#!/usr/bin/env python3
# stolat, cron-based birthday notifier
# Please run once per day.
# License: GPLv3 or later
import toml, os, importlib
from datetime import datetime

scripts = []

def get_current_path() -> str:
	return os.path.dirname(os.path.abspath(__file__))

def load_config() -> dict:

	# Try to get configuration from current_path/list.toml
	try:
		path   = get_current_path()
		config = toml.load(path + "/list.toml")
	except:
		print("Sorry! It seems like I can't access list.toml. Is it in the script's working directory?")
		quit(-1)

	return config

def calc_age(birth_date: str) -> int:
	date_as_datetime = datetime.strptime(birth_date, "%Y-%m-%d")
	delta = datetime.today() - date_as_datetime
	return round(delta.days / 365.25)

def notify_user(birthday: dict, user: dict, actions: dict, days_till_birthday: int):
	# print(f"Got {birthday}, {user} and actions {actions}.")
	for channel in user['channels']:

		for notify_action in actions:

			if notify_action['id'] == channel:

				# User wants to receive a notification through current notify_action
				try:
					module = importlib.import_module("scripts." + notify_action['name_of_script'][:notify_action['name_of_script'].rfind(".py")])
					func   = getattr(module, notify_action['startup_function'])
					func("v1", user['user'], birthday['name'], calc_age(birthday['date']), days_till_birthday, birthday['date']) # v1-formatted function call
				except Exception as e:
					print(f"Error: failed executing {notify_action['startup_function']}() for {user['user']} ({birthday['name']}'s {calc_age(birthday['date'])}th birthday) :(\n"
					      f"Exception: {e}.")

def iterate_birthdays(config: dict):

	badly_formatted_birthdays = 0
	today = datetime.today()
	for birthday in config['birthdays']:

		try:
			name             = birthday['name']
			birthdate_as_str = birthday['date']
			birthdate        = datetime.strptime(birthdate_as_str, "%Y-%m-%d")
			to_notify        = birthday['to_notify']
		except Exception as e:
			badly_formatted_birthdays += 1
			continue

		for user in config['preferences']:

			birthdate_this_year = birthdate.replace(year=today.year)

			# Safeguard against no additional reminders
			if not user['additional_reminders']:
				user['additional_reminders'] = []

			# Consider the birthday as additional reminder
			# This way we check the list once.
			if (birthdate_this_year - today).days + 1 in user['additional_reminders']:
				notify_user(birthday, user, config['actions'], (birthdate_this_year - today).days + 1)

	if badly_formatted_birthdays > 0:
		print(f"Warning: found {badly_formatted_birthdays} incorrectly formatted birth dates.\n"
		      f"         They haven't been checked for possible birthdays. Please use ISO 8601.")



def main():
	config = load_config()
	iterate_birthdays(config)

if __name__ == "__main__":
	main()