"""Tests for two-process terminal frontend"""

# Copyright (c) Jupyter Development Team.
# Distributed under the terms of the Modified BSD License.

import sys

from nose import SkipTest

from traitlets.tests.utils import check_help_all_output
from ipython_genutils.testing import decorators as dec

@dec.skip_win32
def test_console_starts():
    """test that `jupyter console` starts a terminal"""
    p, pexpect, t = start_console()
    p.sendline('5')
    idx = p.expect([r'Out\[\d+\]: 5', pexpect.EOF], timeout=t)
    idx = p.expect([r'In \[\d+\]', pexpect.EOF], timeout=t)
    stop_console(p, pexpect, t)

def test_help_output():
    """jupyter console --help-all works"""
    check_help_all_output('jupyter_console')

def test_display_text():
    "Ensure display protocol plain/text key is supported"
    # equivalent of:
    #
    #   x = %lsmagic
    #   from IPython.display import display; display(x);
    p, pexpect, t = start_console()
    p.sendline('x = %lsmagic')
    idx = p.expect([r'In \[\d+\]', pexpect.EOF], timeout=t)
    p.sendline('from IPython.display import display; display(x);')
    p.expect([r'Available line magics:', pexpect.EOF], timeout=t)
    stop_console(p, pexpect, t)

def stop_console(p, pexpect, t):
    "Stop a running `jupyter console` running via pexpect"
    # send ctrl-D;ctrl-D to exit
    p.sendeof()
    p.sendeof()
    p.expect([pexpect.EOF, pexpect.TIMEOUT], timeout=t)
    if p.isalive():
        p.terminate()


def start_console():
    "Start `jupyter console` using pexpect"
    import pexpect
    
    args = ['-m', 'jupyter_console', '--colors=NoColor']
    cmd = sys.executable
    
    try:
        p = pexpect.spawn(cmd, args=args)
    except IOError:
        raise SkipTest("Couldn't find command %s" % cmd)
    
    # timeout after one minute
    t = 60
    idx = p.expect([r'In \[\d+\]', pexpect.EOF], timeout=t)
    return p, pexpect, t
