#!/usr/bin/env python3
# From https://pybay.com/site_media/slides/raymond2017-keynote/threading.html
import threading, queue


_counter:int = 0

counter_queue = queue.Queue()

def counter_manager() -> None:
    'I have EXCLUSIVE rights to update the _counter variable'
    global _counter

    while True:
        increment = counter_queue.get()
        _counter += increment
        print_queue.put([
            'The count is %d' % _counter,
            '---------------'])
        counter_queue.task_done()


print_queue = queue.Queue()

def print_manager() -> None:
    'I have EXCLUSIVE rights to call the "print" keyword'
    while True:
        job = print_queue.get()
        for line in job:
            print(line)
        print_queue.task_done()


def worker() -> None:
    'My job is to increment the counter and print the current count'
    counter_queue.put(1)


def run() -> None:
    # Set up the counter manager
    t = threading.Thread(target=counter_manager)
    t.daemon = True
    t.start()
    del t

    # Set up the print manager
    t = threading.Thread(target=print_manager)
    t.daemon = True
    t.start()
    del t

    # Start doing work
    print_queue.put(['Starting up'])
    worker_threads = []
    for _ in range(10):
        t = threading.Thread(target=worker)
        worker_threads.append(t)
        t.start()
    for t in worker_threads:
        t.join()

    counter_queue.join()
    print_queue.put(['Finishing up'])
    print_queue.join()


if __name__ == '__main__':
    run()