baseimage-tutorial-framework/lib/tfw/linear_fsm.py

# Copyright (C) 2018 Avatao.com Innovative Learning Kft.
# All Rights Reserved. See LICENSE file for details.

from .fsm_base import FSMBase


class LinearFSM(FSMBase):
    # pylint: disable=anomalous-backslash-in-string
    """
    This is a state machine for challenges with linear progression, consisting of
    a number of steps specified in the constructor. It automatically sets up 2
    actions (triggers) between states as such:
    (0) --  step_1  --> (1) --  step_2  --> (2) --  step_3  --> (3) ... and so on
        \-step_next-/       \-step_next-/       \-step_next-/
    """
    def __init__(self, number_of_steps):
        self.states = list(map(str, range(number_of_steps)))
        self.transitions = []
        for index in self.states[:-1]:
            self.transitions.append({'trigger': f'step_{int(index)+1}', 'source': index, 'dest': str(int(index)+1)})
            self.transitions.append({'trigger': 'step_next', 'source': index, 'dest': str(int(index)+1)})
        super(LinearFSM, self).__init__()