Merge pull request #386 from daves561/bombs-away-csharp

Bombs Away in C#

12_Bombs_Away/csharp/BombsAway.sln

@@ -0,0 +1,31 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.0.32014.148
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "BombsAwayConsole", "BombsAwayConsole\BombsAwayConsole.csproj", "{D80015FA-423C-4A16-AA2B-16669245AD59}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "BombsAwayGame", "BombsAwayGame\BombsAwayGame.csproj", "{F57AEC18-FEE9-4F08-9F20-DFC56EFE6BFC}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{D80015FA-423C-4A16-AA2B-16669245AD59}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{D80015FA-423C-4A16-AA2B-16669245AD59}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{D80015FA-423C-4A16-AA2B-16669245AD59}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{D80015FA-423C-4A16-AA2B-16669245AD59}.Release|Any CPU.Build.0 = Release|Any CPU
+		{F57AEC18-FEE9-4F08-9F20-DFC56EFE6BFC}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{F57AEC18-FEE9-4F08-9F20-DFC56EFE6BFC}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{F57AEC18-FEE9-4F08-9F20-DFC56EFE6BFC}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{F57AEC18-FEE9-4F08-9F20-DFC56EFE6BFC}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {39B2ECFB-037D-4335-BBD2-64892E953DD4}
+	EndGlobalSection
+EndGlobal

12_Bombs_Away/csharp/BombsAwayConsole/BombsAwayConsole.csproj

@@ -0,0 +1,14 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\BombsAwayGame\BombsAwayGame.csproj" />
+  </ItemGroup>
+
+</Project>

