// This file (AbstractRequirement.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;


namespace IBBoard.WarFoundry.API.Objects.Requirement
{
	public abstract class AbstractRequirement : IRequirement
	{
		public abstract string RequirementID { get; }

		public override bool Equals (object obj)
		{
			if (obj == null)
			{
				return false;
			}
			else if (obj.GetType().Equals(this.GetType()))
			{
				return TypeEquals(obj);
			}
			else
			{
				return false;
			}
		}

		public override abstract int GetHashCode();

		/// <summary>
		/// Type-specific equality checking - must be implemented by each class
		/// </summary>
		/// <returns>
		/// <code>true</code> if this object is equal to <code>obj</code>, else <code>false</code>
		/// </returns>
		/// <param name='obj'>
		/// The object to compare to
		/// </param>
		protected abstract bool TypeEquals(object obj);

		protected virtual bool IsApplicable(WarFoundryObject toObjectAdded, Army toArmy)
		{
			return IsApplicable(toArmy) || IsApplicable(toObjectAdded);
		}

		protected virtual bool IsApplicable(Army toArmy)
		{
			return true;
		}

		protected virtual bool IsApplicable(WarFoundryObject toObject)
		{
			return true;
		}


		public string GetValidationMessage(Army army)
		{
			string message = "";

			Validation result = ValidatesArmy(army);
			if (!Validates.AsOkay(result))
			{
				message = GetValidationFailedMessage(army);
			}

			return message;
		}

		protected abstract string GetValidationFailedMessage(Army army);

		public string GetAllowsAddingMessage(UnitType toAdd, Army toArmy)
		{
			string message = "";

			Validation result = AllowsAdding(toAdd, toArmy);
			if (!Validates.AsOkay(result))
			{
				message = GetAllowsAddingFailedMessage(toAdd, toArmy);
			}

			return message;
		}

		protected abstract string GetAllowsAddingFailedMessage(UnitType toAdd, Army toArmy);

		public abstract  Validation AllowsAdding(WarFoundryObject wfObject, Army toArmy);

		public abstract  Validation ValidatesArmy(Army army);
	}
}