using System;

namespace aima.search.framework
{
	/// <summary>
	/// Ported to .NET by Kris Noesgaard
	/// from the Java implementation by Ravi Mohan
	/// </summary>
	public class Problem 
	{

		Object initialState;

		SuccessorFunction successorFunction;

		GoalTest goalTest;

		StepCostFunction stepCostFunction;

		HeuristicFunction heuristicFunction;

		public Problem(Object initialState, SuccessorFunction successorFunction,
			GoalTest goalTest) 
		{

			this.initialState = initialState;
			this.successorFunction = successorFunction;
			this.goalTest = goalTest;
			this.stepCostFunction = new DefaultStepCostFunction();
			this.heuristicFunction = new DefaultHeuristicFunction();

		}

		public Problem(Object initialState, SuccessorFunction successorFunction,
			GoalTest goalTest, StepCostFunction stepCostFunction) : this(initialState, successorFunction, goalTest)
		{
			
			this.stepCostFunction = stepCostFunction;
		}

		public Problem(Object initialState, SuccessorFunction successorFunction,
			GoalTest goalTest, HeuristicFunction heuristicFunction) : this(initialState, successorFunction, goalTest)
		{
			
			this.heuristicFunction = heuristicFunction;
		}

		public Problem(Object initialState, SuccessorFunction successorFunction,
			GoalTest goalTest, StepCostFunction stepCostFunction,
			HeuristicFunction heuristicFunction) : this(initialState, successorFunction, goalTest, stepCostFunction)
		{
			
			this.heuristicFunction = heuristicFunction;
		}

		public Object getInitialState() 
		{

			return initialState;
		}

		public bool isGoalState(Object state) 
		{

			return goalTest.isGoalState(state);
		}

		public StepCostFunction getStepCostFunction() 
		{
			return stepCostFunction;
		}

		public SuccessorFunction getSuccessorFunction() 
		{
			return successorFunction;
		}

		public HeuristicFunction getHeuristicFunction() 
		{
			// TODO Auto-generated method stub
			return heuristicFunction;
		}

	}
}