satellite-provider/SatelliteProvider.DataAccess/TypeHandlers/TileSourceTypeHandler.cs

using System.Data;
using Dapper;
using SatelliteProvider.Common.Enums;

namespace SatelliteProvider.DataAccess.TypeHandlers;

// AZ-484: TileSource needs an explicit string mapping because the multi-word
// member 'GoogleMaps' must round-trip as the snake_case wire value 'google_maps'
// per the v1.0.0 tile-storage contract. The generic EnumStringTypeHandler<T>
// only does ToString().ToLowerInvariant(), which would emit 'googlemaps'.
public class TileSourceTypeHandler : SqlMapper.TypeHandler<TileSource>
{
    public const string GoogleMapsWireValue = "google_maps";
    public const string UavWireValue = "uav";

    public override TileSource Parse(object value)
    {
        if (value is null || value is DBNull)
        {
            throw new DataException("Cannot parse null DB value into enum TileSource");
        }

        var s = value as string ?? value.ToString();
        if (string.IsNullOrEmpty(s))
        {
            throw new DataException("Cannot parse empty DB value into enum TileSource");
        }

        return s.ToLowerInvariant() switch
        {
            GoogleMapsWireValue => TileSource.GoogleMaps,
            UavWireValue => TileSource.Uav,
            _ => throw new DataException($"DB value '{s}' is not a defined member of enum TileSource"),
        };
    }

    public override void SetValue(IDbDataParameter parameter, TileSource value)
    {
        parameter.Value = ToWireValue(value);
        parameter.DbType = DbType.String;
    }

    public static string ToWireValue(TileSource value) => value switch
    {
        TileSource.GoogleMaps => GoogleMapsWireValue,
        TileSource.Uav => UavWireValue,
        _ => throw new ArgumentOutOfRangeException(nameof(value), value, "Unknown TileSource"),
    };
}