output.Prompt("?");
+                var responses = ReadNumbers(quantity - index);
+                for (int i = 0; i < responses.Length; i++, index++)
+                {
+                    numbers[index] = responses[i];
+                }
+            }
+
+            return numbers;
+        }
+
+        public enum YesNoMode
+        {
+            TrueOnY,
+            FalseOnN
+        }
     }
 }

84 Super Star Trek/csharp/Objects/Enterprise.cs

@@ -1,6 +1,8 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using System.Text;
+using SuperStarTrek.Commands;
 using SuperStarTrek.Resources;
 using SuperStarTrek.Space;
 using SuperStarTrek.Systems;
@@ -10,84 +12,71 @@ namespace SuperStarTrek.Objects
     internal class Enterprise
     {
         private readonly int _maxEnergy;
+        private readonly Output _output;
         private readonly List<Subsystem> _systems;
         private readonly Dictionary<Command, Subsystem> _commandExecutors;
+        private readonly Random _random;
+        private readonly Input _input;
         private Quadrant _quadrant;
-        private ShieldControl _shieldControl;
 
-        public Enterprise(int maxEnergy, Coordinates sector)
+        public Enterprise(int maxEnergy, Coordinates sector, Output output, Random random, Input input)
         {
-            Sector = sector;
+            SectorCoordinates = sector;
             TotalEnergy = _maxEnergy = maxEnergy;
 
             _systems = new List<Subsystem>();
             _commandExecutors = new Dictionary<Command, Subsystem>();
+            _output = output;
+            _random = random;
+            _input = input;
         }
 
-        public Coordinates Quadrant => _quadrant.Coordinates;
+        public Quadrant Quadrant => _quadrant;
-        public Coordinates Sector { get; }
+        public Coordinates QuadrantCoordinates => _quadrant.Coordinates;
-        public string Condition => GetCondition();
+        public Coordinates SectorCoordinates { get; private set; }
-        public double Shields => _shieldControl.Energy;
-        public double Energy => TotalEnergy - Shields;
-        public double TotalEnergy { get; private set; }
-        public int TorpedoCount { get; }
 
-        public bool IsDocked { get; private set; }
+        public string Condition => GetCondition();
+        public LibraryComputer Computer => (LibraryComputer)_commandExecutors[Command.COM];
+        public ShieldControl ShieldControl => (ShieldControl)_commandExecutors[Command.SHE];
+        public float Energy => TotalEnergy - ShieldControl.ShieldEnergy;
+        public float TotalEnergy { get; private set; }
+        public int DamagedSystemCount => _systems.Count(s => s.IsDamaged);
+        public IEnumerable<Subsystem> Systems => _systems;
+        public PhotonTubes PhotonTubes => (PhotonTubes)_commandExecutors[Command.TOR];
+        public bool IsDocked => _quadrant.EnterpriseIsNextToStarbase;
+        public bool IsStranded => TotalEnergy < 10 || Energy < 10 && ShieldControl.IsDamaged;
 
         public Enterprise Add(Subsystem system)
         {
             _systems.Add(system);
             _commandExecutors[system.Command] = system;
 
-            if (system is ShieldControl shieldControl) { _shieldControl = shieldControl; }
-
             return this;
         }
 
-        public string GetDamageReport()
+        public void StartIn(Quadrant quadrant)
-        {
-            var report = new StringBuilder();
-            report.AppendLine().AppendLine().AppendLine("Device             State of Repair");
-            foreach (var system in _systems)
-            {
-                report.Append(system.Name.PadRight(25)).AppendLine(system.Condition.ToString(" 0.00;-0.00"));
-            }
-            report.AppendLine();
-            return report.ToString();
-        }
-
-        public void Enter(Quadrant quadrant, string entryTextFormat)
         {
             _quadrant = quadrant;
-
+            quadrant.Display(Strings.StartText);
-            var _output = new Output();
-            _output.Write(entryTextFormat, quadrant);
-
-            if (quadrant.HasKlingons)
-            {
-                _output.Write(Strings.CombatArea);
-                if (Shields <= 200) { _output.Write(Strings.LowShields); }
-            }
-
-            IsDocked = quadrant.EnterpriseIsNextToStarbase;
-
-            Execute(Command.SRS);
         }
 
         private string GetCondition() =>
             (_quadrant.HasKlingons, Energy / _maxEnergy) switch
             {
                 (true, _) => "*Red*",
-                (_, < 0.1) => "Yellow",
+                (_, < 0.1f) => "Yellow",
                 _ => "Green"
             };
 
-        public bool Execute(Command command)
+        public CommandResult Execute(Command command)
         {
-            _commandExecutors[command].ExecuteCommand(_quadrant);
+            if (command == Command.XXX) { return CommandResult.GameOver; }
-            return false;
+
+            return _commandExecutors[command].ExecuteCommand(_quadrant);
         }
 
+        public void Refuel() => TotalEnergy = _maxEnergy;
+
         internal bool Recognises(string command)
         {
             throw new NotImplementedException();
@@ -99,5 +88,143 @@ namespace SuperStarTrek.Objects
         }
 
         public override string ToString() => "<*>";
+
+        internal void UseEnergy(float amountUsed)
+        {
+            TotalEnergy -= amountUsed;
+        }
+
+        internal CommandResult TakeHit(Coordinates sector, int hitStrength)
+        {
+            _output.WriteLine($"{hitStrength} unit hit on Enterprise from sector {sector}");
+            ShieldControl.AbsorbHit(hitStrength);
+
+            if (ShieldControl.ShieldEnergy <= 0)
+            {
+                _output.WriteLine(Strings.Destroyed);
+                return CommandResult.GameOver;
+            }
+
+            _output.WriteLine($"      <Shields down to {ShieldControl.ShieldEnergy} units>");
+
+            if (hitStrength >= 20)
+            {
+                TakeDamage(hitStrength);
+            }
+
+            return CommandResult.Ok;
+        }
+
+        private void TakeDamage(float hitStrength)
+        {
+            var hitShieldRatio = hitStrength / ShieldControl.ShieldEnergy;
+            if (_random.GetFloat() > 0.6 || hitShieldRatio <= 0.02f)
+            {
+                return;
+            }
+
+            var system = _systems[_random.Get1To8Inclusive() - 1];
+            system.TakeDamage(hitShieldRatio + 0.5f * _random.GetFloat());
+            _output.WriteLine($"Damage Control reports, '{system.Name} damaged by the hit.'");
+        }
+
+        internal void RepairSystems(float repairWorkDone)
+        {
+            var repairedSystems = new List<string>();
+
+            foreach (var system in _systems.Where(s => s.IsDamaged))
+            {
+                if (system.Repair(repairWorkDone))
+                {
+                    repairedSystems.Add(system.Name);
+                }
+            }
+
+            if (repairedSystems.Any())
+            {
+                _output.WriteLine("Damage Control report:");
+                foreach (var systemName in repairedSystems)
+                {
+                    _output.WriteLine($"        {systemName} repair completed.");
+                }
+            }
+        }
+
+        internal void VaryConditionOfRandomSystem()
+        {
+            if (_random.GetFloat() > 0.2f) { return; }
+
+            var system = _systems[_random.Get1To8Inclusive() - 1];
+            _output.Write($"Damage Control report:  {system.Name} ");
+            if (_random.GetFloat() >= 0.6)
+            {
+                system.Repair(_random.GetFloat() * 3 + 1);
+                _output.WriteLine("state of repair improved");
+            }
+            else
+            {
+                system.TakeDamage(_random.GetFloat() * 5 + 1);
+                _output.WriteLine("damaged");
+            }
+        }
+
+        internal float Move(Course course, float warpFactor, int distance)
+        {
+            var (quadrant, sector) = MoveWithinQuadrant(course, distance) ?? MoveBeyondQuadrant(course, distance);
+
+            if (quadrant != _quadrant.Coordinates)
+            {
+                _quadrant = new Quadrant(_quadrant.Galaxy[quadrant], this, _random, _quadrant.Galaxy, _input, _output);
+            }
+            _quadrant.SetEnterpriseSector(sector);
+            SectorCoordinates = sector;
+
+            TotalEnergy -= distance + 10;
+            if (Energy < 0)
+            {
+                _output.WriteLine("Shield Control supplies energy to complete the maneuver.");
+                ShieldControl.ShieldEnergy = Math.Max(0, TotalEnergy);
+            }
+
+            return GetTimeElapsed(quadrant, warpFactor);
+        }
+
+        private (Coordinates, Coordinates)? MoveWithinQuadrant(Course course, int distance)
+        {
+            var currentSector = SectorCoordinates;
+            foreach (var (sector, index) in course.GetSectorsFrom(SectorCoordinates).Select((s, i) => (s, i)))
+            {
+                if (distance == 0) { break; }
+
+                if (_quadrant.HasObjectAt(sector))
+                {
+                    _output.WriteLine($"Warp engines shut down at sector {currentSector} dues to bad navigation");
+                    distance = 0;
+                    break;
+                }
+
+                currentSector = sector;
+                distance -= 1;
+            }
+
+            return distance == 0 ? (_quadrant.Coordinates, currentSector) : null;
+        }
+
+        private (Coordinates, Coordinates) MoveBeyondQuadrant(Course course, int distance)
+        {
+            var (complete, quadrant, sector) = course.GetDestination(QuadrantCoordinates, SectorCoordinates, distance);
+
+            if (!complete)
+            {
+                _output.Write(Strings.PermissionDenied, sector, quadrant);
+            }
+
+            return (quadrant, sector);
+        }
+
+        private float GetTimeElapsed(Coordinates finalQuadrant, float warpFactor) =>
+            finalQuadrant == _quadrant.Coordinates
+                ? Math.Min(1, (float)Math.Round(warpFactor, 1, MidpointRounding.ToZero))
+                : 1;
     }
 }

