Clumsy C# solution to advent of code day 22

advent-of-code-day-22.cs

// n.b. Linqpad script


class QueueSpellChooser : ISpellChooser
{
	private Queue<Spell> spellQueue;
	public QueueSpellChooser(IEnumerable<Spell> spells)
	{
		spellQueue = new Queue<Spell>(spells);
    }
	public Spell GetNextSpell(PlayerStatus status)
	{
		return spellQueue.Dequeue();
	}
	public void WinningAmount(int amount)
	{
	}
	public void NewBattle()
	{
	}
}

interface ISpellChooser
{
	void NewBattle();
	Spell GetNextSpell(PlayerStatus status);
	void WinningAmount(int amount);
}

class SpellChooser : ISpellChooser
{
	public int bestWinningAmount = Int32.MaxValue;
	public List<string> choices = new List<string>();
	private Random rand = new Random();
	public Spell GetNextSpell(PlayerStatus status)
	{
		var options = spells.Where(s => s.Cost <= status.Mana && 
			s.Cost + status.ManaSpent < bestWinningAmount &&
			!status.IsSpellActive(s.Name)).ToList();
		if (options.Count == 0) return null;
		
		var t = options[rand.Next(options.Count)].GetType();
		
		var spell = (Spell)Activator.CreateInstance(t);
		choices.Add(spell.Name);
		return spell;
	}
	public void NewBattle()
	{
		choices.Clear();
	}
	public void WinningAmount(int amount)
	{
		if (amount < bestWinningAmount)
		{
			Console.WriteLine("NEW BEST AMOUNT {0}", amount);
			foreach(var choice in choices)
				Console.WriteLine(choice);
			bestWinningAmount = amount;
		}
	}
}


abstract class Spell
{
	public Spell(string name, int cost)
	{
		Name = name;
		Cost = cost;
	}
	public int Cost { get; }
	public string Name { get; }
	public abstract void Use(PlayerStatus self, PlayerStatus opponent, bool debug);
	public abstract int Timer { get; }
}

class MagicMissile : Spell
{
	public MagicMissile() : base("Magic Missile", 53) { }
	public override void Use(PlayerStatus self, PlayerStatus opponent, bool debug)
	{
		if (debug) Console.WriteLine("Magic Missile deals 4 damage");
		opponent.AddHitPoints(-4);
	}
	public override int Timer { get { return 0; } }
}

class Drain : Spell
{
	public Drain() : base("Drain", 73) { }
	public override void Use(PlayerStatus self, PlayerStatus opponent, bool debug)
	{
		if (debug) Console.WriteLine ("Player casts Drain, dealing 2 damage, and healing 2 hit points");
		self.AddHitPoints(2);
		opponent.AddHitPoints(-2);
	}
	public override int Timer { get { return 0; } }
}

class Shield : Spell
{
	public Shield() : base("Shield", 113) { }
	private int timer = 6;
	public override void Use(PlayerStatus self, PlayerStatus opponent, bool debug)
	{
		if (timer == 6)
		{
			if (debug) Console.WriteLine("Shield increases armor by 7");
			self.AddArmor(7);
		}
		if (timer == 1)
		{
			if (debug) Console.WriteLine("Shield wears off, decreasing armor by 7");
			self.AddArmor(-7);
		}
		timer--;
	}
	public override int Timer { get { return timer; } }
}

class Poison : Spell
{
	public Poison() : base("Poison", 173) { }
	private int timer = 6;
	public override void Use(PlayerStatus self, PlayerStatus opponent, bool debug)
	{		
		if (debug) Console.WriteLine("Poison deals 3 damage");
		opponent.AddHitPoints(-3);
		timer--;
	}
	public override int Timer { get { return timer; } }
}

class Recharge : Spell
{
	public Recharge() : base("Recharge", 229) { }
	private int timer = 5;
	public override void Use(PlayerStatus self, PlayerStatus opponent, bool debug = true)
	{
		if (debug) Console.WriteLine("Recharge increases mana by 101");
		self.AddMana(101);
		timer--;
	}
	public override int Timer { get { return timer; } }
}

static List<Spell> spells = new List<Spell>()
{
	new MagicMissile(),
	new Drain(),
	new Shield(),
	new Recharge(),
	new Poison(),
};

