using System;
using System.Linq;
using System.Security.Claims;
using System.Web.Http;
using System.Web.Http.Controllers;
using Step.Database.Controllers;
using Step.Config;
using static Step.Utils.Constants;
using Step.Model.DatabaseModels;

namespace Step
{
    class WebApiAuthorizeAttribute : AuthorizeAttribute
    {
        public string FunctionAccess;
        public ACTIONS Action;
        protected override bool IsAuthorized(HttpActionContext actionContext)
        {
            if (!base.IsAuthorized(actionContext))
                return false;

            // Get user level stored in the bearer token   
            ClaimsPrincipal principal = actionContext.RequestContext.Principal as ClaimsPrincipal;
            var userRoleLevel = principal.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)
        {
            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;
                }

                // Authorized
                return true;
            }
        }
    }
}