import os
import datetime
from collections import deque

# open numbered log files and evaluate the results
# the log files have been copied from the server to this directory
# the log files are named log-NSWMessageService.txt.0, log-NSWMessageService.txt.1, log-NSWMessageService.txt.2, ...
# for the first analysis I have copied 10 log files to this directory but placed them in the .gitignore file

# get the current working directory

abspath = os.path.abspath(__file__)
dname = os.path.dirname(abspath)

outputFileName = dname + "\\" + 'output.csv'

# open the output file
outputFile = open(outputFileName, 'w')

# write the header

outputFile.write('Receive time, Duration\n')

# open the log files

q = deque()

for i in range(0, 10):
    logFileName = dname + "\\" + 'log-NSWMessageService.txt.' + str(i)
    logFile = open(logFileName, 'r')

    # read the content line by line
    while True:
        line = logFile.readline()
        if not line:
            break

        # get substring of the date
        dateString = line[0:19]

        if "Upload of" in line:
            # add the dateString to the queue
            q.appendleft(dateString)

        elif "Download of" in line:
            # find the corresponding dateString in the queue
            # calculate the duration
            # remove the dateString from the queue
            lastdatestring = q.pop()

            # create date from string
            lastdate = datetime.datetime.strptime(lastdatestring, '%Y-%m-%d %H:%M:%S')
            currentdate = datetime.datetime.strptime(dateString, '%Y-%m-%d %H:%M:%S')

            # calculate the duration
            duration = currentdate - lastdate
            outputFile.write(dateString + "," + str(duration.seconds) + "\n")

    # close the log file
    logFile.close()

outputFile.close()