import parsing

def Statement(object):
    """ The statement object of functions, to """
    pass

def get_names_for_scope(scope):
    """ Get all completions possible for the current scope. """
    comp = []
    start_scope = scope
    while scope:
        # class variables/functions are only availabe
        if not isinstance(scope, parsing.Class) or scope == start_scope:
            comp += scope.get_set_vars()
        scope = scope.parent
    return comp


def follow_path(scope, path):
    """
    Follow a path of python names.
    recursive!
    :returns: list(Scope)
    """
    comp = get_names_for_scope(scope)
    print path, comp

    path = list(path)
    name = path.pop(0)
    scopes = []

    # make the full comparison, because the names have to match exactly
    comp = [c for c in comp if [name] == list(c.names)]
    # TODO differentiate between the different comp input (some are overridden)
    for c in comp:
        p_class = c.parent.__class__
        if p_class == parsing.Class or p_class == parsing.Scope:
            scopes.append(c.parent)
        #elif p_class == parsing.Function:
        elif p_class == parsing.Statement:
            pass
        else:
            print 'error follow_path:', p_class, repr(c.parent)

    if path:
        new_scopes = []
        for s in tuple(scopes):
            new_scopes += follow_path(s, tuple(path))
        scopes = new_scopes
    return set(scopes)


def dbg(*args):
    if debug_function:
        debug_function(*args)


debug_function = None