public static ImmutableHashSet GetAllPathPrefixes()

in src/tooling/docs-assembler/Navigation/GlobalNavigationFile.cs [55:143]
80 lines of code
23 McCabe index (conditional complexity)

	public static ImmutableHashSet<Uri> GetAllPathPrefixes(AssembleContext context) =>
		GetSourceUris("toc", context);

	public static ImmutableHashSet<Uri> GetPhantomPrefixes(AssembleContext context) =>
		GetSourceUris("phantoms", context);

	private static ImmutableHashSet<Uri> GetSourceUris(string key, AssembleContext context)
	{
		var reader = new YamlStreamReader(context.NavigationPath, context.Collector);
		var set = new HashSet<Uri>();
		foreach (var entry in reader.Read())
		{
			if (entry.Key == key && key == "toc")
				ReadPathPrefixes(reader, entry.Entry, set);
			if (entry.Key == key && key == "phantoms")
				ReadPhantomTocs(reader, entry.Entry, set);
		}
		return set.ToImmutableHashSet();

		static void ReadPhantomTocs(YamlStreamReader reader, KeyValuePair<YamlNode, YamlNode> entry, HashSet<Uri> hashSet)
		{
			if (entry.Value is not YamlSequenceNode sequence)
			{
				reader.EmitWarning($"'{entry.Value}' is not an array");
				return;
			}

			foreach (var tocEntry in sequence.Children.OfType<YamlMappingNode>())
			{
				foreach (var child in tocEntry.Children)
				{
					var key = ((YamlScalarNode)child.Key).Value;
					switch (key)
					{
						case "toc":
							var source = reader.ReadString(child);
							if (source != null && !source.Contains("://"))
								source = ContentSourceMoniker.CreateString(NarrativeRepository.RepositoryName, source);
							if (source is not null)
								_ = hashSet.Add(new Uri(source));
							break;
					}
				}
			}
		}

		static void ReadPathPrefixes(YamlStreamReader reader, KeyValuePair<YamlNode, YamlNode> entry, HashSet<Uri> hashSet, string? parent = null)
		{
			if (entry.Key is not YamlScalarNode { Value: not null } scalarKey)
			{
				reader.EmitWarning($"key '{entry.Key}' is not string");
				return;
			}

			if (entry.Value is not YamlSequenceNode sequence)
			{
				reader.EmitWarning($"'{scalarKey.Value}' is not an array");
				return;
			}

			foreach (var tocEntry in sequence.Children.OfType<YamlMappingNode>())
			{
				var source = ReadToc(reader, tocEntry, ref parent, out var pathPrefix, out var sourceUri);
				if (sourceUri is not null && pathPrefix is not null)
				{
					var pathUri = new Uri($"{sourceUri.Scheme}://{pathPrefix.TrimEnd('/')}/");
					if (!hashSet.Add(pathUri))
						reader.EmitError($"Duplicate path prefix in the same repository: {pathUri}", tocEntry);
				}

				foreach (var child in tocEntry.Children)
				{
					var key = ((YamlScalarNode)child.Key).Value;
					switch (key)
					{
						case "children":
							if (source is null && pathPrefix is null)
							{
								reader.EmitWarning("toc entry has no toc or path_prefix defined");
								continue;
							}

							ReadPathPrefixes(reader, child, hashSet);
							break;
					}
				}
			}
		}
	}