84 Super Star Trek/csharp/Objects/Klingon.cs

@@ -1,14 +1,42 @@
+using SuperStarTrek.Commands;
+using SuperStarTrek.Space;
+
 namespace SuperStarTrek.Objects
 {
     internal class Klingon
     {
-        private double _energy;
+        private readonly Random _random;
 
-        public Klingon()
+        public Klingon(Coordinates sector, Random random)
         {
-            _energy = new Random().GetDouble(100, 300);
+            Sector = sector;
+            _random = random;
+            Energy = _random.GetFloat(100, 300);
         }
 
+        public float Energy { get; private set; }
+        public Coordinates Sector { get; private set; }
+
         public override string ToString() => "+K+";
+
+        public CommandResult FireOn(Enterprise enterprise)
+        {
+            var attackStrength = _random.GetFloat();
+            var distanceToEnterprise = Sector.GetDistanceTo(enterprise.SectorCoordinates);
+            var hitStrength = (int)(Energy * (2 + attackStrength) / distanceToEnterprise);
+            Energy /= 3 + attackStrength;
+
+            return enterprise.TakeHit(Sector, hitStrength);
+        }
+
+        internal bool TakeHit(int hitStrength)
+        {
+            if (hitStrength < 0.15 * Energy) { return false; }
+
+            Energy -= hitStrength;
+            return true;
+        }
+
+        internal void MoveTo(Coordinates newSector) => Sector = newSector;
     }
 }

84 Super Star Trek/csharp/Objects/Starbase.cs

@@ -1,7 +1,44 @@
+using SuperStarTrek.Resources;
+using SuperStarTrek.Space;
+
 namespace SuperStarTrek.Objects
 {
     internal class Starbase
     {
+        private readonly Input _input;
+        private readonly Output _output;
+        private readonly float _repairDelay;
+
+        public Starbase(Coordinates sector, Random random, Input input, Output output)
+        {
+            Sector = sector;
+            _repairDelay = random.GetFloat() * 0.5f;
+            _input = input;
+            _output = output;
+        }
+
+        internal Coordinates Sector { get; }
         public override string ToString() => ">!<";
+
+        internal bool TryRepair(Enterprise enterprise, out float repairTime)
+        {
+            repairTime = enterprise.DamagedSystemCount * 0.1f + _repairDelay;
+            if (repairTime >= 1) { repairTime = 0.9f; }
+
+            _output.Write(Strings.RepairEstimate, repairTime);
+            if (_input.GetYesNo(Strings.RepairPrompt, Input.YesNoMode.TrueOnY))
+            {
+                foreach (var system in enterprise.Systems)
+                {
+                    system.Repair();
+                }
+                return true;
+            }
+
+            repairTime = 0;
+            return false;
+        }
+
+        internal void ProtectEnterprise() => _output.WriteLine(Strings.Protected);
     }
 }

84 Super Star Trek/csharp/Output.cs

@@ -4,12 +4,37 @@ namespace SuperStarTrek
 {
     internal class Output
     {
-        public void Write(string text) => Console.Write(text);
+        public Output Write(string text)
-        public void Write(string format, params object[] args) => Console.Write(format, args);
+        {
-        public void WriteLine(string text = "") => Console.WriteLine(text);
+            Console.Write(text);
+            return this;
+        }
 
-        public void NextLine() => Console.WriteLine();
+        public Output Write(string format, params object[] args)
+        {
+            Console.Write(format, args);
+            return this;
+        }
+
+        public Output WriteLine(string text = "")
+        {
+            Console.WriteLine(text);
+            return this;
+        }
+
+
+        public Output NextLine()
+        {
+            Console.WriteLine();
+            return this;
+        }
+
+
+        public Output Prompt(string text = "")
+        {
+            Console.Write($"{text}? ");
+            return this;
+        }
 
-        public void Prompt(string text = "") => Console.Write($"{text}? ");
     }
 }

84 Super Star Trek/csharp/Program.cs

@@ -29,6 +29,7 @@ namespace SuperStarTrek
     {
         static void Main()
         {
+            var foo = Utils.DirectionAndDistance.From(1,1).To(4,5);
             var game = new Game();
 
             game.DoIntroduction();

84 Super Star Trek/csharp/Random.cs

@@ -6,20 +6,20 @@ namespace SuperStarTrek
     {
         private static readonly System.Random _random = new();
 
-        public Coordinates GetCoordinate() => new Coordinates(Get1To8Inclusive(), Get1To8Inclusive());
+        public Coordinates GetCoordinate() => new Coordinates(Get1To8Inclusive() - 1, Get1To8Inclusive() - 1);
 
         // Duplicates the algorithm used in the original code to get an integer value from 1 to 8, inclusive:
         //     475 DEF FNR(R)=INT(RND(R)*7.98+1.01)
         // Returns a value from 1 to 8, inclusive.
         // Note there's a slight bias away from the extreme values, 1 and 8.
-        public int Get1To8Inclusive() => (int)(_random.NextDouble() * 7.98 + 1.01);
+        public int Get1To8Inclusive() => (int)(GetFloat() * 7.98 + 1.01);
 
         public int GetInt(int inclusiveMinValue, int exclusiveMaxValue) =>
             _random.Next(inclusiveMinValue, exclusiveMaxValue);
 
-        public double GetDouble() => _random.NextDouble();
+        public float GetFloat() => (float)_random.NextDouble();
 
-        public double GetDouble(double inclusiveMinValue, double exclusiveMaxValue)
+        public float GetFloat(float inclusiveMinValue, float exclusiveMaxValue)
-            => _random.NextDouble() * (exclusiveMaxValue - inclusiveMinValue) + inclusiveMinValue;
+            => GetFloat() * (exclusiveMaxValue - inclusiveMinValue) + inclusiveMinValue;
     }
 }

84 Super Star Trek/csharp/Resources/ComputerFunctions.txt

@@ -0,0 +1,9 @@
+
+Functions available from Library-Computer:
+   0 = Cumulative galactic record
+   1 = Status report
+   2 = Photon torpedo data
+   3 = Starbase nav data
+   4 = Direction/distance calculator
+   5 = Galaxy 'region name' map
+

84 Super Star Trek/csharp/Resources/Congratulations.txt

@@ -0,0 +1,4 @@
+Congratulations, Captain!  The last Klingon battle cruiser
+menacing the Federation has been destroyed.
+
+Your efficiency rating is {0}.

84 Super Star Trek/csharp/Resources/CourtMartial.txt

@@ -0,0 +1,3 @@
+
+Starfleet Command reviewing your record to consider
+court martial!

84 Super Star Trek/csharp/Resources/Destroyed.txt

@@ -0,0 +1 @@
+The Enterprise has been destroyed.  The Federation will be conquered.

84 Super Star Trek/csharp/Resources/EndOfMission.txt

@@ -0,0 +1,3 @@
+Is is stardate {0}.
+There were {1} Klingon battle cruisers left at
+the end of your mission.

84 Super Star Trek/csharp/Resources/Instructions.txt

@@ -1,3 +1,4 @@
+
       INSTRUCTIONS FOR 'SUPER STAR TREK'
 
 1. When you see "Command ?" printed, enter one of the legal

84 Super Star Trek/csharp/Resources/NoEnemyShips.txt

@@ -0,0 +1,2 @@
+Science Officer Spock reports, 'Sensors show no enemy ships
+                                in this quadrant'

84 Super Star Trek/csharp/Resources/NoStarbase.txt

@@ -0,0 +1 @@
+Mr. Spock reports, 'Sensors show no starbases in this quadrant.'