12_Bombs_Away/csharp/BombsAwayConsole/ConsoleUserInterface.cs

@@ -0,0 +1,134 @@
+namespace BombsAwayConsole;
+
+/// <summary>
+/// Implements <see cref="BombsAwayGame.IUserInterface"/> by writing to and reading from <see cref="Console"/>.
+/// </summary>
+internal class ConsoleUserInterface : BombsAwayGame.IUserInterface
+{
+    /// <summary>
+    /// Write message to console.
+    /// </summary>
+    /// <param name="message">Message to display.</param>
+    public void Output(string message)
+    {
+        Console.WriteLine(message);
+    }
+
+    /// <summary>
+    /// Write choices with affixed indexes, allowing the user to choose by index.
+    /// </summary>
+    /// <param name="message">Message to display.</param>
+    /// <param name="choices">Choices to display.</param>
+    /// <returns>Choice that user picked.</returns>
+    public int Choose(string message, IList<string> choices)
+    {
+        IEnumerable<string> choicesWithIndexes = choices.Select((choice, index) => $"{choice}({index + 1})");
+        string choiceText = string.Join(", ", choicesWithIndexes);
+        Output($"{message} -- {choiceText}");
+
+        ISet<ConsoleKey> allowedKeys = ConsoleKeysFromList(choices);
+        ConsoleKey? choice;
+        do
+        {
+            choice = ReadChoice(allowedKeys);
+            if (choice is null)
+            {
+                Output("TRY AGAIN...");
+            }
+        }
+        while (choice is null);
+
+        return ListIndexFromConsoleKey(choice.Value);
+    }
+
+    /// <summary>
+    /// Convert the given list to its <see cref="ConsoleKey"/> equivalents. This generates keys that map
+    /// the first element to <see cref="ConsoleKey.D1"/>, the second element to <see cref="ConsoleKey.D2"/>,
+    /// and so on, up to the last element of the list.
+    /// </summary>
+    /// <param name="list">List whose elements will be converted to <see cref="ConsoleKey"/> equivalents.</param>
+    /// <returns><see cref="ConsoleKey"/> equivalents from <paramref name="list"/>.</returns>
+    private ISet<ConsoleKey> ConsoleKeysFromList(IList<string> list)
+    {
+        IEnumerable<int> indexes = Enumerable.Range((int)ConsoleKey.D1, list.Count);
+        return new HashSet<ConsoleKey>(indexes.Cast<ConsoleKey>());
+    }
+
+    /// <summary>
+    /// Convert the given console key to its list index equivalent. This assumes the key was generated from
+    /// <see cref="ConsoleKeysFromList(IList{string})"/>
+    /// </summary>
+    /// <param name="key">Key to convert to its list index equivalent.</param>
+    /// <returns>List index equivalent of key.</returns>
+    private int ListIndexFromConsoleKey(ConsoleKey key)
+    {
+        return key - ConsoleKey.D1;
+    }
+
+    /// <summary>
+    /// Read a key from the console and return it if it is in the given allowed keys.
+    /// </summary>
+    /// <param name="allowedKeys">Allowed keys.</param>
+    /// <returns>Key read from <see cref="Console"/>, if it is in <paramref name="allowedKeys"/>; null otherwise./></returns>
+    private ConsoleKey? ReadChoice(ISet<ConsoleKey> allowedKeys)
+    {
+        ConsoleKeyInfo keyInfo = ReadKey();
+        return allowedKeys.Contains(keyInfo.Key) ? keyInfo.Key : null;
+    }
+
+    /// <summary>
+    /// Read key from <see cref="Console"/>.
+    /// </summary>
+    /// <returns>Key read from <see cref="Console"/>.</returns>
+    private ConsoleKeyInfo ReadKey()
+    {
+        ConsoleKeyInfo result = Console.ReadKey(intercept: false);
+        // Write a blank line to the console so the displayed key is on its own line.
+        Console.WriteLine();
+        return result;
+    }
+
+    /// <summary>
+    /// Allow user to choose 'Y' or 'N' from <see cref="Console"/>.
+    /// </summary>
+    /// <param name="message">Message to display.</param>
+    /// <returns>True if user chose 'Y', false if user chose 'N'.</returns>
+    public bool ChooseYesOrNo(string message)
+    {
+        Output(message);
+        ConsoleKey? choice;
+        do
+        {
+            choice = ReadChoice(new HashSet<ConsoleKey>(new[] { ConsoleKey.Y, ConsoleKey.N }));
+            if (choice is null)
+            {
+                Output("ENTER Y OR N");
+            }
+        }
+        while (choice is null);
+
+        return choice.Value == ConsoleKey.Y;
+    }
+
+    /// <summary>
+    /// Get integer by reading a line from <see cref="Console"/>.
+    /// </summary>
+    /// <returns>Integer read from <see cref="Console"/>.</returns>
+    public int InputInteger()
+    {
+        bool resultIsValid;
+        int result;
+        do
+        {
+            string? integerText = Console.ReadLine();
+            resultIsValid = int.TryParse(integerText, out result);
+            if (!resultIsValid)
+            {
+                Output("PLEASE ENTER A NUMBER");
+            }
+        }
+        while (!resultIsValid);
+
+        return result;
+    }
+}

12_Bombs_Away/csharp/BombsAwayConsole/Program.cs

@@ -0,0 +1,26 @@
+using BombsAwayConsole;
+using BombsAwayGame;
+
+/// Create and play <see cref="Game"/>s using a <see cref="ConsoleUserInterface"/>.
+PlayGameWhileUserWantsTo(new ConsoleUserInterface());
+
+void PlayGameWhileUserWantsTo(ConsoleUserInterface ui)
+{
+    do
+    {
+        new Game(ui).Play();
+    }
+    while (UserWantsToPlayAgain(ui));
+}
+
+bool UserWantsToPlayAgain(IUserInterface ui)
+{
+    bool result = ui.ChooseYesOrNo("ANOTHER MISSION (Y OR N)?");
+    if (!result)
+    {
+        Console.WriteLine("CHICKEN !!!");
+    }
+
+    return result;
+}
+

