using Landmark.OLA.Models.OnlineBanking;
using System.Security.Authentication;
using System.Xml.Linq;

namespace OnlineBankingAuth.Parsers
{
    public class AuthTokenParser : IAuthTokenParser
    {

        public AuthTokenResponse ParseAuthTokenResponse(XElement xElement)
        {
            try
            {
                var accessToken = (string)xElement.Element("access_token");
                if (String.IsNullOrEmpty(accessToken))
                {
                    return ParseErroneousAuthTokenResponse(xElement); 
                }
                var authToken = new AuthToken
                {

                    DiFiid = (string)xElement.Element("di_fiid"),
                    DiFicustomer = (string)xElement.Element("di_ficustomer"),
                    DiMemberNumber = (string)xElement.Element("di_member_number"),
                    AccessToken = (string)xElement.Element("access_token"),
                    ExpiresIn = (string)xElement.Element("expires_in"),
                    RefreshToken = (string)xElement.Element("refresh_token"),
                    RefreshTokenExpiresIn = (string)xElement.Element("refresh_token_expires_in")
                };

                var authTokenResponse = new AuthTokenResponse
                {
                    Token = authToken,
                    Status = null
                };

                return authTokenResponse;
            }
            catch (Exception e)
            {
                throw new AuthenticationException($"Could not parse response from IdP vendor. {e.Message}, {e.StackTrace}");
            }

        }

        private AuthTokenResponse ParseErroneousAuthTokenResponse(XElement xElement)
        {
            var messageElement = (XElement)xElement.FirstNode;
            var errorElement = (XElement)xElement.FirstNode.NextNode;

            var errorType = (XElement)errorElement.FirstNode;
            var errorCode = (XElement)errorElement.FirstNode.NextNode;
            var errorMessage = (XElement)errorElement.FirstNode.NextNode.NextNode;

            var error = new AuthTokenError
            {
                ErrorType = errorType.Value,
                ErrorCode = errorCode.Value,
                ErrorMessage = errorMessage.Value
            };

            var authTokenStatus = new AuthTokenStatus
            {
                StatusMessage = messageElement.Value,
                ErrorInfo = error
            };

            return new AuthTokenResponse
            {
                Status = authTokenStatus
            };
        }
    }
}