84 Super Star Trek/csharp/Resources/NowEntering.txt

@@ -0,0 +1,2 @@
+Now entering {0} quadrant . . .
+

84 Super Star Trek/csharp/Resources/PermissionDenied.txt

@@ -0,0 +1,5 @@
+Lt. Uhura report message from Starfleet Command:
+  'Permission to attempt crossing of galactic perimeter
+  is hereby *Denied*. Shut down your engines.'
+Chief Engineer Scott reports, 'Warp engines shut down
+  at sector {0} of quadrant {1}.'

84 Super Star Trek/csharp/Resources/Protected.txt

@@ -0,0 +1 @@
+Starbase shields protect the Enterprise

84 Super Star Trek/csharp/Resources/RegionNames.txt

@@ -0,0 +1,8 @@
+      Antares                  Sirius
+       Rigel                   Deneb
+      Procyon                 Capella
+        Vega                 Betelgeuse
+      Canopus                Aldebaran
+       Altair                 Regulus
+    Sagittarius               Arcturus
+       Pollux                  Spica

84 Super Star Trek/csharp/Resources/RelievedOfCommand.txt

@@ -0,0 +1,3 @@
+
+That does it, Captain!!  You are hereby relieved of command
+and sentenced to 99 stardates at hard labor on Cygnus 12!!

84 Super Star Trek/csharp/Resources/RepairEstimate.txt

@@ -0,0 +1,2 @@
+Technicians standing by to effect repairs to your ship;
+Estimated time to repair: {0} stardates.

84 Super Star Trek/csharp/Resources/RepairPrompt.txt

@@ -0,0 +1 @@
+Will you authorize the repair order (Y/N)

84 Super Star Trek/csharp/Resources/ReplayPrompt.txt

@@ -1,3 +1,5 @@
+
+
 The Federation is in need of a new starship commander
 for a similar mission -- if there is a volunteer
 let him step forward and enter 'Aye'

84 Super Star Trek/csharp/Resources/Stranded.txt

@@ -0,0 +1,3 @@
+** FATAL ERROR **   You've just stranded your ship in space
+You have insufficient maneuvering energy, and shield control
+is presently incapable of cross-circuiting to engine room!!

84 Super Star Trek/csharp/Resources/Strings.cs

@@ -7,14 +7,29 @@ namespace SuperStarTrek.Resources
     internal static class Strings
     {
         public static string CombatArea => GetResource();
+        public static string ComputerFunctions => GetResource();
+        public static string Congratulations => GetResource();
+        public static string CourtMartial => GetResource();
+        public static string Destroyed => GetResource();
+        public static string EndOfMission => GetResource();
         public static string Enterprise => GetResource();
         public static string Instructions => GetResource();
         public static string LowShields => GetResource();
+        public static string NoEnemyShips => GetResource();
+        public static string NoStarbase => GetResource();
+        public static string NowEntering => GetResource();
         public static string Orders => GetResource();
+        public static string PermissionDenied => GetResource();
+        public static string Protected => GetResource();
+        public static string RegionNames => GetResource();
+        public static string RelievedOfCommand => GetResource();
+        public static string RepairEstimate => GetResource();
+        public static string RepairPrompt => GetResource();
         public static string ReplayPrompt => GetResource();
         public static string ShieldsDropped => GetResource();
         public static string ShortRangeSensorsOut => GetResource();
         public static string StartText => GetResource();
+        public static string Stranded => GetResource();
         public static string Title => GetResource();
 
         private static string GetResource([CallerMemberName] string name = "")

84 Super Star Trek/csharp/Space/Coordinate.cs

@@ -1,27 +0,0 @@
-using System;
-
-namespace SuperStarTrek.Space
-{
-    // Represents the corrdintate of a quadrant in the galaxy, or a sector in a quadrant.
-    // Note that the origin is top-left, x increase downwards, and y increases to the right.
-    internal record Coordinates
-    {
-        public Coordinates(int x, int y)
-        {
-            X = Validated(x, nameof(x));
-            Y = Validated(y, nameof(y));
-        }
-
-        public int X { get; }
-        public int Y { get; }
-
-        private int Validated(int value, string argumentName)
-        {
-            if (value >= 1 && value <= 8) { return value; }
-
-            throw new ArgumentOutOfRangeException(argumentName, value, "Must be 1 to 8 inclusive");
-        }
-
-        public override string ToString() => $"{X} , {Y}";
-    }
-}

84 Super Star Trek/csharp/Space/Coordinates.cs

@@ -0,0 +1,67 @@
+using System;
+using SuperStarTrek.Utils;
+
+namespace SuperStarTrek.Space
+{
+    // Represents the corrdintate of a quadrant in the galaxy, or a sector in a quadrant.
+    // Note that the origin is top-left, x increase downwards, and y increases to the right.
+    internal record Coordinates
+    {
+        public Coordinates(int x, int y)
+        {
+            X = Validated(x, nameof(x));
+            Y = Validated(y, nameof(y));
+
+            RegionIndex = (X << 1) + (Y >> 2);
+            SubRegionIndex = Y % 4;
+        }
+
+        public int X { get; }
+        public int Y { get; }
+        public int RegionIndex { get; }
+        public int SubRegionIndex { get; }
+
+        private int Validated(int value, string argumentName)
+        {
+            if (value >= 0 && value <= 7) { return value; }
+
+            throw new ArgumentOutOfRangeException(argumentName, value, "Must be 0 to 7 inclusive");
+        }
+
+        private static bool IsValid(int value) => value >= 0 && value <= 7;
+
+        public override string ToString() => $"{X+1} , {Y+1}";
+
+        internal void Deconstruct(out int x, out int y)
+        {
+            x = X;
+            y = Y;
+        }
+
+        internal static bool TryCreate(float x, float y, out Coordinates coordinates)
+        {
+            var roundedX = Round(x);
+            var roundedY = Round(y);
+
+            if (IsValid(roundedX) && IsValid(roundedY))
+            {
+                coordinates = new Coordinates(roundedX, roundedY);
+                return true;
+            }
+
+            coordinates = default;
+            return false;
+
+            static int Round(float value) => (int)Math.Round(value, MidpointRounding.AwayFromZero);
+        }
+
+        internal (float Direction, float Distance) GetDirectionAndDistanceTo(Coordinates destination) =>
+            DirectionAndDistance.From(this).To(destination);
+
+        internal float GetDistanceTo(Coordinates destination)
+        {
+            var (_, distance) = GetDirectionAndDistanceTo(destination);
+            return distance;
+        }
+    }
+}

84 Super Star Trek/csharp/Space/Course.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 
 namespace SuperStarTrek.Space
 {
@@ -24,7 +25,7 @@ namespace SuperStarTrek.Space
             (0, 1)
         };
 
-        public Course(double direction)
+        internal Course(float direction)
         {
             if (direction < 1 || direction > 9)
             {
@@ -44,7 +45,53 @@ namespace SuperStarTrek.Space
             DeltaY = baseCardinal.DeltaY + (nextCardinal.DeltaY - baseCardinal.DeltaY) * fractionalDirection;
         }
 
-        public double DeltaX { get; }
+        internal float DeltaX { get; }
-        public double DeltaY { get; }
+        internal float DeltaY { get; }
+
+        internal IEnumerable<Coordinates> GetSectorsFrom(Coordinates start)
+        {
+            (float x, float y) = start;
+
+            while(true)
+            {
+                x += DeltaX;
+                y += DeltaY;
+
+                if (!Coordinates.TryCreate(x, y, out var coordinates))
+                {
+                    yield break;
+                }
+
+                yield return coordinates;
+            }
+        }
+
+        internal (bool, Coordinates, Coordinates) GetDestination(Coordinates quadrant, Coordinates sector, int distance)
+        {
+            var (xComplete, quadrantX, sectorX) = GetNewCoordinate(quadrant.X, sector.X, DeltaX * distance);
+            var (yComplete, quadrantY, sectorY) = GetNewCoordinate(quadrant.Y, sector.Y, DeltaY * distance);
+
+            return (xComplete && yComplete, new Coordinates(quadrantX, quadrantY), new Coordinates(sectorX, sectorY));
+        }
+
+        private (bool, int, int) GetNewCoordinate(int quadrant, int sector, float sectorsTravelled)
+        {
+            var galacticCoordinate = quadrant * 8 + sector + sectorsTravelled;
+            var newQuadrant = (int)(galacticCoordinate / 8);
+            var newSector = (int)(galacticCoordinate - newQuadrant * 8);
+
+            if (newSector == -1)
+            {
+                newQuadrant -= 1;
+                newSector = 7;
+            }
+
+            return newQuadrant switch
+            {
+                < 0 => (false, 0, 0),
+                > 7 => (false, 7, 7),
+                _ => (true, newQuadrant, newSector)
+            };
+        }
     }
 }