12_Bombs_Away/csharp/BombsAwayGame/AlliesSide.cs

@@ -0,0 +1,22 @@
+namespace BombsAwayGame;
+
+/// <summary>
+/// Allies protagonist. Can fly missions in a Liberator, B-29, B-17, or Lancaster.
+/// </summary>
+internal class AlliesSide : MissionSide
+{
+    public AlliesSide(IUserInterface ui)
+        : base(ui)
+    {
+    }
+
+    protected override string ChooseMissionMessage => "AIRCRAFT";
+
+    protected override IList<Mission> AllMissions => new Mission[]
+    {
+        new("LIBERATOR", "YOU'VE GOT 2 TONS OF BOMBS FLYING FOR PLOESTI."),
+        new("B-29", "YOU'RE DUMPING THE A-BOMB ON HIROSHIMA."),
+        new("B-17", "YOU'RE CHASING THE BISMARK IN THE NORTH SEA."),
+        new("LANCASTER", "YOU'RE BUSTING A GERMAN HEAVY WATER PLANT IN THE RUHR.")
+    };
+}

12_Bombs_Away/csharp/BombsAwayGame/BombsAwayGame.csproj

@@ -0,0 +1,9 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>

12_Bombs_Away/csharp/BombsAwayGame/EnemyArtillery.cs

@@ -0,0 +1,8 @@
+namespace BombsAwayGame;
+
+/// <summary>
+/// Represents enemy artillery.
+/// </summary>
+/// <param name="Name">Name of artillery type.</param>
+/// <param name="Accuracy">Accuracy of artillery. This is the `T` variable in the original BASIC.</param>
+internal record class EnemyArtillery(string Name, int Accuracy);

12_Bombs_Away/csharp/BombsAwayGame/Game.cs

@@ -0,0 +1,58 @@
+namespace BombsAwayGame;
+
+/// <summary>
+/// Plays the Bombs Away game using a supplied <see cref="IUserInterface"/>.
+/// </summary>
+public class Game
+{
+    private readonly IUserInterface _ui;
+
+    /// <summary>
+    /// Create game instance using the given UI.
+    /// </summary>
+    /// <param name="ui">UI to use for game.</param>
+    public Game(IUserInterface ui)
+    {
+        _ui = ui;
+    }
+
+    /// <summary>
+    /// Play game. Choose a side and play the side's logic.
+    /// </summary>
+    public void Play()
+    {
+        _ui.Output("YOU ARE A PILOT IN A WORLD WAR II BOMBER.");
+        Side side = ChooseSide();
+        side.Play();
+    }
+
+    /// <summary>
+    /// Represents a <see cref="Side"/>.
+    /// </summary>
+    /// <param name="Name">Name of side.</param>
+    /// <param name="CreateSide">Create instance of side that this descriptor represents.</param>
+    private record class SideDescriptor(string Name, Func<Side> CreateSide);
+
+    /// <summary>
+    /// Choose side and return a new instance of that side.
+    /// </summary>
+    /// <returns>New instance of side that was chosen.</returns>
+    private Side ChooseSide()
+    {
+        SideDescriptor[] sides = AllSideDescriptors;
+        string[] sideNames = sides.Select(a => a.Name).ToArray();
+        int index = _ui.Choose("WHAT SIDE", sideNames);
+        return sides[index].CreateSide();
+    }
+
+    /// <summary>
+    /// All side descriptors.
+    /// </summary>
+    private SideDescriptor[] AllSideDescriptors => new SideDescriptor[]
+    {
+        new("ITALY", () => new ItalySide(_ui)),
+        new("ALLIES", () => new AlliesSide(_ui)),
+        new("JAPAN", () => new JapanSide(_ui)),
+        new("GERMANY", () => new GermanySide(_ui)),
+    };
+}

