###########
# Imports #
###########

from splinter import Browser

from splinter import exceptions

import sys


#############
# Functions #
#############

class Facebook(object):

    def __init__(self, link_address, email, password):
        self.exists = None
        self.link_address = link_address
        self.signed_in = False
        self.browser = None
        self.connections = None
        self.email = email
        self.password = password

    def does_url_exist(self):
        """ Checks if url exists, stores the Browser() session in self.browser for continuity.

        Returns:
            url_exists: True or False
        Args:
            url: url of the site to test
        Raises:
            None
        Usage:
            url_exists = does_url_exist(url)

        """
        browser = Browser()
        try:
            browser.visit(self.link_address)
            self.exists=True
            self.browser = browser
        except:
            self.exists=False
            browser.quit()
            raise Exception("the linkedin URL does not exist: "+self.link_address)

    def sign_in(self):
        """ signs into Facebook, stores Browser() session into self.browser for continuity.

        Returns:
            None
        Args:
            None
        Raises:
            None
        Usage:
            self.sign_in()

        """

        if self.exists:

            print "signing in to facebook..."

            browser = self.browser

            browser.fill("email",self.email) # e.g.:self.email:"james1029394756@hotmail.com"

            browser.fill("pass",self.password) # e.g.:self.password:"*********"

            browser.driver.find_element_by_id("u_0_l").click() # clicks the "login" button

            self.signed_in = True

            self.browser = browser

        else:

            print "checking if URL exists..."

            self.does_url_exist()

            self.sign_in()

    def say_happy_birthday(self):

        """ iteratively post "Happy Birthday!" to all friends whose birthday it is

        Returns:
            None
        Args:
            None
        Raises:
            None
        Usage:
            self.say_happy_birthday()

        """

        if self.signed_in:

            browser = self.browser

            print "celebrating birthdays..."

            # Click "events"
            browser.find_link_by_partial_text("Events").click()

            # Expand birthdays
            browser.find_link_by_partial_href("/events/birthdays/?acontext")[0].click()

            # Say happy birthday to everyone until there are no more birthdays
            while True:

                try:

                    print "\tsaying happy birthday!"

                    browser.fill("message_text","Happy Birthday!\r")

                except exceptions.ElementDoesNotExist:

                    print "\tno more birthdays to celebrate!"

                    break

            self.browser = browser

        else:

            self.sign_in()

            self.say_happy_birthday()


    def quit(self):

        """ closes the browser

        Args:
            None
        Returns:
            None
        Raises:
            None
        E.g.:Usage:
            self.quit()

        """

        browser = self.browser

        browser.quit()

########
# Main #
########


platform     =  "facebook" # @changeme

help_message = "Usage: python ./"+platform+" <"+platform+" email address> <linkedin password>"

url          = "https://www.facebook.com" # @changeme


# Is the script run from within python?
#   YES:
if len(sys.argv)==1:
    email   = raw_input("type your "+platform+" email (e.g. some@email.com)...")
    password= raw_input("type your "+platform+" password (e.g. *********)...")
else:
#   NO:
    try:
        email = sys.argv[1]         # e.g.:james1029384756@hotmail.com
    except IndexError:
        raise Exception(help_message)
    try:
        password = sys.argv[2]      # e.g.:*********
    except IndexError:
        raise Exception(help_message)


session = Facebook(url,email,password)

session.sign_in()

session.say_happy_birthday()

session.quit()