84 Super Star Trek/csharp/Space/Galaxy.cs

@@ -1,17 +1,37 @@
+using System.Collections;
+using System.Collections.Generic;
 using System.Linq;
+using SuperStarTrek.Objects;
+using SuperStarTrek.Resources;
+
+using static System.StringSplitOptions;
 
 namespace SuperStarTrek.Space
 {
     internal class Galaxy
     {
+        private static readonly string[] _regionNames;
+        private static readonly string[] _subRegionIdentifiers;
         private readonly QuadrantInfo[][] _quadrants;
+        private readonly Random _random;
 
-        public Galaxy()
+        static Galaxy()
         {
-            var random = new Random();
+            _regionNames = Strings.RegionNames.Split(new[] { ' ', '\n' }, RemoveEmptyEntries | TrimEntries);
+            _subRegionIdentifiers = new[] { "I", "II", "III", "IV" };
+        }
 
-            _quadrants = Enumerable.Range(1, 8).Select(x =>
+        public Galaxy(Random random)
-                Enumerable.Range(1, 8).Select(y => QuadrantInfo.Create(new Coordinates(x, y), "")).ToArray())
+        {
+            _random = random;
+
+            _quadrants = Enumerable
+                .Range(0, 8)
+                .Select(x => Enumerable
+                    .Range(0, 8)
+                    .Select(y => new Coordinates(x, y))
+                    .Select(c => QuadrantInfo.Create(c, GetQuadrantName(c)))
+                    .ToArray())
                 .ToArray();
 
             if (StarbaseCount == 0)
@@ -26,9 +46,22 @@ namespace SuperStarTrek.Space
             }
         }
 
-        public QuadrantInfo this[Coordinates coordinate] => _quadrants[coordinate.X - 1][coordinate.Y - 1];
+        public QuadrantInfo this[Coordinates coordinate] => _quadrants[coordinate.X][coordinate.Y];
 
         public int KlingonCount => _quadrants.SelectMany(q => q).Sum(q => q.KlingonCount);
         public int StarbaseCount => _quadrants.SelectMany(q => q).Count(q => q.HasStarbase);
+        public IEnumerable<IEnumerable<QuadrantInfo>> Quadrants => _quadrants;
+
+        private static string GetQuadrantName(Coordinates coordinates) =>
+            $"{_regionNames[coordinates.RegionIndex]} {_subRegionIdentifiers[coordinates.SubRegionIndex]}";
+
+        public IEnumerable<IEnumerable<QuadrantInfo>> GetNeighborhood(Quadrant quadrant) =>
+            Enumerable.Range(-1, 3)
+                .Select(dx => dx + quadrant.Coordinates.X)
+                .Select(x => GetNeighborhoodRow(quadrant, x));
+        private IEnumerable<QuadrantInfo> GetNeighborhoodRow(Quadrant quadrant, int x) =>
+            Enumerable.Range(-1, 3)
+                .Select(dy => dy + quadrant.Coordinates.Y)
+                .Select(y => y < 0 || y > 7 || x < 0 || x > 7 ? null : _quadrants[x][y]);
     }
 }

84 Super Star Trek/csharp/Space/Quadrant.cs

@@ -1,7 +1,9 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using SuperStarTrek.Commands;
 using SuperStarTrek.Objects;
+using SuperStarTrek.Resources;
 
 namespace SuperStarTrek.Space
 {
@@ -10,42 +12,56 @@ namespace SuperStarTrek.Space
         private readonly QuadrantInfo _info;
         private readonly Random _random;
         private readonly Dictionary<Coordinates, object> _sectors;
-        private readonly Coordinates _enterpriseSector;
+        private readonly Enterprise _enterprise;
-        private readonly Coordinates _starbaseSector;
+        private readonly Output _output;
+        private bool _displayed = false;
 
-        public Quadrant(QuadrantInfo info, Enterprise enterprise)
+        public Quadrant(
+            QuadrantInfo info,
+            Enterprise enterprise,
+            Random random,
+            Galaxy galaxy,
+            Input input,
+            Output output)
         {
             _info = info;
-            _random = new Random();
+            _random = random;
+            _output = output;
+            Galaxy = galaxy;
 
-            _enterpriseSector = enterprise.Sector;
+            info.MarkAsKnown();
-            _sectors = new Dictionary<Coordinates, object> { [enterprise.Sector] = enterprise };
+            _sectors = new() { [enterprise.SectorCoordinates] = _enterprise = enterprise };
-            PositionObject(() => new Klingon(), _info.KlingonCount);
+            PositionObject(sector => new Klingon(sector, _random), _info.KlingonCount);
             if (_info.HasStarbase)
             {
-                _starbaseSector = PositionObject(() => new Starbase());
+                Starbase = PositionObject(sector => new Starbase(sector, _random, input, output));
             }
-            PositionObject(() => new Star(), _info.StarCount);
+            PositionObject(_ => new Star(), _info.StarCount);
         }
 
         public Coordinates Coordinates => _info.Coordinates;
         public bool HasKlingons => _info.KlingonCount > 0;
+        public int KlingonCount => _info.KlingonCount;
         public bool HasStarbase => _info.HasStarbase;
+        public Starbase Starbase { get; }
+        internal Galaxy Galaxy { get; }
         public bool EnterpriseIsNextToStarbase =>
             _info.HasStarbase &&
-            Math.Abs(_enterpriseSector.X - _starbaseSector.X) <= 1 &&
+            Math.Abs(_enterprise.SectorCoordinates.X - Starbase.Sector.X) <= 1 &&
-            Math.Abs(_enterpriseSector.Y - _starbaseSector.Y) <= 1;
+            Math.Abs(_enterprise.SectorCoordinates.Y - Starbase.Sector.Y) <= 1;
+
+        internal IEnumerable<Klingon> Klingons => _sectors.Values.OfType<Klingon>();
 
         public override string ToString() => _info.Name;
 
-        private Coordinates PositionObject(Func<object> objectFactory)
+        private T PositionObject<T>(Func<Coordinates, T> objectFactory)
         {
             var sector = GetRandomEmptySector();
-            _sectors[sector] = objectFactory.Invoke();
+            _sectors[sector] = objectFactory.Invoke(sector);
-            return sector;
+            return (T)_sectors[sector];
         }
 
-        private void PositionObject(Func<object> objectFactory, int count)
+        private void PositionObject(Func<Coordinates, object> objectFactory, int count)
         {
             for (int i = 0; i < count; i++)
             {
@@ -53,6 +69,91 @@ namespace SuperStarTrek.Space
             }
         }
 
+        internal void Display(string textFormat)
+        {
+            if (_displayed) { return; }
+
+            _output.Write(textFormat, this);
+
+            if (_info.KlingonCount > 0)
+            {
+                _output.Write(Strings.CombatArea);
+                if (_enterprise.ShieldControl.ShieldEnergy <= 200) { _output.Write(Strings.LowShields); }
+            }
+
+            _enterprise.Execute(Command.SRS);
+
+            _displayed = true;
+        }
+
+        internal bool HasObjectAt(Coordinates coordinates) => _sectors.ContainsKey(coordinates);
+
+        internal bool TorpedoCollisionAt(Coordinates coordinates, out string message, out bool gameOver)
+        {
+            gameOver = false;
+            message = default;
+
+            switch (_sectors.GetValueOrDefault(coordinates))
+            {
+                case Klingon klingon:
+                    message = Remove(klingon);
+                    gameOver = Galaxy.KlingonCount == 0;
+                    return true;
+
+                case Star _:
+                    message = $"Star at {coordinates} absorbed torpedo energy.";
+                    return true;
+
+                case Starbase _:
+                    _sectors.Remove(coordinates);
+                    _info.RemoveStarbase();
+                    message = "*** Starbase destroyed ***" +
+                        (Galaxy.StarbaseCount > 0 ? Strings.CourtMartial : Strings.RelievedOfCommand);
+                    gameOver = Galaxy.StarbaseCount == 0;
+                    return true;
+
+                default:
+                    return false;
+            }
+        }
+
+        internal string Remove(Klingon klingon)
+        {
+            _sectors.Remove(klingon.Sector);
+            _info.RemoveKlingon();
+            return "*** Klingon destroyed ***";
+        }
+
+        internal CommandResult KlingonsMoveAndFire()
+        {
+            foreach (var klingon in Klingons.ToList())
+            {
+                var newSector = GetRandomEmptySector();
+                _sectors.Remove(klingon.Sector);
+                _sectors[newSector] = klingon;
+                klingon.MoveTo(newSector);
+            }
+
+            return KlingonsFireOnEnterprise();
+        }
+
+        internal CommandResult KlingonsFireOnEnterprise()
+        {
+            if (EnterpriseIsNextToStarbase && Klingons.Any())
+            {
+                Starbase.ProtectEnterprise();
+                return CommandResult.Ok;
+            }
+
+            foreach (var klingon in Klingons)
+            {
+                var result = klingon.FireOn(_enterprise);
+                if (result.IsGameOver) { return result; }
+            }
+
+            return CommandResult.Ok;
+        }
+
         private Coordinates GetRandomEmptySector()
         {
             while (true)
@@ -65,15 +166,21 @@ namespace SuperStarTrek.Space
             }
         }
 
