using System;
using System.Collections.Generic;
using System.Text;
using OpenTraffic.Model.Graph;

namespace OpenTraffic.Model.Route
{
    public class RouteFactory
    {
        private TrafficZone lastStart;
        private float lastTime;
        private TrafficModel model;
        private Graph.ShortestPath<LinkNode, TurnEdge> sp;
        Dictionary<int, LinkNode> nodes;
        private Result.ResultData result;
        private List<TurnEdge> turns;
        private LinkNode v0;
        private float randFactor;
        private Random rand;

        private class LinkNode : Vertex
        {
            public LinkNode(int id)
                : base(id, null, 0, 0)
            {
            }
        }

        private class StopZone : LinkNode
        {
            public StopZone(int id)
                : base(id)
            {
            }
        }

        private class StartNode : LinkNode
        {
            public StartNode()
                : base(0)
            {
            }
        }

        private class TurnEdge : GraphEdge<LinkNode>
        {
            public Turning t;
            public TurnEdge(Turning t, LinkNode l1, LinkNode l2)
                : base(t.Id, l1, l2, null)
            {
                this.t = t;

            }
        }
        public RouteFactory(TrafficModel m, Result.ResultData res)
        {
            init(m, res, float.NaN);
        }

        public RouteFactory(TrafficModel m, Result.ResultData res, float randFactor)
        {
            init(m, res, randFactor);
        }

        private void init(TrafficModel m, Result.ResultData res, float randFactor1)
        {
            this.randFactor = randFactor1;
            this.model = m;
            this.result = res;
            sp = new Graph.ShortestPath<LinkNode, TurnEdge>();
            lastStart = null;
            lastTime = float.NaN;

            turns = new List<TurnEdge>();

            rand = new Random(23);

            nodes = new Dictionary<int, LinkNode>();
            int id = 1;
            foreach (TrafficModelLink l in model.TrafficModelLinks)
            {
                LinkNode v = new LinkNode(++id);
                nodes.Add(l.Id, v);
            }

            foreach (TrafficZone z in model.TrafficZones)
            {
                StopZone v = new StopZone(++id);
                nodes.Add(-z.Id, v);
            }

            foreach (TrafficModelLink l in m.TrafficModelLinks)
            {
                foreach (Turning t in l.Turnings)
                {
                    LinkNode te = (t.Destination is TrafficModelConnector) ? nodes[-t.Destination.Target.Id] : nodes[t.Destination.Id];
                    turns.Add(new TurnEdge(t, nodes[t.Origin.Id], te));
                }
            }

        }


        public RouteContainer GetRoute(TrafficZone v1, TrafficZone v2)
        {
            return GetRoute(v1, v2, 0, true, null);
        }

        public RouteContainer GetRoute(TrafficZone startZone, TrafficZone stopZone, float startTime, bool cache)
        {
            return GetRoute(startZone, stopZone, startTime, cache, null);
        }

        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1011:ConsiderPassingBaseTypesAsParameters")]
        public RouteContainer GetRoute(TrafficZone startZone, TrafficZone stopZone, float startTime, bool cache, VehicleClass c)
        {
            if (startZone == stopZone || startZone == null || stopZone == null)
            {
                return null;
            }

            if (lastStart != startZone || lastTime != startTime)
            {
                TrafficProfile.GetProfile().Start("Creating graph");
                Graph.Graph<LinkNode, TurnEdge> graph = new Graph<LinkNode, TurnEdge>();

                foreach (KeyValuePair<int, LinkNode> kv in nodes)
                {
                    graph.Add(kv.Value);
                }
                foreach (TurnEdge t in turns)
                {
                    graph.Add(t);
                }

                v0 = new StartNode();
                graph.Add(v0);

                foreach (TrafficModelLink l in startZone.LinksOut) // This should be connectors
                {
                    foreach (Turning t in l.Turnings)
                    {
                        LinkNode te = (t.Destination is TrafficModelConnector) ? nodes[-t.Destination.Target.Id] : nodes[t.Destination.Id];
                        graph.Add(new TurnEdge(t, v0, te));
                    }
                }

                TrafficProfile.GetProfile().SStart("Djikstra");
                sp.Proceed(graph, v0, null, delegate(TurnEdge te, float cIn, ref float t)
                {
                    TrafficModelLink l = te.t.Origin;
                    TrafficModelLink d = te.t.Destination;
                    float speedfactor = c == null ? 1.0f : c.SpeedFactor;


                    float travelTime = GetLinkTT(t, l, speedfactor, 0.0f);
                    if (d is TrafficModelConnector)
                    {
                        travelTime += GetLinkTT(t, d, speedfactor, te.t.Rate);
                    }


                    t += travelTime;



                    float cost = (c == null) ? cost = travelTime : c.CalculateCost(travelTime, l.Length);


                    if (!float.IsNaN(randFactor))
                    {

                        cost = cost * (1.0f + (float)rand.NextDouble() * randFactor - randFactor / 2.0f);

                    }
                    return cost;
                    //return (float)Math.Max(cost, 0.1);

                }, startTime);
                lastStart = startZone;
                lastTime = startTime;
                TrafficProfile.GetProfile().Stop();

            }
            if (!cache)
            {
                lastStart = null;
                lastTime = -1;
            }

            TrafficProfile.GetProfile().Start("extract");
            List<TurnEdge> lr = sp.ExtractRoute(v0, nodes[-stopZone.Id]);

            TrafficModelLink[] links = new TrafficModelLink[lr.Count - 1];
            TrafficModelLink start = lr[0].t.Origin;
            TrafficModelLink stop = lr[lr.Count - 1].t.Destination;
            for (int i = 0; i < links.Length; i++)
                links[i] = lr[i].t.Destination;

            RouteContainer r = new RouteContainer(-1, start, stop, links);
            // System.Diagnostics.Debug.Assert(r.IsValid());
            TrafficProfile.GetProfile().Stop();
            return r;
        }

        private float GetLinkTT(float t, TrafficModelLink l, float speedfactor, float extraTT)
        {
            float travelTime = 0.0f;

            if (result != null)
            {
                Result.ResultLink rl = result.GetLinkResultFromTime(t, l.Id);
                if (rl != null)
                {
                    travelTime = rl.TravelTime / speedfactor + rl.QueuingTime;
                }
            }
            if (travelTime == 0.0f)
            {
                travelTime = l.CalculateFreeFlowTravelTime() / speedfactor;
                travelTime += extraTT;
            }

            return travelTime;
        }

    }
}