Code that receives a PlanSetup and change Fields ID based on gantry angle. Also ranks if STATIC fields are complementary or field in fields

BeamIdChanger.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using System.Windows;
using VMS.TPS.Common.Model.API;

namespace FieldIdFromGantry
{
    public class BeamIdChanger
    {
        public PlanSetup Plan { get; set; }
        public IEnumerable<Beam> TreatmentBeams { get; set; }

        public string Log = "";

        public BeamIdChanger(PlanSetup plan)
        {
            Plan = plan;
            TreatmentBeams = plan.Beams.Where(e=>!e.IsSetupField);
        }
        public void ChangeBeamId(Beam beam, string append)
        {
            var lastId = beam.Id;
            var newId = Regex.Match(lastId,@"^(\d+)(\.?)(\d+)?").Value + " " + append;
            try
            {

                beam.Id = newId;
                Log += $"Success changing {lastId} Id to {newId} \n";
            }
            catch (Exception)
            {
                Log += $"Could not change {lastId} Id to {newId} \n";
                throw;
            }
        }
        public void ChangeBeamIdFromGantryAngle(Beam beam)
        {
            var futureId = "G" + beam.ControlPoints.First().GantryAngle.ToString("F0");
            if (beam.ControlPoints.First().GantryAngle != beam.ControlPoints.Last().GantryAngle)
            {
                futureId = "G" + beam.ControlPoints.First().GantryAngle.ToString("F0") + "_" + beam.ControlPoints.Last().GantryAngle.ToString("F0");

            }
            ChangeBeamId(beam, futureId);

        }
        public void ChangeBeamsIdsFromGantryAngles()
        {
            FamilyNaming(TreatmentBeams.Where(e => e.Technique.Id == "STATIC"));
            RegularNaming(TreatmentBeams.Where(e => e.Technique.Id != "STATIC"));

        }
        public void FamilyNaming(IEnumerable<Beam> beams)
        {
            var angleBeams = beams.Select(e => e.ControlPoints.First().GantryAngle).Distinct().ToDictionary(e => e,e => beams.Where(s => s.ControlPoints.First().GantryAngle == e));
            var Fams = angleBeams.Select(e => FiFFamily.CreateFifFamily(e.Value));
            Fams.Select(e => e.MotherBeam).ToList().
                ForEach(s => ChangeBeamId(s, "G" + s.ControlPoints.First().GantryAngle.ToString("F0"))); // MotherBeams
            Fams.SelectMany(e => e.FiFBeams).ToList().
                ForEach(s => ChangeBeamId(s,  "G" + s.ControlPoints.First().GantryAngle.ToString("F0") + " FF")); // Fifs Beams;
            Fams.SelectMany(e => e.NotFiFBeams).ToList().
                ForEach(s => ChangeBeamId(s, "G"+ s.ControlPoints.First().GantryAngle.ToString("F0") + " Comp")); // Lower MU but not Fifs Beams;

        }

        public void RegularNaming(IEnumerable<Beam> beams)
        {
            beams.ToList().ForEach(e => ChangeBeamIdFromGantryAngle(e));
        }

    }
    public class FiFFamily
    {
        public IEnumerable<Beam> FiFBeams { get; set; }
        public Beam MotherBeam { get; set; }

        public IEnumerable<Beam> NotFiFBeams { get; set; }
        public double GantryAngle { get => MotherBeam.ControlPoints.First().GantryAngle; set { } }

        public FiFFamily(IEnumerable<Beam> fiFBeams, Beam motherBeam, IEnumerable<Beam> notFiFBeams)
        {
            FiFBeams = fiFBeams;
            MotherBeam = motherBeam;
            NotFiFBeams = notFiFBeams;
        }
        public static FiFFamily CreateFifFamily(IEnumerable<Beam> beams)
        {
            var highMU = beams.OrderBy(e => e.Meterset.Value).Last(); // Using the hghest MU to predict mother field
            var sameColTableJaw = beams.Where(
                e => e.ControlPoints.First().CollimatorAngle == highMU.ControlPoints.First().CollimatorAngle
                &&
                e.ControlPoints.First().PatientSupportAngle == highMU.ControlPoints.First().PatientSupportAngle
                &&
                e.ControlPoints.First().JawPositions == highMU.ControlPoints.First().JawPositions).Where(x=>x!=highMU);
            var notFif = beams.Except(sameColTableJaw).Where(x => x != highMU);
            return new FiFFamily(sameColTableJaw, highMU,notFif);

        }

        
    }
}