-        public IEnumerable<string> GetDisplayLines() => Enumerable.Range(1, 8).Select(x => GetDisplayLine(x));
+        public IEnumerable<string> GetDisplayLines() => Enumerable.Range(0, 8).Select(x => GetDisplayLine(x));
 
         private string GetDisplayLine(int x)
             => string.Join(
                 " ",
                 Enumerable
-                    .Range(1, 8)
+                    .Range(0, 8)
                     .Select(y => new Coordinates(x, y))
                     .Select(c => _sectors.GetValueOrDefault(c))
                     .Select(o => o?.ToString() ?? "   "));
+
+        internal void SetEnterpriseSector(Coordinates sector)
+        {
+            _sectors.Remove(_enterprise.SectorCoordinates);
+            _sectors[sector] = _enterprise;
+        }
     }
 }

84 Super Star Trek/csharp/Space/QuadrantInfo.cs

@@ -1,7 +1,11 @@
+using SuperStarTrek.Objects;
+
 namespace SuperStarTrek.Space
 {
     internal class QuadrantInfo
     {
+        private bool _isKnown;
+
         private QuadrantInfo(Coordinates coordinates, string name, int klingonCount, int starCount, bool hasStarbase)
         {
             Coordinates = coordinates;
@@ -20,14 +24,14 @@ namespace SuperStarTrek.Space
         public static QuadrantInfo Create(Coordinates coordinates, string name)
         {
             var random = new Random();
-            var klingonCount = random.GetDouble() switch
+            var klingonCount = random.GetFloat() switch
             {
-                > 0.98 => 3,
+                > 0.98f => 3,
-                > 0.95 => 2,
+                > 0.95f => 2,
-                > 0.80 => 1,
+                > 0.80f => 1,
                 _ => 0
             };
-            var hasStarbase = random.GetDouble() > 0.96;
+            var hasStarbase = random.GetFloat() > 0.96f;
             var starCount = random.Get1To8Inclusive();
 
             return new QuadrantInfo(coordinates, name, klingonCount, starCount, hasStarbase);
@@ -36,5 +40,25 @@ namespace SuperStarTrek.Space
         internal void AddKlingon() => KlingonCount += 1;
 
         internal void AddStarbase() => HasStarbase = true;
+
+        internal void MarkAsKnown() => _isKnown = true;
+
+        internal string Scan()
+        {
+            _isKnown = true;
+            return ToString();
+        }
+
+        public override string ToString() => _isKnown ? $"{KlingonCount}{(HasStarbase ? 1 : 0)}{StarCount}" : "***";
+
+        internal void RemoveKlingon()
+        {
+            if (KlingonCount > 0)
+            {
+                KlingonCount -= 1;
+            }
+        }
+
+        internal void RemoveStarbase() => HasStarbase = false;
     }
 }

84 Super Star Trek/csharp/StringExtensions.cs

@@ -0,0 +1,7 @@
+namespace SuperStarTrek
+{
+    internal static class StringExtensions
+    {
+        internal static string Pluralize(this string singular, int quantity) => singular + (quantity > 1 ? "s" : "");
+    }
+}

84 Super Star Trek/csharp/Systems/ComputerFunctions/ComputerFunction.cs

@@ -0,0 +1,18 @@
+using SuperStarTrek.Space;
+
+namespace SuperStarTrek.Systems.ComputerFunctions
+{
+    internal abstract class ComputerFunction
+    {
+        protected ComputerFunction(string description, Output output)
+        {
+            Description = description;
+            Output = output;
+        }
+
+        internal string Description { get; }
+        protected Output Output { get; }
+
+        internal abstract void Execute(Quadrant quadrant);
+    }
+}

84 Super Star Trek/csharp/Systems/ComputerFunctions/CumulativeGalacticRecord.cs

@@ -0,0 +1,21 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using SuperStarTrek.Space;
+
+namespace SuperStarTrek.Systems.ComputerFunctions
+{
+    internal class CumulativeGalacticRecord : GalacticReport
+    {
+        internal CumulativeGalacticRecord(Output output, Galaxy galaxy)
+            : base("Cumulative galactic record", output, galaxy)
+        {
+        }
+
+        protected override void WriteHeader(Quadrant quadrant) =>
+            Output.NextLine().WriteLine($"Computer record of galaxy for quadrant {quadrant.Coordinates}").NextLine();
+
+        protected override IEnumerable<string> GetRowData() =>
+            Galaxy.Quadrants.Select(row => " " + string.Join("   ", row));
+    }
+}

84 Super Star Trek/csharp/Systems/ComputerFunctions/DirectionDistanceCalculator.cs

@@ -0,0 +1,33 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using SuperStarTrek.Objects;
+using SuperStarTrek.Space;
+
+namespace SuperStarTrek.Systems.ComputerFunctions
+{
+    internal class DirectionDistanceCalculator : NavigationCalculator
+    {
+        private readonly Enterprise _enterprise;
+        private readonly Input _input;
+
+        public DirectionDistanceCalculator(Enterprise enterprise, Output output, Input input)
+            : base("Starbase nav data", output)
+        {
+            _enterprise = enterprise;
+            _input = input;
+        }
+
+        internal override void Execute(Quadrant quadrant)
+        {
+            Output.WriteLine("Direction/distance calculator:")
+                .Write($"You are at quadrant {_enterprise.QuadrantCoordinates}")
+                .WriteLine($" sector {_enterprise.SectorCoordinates}")
+                .WriteLine("Please enter");
+
+            WriteDirectionAndDistance(
+                _input.GetCoordinates("  Initial coordinates"),
+                _input.GetCoordinates("  Final coordinates"));
+        }
+    }
+}

84 Super Star Trek/csharp/Systems/ComputerFunctions/GalacticReport.cs

@@ -0,0 +1,34 @@
+using System.Collections.Generic;
+using System.Linq;
+using SuperStarTrek.Space;
+
+namespace SuperStarTrek.Systems.ComputerFunctions
+{
+    internal abstract class GalacticReport : ComputerFunction
+    {
+        public GalacticReport(string description, Output output, Galaxy galaxy)
+            : base(description, output)
+        {
+            Galaxy = galaxy;
+        }
+
+        protected Galaxy Galaxy { get; }
+
+        protected abstract void WriteHeader(Quadrant quadrant);
+
+        protected abstract IEnumerable<string> GetRowData();
+
+        internal sealed override void Execute(Quadrant quadrant)
+        {
+            WriteHeader(quadrant);
+            Output.WriteLine("       1     2     3     4     5     6     7     8")
+                .WriteLine("     ----- ----- ----- ----- ----- ----- ----- -----");
+
+            foreach (var (row, index) in GetRowData().Select((r, i) => (r, i)))
+            {
+                Output.WriteLine($" {index+1}   {row}")
+                    .WriteLine("     ----- ----- ----- ----- ----- ----- ----- -----");
+            }
+        }
+    }
+}

84 Super Star Trek/csharp/Systems/ComputerFunctions/GalaxyRegionMap.cs

@@ -0,0 +1,21 @@
+using System.Collections.Generic;
+using System.Linq;
+using SuperStarTrek.Resources;
+using SuperStarTrek.Space;
+
+namespace SuperStarTrek.Systems.ComputerFunctions
+{
+    internal class GalaxyRegionMap : GalacticReport
+    {
+        internal GalaxyRegionMap(Output output, Galaxy galaxy)
+            : base("Galaxy 'region name' map", output, galaxy)
+        {
+        }
+
+        protected override void WriteHeader(Quadrant quadrant) =>
+            Output.WriteLine("                        The Galaxy");
+
+        protected override IEnumerable<string> GetRowData() =>
+            Strings.RegionNames.Split('\n').Select(n => n.TrimEnd('\r'));
+    }
+}

84 Super Star Trek/csharp/Systems/ComputerFunctions/NavigationCalculator.cs

@@ -0,0 +1,29 @@
+using SuperStarTrek.Space;
+using SuperStarTrek.Utils;
+
+namespace SuperStarTrek.Systems.ComputerFunctions
+{
+    internal abstract class NavigationCalculator : ComputerFunction
+    {
+        protected NavigationCalculator(string description, Output output)
+            : base(description, output)
+        {
+        }
+
+        protected void WriteDirectionAndDistance(Coordinates from, Coordinates to)
+        {
+            var (direction, distance) = from.GetDirectionAndDistanceTo(to);
+            Write(direction, distance);
+        }
+
+        protected void WriteDirectionAndDistance((float X, float Y) from, (float X, float Y) to)
+        {
+            var (direction, distance) = DirectionAndDistance.From(from.X, from.Y).To(to.X, to.Y);
+            Write(direction, distance);
+        }
+
+        private void Write(float direction, float distance) =>
+            Output.WriteLine($"Direction = {direction}")
+                .WriteLine($"Distance = {distance}");
+    }
+}

