using System.Xml.Linq;
using Landmark.OLA.Models.Addresses;
using Landmark.OLA.Models.Addresses.Enums;

namespace USPS.Parsers
{
    public class AddressValidationResponseParser : IResponseParser<Address>
    {

        public bool CheckForError(XElement xdoc)
        {
            var elementAddress = xdoc.Element("Address");
            if (elementAddress == null)
            {
                return true;
            }
            var error = elementAddress.Element("Error");
            return (error != null);
        }

        public Address Parse(XElement xdoc)
        {
            if( xdoc == null )
            {
                throw new ArgumentNullException("Address xml is null");
            }

            var elementAddress = xdoc.Element("Address");
            if (elementAddress == null || elementAddress.Element("Error") != null)
            {
                throw new FormatException("Attempt to parse address that is in error.");
            }

            try
            {               
                var compareAddress = new Address
                {
                    // USPS considers unit numbers (ex: APT 204) to be Address1. Our app's models would consider these to be Address2. DO NOT CHANGE
                    Address2 = (string)elementAddress.Element("Address1"),
                    Address1 = (string)elementAddress.Element("Address2"),
                    City = (string)elementAddress.Element("City"),
                    State = MakeStateOptionEnum((string)elementAddress.Element("State")),
                    PostalCode = (string)elementAddress.Element("Zip5"),
                    PostalCodeExt = (string)elementAddress.Element("Zip4"),
                    Country = CountryOption.UnitedStates
                };

                return compareAddress;
            }
            catch
            {
                throw new FormatException("USPS XML is in an unexpected layout.");
            }
        }

        public static StateOption MakeStateOptionEnum(string state)
        {
            if (Enum.TryParse(state, out StateOption parsedState))
            {
                return parsedState;
            }
            else
            {
                throw new FormatException("USPS XML contains an unexpected 'State'");
            }
        }
    }
}