12_Bombs_Away/csharp/BombsAwayGame/GermanySide.cs

@@ -0,0 +1,21 @@
+namespace BombsAwayGame;
+
+/// <summary>
+/// Germany protagonist. Can fly missions to Russia, England, and France.
+/// </summary>
+internal class GermanySide : MissionSide
+{
+    public GermanySide(IUserInterface ui)
+        : base(ui)
+    {
+    }
+
+    protected override string ChooseMissionMessage => "A NAZI, EH?  OH WELL.  ARE YOU GOING FOR";
+
+    protected override IList<Mission> AllMissions => new Mission[]
+    {
+        new("RUSSIA", "YOU'RE NEARING STALINGRAD."),
+        new("ENGLAND", "NEARING LONDON.  BE CAREFUL, THEY'VE GOT RADAR."),
+        new("FRANCE", "NEARING VERSAILLES.  DUCK SOUP.  THEY'RE NEARLY DEFENSELESS.")
+    };
+}

12_Bombs_Away/csharp/BombsAwayGame/IUserInterface.cs

@@ -0,0 +1,38 @@
+namespace BombsAwayGame;
+
+/// <summary>
+/// Represents an interface for supplying data to the game.
+/// </summary>
+/// <remarks>
+/// Abstracting the UI allows us to concentrate its concerns in one part of our code and to change UI behavior
+/// without creating any risk of changing the game logic. It also allows us to supply an automated UI for tests.
+/// </remarks>
+public interface IUserInterface
+{
+    /// <summary>
+    /// Display the given message.
+    /// </summary>
+    /// <param name="message">Message to display.</param>
+    void Output(string message);
+
+    /// <summary>
+    /// Choose an item from the given choices.
+    /// </summary>
+    /// <param name="message">Message to display.</param>
+    /// <param name="choices">Choices to choose from.</param>
+    /// <returns>Index of choice in <paramref name="choices"/> that user chose.</returns>
+    int Choose(string message, IList<string> choices);
+
+    /// <summary>
+    /// Allow user to choose Yes or No.
+    /// </summary>
+    /// <param name="message">Message to display.</param>
+    /// <returns>True if user chose Yes, false if user chose No.</returns>
+    bool ChooseYesOrNo(string message);
+
+    /// <summary>
+    /// Get integer from user.
+    /// </summary>
+    /// <returns>Integer supplied by user.</returns>
+    int InputInteger();
+}

12_Bombs_Away/csharp/BombsAwayGame/ItalySide.cs

@@ -0,0 +1,21 @@
+namespace BombsAwayGame;
+
+/// <summary>
+/// Italy protagonist. Can fly missions to Albania, Greece, and North Africa.
+/// </summary>
+internal class ItalySide : MissionSide
+{
+    public ItalySide(IUserInterface ui)
+        : base(ui)
+    {
+    }
+
+    protected override string ChooseMissionMessage => "YOUR TARGET";
+
+    protected override IList<Mission> AllMissions => new Mission[]
+    {
+        new("ALBANIA", "SHOULD BE EASY -- YOU'RE FLYING A NAZI-MADE PLANE."),
+        new("GREECE", "BE CAREFUL!!!"),
+        new("NORTH AFRICA", "YOU'RE GOING FOR THE OIL, EH?")
+    };
+}

12_Bombs_Away/csharp/BombsAwayGame/JapanSide.cs

@@ -0,0 +1,38 @@
+namespace BombsAwayGame;
+
+/// <summary>
+/// Japan protagonist. Flies a kamikaze mission, which has a different logic from <see cref="MissionSide"/>s.
+/// </summary>
+internal class JapanSide : Side
+{
+    public JapanSide(IUserInterface ui)
+        : base(ui)
+    {
+    }
+
+    /// <summary>
+    /// Perform a kamikaze mission. If first kamikaze mission, it will succeed 65% of the time. If it's not
+    /// first kamikaze mission, perform an enemy counterattack.
+    /// </summary>
+    public override void Play()
+    {
+        UI.Output("YOU'RE FLYING A KAMIKAZE MISSION OVER THE USS LEXINGTON.");
+
+        bool isFirstMission = UI.ChooseYesOrNo("YOUR FIRST KAMIKAZE MISSION(Y OR N)?");
+        if (!isFirstMission)
+        {
+            // LINE 207 of original BASIC: hitRatePercent is initialized to 0,
+            // but R, the type of artillery, is not initialized at all. Setting
+            // R = 1, which is to say EnemyArtillery = Guns, gives the same result.
+            EnemyCounterattack(Guns, hitRatePercent: 0);
+        }
+        else if (RandomFrac() > 0.65)
+        {
+            MissionSucceeded();
+        }
+        else
+        {
+            MissionFailed();
+        }
+    }
+}

