From 53886fa6bf647df3ddad99ff4df00b15c78e111c Mon Sep 17 00:00:00 2001
From: Florian Zevedei <florian.dahn@fdsoftware.de>
Date: Sat, 3 Feb 2024 01:39:12 +0100
Subject: [PATCH] Adding exception for too long callback data.

- right now only in DEBUG compilation and only for the static operator
---
 TelegramBotBase/Constants/Telegram.cs         |  5 +++++
 .../CallbackDataTooLongException.cs           | 21 +++++++++++++++++++
 TelegramBotBase/Form/CallbackData.cs          | 16 ++++++++++++--
 3 files changed, 40 insertions(+), 2 deletions(-)
 create mode 100644 TelegramBotBase/Exceptions/CallbackDataTooLongException.cs

diff --git a/TelegramBotBase/Constants/Telegram.cs b/TelegramBotBase/Constants/Telegram.cs
index a2837d7..f91642d 100644
--- a/TelegramBotBase/Constants/Telegram.cs
+++ b/TelegramBotBase/Constants/Telegram.cs
@@ -16,4 +16,9 @@ public static class Telegram
     public const int MaxReplyKeyboardCols = 12;
 
     public const int MessageDeletionsPerSecond = 30;
+
+    /// <summary>
+    /// The maximum length of callback data. Will raise an exception of it exceeds it.
+    /// </summary>
+    public const int MaxCallBackDataBytes = 64;
 }
\ No newline at end of file
diff --git a/TelegramBotBase/Exceptions/CallbackDataTooLongException.cs b/TelegramBotBase/Exceptions/CallbackDataTooLongException.cs
new file mode 100644
index 0000000..300e0e5
--- /dev/null
+++ b/TelegramBotBase/Exceptions/CallbackDataTooLongException.cs
@@ -0,0 +1,21 @@
+using System;
+using Telegram.Bot.Exceptions;
+
+namespace TelegramBotBase.Exceptions;
+
+public sealed class CallbackDataTooLongException : Exception
+{
+    //public override string Message =>
+    //    $"You have exceeded the maximum {Constants.Telegram.MaxCallBackDataBytes} bytes.";
+
+    static ApiRequestException _innerException = new Telegram.Bot.Exceptions.ApiRequestException("Bad Request: BUTTON_DATA_INVALID", 400);
+
+    static String _message = $"You have exceeded the maximum {Constants.Telegram.MaxCallBackDataBytes} bytes of callback data.\r\nThis is a pre-sending message from the TelegramBotBase framework.\r\nread more: https://core.telegram.org/bots/api#inlinekeyboardbutton";
+
+    public CallbackDataTooLongException() : base(_message, _innerException)
+    {
+
+    }
+
+
+}
diff --git a/TelegramBotBase/Form/CallbackData.cs b/TelegramBotBase/Form/CallbackData.cs
index 8385551..84c699e 100644
--- a/TelegramBotBase/Form/CallbackData.cs
+++ b/TelegramBotBase/Form/CallbackData.cs
@@ -1,4 +1,6 @@
 using Newtonsoft.Json;
+using System.Text;
+using TelegramBotBase.Exceptions;
 
 namespace TelegramBotBase.Form;
 
@@ -30,7 +32,7 @@ public class CallbackData
     ///     Serializes data to json string
     /// </summary>
     /// <returns></returns>
-    public string Serialize()
+    public string Serialize(bool throwExceptionOnOverflow = false)
     {
         var s = "";
         try
@@ -41,6 +43,16 @@ public class CallbackData
         {
         }
 
+#if DEBUG
+
+        //Data is over 64 bytes
+        if(throwExceptionOnOverflow && Encoding.UTF8.GetByteCount(s) > Constants.Telegram.MaxCallBackDataBytes)
+        {
+            throw new CallbackDataTooLongException();
+        }
+
+#endif
+
         return s;
     }
 
@@ -65,5 +77,5 @@ public class CallbackData
         return null;
     }
 
-    public static implicit operator string(CallbackData callbackData) => callbackData.Serialize();
+    public static implicit operator string(CallbackData callbackData) => callbackData.Serialize(true);
 }