84 Super Star Trek/csharp/Systems/ComputerFunctions/StarbaseDataCalculator.cs

@@ -0,0 +1,30 @@
+using SuperStarTrek.Objects;
+using SuperStarTrek.Resources;
+using SuperStarTrek.Space;
+
+namespace SuperStarTrek.Systems.ComputerFunctions
+{
+    internal class StarbaseDataCalculator : NavigationCalculator
+    {
+        private readonly Enterprise _enterprise;
+
+        public StarbaseDataCalculator(Enterprise enterprise, Output output)
+            : base("Starbase nav data", output)
+        {
+            _enterprise = enterprise;
+        }
+
+        internal override void Execute(Quadrant quadrant)
+        {
+            if (!quadrant.HasStarbase)
+            {
+                Output.WriteLine(Strings.NoStarbase);
+                return;
+            }
+
+            Output.WriteLine("From Enterprise to Starbase:");
+
+            WriteDirectionAndDistance(_enterprise.SectorCoordinates, quadrant.Starbase.Sector);
+        }
+    }
+}

84 Super Star Trek/csharp/Systems/ComputerFunctions/StatusReport.cs

@@ -0,0 +1,41 @@
+using SuperStarTrek.Commands;
+using SuperStarTrek.Objects;
+using SuperStarTrek.Space;
+
+namespace SuperStarTrek.Systems.ComputerFunctions
+{
+    internal class StatusReport : ComputerFunction
+    {
+        private readonly Game _game;
+        private readonly Galaxy _galaxy;
+        private readonly Enterprise _enterprise;
+
+        public StatusReport(Game game, Galaxy galaxy, Enterprise enterprise, Output output)
+            : base("Status report", output)
+        {
+            _game = game;
+            _galaxy = galaxy;
+            _enterprise = enterprise;
+        }
+
+        internal override void Execute(Quadrant quadrant)
+        {
+            Output.WriteLine("   Status report:")
+                .Write("Klingon".Pluralize(_galaxy.KlingonCount)).WriteLine($" left:  {_galaxy.KlingonCount}")
+                .WriteLine($"Mission must be completed in {_game.StardatesRemaining:0.#} stardates.");
+
+            if (_galaxy.StarbaseCount > 0)
+            {
+                Output.Write($"The Federation is maintaining {_galaxy.StarbaseCount} ")
+                   .Write("starbase".Pluralize(_galaxy.StarbaseCount)).WriteLine(" in the galaxy.");
+            }
+            else
+            {
+                Output.WriteLine("Your stupidity has left you on your own in")
+                    .WriteLine("  the galaxy -- you have no starbases left!");
+            }
+
+            _enterprise.Execute(Command.DAM);
+        }
+    }
+}

84 Super Star Trek/csharp/Systems/ComputerFunctions/TorpedoDataCalculator.cs

@@ -0,0 +1,33 @@
+using SuperStarTrek.Objects;
+using SuperStarTrek.Resources;
+using SuperStarTrek.Space;
+
+namespace SuperStarTrek.Systems.ComputerFunctions
+{
+    internal class TorpedoDataCalculator : NavigationCalculator
+    {
+        private readonly Enterprise _enterprise;
+
+        public TorpedoDataCalculator(Enterprise enterprise, Output output)
+            : base("Photon torpedo data", output)
+        {
+            _enterprise = enterprise;
+        }
+
+        internal override void Execute(Quadrant quadrant)
+        {
+            if (!quadrant.HasKlingons)
+            {
+                Output.WriteLine(Strings.NoEnemyShips);
+                return;
+            }
+
+            Output.WriteLine("From Enterprise to Klingon battle cruiser".Pluralize(quadrant.KlingonCount));
+
+            foreach (var klingon in quadrant.Klingons)
+            {
+                WriteDirectionAndDistance(_enterprise.SectorCoordinates, klingon.Sector);
+            }
+        }
+    }
+}

84 Super Star Trek/csharp/Systems/DamageControl.cs

@@ -0,0 +1,54 @@
+using SuperStarTrek.Commands;
+using SuperStarTrek.Objects;
+using SuperStarTrek.Space;
+
+namespace SuperStarTrek.Systems
+{
+    internal class DamageControl : Subsystem
+    {
+        private readonly Enterprise _enterprise;
+        private readonly Output _output;
+
+        public DamageControl(Enterprise enterprise, Output output)
+            : base("Damage Control", Command.DAM, output)
+        {
+            _enterprise = enterprise;
+            _output = output;
+        }
+
+        protected override CommandResult ExecuteCommandCore(Quadrant quadrant)
+        {
+            if (IsDamaged)
+            {
+                _output.WriteLine("Damage Control report not available");
+            }
+            else
+            {
+                _output.NextLine();
+                WriteDamageReport();
+            }
+
+            if (_enterprise.DamagedSystemCount > 0 && _enterprise.IsDocked)
+            {
+                if (quadrant.Starbase.TryRepair(_enterprise, out var repairTime))
+                {
+                    WriteDamageReport();
+                    return CommandResult.Elapsed(repairTime);
+                }
+            }
+
+            return CommandResult.Ok;
+        }
+
+        public void WriteDamageReport()
+        {
+            _output.NextLine().WriteLine("Device             State of Repair");
+            foreach (var system in _enterprise.Systems)
+            {
+                _output.Write(system.Name.PadRight(25))
+                    .WriteLine(((int)(system.Condition * 100) * 0.01).ToString(" 0.##;-0.##"));
+            }
+            _output.NextLine();
+        }
+    }
+}

84 Super Star Trek/csharp/Systems/LibraryComputer.cs

@@ -0,0 +1,47 @@
+using SuperStarTrek.Commands;
+using SuperStarTrek.Space;
+using SuperStarTrek.Systems.ComputerFunctions;
+
+namespace SuperStarTrek.Systems
+{
+    internal class LibraryComputer : Subsystem
+    {
+        private readonly Output _output;
+        private readonly Input _input;
+        private readonly ComputerFunction[] _functions;
+
+        public LibraryComputer(Output output, Input input, params ComputerFunction[] functions)
+            : base("Library-Computer", Command.COM, output)
+        {
+            _output = output;
+            _input = input;
+            _functions = functions;
+        }
+
+        protected override bool CanExecuteCommand() => IsOperational("Computer disabled");
+
+        protected override CommandResult ExecuteCommandCore(Quadrant quadrant)
+        {
+            var index = GetFunctionIndex();
+            _output.NextLine();
+
+            _functions[index].Execute(quadrant);
+
+            return CommandResult.Ok;
+        }
+
+        private int GetFunctionIndex()
+        {
+            while (true)
+            {
+                var index = (int)_input.GetNumber("Computer active and waiting command");
+                if (index >= 0 && index <= 5) { return index; }
+
+                for (int i = 0; i < _functions.Length; i++)
+                {
+                    _output.WriteLine($"   {i} = {_functions[i].Description}");
+                }
+            }
+        }
+    }
+}

84 Super Star Trek/csharp/Systems/LongRangeSensors.cs

@@ -0,0 +1,39 @@
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using SuperStarTrek.Commands;
+using SuperStarTrek.Objects;
+using SuperStarTrek.Resources;
+using SuperStarTrek.Space;
+
+namespace SuperStarTrek.Systems
+{
+    internal class LongRangeSensors : Subsystem
+    {
+        private readonly Galaxy _galaxy;
+        private readonly Output _output;
+
+        public LongRangeSensors(Galaxy galaxy, Output output)
+            : base("Long Range Sensors", Command.LRS, output)
+        {
+            _galaxy = galaxy;
+            _output = output;
+        }
+
+        protected override bool CanExecuteCommand() => IsOperational("{name} are inoperable");
+
+        protected override CommandResult ExecuteCommandCore(Quadrant quadrant)
+        {
+            _output.WriteLine($"Long range scan for quadrant {quadrant.Coordinates}");
+            _output.WriteLine("-------------------");
+            foreach (var quadrants in _galaxy.GetNeighborhood(quadrant))
+            {
+                _output.WriteLine(": " + string.Join(" : ", quadrants.Select(q => q?.Scan() ?? "***")) + " :");
+                _output.WriteLine("-------------------");
+            }
+
+            return CommandResult.Ok;
+        }
+    }
+}

