using Manager.DTOs;
using NetTopologySuite;
using NetTopologySuite.Geometries;
using System.Collections.Generic;
using System.Linq;
using System.Text.Json;
using System;

namespace ManagerService.Helpers
{
    public static class GeometryMapper
    {
        public static GeometryDTO ToDto(this Geometry geometry)
        {
            return geometry switch
            {
                Point point => new GeometryDTO
                {
                    type = "Point",
                    coordinates = new List<double> { point.X, point.Y }
                },
                LineString line => new GeometryDTO
                {
                    type = "LineString",
                    coordinates = line.Coordinates
                        .Select(coord => new List<double> { coord.X, coord.Y })
                        .ToList()
                },
                Polygon polygon => new GeometryDTO
                {
                    type = "Polygon",
                    coordinates = new List<List<List<double>>>
                {
                    polygon.ExteriorRing.Coordinates
                        .Select(coord => new List<double> { coord.X, coord.Y })
                        .ToList()
                }
                },
                _ => throw new NotSupportedException($"Geometry type {geometry.GeometryType} not supported.")
            };
        }

        public static Geometry FromDto(this GeometryDTO dto, GeometryFactory factory = null!)
        {
            factory ??= NtsGeometryServices.Instance.CreateGeometryFactory();

            return dto.type switch
            {
                "Point" => CreatePoint(dto, factory),
                "LineString" => CreateLineString(dto, factory),
                "Polygon" => CreatePolygon(dto, factory),
                _ => throw new NotSupportedException($"DTO type {dto.type} not supported.")
            };
        }

        private static Point CreatePoint(GeometryDTO dto, GeometryFactory factory)
        {
            var coords = ((JsonElement)dto.coordinates).Deserialize<List<double>>();
            return factory.CreatePoint(new Coordinate(coords[0], coords[1]));
        }

        private static LineString CreateLineString(GeometryDTO dto, GeometryFactory factory)
        {
            var coords = ((JsonElement)dto.coordinates).Deserialize<List<List<double>>>();
            var coordinates = coords.Select(c => new Coordinate(c[0], c[1])).ToArray();
            return factory.CreateLineString(coordinates);
        }

        private static Polygon CreatePolygon(GeometryDTO dto, GeometryFactory factory)
        {
            var rings = ((JsonElement)dto.coordinates).Deserialize<List<List<List<double>>>>();
            var exterior = rings.First().Select(c => new Coordinate(c[0], c[1])).ToArray();
            return factory.CreatePolygon(exterior);
        }
    }

}