from os import listdir
from sys import argv
from multiprocessing.pool import ThreadPool
import multiprocessing
import time
import collections, functools, operator


def process_file(name):
    counts = {'A': 0, 'C': 0, 'G': 0, 'T': 0}
    with open(name) as f:
        for line in f:
            for index in line:
                if index.upper() in counts:
                    counts[index.upper()] += 1
    return counts


dir_path = "influenza/"  # Assumes trailing '/'.
try:
    filenames = listdir(dir_path)
    start_time = time.time()
except FileNotFoundError:
    print("No such directory found.")
    quit()

numthreads = 8
pool = multiprocessing.Pool(processes=numthreads)

result_list = pool.map(process_file,
        (dir_path+filename for filename in filenames ) )

result = dict(functools.reduce(operator.add,
         map(collections.Counter, result_list)))

print(result)


print("--- %s seconds ---" % (time.time() - start_time))