using System.Collections.Generic;
using System.Linq;
using Assets.Common;
using Assets.Voronoi;

namespace Assets.Cities
{
    public class City
    {
        public Graph<MapSite> startGraph;
        public List<MapSite> 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<MapSite> startGraph)
        {
            this.startGraph = startGraph;

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

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

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

        private void FixBoundaryEdges(MapSite 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.Boundary.Select(i => (i, points[i])).Append((-1, site.Center))).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])) };
        }
    }
}