main.py

import datetime
import os
import pickle
import serial.tools.list_ports
import serial
import time
import dateutil.parser
from google.auth.transport.requests import Request
from google_auth_oauthlib.flow import InstalledAppFlow
from googleapiclient.discovery import build

# Define the scopes and credentials file path
SCOPES = ['https://www.googleapis.com/auth/calendar.readonly']
CREDENTIALS_FILE = 'cred.json'
TOKEN_FILE = 'token.pickle'

def authenticate():
    creds = None
    if os.path.exists(TOKEN_FILE):
        with open(TOKEN_FILE, 'rb') as token:
            creds = pickle.load(token)
    if not creds or not creds.valid:
        if creds and creds.expired and creds.refresh_token:
            creds.refresh(Request())
        else:
            flow = InstalledAppFlow.from_client_secrets_file(CREDENTIALS_FILE, SCOPES)
            creds = flow.run_local_server(port=0)
        with open(TOKEN_FILE, 'wb') as token:
            pickle.dump(creds, token)
    return creds

def get_next_event(service):
    now = datetime.datetime.utcnow()
    end_of_week = now + datetime.timedelta(days=2)

    events_result = service.events().list(calendarId='primary', timeMin=now.isoformat() + 'Z',
                                      timeMax=end_of_week.isoformat() + 'Z',
                                      maxResults=1, singleEvents=True,
                                      orderBy='startTime').execute()
    events = events_result.get('items', [])
    if not events:
        return False, None, None, None
    else:
        event = events[0]
        start = event['start'].get('dateTime', event['start'].get('date'))
        end = event['end'].get('dateTime', event['end'].get('date'))

        start_time = dateutil.parser.parse(start)
        end_time = dateutil.parser.parse(end)

        formatted_start = start_time.strftime('%a %H:%M')
        formatted_end = end_time.strftime('%H:%M')

        summary = event['summary']
        # summary = "1234567890abcdefghijklmnopqrstuvwxyz" # for debugging
        if len(summary) > 16:
            summary = summary[:13] + '...'

        return True, summary, formatted_start, formatted_end

def findport():
    ports = serial.tools.list_ports.comports()
    portsList = []

    for i in ports: # make a list of ports
        portsList.append(str(i))
    print('Found ports: {}'.format(portsList))

    if not portsList: # if no ports are available
        print("No ports available")
        return None

    port = input("Enter port name: ") # ask user for port name
    return port

def output(portVar, summary, start, end):
    screen = serial.Serial(portVar, 9600)
    time.sleep(2)
    display_text = f"{start}-{end}\n{summary}\n"

    if screen.is_open:
        screen.write(display_text.encode())

    screen.close()

def main():
    creds = authenticate()
    service = build('calendar', 'v3', credentials=creds)
    portVar = findport()
    
    while True:
        boole, summary, start, end = get_next_event(service)
        if boole:
            output(portVar, summary, start, end)
        else:
            output(portVar, "No upcoming events", "", "")
        print("Updated")
        time.sleep(1 * 60) # Delay for 1 minute
        print("Updating...")


if __name__ == '__main__':
    main()