namespace OpenTraffic.Model.Simulator.RouteAssigner
{
    using System;
    using System.Collections.Generic;
    using System.Text;
    using OpenTraffic.Model.Route;

    [Serializable]

    public class Logit : ProbabilityRouteAssigner
    {
        private float factor = -1;
        private bool normalize = true;

        public Logit(float factor, bool normalize)
        {
            this.factor = factor;
            this.normalize = normalize;
        }

        public override Object Clone()
        {
            return new Logit(factor, normalize);
        }

        protected override double GetGains(Vehicle v, Dictionary<TrafficRoute, Double> gains)
        {
            double totGain = 0;

            if (v != null && gains != null)
            {
                List<RouteContainer> routes = RoutesLookup[v.Origin][v.Destination];
                gains.Clear();
                double factor1 = this.factor;
                double minCost = float.PositiveInfinity;
                Dictionary<TrafficRoute, double> tgains = new Dictionary<TrafficRoute, double>();
                for (int i = 0; i < routes.Count; i++)
                {
                    foreach (TrafficRoute r in routes[i].Routes)
                    {
                        if (r != null)
                        {
                            double cost = v.routeClass.CalculateCost(r, inResult, v.StartTime);
                            tgains.Add(r, cost);
                            minCost = Math.Min(minCost, cost);
                        }
                    }
                }
                if (normalize) factor1 = factor1 / minCost;

                foreach (KeyValuePair<TrafficRoute, Double> kv in tgains)
                {
                    double utility = factor1 * kv.Value;
                    if (utility != 0)
                    {
                        double gain = Math.Exp(utility);
                        if (gain > 0) // The same as gain!=0 because of gain is never negative.
                        {
                            totGain += gain;
                            gains.Add(kv.Key, gain);
                        }
                    }
                }
            }

            return totGain;
        }

        public override string ToString()
        {
            return "Logit(" + this.factor + ", " + this.normalize + ")";
        }

    }
}