using System.Diagnostics.CodeAnalysis;
using System.Linq;
using System.ServiceModel;
using System.Threading.Tasks;
using gehGassi.Common;
using gehGassi.Core.Interfaces;
using Microsoft.Extensions.Options;
using VatServiceReference;

namespace gehGassi.External.Services
{
    /// <summary>
    /// Service der EU-UID-Nummern auf deren Gültigkeit prüft
    /// </summary>
    public class VatValidationService : IVatValidationService
    {
        private readonly IOptions<VatValidationSettings> _settings;

        /// <summary>
        /// Erstellt eine Instanz
        /// </summary>
        /// <param name="settings">Instanz eines IOptions VatValidationSettings</param>
        [ExcludeFromCodeCoverage]
        public VatValidationService(IOptions<VatValidationSettings> settings)
        {
            _settings = settings;
        }


        /// <summary>
        /// Prüft eine UID-Nummer auf deren Gültigkeit
        /// </summary>
        /// <param name="vat">UID-Nummer</param>
        /// <param name="countryIso2">ISO-2 Code des Landes</param>
        /// <returns>true wenn erfolgreich, false sonst</returns>
        public async Task<bool> IsValidAsync(string vat, string countryIso2)
        {
            if (string.IsNullOrWhiteSpace(vat))
                return false;
            if (string.IsNullOrWhiteSpace(countryIso2))
                return false;
            if (!_settings.Value.Enabled)
                return true;    

            var countriesToCheck = _settings.Value.Countries.Split(';');
            if (!countriesToCheck.Contains(countryIso2.ToUpper()))
                return true;

            if (string.IsNullOrWhiteSpace(vat))
                return false;

            System.Diagnostics.Debug.WriteLine($"VAT Prüfung: {vat} - {countryIso2}");
            var proxy = new VatServiceReference.checkVatPortTypeClient();
            proxy.Endpoint.Address = new EndpointAddress(_settings.Value.Address);

            bool valid;

            //Die Landeskennzeichnung wegnehmen
            vat = vat.ToUpperInvariant().Replace(countryIso2.ToUpperInvariant(), "");

            try
            {
                var result = await proxy.checkVatAsync(new checkVatRequest(countryIso2, vat));
                valid = result.valid;
            }
            catch
            {
                valid = false;
            }

            return valid;
        }
    }
}