import threading
import time
import random

class Ticker:
    def __init__ (self):
        self.currentTick = 0
        self.functionStatus = {}

    def beginNextTick(self):
        for k, val in self.functionStatus.items():
            val.clear()
            val.wait()
        self.currentTick += 1
        return self.currentTick

    def isDone (self, funcId):
        self.functionStatus[funcId].set()

    def registerFunction (self, funcId):
        self.functionStatus[funcId] = threading.Event()

    def waitForNewTick (self):
        for k, val in self.functionStatus.items():
            val.wait()

    def getCurrentTick (self):
        return self.currentTick

    def track (self, numTicks):
        while self.beginNextTick() < numTicks:
            pass


def printDog(ticker, funcId):
    global dogRunning

    while dogRunning:
        print(ticker.getCurrentTick(), funcId)
        ticker.isDone (funcId)
        ticker.waitForNewTick ()

def printCat(ticker, funcId):
    global catRunning

    while catRunning:
        print(ticker.getCurrentTick(), funcId)
        ticker.isDone (funcId)
        ticker.waitForNewTick ()


def startFunctionThreads(ticker):
    tArr = []
    for func in [printDog, printCat]:
        ticker.registerFunction(func.__name__)
        t = threading.Thread (target=func, args=(ticker, func.__name__))
        t.start()
        tArr.append (t)

    return tArr


if __name__ == "__main__":

    dogRunning = True
    catRunning = True

    ticker = Ticker()
    tArr = startFunctionThreads (ticker)

    numTicks = 5000
    ticker.track(numTicks)

    dogRunning = False
    catRunning = False

    for t in tArr:
        t.join()