from otree.api import *

class C(BaseConstants):
    NAME_IN_URL = 'session_full'
    PLAYERS_PER_GROUP = None
    NUM_ROUNDS = 1

class Subsession(BaseSubsession):
    pass

class Group(BaseGroup):
    pass

class Player(BasePlayer):
    pass

class MyPage(Page):
    def is_displayed(player):
        # Show to blocked participants OR if they failed to get added to session
        from session_utils import try_add_participant_if_space

        states = player.session.vars.get('participant_states', {})
        participant_state = states.get(player.participant.code, {})

        # If they're already marked as blocked, show this page
        if participant_state.get('status') == 'blocked':
            return True

        # If they're not in the session at all, try to add them
        # If that fails, they should see this page
        if player.participant.code not in states:
            can_join = try_add_participant_if_space(
                player.session,
                player.participant.code,
                'session_full'
            )
            return not can_join  # Show page if they CAN'T join

        return False

page_sequence = [MyPage]