using System;
using System.Collections.Generic;
using System.Linq;
using System.Security.Claims;
using System.Security.Principal;
using System.Text;
using System.Threading.Tasks;
using Microsoft.AspNet.SignalR;
using Microsoft.AspNet.SignalR.Hubs;
using Step.Config;
using Step.Database.Controllers;
using Step.Model;
using static Step.Utils.Constants;
using Step.Utils;

namespace Step.Attributes
{
    class SignalRAuthorizeAttribute : AuthorizeAttribute
    {
        public string FunctionAccess;
        public ACTIONS Action;

        protected override bool UserAuthorized(IPrincipal user)
        {
            if (!base.UserAuthorized(user))
                return false;

            // Get user level stored in the bearer token   
            ClaimsIdentity identity = user.Identity as ClaimsIdentity;
            var userRoleLevel = identity.Claims.Where(c => c.Type == ROLE_LEVEL_KEY).SingleOrDefault();
            // User data not found -> not authorized
            if (userRoleLevel == null)
                return false;

            // check authorization
            if (!CheckAuthorization(Convert.ToInt32(userRoleLevel.Value), FunctionAccess))
                return false;

            return true; 
        }

        private bool CheckAuthorization(int userLevel, string functionName)
        {
            try
            {
                using (FunctionAccessController acController = new FunctionAccessController())
                {

                    // Read from db category levels
                    FunctionAccessModel functionAccess = acController.FindEnabledFunctionByName(functionName);
                    if (functionAccess != null && StartupConfigController.CheckAreaStatus(functionAccess.Area))
                    {
                        if (Action == ACTIONS.READ)
                        {   // Check read permissions 
                            if (functionAccess.ReadLevelMin > userLevel)
                                return false; // Not authorized
                        }
                        else
                        {   // Check write permissions
                            if (functionAccess.WriteLevelMin > userLevel)
                                return false; // Not authorized
                        }
                    }
                    else
                    {
                        return false;
                    }
                }
            }
            catch (Exception ex)
            {
                ExceptionManager.Manage(ex);
            }
            // Authorized
            return true;
            }
        }
}