from rest_framework.permissions import SAFE_METHODS, BasePermission


class IsAdmin(BasePermission):
    def has_permission(self, request, view):
        return bool(request.user and request.user.is_authenticated and request.user.is_admin)


class IsInstructor(BasePermission):
    def has_permission(self, request, view):
        return bool(
            request.user and request.user.is_authenticated and request.user.is_instructor
        )


class IsStudent(BasePermission):
    def has_permission(self, request, view):
        return bool(
            request.user and request.user.is_authenticated and request.user.is_student
        )


class IsAdminOrReadOnly(BasePermission):
    """Leitura para qualquer utilizador autenticado, escrita só para administradores."""

    def has_permission(self, request, view):
        if request.method in SAFE_METHODS:
            return bool(request.user and request.user.is_authenticated)
        return bool(request.user and request.user.is_authenticated and request.user.is_admin)


class IsAdminOrInstructor(BasePermission):
    def has_permission(self, request, view):
        return bool(
            request.user
            and request.user.is_authenticated
            and (request.user.is_admin or request.user.is_instructor)
        )