using Autofac;
using GreenTree.Nachtragsmanagement.Core;
using GreenTree.Nachtragsmanagement.Core.Authentication;
using GreenTree.Nachtragsmanagement.Services.User;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Web;
using System.Web.Mvc;

namespace GreenTree.Nachtragsmanagement.Web.Framework.Authorization
{
    public class RoleAuthorizeAttribute : AuthorizeAttribute
    {
        #region Fields

        private readonly IAuthenticationService _authenticationService;
        private readonly IUserHelper _userHelper;
        private readonly string[] _allowedFunctions;
        private readonly bool _showNotAuthorized;

        #endregion

        /// <summary>
        /// Initializes a new instance of the RoleAuthorizeAttribute class
        /// </summary>
        /// <param name="showNotAuthorized">Determines if a NotAuthorized message or a login redirection is made.</param>
        /// <param name="functions">The functions needed.</param>
        public RoleAuthorizeAttribute(bool showNotAuthorized, params string[] functions)
        {
            _showNotAuthorized = showNotAuthorized;
            _allowedFunctions = functions;

            _authenticationService = Singleton<IContainer>.Instance.Resolve<IAuthenticationService>();
            _userHelper = Singleton<IContainer>.Instance.Resolve<IUserHelper>();
        }

        protected override bool AuthorizeCore(HttpContextBase httpContext)
        {
            var user = _userHelper.FromCookies();

            if (user == null)
                return false;

            if (!_allowedFunctions.Any())
                return true;

            foreach (var role in user.Roles)
            {
                foreach (var function in role.Functions)
                {
                    var allowed = _allowedFunctions.Contains(function.Description);

                    if (allowed)
                        return true;
                }
            }

            return false;
        }

        protected override void HandleUnauthorizedRequest(AuthorizationContext filterContext)
        {
            if (!_showNotAuthorized)
                filterContext.Result = new RedirectResult("~/login");
            else
                filterContext.Result = new RedirectResult("~/global/notauthorized");
        }
    }
}