using Microsoft.ClearScript;
using Microsoft.ClearScript.V8;
using Npgsql;
using System;
using System.Collections.Generic;
using System.Data;
using System.Data.Common;
using System.IO;
using System.Linq;
using System.Text;
using System.Web;
using Turf.Models;

namespace Turf.cs
{
    public class Tools
    {
        public Tools() { }

        private V8Script v8Script;

        public static readonly string BaseDir = AppDomain.CurrentDomain.BaseDirectory;

        private static PostgreHelper _dbHelper;

        public static PostgreHelper DBHelper
        {
            get
            {
                if (null == _dbHelper)
                {
                    _dbHelper = new PostgreHelper();
                }

                return _dbHelper;
            }
        }

        public static string selectCoordinatesByCodeSql = "select ST_X(geom) x, ST_Y(geom) y from bs.s_explorationpoint b where dirid like @code and geom is not null";

        public static string selectCoordinates(string code)
        {
            DbParameter dp = new NpgsqlParameter("@code", code + "%");

            DataTable dt = DBHelper.GetDataTable(selectCoordinatesByCodeSql, dp);
            if (null == dt || 0 == dt.Rows.Count) return null;

            List<Coordinate> list = ModelHandler.FillModel<Coordinate>(dt);
            if (null == list || 0 == list.Count) return null;

            StringBuilder sb = new StringBuilder();
            sb.Append("[");
            foreach (Coordinate cs in list)
            {
                sb.Append(cs.ToString() + ",");
            }
            sb.Remove(sb.Length - 1, 1);
            sb.Append(']');

            return sb.ToString();
        }

        public static double CalcArea(string code)
        {
            using (V8ScriptEngine engine = new V8ScriptEngine())
            {
                engine.DocumentSettings.AccessFlags = DocumentAccessFlags.EnableFileLoading;
                engine.DefaultAccess = ScriptAccess.Full;

                string jsFile = Path.Combine(BaseDir, "js\\turf.min.6.5.js");
                V8Script script = engine.CompileDocument(jsFile);
                engine.Execute(script);

                string cs = selectCoordinates(code);
                if (string.IsNullOrEmpty(cs)) return 0;

                object obj = engine.Invoke("pointsToPolygon", cs);

                return null == obj ? 0 : Convert.ToDouble(obj);
            }
        }
    }
}