84 Super Star Trek/csharp/Systems/PhaserControl.cs

@@ -0,0 +1,97 @@
+using System.Linq;
+using SuperStarTrek.Commands;
+using SuperStarTrek.Objects;
+using SuperStarTrek.Resources;
+using SuperStarTrek.Space;
+
+namespace SuperStarTrek.Systems
+{
+    internal class PhaserControl : Subsystem
+    {
+        private readonly Enterprise _enterprise;
+        private readonly Output _output;
+        private readonly Input _input;
+        private readonly Random _random;
+
+        public PhaserControl(Enterprise enterprise, Output output, Input input, Random random)
+            : base("Phaser Control", Command.PHA, output)
+        {
+            _enterprise = enterprise;
+            _output = output;
+            _input = input;
+            _random = random;
+        }
+
+        protected override bool CanExecuteCommand() => IsOperational("Phasers inoperative");
+
+        protected override CommandResult ExecuteCommandCore(Quadrant quadrant)
+        {
+            if (!quadrant.HasKlingons)
+            {
+                _output.WriteLine(Strings.NoEnemyShips);
+                return CommandResult.Ok;
+            }
+
+            if (_enterprise.Computer.IsDamaged)
+            {
+                _output.WriteLine("Computer failure hampers accuracy");
+            }
+
+            _output.Write($"Phasers locked on target;  ");
+
+            var phaserStrength = GetPhaserStrength();
+            if (phaserStrength < 0) { return CommandResult.Ok; }
+
+            _enterprise.UseEnergy(phaserStrength);
+
+            var perEnemyStrength = GetPerTargetPhaserStrength(phaserStrength, quadrant.KlingonCount);
+
+            foreach (var klingon in quadrant.Klingons.ToList())
+            {
+                ResolveHitOn(klingon, perEnemyStrength, quadrant);
+            }
+
+            return quadrant.KlingonsFireOnEnterprise();
+        }
+
+        private float GetPhaserStrength()
+        {
+            while (true)
+            {
+                _output.WriteLine($"Energy available = {_enterprise.Energy} units");
+                var phaserStrength = _input.GetNumber("Number of units to fire");
+
+                if (phaserStrength <= _enterprise.Energy) { return phaserStrength; }
+            }
+        }
+
+        private float GetPerTargetPhaserStrength(float phaserStrength, int targetCount)
+        {
+            if (_enterprise.Computer.IsDamaged)
+            {
+                phaserStrength *= _random.GetFloat();
+            }
+
+            return phaserStrength / targetCount;
+        }
+
+        private void ResolveHitOn(Klingon klingon, float perEnemyStrength, Quadrant quadrant)
+        {
+            var distance = _enterprise.SectorCoordinates.GetDistanceTo(klingon.Sector);
+            var hitStrength = (int)(perEnemyStrength / distance * (2 + _random.GetFloat()));
+
+            if (klingon.TakeHit(hitStrength))
+            {
+                _output.WriteLine($"{hitStrength} unit hit on Klingon at sector {klingon.Sector}");
+                _output.WriteLine(
+                    klingon.Energy <= 0
+                        ? quadrant.Remove(klingon)
+                        : $"   (sensors show {klingon.Energy} units remaining)");
+            }
+            else
+            {
+                _output.WriteLine($"Sensors show no damage to enemy at {klingon.Sector}");
+            }
+        }
+    }
+}

84 Super Star Trek/csharp/Systems/PhotonTubes.cs

@@ -0,0 +1,66 @@
+using SuperStarTrek.Commands;
+using SuperStarTrek.Objects;
+using SuperStarTrek.Space;
+
+namespace SuperStarTrek.Systems
+{
+    internal class PhotonTubes : Subsystem
+    {
+        private readonly int _tubeCount;
+        private readonly Enterprise _enterprise;
+        private readonly Output _output;
+        private readonly Input _input;
+
+        public PhotonTubes(int tubeCount, Enterprise enterprise, Output output, Input input)
+            : base("Photon Tubes", Command.TOR, output)
+        {
+            TorpedoCount = _tubeCount = tubeCount;
+            _enterprise = enterprise;
+            _output = output;
+            _input = input;
+        }
+
+        public int TorpedoCount { get; private set; }
+
+        protected override bool CanExecuteCommand() => HasTorpedoes() && IsOperational("{name} are not operational");
+
+        private bool HasTorpedoes()
+        {
+            if (TorpedoCount > 0) { return true; }
+
+            _output.WriteLine("All photon torpedoes expended");
+            return false;
+        }
+
+        protected override CommandResult ExecuteCommandCore(Quadrant quadrant)
+        {
+            if (!_input.TryGetCourse("Photon torpedo course", "Ensign Chekov", out var course))
+            {
+                return CommandResult.Ok;
+            }
+
+            TorpedoCount -= 1;
+
+            var isHit = false;
+            _output.WriteLine("Torpedo track:");
+            foreach (var sector in course.GetSectorsFrom(_enterprise.SectorCoordinates))
+            {
+                _output.WriteLine($"                {sector}");
+
+                if (quadrant.TorpedoCollisionAt(sector, out var message, out var gameOver))
+                {
+                    _output.WriteLine(message);
+                    isHit = true;
+                    if (gameOver) { return CommandResult.GameOver; }
+                    break;
+                }
+            }
+
+            if (!isHit) { _output.WriteLine("Torpedo missed!"); }
+
+            return quadrant.KlingonsFireOnEnterprise();
+        }
+
+        internal void ReplenishTorpedoes() => TorpedoCount = _tubeCount;
+    }
+}

84 Super Star Trek/csharp/Systems/ShieldControl.cs

@@ -1,3 +1,4 @@
+using SuperStarTrek.Commands;
 using SuperStarTrek.Objects;
 using SuperStarTrek.Space;
 
@@ -10,36 +11,35 @@ namespace SuperStarTrek.Systems
         private readonly Input _input;
 
         public ShieldControl(Enterprise enterprise, Output output, Input input)
-            : base("Shield Control", Command.SHE)
+            : base("Shield Control", Command.SHE, output)
         {
             _enterprise = enterprise;
             _output = output;
             _input = input;
         }
 
-        public double Energy { get; private set; }
+        public float ShieldEnergy { get; set; }
 
-        public override void ExecuteCommand(Quadrant quadrant)
+        protected override bool CanExecuteCommand() => IsOperational("{name} inoperable");
+
+        protected override CommandResult ExecuteCommandCore(Quadrant quadrant)
         {
-            if (Condition < 0)
-            {
-                _output.WriteLine("Shield Control inoperable");
-                return;
-            }
-
             _output.WriteLine($"Energy available = {_enterprise.TotalEnergy}");
             var requested = _input.GetNumber($"Number of units to shields");
 
             if (Validate(requested))
             {
-                Energy = requested;
+                ShieldEnergy = requested;
-                return;
+            }
+            else
+            {
+                _output.WriteLine("<SHIELDS UNCHANGED>");
             }
 
-            _output.WriteLine("<SHIELDS UNCHANGED>");
+            return CommandResult.Ok;
         }
 
-        private bool Validate(double requested)
+        private bool Validate(float requested)
         {
             if (requested > _enterprise.TotalEnergy)
             {
@@ -47,7 +47,11 @@ namespace SuperStarTrek.Systems
                 return false;
             }
 
-            return requested >= 0 && requested != Energy;
+            return requested >= 0 && requested != ShieldEnergy;
         }
+
+        internal void AbsorbHit(int hitStrength) => ShieldEnergy -= hitStrength;
+
+        internal void DropShields() => ShieldEnergy = 0;
     }
 }

84 Super Star Trek/csharp/Systems/ShortRangeSensors.cs

@@ -2,6 +2,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using SuperStarTrek.Commands;
 using SuperStarTrek.Objects;
 using SuperStarTrek.Resources;
 using SuperStarTrek.Space;
@@ -16,7 +17,7 @@ namespace SuperStarTrek.Systems
         private readonly Output _output;
 
         public ShortRangeSensors(Enterprise enterprise, Galaxy galaxy, Game game, Output output)
-            : base("Short Range Sensors", Command.SRS)
+            : base("Short Range Sensors", Command.SRS, output)
         {
             _enterprise = enterprise;
             _galaxy = galaxy;
@@ -24,7 +25,7 @@ namespace SuperStarTrek.Systems
             _output = output;
         }
 
-        public override void ExecuteCommand(Quadrant quadrant)
+        protected override CommandResult ExecuteCommandCore(Quadrant quadrant)
         {
             if (_enterprise.IsDocked)
             {
@@ -42,17 +43,19 @@ namespace SuperStarTrek.Systems
                 .ToList()
                 .ForEach(l => _output.WriteLine(l));
             _output.WriteLine("---------------------------------");
+
+            return CommandResult.Ok;
         }
 
         public IEnumerable<string> GetStatusLines()
         {
             yield return $"Stardate           {_game.Stardate}";
             yield return $"Condition          {_enterprise.Condition}";
-            yield return $"Quadrant           {_enterprise.Quadrant}";
+            yield return $"Quadrant           {_enterprise.QuadrantCoordinates}";
-            yield return $"Sector             {_enterprise.Sector}";
+            yield return $"Sector             {_enterprise.SectorCoordinates}";
-            yield return $"Photon torpedoes   {_enterprise.TorpedoCount}";
+            yield return $"Photon torpedoes   {_enterprise.PhotonTubes.TorpedoCount}";
-            yield return $"Total energy       {Math.Ceiling(_enterprise.Energy)}";
+            yield return $"Total energy       {Math.Ceiling(_enterprise.TotalEnergy)}";
-            yield return $"Shields            {(int)_enterprise.Shields}";
+            yield return $"Shields            {(int)_enterprise.ShieldControl.ShieldEnergy}";
             yield return $"Klingons remaining {_galaxy.KlingonCount}";
         }
     }

