using Assets.Common;
using Assets.Map;
using Assets.Voronoi;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using UnityEngine;

namespace Assets.Scripts
{
    public class PointProximityComparer : IEqualityComparer<Point>
    {
        double _threshold;

        public PointProximityComparer(double threshold = 0.2)
        {
            _threshold = threshold;
        }

        public bool Equals(Point x, Point y)
        {
            return Point.Dist(x, y) < _threshold;
        }

        public int GetHashCode(Point obj)
        {
            return obj.GetHashCode();
        }
    }

    public class CityField
    {
        public List<Point> boundary;
    }

    public class City
    {
        public Graph<Voronoi.Site> startGraph;
        public List<Voronoi.Site> sites;

        public Graph<Point> roads = new Graph<Point>();
        public Graph<Point> fieldBoundaries = new Graph<Point>();

        public List<CityField> fields = new List<CityField>();

        public List<(int, int)> edges;
 
        public City(Graph<Site> startGraph)
        {
            this.startGraph = startGraph;

            this.sites = new List<Voronoi.Site>();
            this.edges = new List<(int, int)>();
        }

        public City(Graph<Site> startGraph, List<Site> sitesList) : this(startGraph)
        {
            this.sites = sitesList;
        }

        public void AddSite(Site site)
        {
            sites.Add(site);
            FixBoundaryEdges(site);
        }

        private void FixBoundaryEdges(Site site)
        {
            var a = edges;
            var b = site.Edges.Select(x => x.Item1 < x.Item2 ? x : (x.Item2, x.Item1)); 

            edges = a.Union(b).Except(a.Intersect(b)).ToList();
        }

        public void CreateRoadGraph(IList<Point> points)
        {
            var pointsForRoads = sites.SelectMany(site => site.Vertices.Select(i => (i, points[i])).Append((-1, site.Point))).Distinct().ToList();
            var mapping        = pointsForRoads.Select((x, i) => x.Item1 == -1 ? (-1, -1) : (i, x.Item1)).Where(x => x.Item1 != -1).ToDictionary(x => x.Item2, x => x.Item1);

            VoronoiGenerator generator = new VoronoiGenerator(pointsForRoads.Select(x => x.Item2));
            generator.Generate();

            roads = generator.Delaunay.Morph(s => s.Point);

            fieldBoundaries = new Graph<Point> { Vertices = roads.Vertices, Edges = edges.Select(e => (mapping[e.Item1], mapping[e.Item2])) };
        }
    }

    [Serializable]
    public class GraphGeneratorDebug
    {
        public bool displayVertices = false;
        public bool displayCrossroads = true;
        public bool displayEdges = false;
        public bool displayCities = true;
        public bool displayCityRoads = true;
        public bool displayFieldBoundaries = true;
        public bool displayWorldRoads = false;
    }

    [RequireComponent(typeof(GraphGenerator))]
    public class CityGenerator : MonoBehaviour
    {
        private System.Random _random;
        private Graph<Point> _voronoiGraph;
        private Graph<Location> _locationGraph;
        private Graph<Site> _basicGraph;
        private List<int> verticesForRoads;
        private List<int> verticesForCitites;
        public GraphGeneratorDebug debug;
        public List<City> cities = new List<City>();
        Graph<Site> roads = new Graph<Site>();

        Graph<Point> mainRoads = new Graph<Point>();

        List<int> CountProbablitityOfCity(List<int> vertices)
        {
            List<int> probabilities = new List<int>();
            vertices.ForEach(v => probabilities.Add((v % 2 == 0 ? _random.Next(0, 50) : _random.Next(50, 100))));
            return probabilities;
        }

        List<int> LocateCities()
        {
            //  var verticesForCitites = CountProbablitityOfCity(ChoosePoints(20));
            // verticesForCitites.Sort();
            // return verticesForCitites.GetRange(0, 10);
            return ChoosePoints(20);
        }

        public bool IsPointInsideCity(City city, Point point)
        {
            return city.sites.Any(s => PointUtils.IsPointInside(point, s.Vertices.Select(i => _voronoiGraph[i]).ToArray()));
        }

        City CreateCity(int vertex, int size)
        {
            City newCity = new City(_basicGraph);
            var site = _basicGraph.Vertices[vertex];
            var sites = new List<Site>() { site };
            var location = site.Location;

            for (int i = 0; i < size - 1; i++)
            {
                location = site.Location;
                var neighbours = _basicGraph.Neighbours(site.Index).Select(j => _basicGraph.Vertices[j]).Where(s => s.Location == location).ToList();
                site = neighbours[_random.Next(neighbours.Count)];
                sites.Add(site);
            }

            foreach (var s in sites.Distinct())
            {
                newCity.AddSite(s);
            }

            newCity.CreateRoadGraph(_voronoiGraph.Vertices);

            var edges = newCity.roads.Edges.ToList();
            foreach (var (a, b) in edges)
            {
                var (va, vb) = (newCity.roads[a], newCity.roads[b]);
                var center = (va + vb) / 2;

                if (!IsPointInsideCity(newCity, center))
                    newCity.roads.DeleteEdge(a, b);
            }

            ConnectPointsIntoRoads(newCity);
            CreateFieldBoundaries(newCity);

            return newCity;
        }

        List<int> ChoosePoints(int number)
        {
            var vertices = new List<int>();
            for (int i = 0; i < number; i++)
            {
                var randomLocation = _locationGraph.Vertices[_random.Next(1, _locationGraph.Vertices.Count())];
                var count = randomLocation.Sites.Count();
                Site randomPoint;
                randomPoint = randomLocation.Sites[_random.Next(0, count)];
                vertices.Add(randomPoint.Index);
            }
            return vertices;
        }

        void ConnectPointsIntoRoads(City city)
        {
            var original = city.roads.Morph(s => s, e => Point.Dist(city.roads[e.Item1], city.roads[e.Item2]));

