using System.Security.Claims;
using System.Threading.Tasks;
using Autofac;
using Autofac.Core.Lifetime;
using FluentValidation;
using MediatR;
using Microsoft.Owin.Security;
using Microsoft.Owin.Security.OAuth;
using Zee.Z5.Domain.Commands;
using Zee.Z5.Domain.Commands.Validation;

namespace Zee.Z5.API.Setup.Auth
{
    public class AuthorizationServerProvider : OAuthAuthorizationServerProvider
    {
        private const string DeviceCredentialsKey = "device_credentials";
        private readonly ILifetimeScope _lifetimeScope;

        public AuthorizationServerProvider(ILifetimeScope lifetimeScope)
        {
            _lifetimeScope = lifetimeScope;
        }

        public override async Task ValidateClientAuthentication(OAuthValidateClientAuthenticationContext context)
        {
            var deviceId = context.Parameters["deviceId"];
            var deviceName = context.Parameters["deviceName"];
            var devicePlatform = context.Parameters["devicePlatform"];

            var deviceCredentials = new DeviceCredentials(deviceId, deviceName, devicePlatform);
            var validator = new DeviceCredentialsValidator();

            //TODO Create own extension method for rising ZeeApplicationException
            await validator.ValidateAndThrowAsync(deviceCredentials);

            context.OwinContext.Set(DeviceCredentialsKey, deviceCredentials);
            context.Validated();
        }

        public override async Task GrantResourceOwnerCredentials(OAuthGrantResourceOwnerCredentialsContext context)
        {
            var command = new UserLoginCommand()
            {
                Username = context.UserName,
                Password = context.Password,
                Credentials = context.OwinContext.Get<DeviceCredentials>(DeviceCredentialsKey),
                AuthenticationType = context.Options.AuthenticationType
            };

            ClaimsIdentity identity;
            using (var scope = _lifetimeScope.BeginLifetimeScope(MatchingScopeLifetimeTags.RequestLifetimeScopeTag))
            {
                var mediator = scope.Resolve<IMediator>();
                identity = await mediator.SendAsync(command);
            }

            var authProperties = new AuthenticationProperties();
            var ticket = new AuthenticationTicket(identity, authProperties);
            context.Validated(ticket);
        }
    }
}