#!/usr/bin/env python
import random
import datetime
import time
import sys
import pathlib


def as_millis(s):
    return s*1000


def take_sample():
    waittime = random.randint(0,5)
    time.sleep(waittime)
    start=datetime.datetime.now()
    sys.stderr.write("GO")
    sys.stderr.flush()
    input()
    end=datetime.datetime.now()
    delta = end - start
    return as_millis(delta.total_seconds())


def record_metric(avg, log: pathlib.Path):
    now = datetime.datetime.now()
    with log.open('a+', encoding='utf-8') as f:
        f.write(f"{now}\t{avg}\n")
        f.flush()


if __name__ == "__main__":
    samples = []
    n = 5
    print("Press Enter when you see GO")
    for i in range(0, n):
        samples.append(take_sample())
    avg = sum(samples)/n
    record_metric(avg, pathlib.Path("~/org/reactiontime.log").expanduser())
    print(avg)