Fix WebDAV GetRelativePath to handle full URLs from server responses

src/SharpSync/Storage/WebDavStorage.cs

@@ -930,14 +930,42 @@ private string GetFullPath(string relativePath) {
     }
 
     private string GetRelativePath(string fullUrl) {
-        var prefix = string.IsNullOrEmpty(RootPath) ? _baseUrl : $"{_baseUrl}/{RootPath}";
-
-        if (fullUrl.StartsWith(prefix)) {
-            var relativePath = fullUrl.Substring(prefix.Length).Trim('/');
-            return string.IsNullOrEmpty(relativePath) ? "/" : relativePath;
+        // The fullUrl can be either a full URL (http://server/path) or just a path (/path)
+        // We need to strip the base URL and RootPath to get the relative path
+
+        // Extract the path portion if it's a full URL
+        string path;
+        if (Uri.TryCreate(fullUrl, UriKind.Absolute, out var uri)) {
+            // It's a full URL - get the path component and decode it
+            path = Uri.UnescapeDataString(uri.AbsolutePath);
+        } else {
+            // It's already a path
+            path = fullUrl;
         }
-
-        return fullUrl;
+
+        // Remove leading slash for consistency
+        path = path.TrimStart('/');
+
+        // If there's no root path, return the path as-is (trimming trailing slashes)
+        if (string.IsNullOrEmpty(RootPath)) {
+            return path.TrimEnd('/');
+        }
+
+        // Normalize the root path (no leading/trailing slashes)
+        var normalizedRoot = RootPath.Trim('/');
+
+        // The path should start with RootPath/
+        if (path.StartsWith($"{normalizedRoot}/")) {
+            return path.Substring(normalizedRoot.Length + 1).TrimEnd('/');
+        }
+
+        // If it's exactly the root path itself (directory listing)
+        if (path == normalizedRoot || path == $"{normalizedRoot}/") {
+            return "";
+        }
+
+        // Otherwise return as-is (trim trailing slashes)
+        return path.TrimEnd('/');
     }
 
     private bool _rootPathCreated;

tests/SharpSync.Tests/Storage/WebDavStorageTests.cs

@@ -606,11 +606,6 @@ public async Task ListItemsAsync_WithFiles_ReturnsAllItems() {
             await Task.Delay(100);
         }
 
-        // Debug output
-        foreach (var item in items!) {
-            System.Diagnostics.Debug.WriteLine($"Found item: {item.Path}, IsDirectory: {item.IsDirectory}");
-        }
-
         // Assert
         Assert.Equal(3, items.Count);
         Assert.Contains(items, i => i.Path.EndsWith("file1.txt") && !i.IsDirectory);