            //1.Sort all the edges in non - decreasing order of their weight.
            //2.Pick the smallest edge.Check if it forms a cycle with the spanning tree formed so far. If cycle is not formed, include this edge.Else, discard it.
            //3.Repeat step#2 until there are (V-1) edges in the spanning tree.

            var edges = original.Edges.OrderByDescending(e => original.GetEdgeData(e));

            Graph<Point> roads = new Graph<Point>() { Vertices = city.roads.Vertices };

            foreach (var edge in original.Edges)
            {
                roads.AddEdge(edge.Item1, edge.Item2);

                if (Graph<Point>.HasCycle(roads))
                    roads.DeleteEdge(edge.Item1, edge.Item2);
                if (roads.Edges.Count() == roads.Vertices.Count() - 1)
                    break;
            }

            city.roads = roads;
        }

        private void CreateFieldBoundaries(City city)
        {
            foreach (var (a, b) in city.roads.Edges)
                city.fieldBoundaries.AddEdge(a, b);
        }

        void CreateWorldRoadGraph()
        {
            roads.Vertices = verticesForCitites.Select(i => _basicGraph.Vertices[i]).ToList();

            VoronoiGenerator generator = new VoronoiGenerator(roads.Vertices.Select(s => s.Point).ToList());
            generator.Generate();

            roads.Edges = generator.Delaunay.Edges;
        }


        void AddLanesToRoads()
        {
            // ergo dodaj randomowe połączenia xd
        }




        // UI Methods


        public void Start()
        {
            Reset();
        }

        public void Reset()
        {

            var graphGenerator = GetComponent<GraphGenerator>();
            _random = new System.Random(graphGenerator.seed);
            cities = new List<City>();
        }

        public void NewCity()
        {
            cities.Add(CreateCity(LocateCities()[_random.Next(0, 10)], _random.Next(0, 10)));
        }

        public void Generate()
        {
            var graphGenerator = GetComponent<GraphGenerator>();
            graphGenerator.Generate();
            _basicGraph = graphGenerator.VoronoiGenerator.Delaunay.Morph(l => l);
            _voronoiGraph = graphGenerator.VoronoiGenerator.Voronoi;
            _locationGraph = graphGenerator.LocationGenerator.Result;

            verticesForCitites = LocateCities();
            foreach (var index in verticesForCitites)
            {
                cities.Add(CreateCity(index, _random.Next(0, 10)));
            }

            CreateWorldRoadGraph();
            mainRoads = roads.Morph(s => s.Point);

        }

        private void DisplayGraphVertices(Graph<Point> graph)
        {
            var vertices = graph.Vertices.Select(p => p.ToVector3());
            var offset = Vector3.right;

            foreach (var (v, i) in vertices.Select((x, i) => (x, i)))
            {
                Gizmos.DrawSphere(v, 1);
            }
        }

        private void DisplayGraphCrossroads(Graph<Point> graph, List<int> vertices)
        {
            //foreach (var v in vertices.Select(i => graph.Vertices[i].ToVector3()))
            //{
            //    Gizmos.DrawSphere(v, 1);
            //}
        }


        private void DisplayGraphCities(List<City> cities)
        {
            foreach (City city in cities)
            {
                Gizmos.color = Color.magenta;
                foreach (var (a, b) in city.edges)
                {
                    Gizmos.DrawLine(_voronoiGraph.Vertices[a].ToVector3(), _voronoiGraph.Vertices[b].ToVector3());
                }

                foreach (var a in city.sites)
                    Gizmos.DrawSphere(a.Point.ToVector3(), 1);
            }
        }


        private void DisplayGraphEdges(Graph<Point> graph)
        {
            var edges = graph.Edges
                .Select(edge => (graph.Vertices[edge.Item1], graph.Vertices[edge.Item2]))
                .Select(edge => (edge.Item1.ToVector3(), edge.Item2.ToVector3()));

            foreach (var (s, e) in edges) Gizmos.DrawLine(s, e);
        }

        private void OnDrawGizmos()
        {

            if (debug.displayVertices)
            {
                Gizmos.color = Color.white;
                DisplayGraphVertices(_basicGraph.Morph(l => l.Point));
            }

            if (debug.displayEdges)
            {
                Gizmos.color = Color.white;
                DisplayGraphEdges(_basicGraph.Morph(l => l.Point));
            }

            if (debug.displayCrossroads)
            {
                Gizmos.color = Color.magenta;
                DisplayGraphCrossroads(_basicGraph.Morph(l => l.Point), verticesForRoads);
            }

            if (debug.displayCities)
            {
                Gizmos.color = Color.magenta;
                DisplayGraphCities(cities);
            }

            if (debug.displayFieldBoundaries)
            {
                Gizmos.color = Color.white;

                foreach (var city in cities)
                    DisplayGraphEdges(city.fieldBoundaries);
            }

            if (debug.displayCityRoads)
            {
                Gizmos.color = Color.green;

                foreach (var city in cities)
                {
                    DisplayGraphEdges(city.roads);
                    DisplayGraphVertices(city.roads);
                }
            }


            if (debug.displayWorldRoads)
            {
                // Gizmos.color = new Color(0.254f, 0.127f, 0.156f);
                Gizmos.color = Color.blue;
                DisplayGraphEdges(mainRoads);
            }
        }
    }
}