using System;
using Godot;

public class TimestampId {
	//Base32 encode with encoding variant sort - ported from Bluesky official code
	private const string S32_CHAR = "234567abcdefghijklmnopqrstuvwxyz";

	public static string S32Encode(long value) {
		string s = "";
		while (value > 0) {
			int c = (int) (value % 32);
			value >>= 5;
			s = S32_CHAR[c] + s;
		}
		return s;
	}

	public static long S32Decode(string value) {
		long i = 0;
			foreach (char c in value) {
				i = i * 32 + S32_CHAR.IndexOf(c);
			}
		return i;
	}

	public static string EncodeTid(DateTime timestamp) {
		//Bsky uses a clock ID since JS time doesn't have microseconds,
		//so we'll kind of match that!
		long baseTime = ((DateTimeOffset)timestamp).ToUnixTimeMilliseconds();
		string millis = S32Encode(baseTime*1000);
		string micros = S32Encode(timestamp.Microsecond).PadLeft(2, '2');
		return $"{millis}{micros}";
	}
}