bool Battle(PlayerStatus player, PlayerStatus boss, ISpellChooser spellChooser, bool hard, bool debug = false)
{
	spellChooser.NewBattle();
	while (player.HitPoints > 0 && boss.HitPoints > 0)
	{
		if (debug)
		{
			Console.WriteLine("-- Player turn --");
			Console.WriteLine($"Player has {player.HitPoints} hit points, {player.Armor} armor, {player.Mana} mana");
			Console.WriteLine($"Boss has {boss.HitPoints} hit points");
		}
		if (hard)
		{
			player.AddHitPoints(-1);
			if (player.HitPoints <= 0) return false;
		}
		player.UseSpells(boss, debug);
		var spell = spellChooser.GetNextSpell(player);
		// can't afford any more spells (or this battle won't be cheapest)
		if (spell == null) return false;

		if (debug) Console.WriteLine($"Player casts {spell.Name}");
		player.AddSpell(spell, boss, debug);
	
		if (debug)
		{
			Console.WriteLine("-- Boss turn --");
			Console.WriteLine($"Player has {player.HitPoints} hit points, {player.Armor} armor, {player.Mana} mana");
			Console.WriteLine($"Boss has {boss.HitPoints} hit points");
		}
		player.UseSpells(boss, debug);
		if (boss.HitPoints > 0)	player.HitBy(boss, debug);
	}
	
	var playerWins = player.HitPoints > 0;
	if (playerWins) spellChooser.WinningAmount(player.ManaSpent);
	return playerWins;
}

class PlayerStatus
{
	private List<Spell> activeSpells = new List<Spell>();
	public PlayerStatus(int hp, int d, int a, int m)
	{
		HitPoints = hp;
		Damage = d;
		Armor = a;
		Mana = m;
	}
	public int HitPoints { get; private set; }
	public int Damage { get; private set; }
	public int Armor { get; private set; }
	public int Mana { get; private set; }
	public int ManaSpent { get; private set; }

	public void AddHitPoints(int hitPoints)
	{
		HitPoints += hitPoints;
	}

	public void AddArmor(int armor)
	{
		Armor += armor;
	}

	public void AddMana(int mana)
	{
		Mana += mana;
	}

	public void AddSpell(Spell spell, PlayerStatus opponent, bool debug = false)
	{		
		Mana -= spell.Cost;
		ManaSpent += spell.Cost;
		if (Mana < 0) throw new ArgumentException("Can't afford this spell");
		if (spell.Timer == 0)
		{
			spell.Use(this, opponent, debug);
		}
		else
		{
			activeSpells.Add(spell);
		}
	}

	public void UseSpells(PlayerStatus boss, bool debug = false)
	{
		foreach (var spell in activeSpells)
		{
			if (boss.HitPoints > 0)
			{
				spell.Use(this, boss, debug);
				if (debug)
					Console.WriteLine($"{spell.Name}'s timer is now {spell.Timer}");
			}
		}
		activeSpells.RemoveAll(s => s.Timer == 0);
	}

	public void HitBy(PlayerStatus boss, bool debug = false)
	{
		var bossDamage = Math.Max(1, boss.Damage - Armor); 
		if (debug) Console.WriteLine($"Boss attacks for {bossDamage} damage");
		HitPoints -= bossDamage;
	}

	public bool IsSpellActive(string spellName)
	{
		return activeSpells.Any(s => s.Name == spellName);
	}
}

void Main()
{
	var testPlayer = new PlayerStatus(10, 0, 0, 250);
	var testBoss = new PlayerStatus(13, 8, 0, 0);
	var spells = new Spell[] { new Poison(), new MagicMissile() };
	//Battle(testPlayer, testBoss, new QueueSpellChooser(spells), true).Dump();

	var testPlayer2 = new PlayerStatus(10, 0, 0, 250);
	var testBoss2 = new PlayerStatus(14, 8, 0, 0);
	var spells2 = new Spell[] { new Recharge(), new Shield(), new Drain(), new Poison(), new MagicMissile() };
	//Battle(testPlayer2, testBoss2, new QueueSpellChooser(spells2), true).Dump();

	var chooser = new SpellChooser();
	for (int n = 0; n < 10000; n++)
	{
		var player = new PlayerStatus(50, 0, 0, 500);
		var boss = new PlayerStatus(58, 9, 0, 500);
		Battle(player, boss, chooser, true, false);
	}
}