#!/usr/bin/python
#
# Ctrl-Z Test: Start a shell, run a program, 
#              send SIGTSTP, wait for status msg, move in 
#              foreground, then send SIGINT, then exit
#
# Requires use of the following commands:
#
#    ctrl-z control, fg, sleep
#

import sys, imp, atexit
sys.path.append("/home/courses/cs3214/software/pexpect-dpty/");
import pexpect, proc_check, shellio, signal, time, threading


#Ensure the shell process is terminated
def force_shell_termination(shell_process):
	c.close(force=True)

# pulling in the regular expression and other definitions
definitions_scriptname = sys.argv[1]
def_module = imp.load_source('', definitions_scriptname)
logfile = None
if hasattr(def_module, 'logfile'):
    logfile = def_module.logfile

# spawn an instance of the shell
c = pexpect.spawn(def_module.shell, drainpty=True, logfile=logfile)
atexit.register(force_shell_termination, shell_process=c)

# set timeout for all following 'expect*' calls to 2 seconds
c.timeout = 2

# ensure that shell prints expected prompt
assert c.expect(def_module.prompt) == 0, "Shell did not print expected prompt"



# run a command
c.sendline("sleep 60")

# The following call is necessary to ensure that the SIGTSTP
# we are sending below via 'sendcontrol' reaches the 'sleep' child.
# This is NOT a bullet-proof fix, you may fail on occasion!
time.sleep(1)


#checks the number of active child processes
#using a timeout based process count
proc_check.count_children_timeout(c, 1, 1)

#checks the number of active child processes
#at this moment in time
proc_check.count_active_children(c, 1)



# send SIGTSTP to 'sleep'
c.sendcontrol('z')

# shell should pick up that 'sleep' was stopped and respond with job status
# it should output a line such [6]+  Stopped                 sleep 60
(jobid, statusmsg, cmdline) = \
        shellio.parse_regular_expression(c, def_module.job_status_regex)
assert statusmsg == def_module.jobs_status_msg['stopped'], "Shell did not report stopped job"

# move job into foreground
c.sendline(def_module.builtin_commands['fg'] % jobid)

# when moving a job in the foreground, bash outputs its command line
assert c.expect_exact(cmdline) == 0, "Shell did not move job in foreground"



# send SIGINT
c.sendintr()

#check that the prompt prints
assert c.expect(def_module.prompt) == 0, "Shell did not print expected prompt"



#exit
c.sendline("exit")
assert c.expect_exact("exit\r\n") == 0, "Shell output extraneous characters"

shellio.success()