using System;
using System.Collections.Generic;
using System.Diagnostics.Contracts;
using System.Linq;

namespace DominionBase.Cards
{
	public abstract class CardLabel
	{
		public virtual string Name { get; private set; }
		public virtual ICard AttachedCard { get; private set; }

		public CardLabel(ICard attachedCard)
		{
			AttachedCard = attachedCard;
		}
	}

	public class CardLabelCollection : List<CardLabel>
	{
		public delegate void CardLabelsChangedEventHandler(object sender, CardLabelsChangedEventArgs e);
		public event CardLabelsChangedEventHandler CardLabelsChanged;

		public CardLabelCollection() { }
		public CardLabelCollection(int capacity) : base(capacity) { }
		public CardLabelCollection(IEnumerable<CardLabel> collection) : base(collection) { }

		public new void Add(CardLabel cardLabel)
		{
			Contract.Requires(cardLabel != null, "cardLabel cannot be null");
			base.Add(cardLabel);

			CardLabelsChanged?.Invoke(this, new CardLabelsChangedEventArgs(this, CardLabelsChangedEventArgs.Operation.Added, cardLabel));
		}

		public new void Remove(CardLabel cardLabel)
		{
			Contract.Requires(cardLabel != null, "cardLabel cannot be null");
			base.Remove(cardLabel);

			CardLabelsChanged?.Invoke(this, new CardLabelsChangedEventArgs(this, CardLabelsChangedEventArgs.Operation.Removed, cardLabel));
		}

		public void RemoveMatching(Type cardLabelType)
		{
			Contract.Requires(cardLabelType != null, "cardLabelType cannot be null");
			var matching = this.Where(c => c.GetType() == cardLabelType);
			if (matching.Any())
			{
				RemoveAll(c => matching.Contains(c));

				CardLabelsChanged?.Invoke(this, new CardLabelsChangedEventArgs(this, CardLabelsChangedEventArgs.Operation.Removed, matching));
			}
		}
	}

	public class CardLabelsChangedEventArgs : EventArgs
	{
		public enum Operation
		{
			Reset,
			Added,
			Removed
		}
		public CardLabelCollection AddedLabels { get; } = new CardLabelCollection();
		public CardLabelCollection RemovedLabels { get; } = new CardLabelCollection();
		public Operation OperationPerformed { get; }
		public CardLabelCollection CardLabels { get; }
		public IPlayer Player { get; }
		public int Count => CardLabels.Count;

		public CardLabelsChangedEventArgs(CardLabelCollection cardLabels, Operation operation)
		{
			CardLabels = cardLabels;
			OperationPerformed = operation;
		}
		public CardLabelsChangedEventArgs(CardLabelCollection cardLabels, Operation operation, CardLabel labelChanged)
			: this(cardLabels, null, operation, labelChanged)
		{
		}
		public CardLabelsChangedEventArgs(CardLabelCollection cardLabels, Operation operation, IEnumerable<CardLabel> labelsChanged)
			: this(cardLabels, null, operation, labelsChanged)
		{
		}
		public CardLabelsChangedEventArgs(CardLabelCollection cardLabels, IPlayer player, Operation operation)
			: this(cardLabels, operation)
		{
			Player = player;
		}
		public CardLabelsChangedEventArgs(CardLabelCollection cardLabels, IPlayer player, Operation operation, CardLabel labelChanged)
			: this(cardLabels, player, operation)
		{
			switch (operation)
			{
				case Operation.Added:
					AddedLabels.Add(labelChanged);
					break;
				case Operation.Removed:
					RemovedLabels.Add(labelChanged);
					break;
			}
		}
		public CardLabelsChangedEventArgs(CardLabelCollection cardLabels, IPlayer player, Operation operation, IEnumerable<CardLabel> labelsChanged)
			: this(cardLabels, player, operation)
		{
			switch (operation)
			{
				case Operation.Added:
					AddedLabels.AddRange(labelsChanged);
					break;
				case Operation.Removed:
					RemovedLabels.AddRange(labelsChanged);
					break;
			}
		}
	}
}