using DominionBase.Utilities;
using System;
using System.Diagnostics.Contracts;
using System.Linq;
using System.Reflection;
using System.Xml;

namespace DominionBase.Players.AI
{
	public class RandomAI : Player, IComputerAI
	{
		public static string AIName => "Random";
		public static string AIDescription => "Randomly chooses one of the other AIs to play as.";

		private Basic ActualPlayer = null;

		public string AIType
		{
			get
			{
				var myType = Phase == PhaseEnum.Endgame ? ActualPlayer.GetType() : GetType();

				return (string)myType.GetProperty("AIName", BindingFlags.Static | BindingFlags.Public | BindingFlags.GetProperty | BindingFlags.FlattenHierarchy).GetValue(null, null);
			}
		}

		public RandomAI(Game game, string name)
			: base(game, name)
		{
			_PlayerType = PlayerType.Computer;

			var aiTypes = Assembly.GetExecutingAssembly().GetTypes().Where(x =>
				(x == typeof(Basic) || x.IsSubclassOf(typeof(Basic))) &&
				game.Settings.RandomAI_AllowedAIs.Contains(x.FullName) &&
				(!game.Settings.RandomAI_Unique || !game.Players.Any(p =>
					p.GetType() == x || (p.GetType() == typeof(RandomAI) && ((RandomAI)p).ActualPlayer.GetType() == x)))).ToList();

			if (!aiTypes.Any())
				throw new GameCreationException(
						$"Cannot find a fitting AI to choose for Random!{Environment.NewLine}Please check your game settings and verify that there are enough AIs to choose from");

			var aiType = aiTypes.Choose();
			ActualPlayer = (Basic)Activator.CreateInstance(aiType, game, name + " (R)", this);
		}

		public AIState State => ActualPlayer.State;

		public override void StartAsync()
		{
			ActualPlayer.StartAsync();
			base.StartAsync();
		}

		public override void Setup(IGame game)
		{
			base.Setup(game);

			ActualPlayer.Setup(game, this);
		}

		public override void Clear()
		{
			ActualPlayer.Clear();
			base.Clear();
		}

		public override void TearDown(IGame game)
		{
			ActualPlayer.TearDown(game);
			base.TearDown(game);
		}

		public override XmlNode GenerateXml(XmlDocument doc)
		{
			Contract.Requires(doc != null, "doc cannot be null");
			var xnBase = base.GenerateXml(doc);

			var xe = doc.CreateElement("random_type");
			xe.InnerText = ActualPlayer.GetType().ToString();
			xnBase.AppendChild(xe);

			return xnBase;
		}

		internal override void Load(XmlNode xnPlayer)
		{
			base.Load(xnPlayer);

			var xnRandomType = xnPlayer.SelectSingleNode("random_type");
			if (xnRandomType == null)
				return;

			var randomType = Type.GetType(xnRandomType.InnerText);
			ActualPlayer = (Basic)Activator.CreateInstance(randomType, _Game, Name + " (R)", this);
		}
	}
}