84 Super Star Trek/csharp/Systems/Subsystem.cs

@@ -1,20 +1,66 @@
+using System;
+using SuperStarTrek.Commands;
 using SuperStarTrek.Space;
 
 namespace SuperStarTrek.Systems
 {
     internal abstract class Subsystem
     {
-        protected Subsystem(string name, Command command)
+        private readonly Output _output;
+
+        protected Subsystem(string name, Command command, Output output)
         {
             Name = name;
             Command = command;
             Condition = 0;
+            _output = output;
         }
 
         public string Name { get; }
-        public double Condition { get; }
+        public float Condition { get; private set; }
+        public bool IsDamaged => Condition < 0;
         public Command Command { get; }
 
-        public abstract void ExecuteCommand(Quadrant quadrant);
+        protected virtual bool CanExecuteCommand() => true;
+
+        protected bool IsOperational(string notOperationalMessage)
+        {
+            if (IsDamaged)
+            {
+                _output.WriteLine(notOperationalMessage.Replace("{name}", Name));
+                return false;
+            }
+
+            return true;
+        }
+
+        public CommandResult ExecuteCommand(Quadrant quadrant)
+            => CanExecuteCommand() ? ExecuteCommandCore(quadrant) : CommandResult.Ok;
+
+        protected abstract CommandResult ExecuteCommandCore(Quadrant quadrant);
+
+        public virtual void Repair()
+        {
+            if (IsDamaged)
+            {
+                Condition = 0;
+            }
+        }
+
+        public virtual bool Repair(float repairWorkDone)
+        {
+            if (IsDamaged)
+            {
+                Condition += repairWorkDone;
+                if (Condition > -0.1f && Condition < 0)
+                {
+                    Condition = -0.1f;
+                }
+            }
+
+            return !IsDamaged;
+        }
+
+        internal void TakeDamage(float damage) => Condition -= damage;
     }
 }

84 Super Star Trek/csharp/Systems/WarpEngines.cs

@@ -0,0 +1,82 @@
+using System;
+using SuperStarTrek.Commands;
+using SuperStarTrek.Objects;
+using SuperStarTrek.Space;
+
+namespace SuperStarTrek.Systems
+{
+    internal class WarpEngines : Subsystem
+    {
+        private readonly Enterprise _enterprise;
+        private readonly Output _output;
+        private readonly Input _input;
+
+        public WarpEngines(Enterprise enterprise, Output output, Input input)
+            : base("Warp Engines", Command.NAV, output)
+        {
+            _enterprise = enterprise;
+            _output = output;
+            _input = input;
+        }
+
+        protected override CommandResult ExecuteCommandCore(Quadrant quadrant)
+        {
+            if (_input.TryGetCourse("Course", "   Lt. Sulu", out var course) &&
+                TryGetWarpFactor(out var warpFactor) &&
+                TryGetDistanceToMove(warpFactor, out var distanceToMove))
+            {
+                var result = quadrant.KlingonsMoveAndFire();
+                if (result.IsGameOver) { return result; }
+
+                _enterprise.RepairSystems(warpFactor);
+                _enterprise.VaryConditionOfRandomSystem();
+                var timeElapsed = _enterprise.Move(course, warpFactor, distanceToMove);
+
+                if (_enterprise.IsDocked)
+                {
+                    _enterprise.ShieldControl.DropShields();
+                    _enterprise.Refuel();
+                    _enterprise.PhotonTubes.ReplenishTorpedoes();
+                }
+
+                return CommandResult.Elapsed(timeElapsed);
+            }
+
+            return CommandResult.Ok;
+        }
+
+        private bool TryGetWarpFactor(out float warpFactor)
+        {
+            var maximumWarp = IsDamaged ? 0.2f : 8;
+            if (_input.TryGetNumber("Warp Factor", 0, maximumWarp, out warpFactor))
+            {
+                return warpFactor > 0;
+            }
+
+            _output.WriteLine(
+                IsDamaged && warpFactor > maximumWarp
+                    ? "Warp engines are damaged.  Maximum speed = warp 0.2"
+                    : $"  Chief Engineer Scott reports, 'The engines won't take warp {warpFactor} !'");
+
+            return false;
+        }
+
+        private bool TryGetDistanceToMove(float warpFactor, out int distanceToTravel)
+        {
+            distanceToTravel = (int)Math.Round(warpFactor * 8, MidpointRounding.AwayFromZero);
+            if (distanceToTravel <= _enterprise.Energy) { return true; }
+
+            _output.WriteLine("Engineering reports, 'Insufficient energy available")
+                .WriteLine($"                      for maneuvering at warp {warpFactor} !'");
+
+            if (distanceToTravel <= _enterprise.TotalEnergy && !_enterprise.ShieldControl.IsDamaged)
+            {
+                _output.Write($"Deflector control room acknowledges {_enterprise.ShieldControl.ShieldEnergy} ")
+                    .WriteLine("units of energy")
+                    .WriteLine("                         presently deployed to shields.");
+            }
+
+            return false;
+        }
+    }
+}

84 Super Star Trek/csharp/Utils/DirectionAndDistance.cs

@@ -0,0 +1,65 @@
+using System;
+using SuperStarTrek.Space;
+
+namespace SuperStarTrek.Utils
+{
+    internal class DirectionAndDistance
+    {
+        private readonly float _fromX;
+        private readonly float _fromY;
+
+        private DirectionAndDistance(float fromX, float fromY)
+        {
+            _fromX = fromX;
+            _fromY = fromY;
+        }
+
+        public static DirectionAndDistance From(Coordinates coordinates) => From(coordinates.X, coordinates.Y);
+
+        public static DirectionAndDistance From(float x, float y) => new DirectionAndDistance(x, y);
+
+        public (float Direction, float Distance) To(Coordinates coordinates) => To(coordinates.X, coordinates.Y);
+
+        public (float Direction, float Distance) To(float x, float y)
+        {
+            var deltaX = x - _fromX;
+            var deltaY = y - _fromY;
+
+            return (GetDirection(deltaX, deltaY), GetDistance(deltaX, deltaY));
+        }
+
+        // The algorithm here is mathematically equivalent to the following code in the original,
+        // where X is deltaY and A is deltaX
+        //     8220 X=X-A:A=C1-W1:IFX<0THEN8350
+        //     8250 IFA<0THEN8410
+        //     8260 IFX>0THEN8280
+        //     8270 IFA=0THENC1=5:GOTO8290
+        //     8280 C1=1
+        //     8290 IFABS(A)<=ABS(X)THEN8330
+        //     8310 PRINT"DIRECTION =";C1+(((ABS(A)-ABS(X))+ABS(A))/ABS(A)):GOTO8460
+        //     8330 PRINT"DIRECTION =";C1+(ABS(A)/ABS(X)):GOTO8460
+        //     8350 IFA>0THENC1=3:GOTO8420
+        //     8360 IFX<>0THENC1=5:GOTO8290
+        //     8410 C1=7
+        //     8420 IFABS(A)>=ABS(X)THEN8450
+        //     8430 PRINT"DIRECTION =";C1+(((ABS(X)-ABS(A))+ABS(X))/ABS(X)):GOTO8460
+        //     8450 PRINT"DIRECTION =";C1+(ABS(X)/ABS(A))
+        //     8460 PRINT"DISTANCE =";SQR(X^2+A^2):IFH8=1THEN1990
+        private float GetDirection(float deltaX, float deltaY)
+        {
+            var deltaXDominant = Math.Abs(deltaX) > Math.Abs(deltaY);
+            var fractionalPart = deltaXDominant ? deltaY / deltaX : -deltaX / deltaY;
+            var nearestCardinal = deltaXDominant switch
+            {
+                true => deltaX > 0 ? 7 : 3,
+                false => deltaY > 0 ? 1 : 5
+            };
+
+            var direction = nearestCardinal + fractionalPart;
+            return direction < 1 ? direction + 8 : direction;
+        }
+
+        private float GetDistance(float deltaX, float deltaY) =>
+            (float)Math.Sqrt(Math.Pow(deltaX, 2) + Math.Pow(deltaY, 2));
+    }
+}