io.py

# -*- coding: utf-8 -*-
import getpass
import time
import sys
import thread


def preloaderPause(fn, *args, **kwargs):
    def wrapped():

        if not preloader.isLaunch:
            return fn(*args, **kwargs)

        preloader.stop()
        result = fn(*args, **kwargs)
        preloader.launch()

        return result
    
    return wrapped


class preloader(object):

    #progress = "\|/-"
    progress = (">  ", ">> ", ">>>", " >>", "  >", "   ")
    clearLine = "\r"+" "*40+"\r"
    message = None
    isLaunch = False
    counter = 0

    @staticmethod
    def setMessage(message, needLaunch=True):
        preloader.message = message
        if not preloader.isLaunch and needLaunch:
            preloader.launch()

    @staticmethod
    def launch():
        preloader.counter = 0
        preloader.isLaunch = True
        thread.start_new_thread(preloader.draw, ())

    @staticmethod
    def stop():
        preloader.counter = -1
        preloader.draw()
        preloader.isLaunch = False

    @staticmethod
    def draw():
        if not preloader.isLaunch:
            return

        sys.stdout.write(preloader.clearLine)
        if preloader.counter == -1:
            sys.stdout.flush()
            return

        preloader.counter += 1
        sys.stdout.write("%s : %s" % (preloader.progress[preloader.counter % len(preloader.progress)], preloader.message))
        sys.stdout.flush()

        time.sleep(0.3)
        preloader.draw()

@preloaderPause
def GetUserCredentials():
    """Prompts the user for a username and password."""
    
    email = None
    password = None
    if email is None:
        email = raw_input("Email: ")
        
    if password is None:
        password = getpass.getpass("Password for %s: " % email)
    
    return (email, password)