using System;
using System.Collections.Generic;
using System.IO;

namespace MinecraftClient.Protocol.Keys
{
    public class PlayerKeyPair
    {
        public PublicKey PublicKey;

        public PrivateKey PrivateKey;

        public DateTime ExpiresAt;

        public DateTime RefreshedAfter; // Todo: add a timer

        private const string DataTimeFormat = "yyyy-MM-ddTHH:mm:ss.ffffffZ";

        public PlayerKeyPair(PublicKey keyPublic, PrivateKey keyPrivate, string expiresAt, string refreshedAfter)
        {
            PublicKey = keyPublic;
            PrivateKey = keyPrivate;
            try
            {
                ExpiresAt = DateTime.ParseExact(expiresAt, DataTimeFormat, System.Globalization.CultureInfo.InvariantCulture).ToUniversalTime();
                RefreshedAfter = DateTime.ParseExact(refreshedAfter, DataTimeFormat, System.Globalization.CultureInfo.InvariantCulture).ToUniversalTime();
            }
            catch
            {
                ExpiresAt = DateTime.Parse(expiresAt).ToUniversalTime();
                RefreshedAfter = DateTime.Parse(refreshedAfter).ToUniversalTime();
            }
        }

        public bool NeedRefresh()
        {
            return DateTime.Now.ToUniversalTime() > RefreshedAfter;
        }

        public bool IsExpired()
        {
            return DateTime.Now.ToUniversalTime() > ExpiresAt;
        }

        public long GetExpirationMilliseconds()
        {
            DateTimeOffset timeOffset = new(ExpiresAt);
            return timeOffset.ToUnixTimeMilliseconds();
        }

        public long GetExpirationSeconds()
        {
            DateTimeOffset timeOffset = new(ExpiresAt);
            return timeOffset.ToUnixTimeSeconds();
        }

        public static PlayerKeyPair FromString(string tokenString)
        {
            string[] fields = tokenString.Split(',');

            if (fields.Length < 6)
                throw new InvalidDataException("Invalid string format");

            PublicKey publicKey = new(pemKey: fields[0].Trim(),
                sig: fields[1].Trim(), sigV2: fields[2].Trim());

            PrivateKey privateKey = new(pemKey: fields[3].Trim());

            return new PlayerKeyPair(publicKey, privateKey, fields[4].Trim(), fields[5].Trim());
        }

        public override string ToString()
        {
            List<string> datas = new();
            datas.Add(Convert.ToBase64String(PublicKey.Key));
            if (PublicKey.Signature == null)
                datas.Add(String.Empty);
            else
                datas.Add(Convert.ToBase64String(PublicKey.Signature));
            if (PublicKey.SignatureV2 == null)
                datas.Add(String.Empty);
            else
                datas.Add(Convert.ToBase64String(PublicKey.SignatureV2));
            datas.Add(Convert.ToBase64String(PrivateKey.Key));
            datas.Add(ExpiresAt.ToString(DataTimeFormat));
            datas.Add(RefreshedAfter.ToString(DataTimeFormat));
            return String.Join(",", datas.ToArray());
        }
    }
}