'''

How to use a session parameter in code

BEST FOR ANNOUNCING A SMALL AMOUNT / GIVING TIPPS
example for an error in the treatment case
IF IT DOESNT MATTER
and a backfall variant for the show_partner_page

for complete code look @ baerlab_intro

BEST PRACTICE
3rd way is to set defaults, and overwrite them with the stuff given in the session_config

for complete code look into the real effort tasks @slider,countnumbers etc


'''

def creating_session(subsession):
    MSG_TREATMENT_MISSING = """
    FAILURE: The Session Config has a not specified Treatment, please check if Constant TREATMENTS 
    has the given config-treatment in its list
    """
    if 'treatment' in subsession.session.config:
        subsession.Treatment = subsession.session.config['treatment']
        if subsession.Treatment not in C.TREATMENTS:
            raise SystemExit(MSG_TREATMENT_MISSING)
    else:
        subsession.Treatment = 0 ### Control std

    if 'show_partner_page' in subsession.session.config:
        subsession.SHOW_PARTNER = subsession.session.config['show_partner_page']

    defaults = dict(
        num_sliders=36,  # anzahl der Slider
        num_columns=4,  # anzahl der Spalten
        attempts_per_slider=5,  # anzahl versuche pro Slider (mach sehr groß wenn nicht gebraucht)
        ## Delays hinzufügen?
        trial_delay=1,
        retry_delay=1 / 10,  ## Zeit zwischen falscher Eingabe und neu Versuch
    )
    subsession.session.params = {}
    for param in defaults:
        subsession.session.params[param] = subsession.session.config.get(param, defaults[param])