12_Bombs_Away/csharp/BombsAwayGame/Mission.cs

@@ -0,0 +1,8 @@
+namespace BombsAwayGame;
+
+/// <summary>
+/// Represents a mission that can be flown by a <see cref="MissionSide"/>.
+/// </summary>
+/// <param name="Name">Name of mission.</param>
+/// <param name="Description">Description of mission.</param>
+internal record class Mission(string Name, string Description);

12_Bombs_Away/csharp/BombsAwayGame/MissionSide.cs

@@ -0,0 +1,208 @@
+namespace BombsAwayGame;
+
+/// <summary>
+/// Represents a protagonist that chooses a standard (non-kamikaze) mission.
+/// </summary>
+internal abstract class MissionSide : Side
+{
+    /// <summary>
+    /// Create instance using the given UI.
+    /// </summary>
+    /// <param name="ui">UI to use.</param>
+    public MissionSide(IUserInterface ui)
+        : base(ui)
+    {
+    }
+
+    /// <summary>
+    /// Reasonable upper bound for missions flown previously.
+    /// </summary>
+    private const int MaxMissionCount = 160;
+
+    /// <summary>
+    /// Choose a mission and attempt it. If attempt fails, perform an enemy counterattack.
+    /// </summary>
+    public override void Play()
+    {
+        Mission mission = ChooseMission();
+        UI.Output(mission.Description);
+
+        int missionCount = MissionCountFromUI();
+        CommentOnMissionCount(missionCount);
+
+        AttemptMission(missionCount);
+    }
+
+    /// <summary>
+    /// Choose a mission.
+    /// </summary>
+    /// <returns>Mission chosen.</returns>
+    private Mission ChooseMission()
+    {
+        IList<Mission> missions = AllMissions;
+        string[] missionNames = missions.Select(a => a.Name).ToArray();
+        int index = UI.Choose(ChooseMissionMessage, missionNames);
+        return missions[index];
+    }
+
+    /// <summary>
+    /// Message to display when choosing a mission.
+    /// </summary>
+    protected abstract string ChooseMissionMessage { get; }
+
+    /// <summary>
+    /// All aviailable missions to choose from.
+    /// </summary>
+    protected abstract IList<Mission> AllMissions { get; }
+
+    /// <summary>
+    /// Get mission count from UI. If mission count exceeds a reasonable maximum, ask UI again.
+    /// </summary>
+    /// <returns>Mission count from UI.</returns>
+    private int MissionCountFromUI()
+    {
+        const string HowManyMissions = "HOW MANY MISSIONS HAVE YOU FLOWN?";
+        string inputMessage = HowManyMissions;
+
+        bool resultIsValid;
+        int result;
+        do
+        {
+            UI.Output(inputMessage);
+            result = UI.InputInteger();
+            if (result < 0)
+            {
+                UI.Output($"NUMBER OF MISSIONS CAN'T BE NEGATIVE.");
+                resultIsValid = false;
+            }
+            else if (result > MaxMissionCount)
+            {
+                resultIsValid = false;
+                UI.Output($"MISSIONS, NOT MILES...{MaxMissionCount} MISSIONS IS HIGH EVEN FOR OLD-TIMERS.");
+                inputMessage = "NOW THEN, " + HowManyMissions;
+            }
+            else
+            {
+                resultIsValid = true;
+            }
+        }
+        while (!resultIsValid);
+
+        return result;
+    }
+
+    /// <summary>
+    /// Display a message about the given mission count, if it is unusually high or low.
+    /// </summary>
+    /// <param name="missionCount">Mission count to comment on.</param>
+    private void CommentOnMissionCount(int missionCount)
+    {
+        if (missionCount >= 100)
+        {
