using DominionBase.Enums;
using DominionBase.Players;
using System.Diagnostics.Contracts;

namespace DominionBase.Cards.Nocturne
{
	public class Envious : State
	{
		private PhaseChangingEventHandler _phaseChangingEventHandler = null;
		private TurnEndedEventHandler _turnEndedEventHandler;
		private CardPlayedEventHandler _cardPlayedEventHandler = null;

		public Envious()
			: base(Source.Nocturne, Traits.None)
		{
		}

		public override void TakenBy(IPlayer player)
		{
			Contract.Requires(player != null, "player cannot be null");
			base.TakenBy(player);

			_phaseChangingEventHandler = new PhaseChangingEventHandler(Player_PhaseChanging);
			player.PhaseChanging += _phaseChangingEventHandler;
		}

		public override void ReturnedBy(IPlayer player)
		{
			Contract.Requires(player != null, "player cannot be null");
			base.ReturnedBy(player);

			if (_phaseChangingEventHandler != null)
				player.PhaseChanging -= _phaseChangingEventHandler;
		}

		private void Player_PhaseChanging(object sender, PhaseChangingEventArgs e)
		{
			var player = sender as IPlayer;
			if (e.NewPhase != PhaseEnum.BuyTreasure || e.HandledBy.Contains(TypeClass.Envious))
				return;

			e.Resolvers[TypeClass.Envious] = new PhaseChangingResolver(this, "Resolve Envious", Player_SetupSilverGoldRestrictions, true);
		}

		internal void Player_SetupSilverGoldRestrictions(IPlayer player, ref PhaseChangingEventArgs e)
		{
			player.Return(Type);

			_cardPlayedEventHandler = new CardPlayedEventHandler(Player_CardPlayed);
			player.CardPlayed += _cardPlayedEventHandler;

			if (_turnEndedEventHandler != null)
				player.TurnEnded -= _turnEndedEventHandler;

			_turnEndedEventHandler = new TurnEndedEventHandler(Player_TurnEnded);
			player.TurnEnded += _turnEndedEventHandler;

			e.HandledBy.Add(TypeClass.Envious);
		}

		public override void TearDown(IGame game)
		{
			Contract.Requires(game != null, "game cannot be null");
			if (_cardPlayedEventHandler != null)
				foreach (var player in game.Players)
					player.CardPlayed -= _cardPlayedEventHandler;
			_cardPlayedEventHandler = null;

			if (_phaseChangingEventHandler != null)
				foreach (var player in game.Players)
					player.PhaseChanging -= _phaseChangingEventHandler;
			_phaseChangingEventHandler = null;

			if (_turnEndedEventHandler != null)
				foreach (var player in game.Players)
					player.TurnEnded -= _turnEndedEventHandler;
			_turnEndedEventHandler = null;

			base.TearDown(game);
		}

		private void Player_CardPlayed(object sender, CardPlayedEventArgs e)
		{
			// Not quite the same as "Silver and Gold make 1 coin this turn", but it should be accurate enough
			// (Famous last words)
			// TODO -- this should be converted to use BenefitReceiving event instead of CardPlayed
			var negativeCost = 0;
			foreach (var card in e.Cards)
			{
				if (card is Universal.Silver)
					negativeCost -= 1;
				else if (card is Universal.Gold)
					negativeCost -= 2;
			}
			e.Player.ReceiveBenefit(this, new CardBenefit { Currency = new Currency(negativeCost) });
		}

		private void Player_TurnEnded(object sender, TurnEndedEventArgs e)
		{
			var player = sender as IPlayer;

			if (_cardPlayedEventHandler != null)
				player.CardPlayed -= _cardPlayedEventHandler;
			_cardPlayedEventHandler = null;

			if (_phaseChangingEventHandler != null)
				player.PhaseChanging -= _phaseChangingEventHandler;
			_phaseChangingEventHandler = null;

			if (_turnEndedEventHandler != null)
				player.TurnEnded -= _turnEndedEventHandler;
			_turnEndedEventHandler = null;
		}
	}
}