using Deltares.Mathematics;
using Deltares.Standard;

namespace Deltares.Stability.Calculation2
{
    public class LevenbergMarquardtSingleCircleCalculation : SlidingCurvesProcessor, IExtremeCalculation
    {
        private SlipCircleGrid calculationgrid;
        private LevenbergMarquardtExtreme levenbergMarquardtExtreme = new LevenbergMarquardtExtreme();
        private SlidingCircle minimumSlidingCurve;
        private SlipCircleTangentLine slipCircleTangentLine;

        public LevenbergMarquardtSingleCircleCalculation(SlipCircle slipCircle)
        {
            calculationgrid = slipCircle.SlipCircleGrid;
            slipCircleTangentLine = slipCircle.SlipCircleTangentLine;
        }

        public override void Initialize(StabilityModel stabilityModel)
        {
            base.Initialize(stabilityModel);
            levenbergMarquardtExtreme.LevenbergMarquardtOptions = stabilityModel.LevenbergMarquardtOptions;

            levenbergMarquardtExtreme.ParameterCount = 3;
            levenbergMarquardtExtreme.VariableCount = 3;

            // Set the bounds for the Levenberg Marquardt; the radius is composed of middle point and tanggeent line
            levenbergMarquardtExtreme.Parameters[0] = (calculationgrid.GridXLeft + calculationgrid.GridXRight)/2;
            levenbergMarquardtExtreme.Parameters[1] = (calculationgrid.GridZBottom + calculationgrid.GridZTop)/2;
            levenbergMarquardtExtreme.Parameters[2] = (slipCircleTangentLine.TangentLineZBottom + slipCircleTangentLine.TangentLineZTop)/2;

            // Communicate the address of the calculation
            levenbergMarquardtExtreme.LevenbergMarquardtCalculation = this;
        }

        public override SlidingCurve Calculate()
        {
            minimumSlidingCurve = null;

            // Determine safety factor
            levenbergMarquardtExtreme.Calculation();

            return minimumSlidingCurve;
        }

        public double ComputeExtremeResult(double[] AParameters)
        {
            var slidingCircle = new SlidingCircle();
            slidingCircle.Center = new Point2D(AParameters[0], AParameters[1]);
            slidingCircle.Radius = AParameters[1] - AParameters[2];

            // Calculation
            double stabilityFactor = GetSafetyFactor(slidingCircle);

            if (minimumSlidingCurve == null || stabilityFactor < minimumSlidingCurve.SafetyFactor)
            {
                minimumSlidingCurve = slidingCircle;
            }

            return stabilityFactor;
        }
    }
}