// This file (UnitRequiresAtLeastNUnitsRequirement.cs) is a part of the IBBoard.WarFoundry.API project and is copyright 2011 IBBoard
// 
// The file and the library/program it is in are licensed and distributed, without warranty, under the GNU Affero GPL license, either version 3 of the License or (at your option) any later version. Please see COPYING for more information and the full license.
using System;
using System.Collections.Generic;
using IBBoard.WarFoundry.API.Objects;

namespace IBBoard.WarFoundry.API.Objects.Requirement
{
	/// <summary>
	/// A requirement where a UnitType requires at least N units of one or more unit types before any number of that object can be taken in an army.
	/// </summary>
	public class UnitRequiresAtLeastNUnitsRequirement : RequiresAtLeastNUnitsRequirement
	{
		private UnitType requirementOnType;

		public UnitRequiresAtLeastNUnitsRequirement(UnitType requirementOn) : base()
		{
			requirementOnType = requirementOn;
			FailureStringPrefix = "Army contains " + requirementOn.Name + " and so must contain: ";
		}

		protected override bool IsApplicable(WarFoundryObject toObjectAdded)
		{
			return base.IsApplicable(toObjectAdded) || IsRequirementOnType(toObjectAdded);
		}

		private bool IsRequirementOnType(WarFoundryObject toObjectAdded)
		{
			return requirementOnType.Equals(toObjectAdded) || (toObjectAdded is Unit && requirementOnType.Equals(((Unit)toObjectAdded).UnitType));
		}

		protected override bool IsApplicable(Army toArmy)
		{
			return toArmy.GetUnitTypeCount(requirementOnType) > 0;
		}

		public override Validation ValidatesArmy(Army toArmy)
		{
			return IsApplicable(toArmy) ? base.ValidatesArmy(toArmy) : Validation.NotApplicable;
		}
	}
}