+            UI.Output("THAT'S PUSHING THE ODDS!");
+        }
+        else if (missionCount < 25)
+        {
+            UI.Output("FRESH OUT OF TRAINING, EH?");
+        }
+    }
+
+    /// <summary>
+    /// Attempt mission.
+    /// </summary>
+    /// <param name="missionCount">Number of missions previously flown. Higher mission counts will yield a higher probability of success.</param>
+    private void AttemptMission(int missionCount)
+    {
+        if (missionCount < RandomInteger(0, MaxMissionCount))
+        {
+            MissedTarget();
+        }
+        else
+        {
+            MissionSucceeded();
+        }
+    }
+
+    /// <summary>
+    /// Display message indicating that target was missed. Choose enemy artillery and perform a counterattack.
+    /// </summary>
+    private void MissedTarget()
+    {
+        UI.Output("MISSED TARGET BY " + (2 + RandomInteger(0, 30)) + " MILES!");
+        UI.Output("NOW YOU'RE REALLY IN FOR IT !!");
+
+        // Choose enemy and counterattack.
+        EnemyArtillery enemyArtillery = ChooseEnemyArtillery();
+
+        if (enemyArtillery == Missiles)
+        {
+            EnemyCounterattack(enemyArtillery, hitRatePercent: 0);
+        }
+        else
+        {
+            int hitRatePercent = EnemyHitRatePercentFromUI();
+            if (hitRatePercent < MinEnemyHitRatePercent)
+            {
+                UI.Output("YOU LIE, BUT YOU'LL PAY...");
+                MissionFailed();
+            }
+            else
+            {
+                EnemyCounterattack(enemyArtillery, hitRatePercent);
+            }
+        }
+    }
+
+    /// <summary>
+    /// Choose enemy artillery from UI.
+    /// </summary>
+    /// <returns>Artillery chosen.</returns>
+    private EnemyArtillery ChooseEnemyArtillery()
+    {
+        EnemyArtillery[] artilleries = new EnemyArtillery[] { Guns, Missiles, Both };
+        string[] artilleryNames = artilleries.Select(a => a.Name).ToArray();
+        int index = UI.Choose("DOES THE ENEMY HAVE", artilleryNames);
+        return artilleries[index];
+    }
+
+    /// <summary>
+    /// Minimum allowed hit rate percent.
+    /// </summary>
+    private const int MinEnemyHitRatePercent = 10;
+
+    /// <summary>
+    /// Maximum allowed hit rate percent.
+    /// </summary>
+    private const int MaxEnemyHitRatePercent = 50;
+
+    /// <summary>
+    /// Get the enemy hit rate percent from UI. Value must be between zero and <see cref="MaxEnemyHitRatePercent"/>.
+    /// If value is less than <see cref="MinEnemyHitRatePercent"/>, mission fails automatically because the user is
+    /// assumed to be untruthful.
+    /// </summary>
+    /// <returns>Enemy hit rate percent from UI.</returns>
+    private int EnemyHitRatePercentFromUI()
+    {
+        UI.Output($"WHAT'S THE PERCENT HIT RATE OF ENEMY GUNNERS ({MinEnemyHitRatePercent} TO {MaxEnemyHitRatePercent})");
+
+        bool resultIsValid;
+        int result;
+        do
+        {
+            result = UI.InputInteger();
+            // Let them enter a number below the stated minimum, as they will be caught and punished.
+            if (0 <= result && result <= MaxEnemyHitRatePercent)
+            {
+                resultIsValid = true;
+            }
+            else
+            {
+                resultIsValid = false;
+                UI.Output($"NUMBER MUST BE FROM {MinEnemyHitRatePercent} TO {MaxEnemyHitRatePercent}");
+            }
+        }
+        while (!resultIsValid);
+
+        return result;
+    }
+}

