Basic support for minecraft 1.19 (#2084)

* merge commit from milutinke
* chat signature & encrypted login
* Bug fix :EncryptionResponse format error below 1.18.2
* Implemented chat command signature
* Chat message parsing and verification for 1.19
* Add signature settings
* Update Simplified Chinese Translation
* Clear up comments
* Fix wrong variable naming
* Bug fix: SignatureV2 Processing

MinecraftClient/Protocol/ProfileKey/PlayerKeyPair.cs

@@ -0,0 +1,79 @@
+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 = "O";
+
+        public PlayerKeyPair(PublicKey keyPublic, PrivateKey keyPrivate, string expiresAt, string refreshedAfter)
+        {
+            PublicKey = keyPublic;
+            PrivateKey = keyPrivate;
+            ExpiresAt = DateTime.Parse(expiresAt).ToUniversalTime();
+            RefreshedAfter = DateTime.Parse(refreshedAfter).ToUniversalTime();
+        }
+
+        public bool NeedRefresh()
+        {
+            return DateTime.Now.ToUniversalTime() > this.RefreshedAfter;
+        }
+
+        public bool IsExpired()
+        {
+            return DateTime.Now.ToUniversalTime() > this.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 PublicKey(pemKey: fields[0].Trim(),
+                sig: fields[1].Trim(), sigV2: fields[2].Trim());
+
+            PrivateKey privateKey = new PrivateKey(pemKey: fields[3].Trim());
+
+            return new PlayerKeyPair(publicKey, privateKey, fields[4].Trim(), fields[5].Trim());
+        }
+
+        public override string ToString()
+        {
+            List<string> datas = new List<string>();
+            datas.Add(Convert.ToBase64String(PublicKey.Key));
+            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());
+        }
+    }
+}