*scratch*.py

# Two problems to solve:
# Q: How to pass state in a DAG
# A: ???

# Q: How to pass between DAGs?
# A: Use event payload.

# Q: How to early terminate a running DAG?
# A: Using priority to terminate existing DAGs.

# Looping different poses

# A -> B -> C
# ^ --------v

# Loading Area - Z

def rotate(target_pose, pose_sequence=['A', 'B', 'C']):
    """
    Args:
        target_pose: the pose the rotate would navigate to now.
        pose_sequence: The sequence of poses to rotate between.
    """
    # Validation
    assert(target_pose in pose_sequence)

    # RobotOperation
    nav(pose=target_pose)

    # ButtonOperation
    show_buttons([
        Button(
            name='Go to Loading',
            event='loading',
            payload={
                # This allows the new DAG to take over the current running robot.
                priority: 10,
            },
        )
    ])

    # WaitOperation
    wait(5*60) # wait 5 minute

    ni = (pose_sequence.index(target_pose) + 1) % len(pose_sequence)
    next_pose = pose_sequence(ni)

    # EventOperation
    trigger_event('rotate', {target_pose: next_pose})


# Pre-defined
LOADING_POS = 'Loading Position'

def loading(from_pose):
    # RobotOperation
    nav(pose=LOADING_POS)

    # ...

    # ButtonOperation
    show_buttons([
        Button(
            name='Back to Rotation',
            event='rotate',
            payload={
                target_pose: from_pose,
            },
        )
    ])



add_event_listener('rotate', rotate)
add_event_listener('loading', loading)