using System.Globalization;

namespace OSMDatastructure
{
    public class Coordinates
    {
        public float lat { get;  }
        public float lon { get; }

        public Coordinates(float lat, float lon)
        {
            this.lat = lat;
            this.lon = lon;
        }

        private const float decimalCoordsSave = 10000;
        private const ulong offset = 10000000;
        //Latitude maxChars = 7
        //Longitude maxChars = 8
        public ulong GetHash()
        {
            ulong latHash = Convert.ToUInt64((this.lat + 90) * decimalCoordsSave);
            ulong lonHash = Convert.ToUInt64((this.lon + 180) * decimalCoordsSave);
            return latHash * offset + lonHash;
        }

        public ulong GetRegionHash()
        {
            float latRegion = this.lat - this.lat % Region.regionSize;
            float lonRegion = this.lon - this.lon % Region.regionSize;
            ulong latHash = Convert.ToUInt64((latRegion + 90) * decimalCoordsSave);
            ulong lonHash = Convert.ToUInt64((lonRegion + 180) * decimalCoordsSave);
            return latHash * offset + lonHash;
        }

        public static Coordinates GetFromHash(ulong hash)
        {
            ulong latHash = (hash / offset) - 90;
            ulong lonHash = (hash % offset) - 180;
            float lat = Convert.ToSingle(latHash) / decimalCoordsSave;
            float lon = Convert.ToSingle(lonHash) / decimalCoordsSave;
            return new Coordinates(lat, lon);
        }

        public override string ToString()
        {
            return string.Format("{0} {1}", this.lat.ToString(CultureInfo.InvariantCulture), this.lon.ToString(CultureInfo.InvariantCulture));
        }
    }
}