Iceshrimp.NET/Iceshrimp.Backend/Core/Helpers/IdHelpers.cs

23 lines
No EOL
648 B
C#

using Iceshrimp.Backend.Core.Extensions;
using Visus.Cuid;
namespace Iceshrimp.Backend.Core.Helpers;
public static class IdHelpers
{
private const long Time2000 = 946684800000;
public static string GenerateSlowflakeId(DateTime? createdAt = null)
{
if (createdAt?.Kind is not null and not DateTimeKind.Utc)
createdAt = createdAt.Value.ToUniversalTime();
createdAt ??= DateTime.UtcNow;
var cuid = new Cuid2(8);
var now = (long)createdAt.Value.Subtract(DateTime.UnixEpoch).TotalMilliseconds;
var time = Math.Max(now - Time2000, 0);
var timestamp = time.ToBase36().PadLeft(8, '0');
return timestamp + cuid;
}
}