import sys, os, shutil, filecmp, string, datetime, time

# initalize some variables
cronPeriod = 1
sleepFile = "/Library/Preferences/SystemConfiguration/com.apple.PowerManagement.plist"
saverFile = os.path.join(os.getenv("HOME")) + '/Library/Preferences/ByHost/com.apple.screensaver.0016cb98e9e2'
trackingFile = os.path.join(os.getenv("HOME")) + '/var/sleepTracker'

f = open(sleepFile, "r")
useNextLine = 0
for line in f.readlines():
  if useNextLine == 1:
    useNextLine = 0
    timeLine = line.strip()
  if line.strip() == "<key>System Sleep Timer</key>":
    useNextLine = 1
f.close()

sleepTime = timeLine.strip('<integer>')
sleepTime = sleepTime.strip('</')
sleeepTime = int(sleepTime)

screensaverTime = os.popen("defaults read " + saverFile + " idleTime")
screensaverTime =  screensaverTime.read()

sleepTime = int(sleepTime) * 60 - int(screensaverTime)
if sleepTime < 0:
  sleepTime = 0


########################################
# Begin function definations
######################################## 
# checkFiles is the function that checks the times
# of the tracking file

def clearFile():
  if os.path.exists(trackingFile):
    os.remove(trackingFile)
  cmd = "touch " + trackingFile
  os.system(cmd)

def compareTimes():
  endLine = ""
  currentTime = time.mktime(datetime.datetime.now().timetuple())
  currentTime = str(currentTime).split('.')[0]

  f = open(trackingFile, "r")
  data = f.read()
  f.close()
  lines = data.split("n")
  lastRunning = lines[len(lines)-2]
  lastRunning = lastRunning.split('.')[0]

  if lastRunning == "":
    print "last time is: " + lastRunning
    return

  difference = int(currentTime) - int(lastRunning)
  print time.localtime()
  print "difference between current time and last time saver was found running is: ", difference
 
  cronPeriodSec = int(cronPeriod * 1.5 * 60)
  print time.localtime()
  print "cron period is: ", cronPeriodSec

  if difference > cronPeriodSec:
    print time.localtime()
    print "difference is greater - need to clear file"
    clearFile()

def wantSleep(currentTime):
  f = open(trackingFile, "r")
  data = f.read()
  f.close()
  lines = data.split("n")
  firstRunning = lines[0]
  firstRunning = firstRunning.split('.')[0]

  if firstRunning == "":
    #print "firstRunning was blank"
    return

  print "current time is: ", currentTime, " first time is: ", firstRunning
  difference = int(currentTime) - int(firstRunning)
  print time.localtime()
  print "difference between now and first time screensaver was on is: ", difference
  print "comparing against: ", int(sleepTime) 

  if difference >= sleepTime:
    print time.localtime()
    print "sleep is desired" 
    aplcmd = 'tell app "Finder" to sleep'
    cmd = "/usr/bin/osascript -e " + "'" + aplcmd + "'"
    print time.localtime()
    print cmd
    os.system(cmd)
 
##############################################
# End function definations
#############################################

#check if the screensaver is running:
cmd = "ps -e | grep ScreenSaverEngine | grep -v grep"
result = os.system(cmd)

#print "remove the following line to run for real"
#result = 234

if result != 256:
  print time.localtime()
  print "Screen Saver is running"
  compareTimes()

  currentTime = time.mktime(datetime.datetime.now().timetuple())
  currentTime = str(currentTime).split('.')[0]
  f = open(trackingFile, 'a')
  f.write(currentTime + "n")
  f.close

  wantSleep(currentTime)

else:
  print time.localtime()
  print "Screen Saver Not running"
  clearFile()

sys.exit(1)