12_Bombs_Away/csharp/BombsAwayGame/Side.cs

@@ -0,0 +1,97 @@
+namespace BombsAwayGame;
+
+/// <summary>
+/// Represents a protagonist in the game.
+/// </summary>
+internal abstract class Side
+{
+    /// <summary>
+    /// Create instance using the given UI.
+    /// </summary>
+    /// <param name="ui">UI to use.</param>
+    public Side(IUserInterface ui)
+    {
+        UI = ui;
+    }
+
+    /// <summary>
+    /// Play this side.
+    /// </summary>
+    public abstract void Play();
+
+    /// <summary>
+    /// User interface supplied to ctor.
+    /// </summary>
+    protected IUserInterface UI { get; }
+
+    /// <summary>
+    /// Random-number generator for this play-through.
+    /// </summary>
+    private readonly Random _random = new();
+
+    /// <summary>
+    /// Gets a random floating-point number greater than or equal to zero, and less than one.
+    /// </summary>
+    /// <returns>Random floating-point number greater than or equal to zero, and less than one.</returns>
+    protected double RandomFrac() => _random.NextDouble();
+
+    /// <summary>
+    /// Gets a random integer in a range.
+    /// </summary>
+    /// <param name="minValue">The inclusive lower bound of the number returned.</param>
+    /// <param name="maxValue">The exclusive upper bound of the number returned.</param>
+    /// <returns>Random integer in a range.</returns>
+    protected int RandomInteger(int minValue, int maxValue) => _random.Next(minValue: minValue, maxValue: maxValue);
+
+    /// <summary>
+    /// Display messages indicating the mission succeeded.
+    /// </summary>
+    protected void MissionSucceeded()
+    {
+        UI.Output("DIRECT HIT!!!! " + RandomInteger(0, 100) + " KILLED.");
+        UI.Output("MISSION SUCCESSFUL.");
+    }
+
+    /// <summary>
+    /// Gets the Guns type of enemy artillery.
+    /// </summary>
+    protected EnemyArtillery Guns { get; } = new("GUNS", 0);
+
+    /// <summary>
+    /// Gets the Missiles type of enemy artillery.
+    /// </summary>
+    protected EnemyArtillery Missiles { get; } = new("MISSILES", 35);
+
+    /// <summary>
+    /// Gets the Both Guns and Missiles type of enemy artillery.
+    /// </summary>
+    protected EnemyArtillery Both { get; } = new("BOTH", 35);
+
+    /// <summary>
+    /// Perform enemy counterattack using the given artillery and hit rate percent.
+    /// </summary>
+    /// <param name="artillery">Enemy artillery to use.</param>
+    /// <param name="hitRatePercent">Hit rate percent for enemy.</param>
+    protected void EnemyCounterattack(EnemyArtillery artillery, int hitRatePercent)
+    {
+        if (hitRatePercent + artillery.Accuracy > RandomInteger(0, 100))
+        {
+            MissionFailed();
+        }
+        else
+        {
+            UI.Output("YOU MADE IT THROUGH TREMENDOUS FLAK!!");
+        }
+    }
+
+    /// <summary>
+    /// Display messages indicating the mission failed.
+    /// </summary>
+    protected void MissionFailed()
+    {
+        UI.Output("* * * * BOOM * * * *");
+        UI.Output("YOU HAVE BEEN SHOT DOWN.....");
+        UI.Output("DEARLY BELOVED, WE ARE GATHERED HERE TODAY TO PAY OUR");
+        UI.Output("LAST TRIBUTE...");
+    }
+}