using System.Globalization;
using System.Text.Json.Serialization;

namespace OSMDatastructure.Graph;

[Serializable]
public class Coordinates
{
    public float latitude { get; }
    public float longitude { get; }

    [JsonConstructor]
    public Coordinates(float latitude, float longitude)
    {
        this.latitude = latitude;
        this.longitude = longitude;
    }

    public override bool Equals(object? obj)
    {
        if (obj == null || obj.GetType() != this.GetType())
            return false;
        Coordinates convObj = (Coordinates)obj;
        return convObj.latitude.Equals(this.latitude) && convObj.longitude.Equals(longitude);
    }

    public static ulong GetRegionHashCode(float latitude, float longitude)
    {
        float latRegion = latitude - latitude % Region.RegionSize;
        float lonRegion = longitude - longitude % Region.RegionSize;
        return GetHashCode(latRegion, lonRegion);
    }

    public static ulong GetRegionHashCode(Coordinates coordinates)
    {
        return GetRegionHashCode(coordinates.latitude, coordinates.longitude);
    }
    
    private const float decimalCoordsSave = 10000; //Latitude maxChars = 7
    private const ulong offset = 10000000; //Longitude maxChars = 8
    public static ulong GetHashCode(float latitude, float longitude)
    {
        ulong latHash = Convert.ToUInt64((latitude + 90) * decimalCoordsSave);
        ulong lonHash = Convert.ToUInt64((longitude + 180) * decimalCoordsSave);
        return latHash * offset + lonHash;
    }

    public override string ToString()
    {
        return
            $"Coordinates lat:{latitude.ToString(NumberFormatInfo.InvariantInfo)} lon:{longitude.ToString(CultureInfo.InvariantCulture)}";
    }
}