using System.Linq;
using System.Threading.Tasks;
using IdentityModel;
using Microsoft.AspNetCore.Authorization;

namespace xCommons.Authorization {
    public partial class RequiredRolesHandler : AuthorizationHandler<RequiredRolesRequirement> {
        protected override Task HandleRequirementAsync (
            AuthorizationHandlerContext context,
            RequiredRolesRequirement requirement
        ) {
            //
            var conatinsRole = context.User.HasClaim (c => c.Type == JwtClaimTypes.Role);
            if (!conatinsRole) {
                return Task.CompletedTask;
            }

            //
            var roleClaim = context.User.Claims.FirstOrDefault (c => c.Type == JwtClaimTypes.Role);
            if (roleClaim == null ||
                !requirement.Roles.Contains (roleClaim.Value)
            ) {
                return Task.CompletedTask;
            }

            //
            context.Succeed (requirement);
            return Task.CompletedTask;
        }
    }
}