reminders.py

#!/usr/bin/env python

"""
Trigger notifications for reminders.
"""

__author__  = "Daniel Souza <me@posix.dev.br>"

import os
import yaml
import subprocess
import datetime
from pathlib import Path
from dateutil.relativedelta import *

CONFIG_FILE = Path(os.getenv("XDG_CONFIG_HOME"), "reminders/config.yaml")
TODAY = datetime.date.today()

def load_config() -> dict:
    with open(CONFIG_FILE, 'r') as config:
        return yaml.safe_load(config)

def create_config() -> None:
    config_dir = os.path.dirname(CONFIG_FILE)
    if not os.path.exists(config_dir):
        os.makedirs(config_dir)

    reminders_file = Path(config_dir, "reminders.yaml")

    default_config = f'''
paths:
  - \"{reminders_file}"
    '''

    with open(CONFIG_FILE, 'w') as f:
        f.write(default_config)

    default_reminders = f'''
- name: "Example Reminder"\n
  desc: "This is an example. Edit configuration at {config_dir}."
  next: {TODAY.strftime("%Y-%m-%d")} 
  last:
  freq:
    '''

    with open(reminders_file, 'w') as f:
        f.write(default_reminders)

def read_reminders(file_path: str) -> list:
    with open(file_path, 'r') as file:
        reminders = yaml.safe_load(file)
    return reminders

def send_notification(summary: str, body: str) -> None:
    subprocess.run(['notify-send', summary, body])

def check_reminders(reminders: list) -> None:
    for reminder in reminders:
        if reminder.get('next'):
            next_date = reminder['next'] 
        elif reminder.get('last'):
            last_date = reminder['last']
            next_date = calc_next_date(last_date, reminder['freq'])
        else:
            continue

        if next_date <= TODAY:
            summary = reminder['name']
            if reminder.get('desc'):
                body = f"{reminder['desc']} [{next_date}]"
            else:
                body = str(next_date)
            send_notification(summary, body)

def calc_next_date(last_date: datetime, freq: str) -> datetime:
    freq_unit = freq[-1]
    freq_value = int(freq[0:-1])

    if freq_unit == "d":
        delta = relativedelta(days=+freq_value)
    elif freq_unit == "w":
        delta = relativedelta(weeks=+freq_value)
    elif freq_unit == "m":
        delta = relativedelta(months=+freq_value)
    elif freq_unit == "y":
        delta = relativedelta(years=+freq_value)

    next_date = last_date + delta
    return next_date

def main():
    if not os.path.isfile(CONFIG_FILE):
        create_config()

    config = load_config()

    for path in config['paths']:
        reminders = read_reminders(os.path.expanduser(path))
        check_reminders(reminders)

if __name__ == "__main__":
    main()