main.py

#!/usr/bin/env python
import sys
import os
from subprocess import call
from time import sleep
import argparse
#Welcome to pyLCI innards
#Here, things are about i and o, which are input and output
#And we output things for debugging, so o goes first.
from output import output

#These lines are here so that welcome message stays on the screen a little longer:
output.init()
o = output.screen
from ui import Printer, Menu

Printer(["Welcome to", "pyLCI"], None, o, 0)

try: #If there's an internal error, we show it on display and exit
    from apps.manager import AppManager
    #Now we init the input subsystem
    from input import input
    input.init()
    i = input.listener
except:
    Printer(["Oops. :(", "y u make mistake"], None, o, 0) #Yeah, that's about all the debug data. 
    raise


def exception_wrapper(callback):
    """This is a wrapper for all applications and menus. It catches exceptions and stops the system the right way when something bad happens, be that a Ctrl+c or an exception in one of the applications."""
    try:
        callback()
    except KeyboardInterrupt:
        Printer(["Does Ctrl+C", "hurt scripts?"], None, o, 0)
        i.atexit()
        sys.exit(1)
    except Exception as e:
        print(e)
        #raise
        Printer(["A wild exception", "appears!"], None, o, 0)
        i.atexit()
        sys.exit(1)
    else:
        Printer("Exiting pyLCI", None, o, 0)
        i.atexit()
        sys.exit(0)

def launch(name=None):
    """Function that launches pyLCI, either in full mode or single-app mode (if ``name`` kwarg is passed)."""
    app_man = AppManager("apps", Menu, Printer, i, o)
    if name != None:
        name = name.rstrip('/') #If using autocompletion from main folder, it might append a / at the name end, which isn't acceptable for load_app
        app = app_man.load_app(name)
        exception_wrapper(app.callback)
    else:
        app_menu = app_man.load_all_apps()
        exception_wrapper(app_menu.activate)

if __name__ == "__main__":
    parser = argparse.ArgumentParser(description="pyLCI runner")
    parser.add_argument('-a', '--app', action="store", help="Launch pyLCI with a single app loaded (useful for testing)", default=None)
    args = parser.parse_args()
    launch(name=args.app)