refactor: handle empty ThunderSkill URL

Author: VitaliiAndreev

Core.Web.WarThunder/Helpers/ThunderSkillParser.cs

@@ -54,11 +54,18 @@ public void Load()
 
             var url = Settings.ThunderSkillUrl;
 
-            LogDebug(ECoreLogMessage.Reading.Format(url));
+            if (string.IsNullOrWhiteSpace(url))
             {
-                _mainHtmlNode = GetHtmlDocumentNode(url);
+                LogWarn("ThunderSkill (TS) URL is empty. Makes sure to copy TS related settings from the default \"Client.Wpf.Settings.xml\".");
+            }
+            else
+            {
+                LogDebug(ECoreLogMessage.Reading.Format(url));
+                {
+                    _mainHtmlNode = GetHtmlDocumentNode(url);
+                }
+                LogDebug(ECoreLogMessage.FinishedReading.Format(url));
             }
-            LogDebug(ECoreLogMessage.FinishedReading.Format(url));
 
             IsLoaded = true;
         }
@@ -90,7 +97,7 @@ private IDictionary<string, VehicleUsage> GetVehicleUsage(string tableXPath)
             if (string.IsNullOrWhiteSpace(tableXPath))
                 return vehicleUsageRecords;
 
-            var table = _mainHtmlNode.SelectSingleNode(tableXPath);
+            var table = _mainHtmlNode?.SelectSingleNode(tableXPath);
 
             if (table is HtmlNode)
             {

Core.Web/Helpers/HtmlParser.cs

@@ -33,6 +33,9 @@ public HtmlNode GetHtmlDocumentNode(string url, int retryAttempts = EInteger.Num
             if (retryAttempts.IsZero())
                 throw new TimeoutException(EWebLogMessage.FailedToRead.Format(url), internalException);
 
+            if (string.IsNullOrWhiteSpace(url))
+                throw new ArgumentException($"\"{nameof(url)}\" is null or empty.");
+
             try
             {
                 return new HtmlWeb()