private static OpenApiOAuthFlow ToOAuthFlow()

in src/Microsoft.OpenApi.CSharpAnnotations.DocumentGeneration/Extensions/XElementExtensions.cs [307:388]
67 lines of code
13 McCabe index (conditional complexity)

        private static OpenApiOAuthFlow ToOAuthFlow(this XElement element, string flowType,
            out IList<string> scopeNames)
        {
            var oAuthFlow = new OpenApiOAuthFlow();
            scopeNames = new List<string>();

            var authorizationUrl = element.Elements()
                .FirstOrDefault(p => p.Name == KnownXmlStrings.AuthorizationUrl)?.Value;

            var refreshUrl = element.Elements()
                .FirstOrDefault(p => p.Name == KnownXmlStrings.RefreshUrl)?.Value;

            var tokenUrl = element.Elements()
                .FirstOrDefault(p => p.Name == KnownXmlStrings.TokenUrl)?.Value;

            if (flowType == KnownXmlStrings.ImplicitFlow || flowType == KnownXmlStrings.AuthorizationCode)
            {
                if (authorizationUrl == null)
                {
                    throw new InvalidSecurityTagException(string.Format(
                        SpecificationGenerationMessages.UndocumentedAuthorizationUrl,
                        flowType));
                }
                oAuthFlow.AuthorizationUrl = new Uri(authorizationUrl);
            }

            if (flowType == KnownXmlStrings.Password
                || flowType == KnownXmlStrings.AuthorizationCode
                || flowType == KnownXmlStrings.ClientCredentials)
            {
                if (tokenUrl == null)
                {
                    throw new InvalidSecurityTagException(string.Format(
                        SpecificationGenerationMessages.UndocumentedTokenUrl,
                        flowType));
                }

                oAuthFlow.TokenUrl = new Uri(tokenUrl);
            }

            if (refreshUrl != null)
            {
                oAuthFlow.RefreshUrl = new Uri(refreshUrl);
            }

            var scopeElements = element.Elements()
                .Where(p => p.Name == KnownXmlStrings.Scope);

            if (!scopeElements.Any())
            {
                throw new InvalidSecurityTagException(string.Format(
                    SpecificationGenerationMessages.UndocumentedScopeForFlow,
                    flowType));
            }

            foreach (var scopeElement in scopeElements)
            {
                var name = scopeElement.Attribute(KnownXmlStrings.Name)?.Value;

                if (string.IsNullOrWhiteSpace(name))
                {
                    throw new InvalidSecurityTagException(string.Format(
                        SpecificationGenerationMessages.UndocumentedName,
                        KnownXmlStrings.Scope));
                }

                var description = scopeElement.Elements().FirstOrDefault(p => p.Name == KnownXmlStrings.Description)
                    ?.Value;

                if (string.IsNullOrWhiteSpace(description))
                {
                    throw new InvalidSecurityTagException(string.Format(
                        SpecificationGenerationMessages.UndocumentedDescription,
                        KnownXmlStrings.Scope));
                }

                scopeNames.Add(name);
                oAuthFlow.Scopes.Add(name, description);
            }

            return oAuthFlow;
        }