Improved code and branch coverage

Author: tsutomi

src/Deveel.Messaging.Connector.Facebook/Messaging/FacebookMessengerConnector.cs

@@ -430,8 +430,10 @@ private List<IMessage> ParseFacebookWebhook(MessageSource source)
             if (string.IsNullOrEmpty(senderId) || string.IsNullOrEmpty(recipientId))
                 return null;
 
-            // Extract message ID and timestamp
-            var messageId = messageProperty.GetProperty("mid").GetString() ?? Guid.NewGuid().ToString();
+            // Extract message ID and timestamp - handle missing mid property safely
+            var messageId = messageProperty.TryGetProperty("mid", out var midProperty) 
+                ? midProperty.GetString() ?? Guid.NewGuid().ToString()
+                : Guid.NewGuid().ToString();
             var timestamp = messageProperty.TryGetProperty("timestamp", out var timestampProperty)
                 ? DateTimeOffset.FromUnixTimeMilliseconds(timestampProperty.GetInt64()).DateTime
                 : DateTime.UtcNow;

src/Deveel.Messaging.Connector.Facebook/Messaging/FacebookService.cs

@@ -151,7 +151,7 @@ private static bool IsValidPageAccessToken(string token)
         private static void ValidateMessageRequest(FacebookMessageRequest request)
         {
             // Facebook Messenger Platform validation requirements
-            if (string.IsNullOrEmpty(request.Message.Text) && request.Message.Attachment == null)
+            if (string.IsNullOrWhiteSpace(request.Message.Text) && request.Message.Attachment == null)
                 throw new ArgumentException("Message must contain either text or attachment");
 
             if (!string.IsNullOrEmpty(request.Message.Text) && request.Message.Text.Length > 2000)
@@ -280,7 +280,10 @@ private static string ParseFacebookError(RestResponse response)
             }
             catch
             {
-                return $"HTTP {(int)response.StatusCode} {response.StatusCode}: {response.ErrorMessage}";
+                // When JSON parsing fails, return the raw content if it's not empty
+                return !string.IsNullOrEmpty(response.Content) 
+                    ? response.Content 
+                    : $"HTTP {(int)response.StatusCode} {response.StatusCode}: {response.ErrorMessage}";
             }
         }
 

…ookMessengerConnectorLoggerExtensions.cs …r.Facebook/Messaging/LoggerExtensions.cssrc/Deveel.Messaging.Connector.Facebook/Messaging/FacebookMessengerConnectorLoggerExtensions.cs renamed to src/Deveel.Messaging.Connector.Facebook/Messaging/LoggerExtensions.cs src/Deveel.Messaging.Connector.Facebook/Messaging/FacebookMessengerConnectorLoggerExtensions.cs renamed to src/Deveel.Messaging.Connector.Facebook/Messaging/LoggerExtensions.cs

@@ -10,7 +10,7 @@ namespace Deveel.Messaging
     /// <summary>
     /// Provides high-performance logging extensions for Facebook Messenger Connector operations using source-generated logging methods.
     /// </summary>
-    internal static partial class FacebookMessengerConnectorLoggerExtensions
+    internal static partial class LoggerExtensions
     {
         #region Initialization Logging