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Parsing/HtmlParsingHelpers.cs

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+using System;
+using System.Text.RegularExpressions;
+using HtmlAgilityPack;
+
+namespace CRAWLER.Parsing;
+
+internal static class HtmlParsingHelpers
+{
+    public static string NormalizeWhitespace(string value)
+    {
+        if (string.IsNullOrWhiteSpace(value))
+        {
+            return null;
+        }
+
+        var decoded = HtmlEntity.DeEntitize(value);
+        decoded = decoded.Replace('\u00A0', ' ');
+        decoded = Regex.Replace(decoded, @"\s+", " ");
+        return decoded.Trim();
+    }
+
+    public static string NormalizeLabel(string value)
+    {
+        return NormalizeWhitespace(value)
+            ?.Replace(" :", ":")
+            .Trim(':', ' ');
+    }
+
+    public static string MakeAbsoluteUrl(string baseUrl, string urlOrPath)
+    {
+        if (string.IsNullOrWhiteSpace(urlOrPath))
+        {
+            return null;
+        }
+
+        if (Uri.TryCreate(urlOrPath, UriKind.Absolute, out var absoluteUri))
+        {
+            return absoluteUri.ToString();
+        }
+
+        var baseUri = new Uri(baseUrl.TrimEnd('/') + "/");
+        return new Uri(baseUri, urlOrPath.TrimStart('/')).ToString();
+    }
+
+    public static string ExtractNodeTextExcludingChildParagraph(HtmlNode node)
+    {
+        if (node == null)
+        {
+            return null;
+        }
+
+        var clone = node.CloneNode(true);
+        var paragraphs = clone.SelectNodes("./p");
+        if (paragraphs != null)
+        {
+            foreach (var paragraph in paragraphs)
+            {
+                paragraph.Remove();
+            }
+        }
+
+        return NormalizeWhitespace(clone.InnerText);
+    }
+}