import datetime
import os.path

from google.auth.transport.requests import Request
from google.oauth2.credentials import Credentials
from google_auth_oauthlib.flow import InstalledAppFlow
from googleapiclient.discovery import build
from googleapiclient.errors import HttpError

# If modifying these scopes, delete the file token.json.
SCOPES = ["https://www.googleapis.com/auth/calendar.readonly"]


def get_next_ten():
    """Shows basic usage of the Google Calendar API.
    Prints the start and name of the next 10 events on the user's calendar.
    """
    creds = None
    # The file token.json stores the user's access and refresh tokens, and is
    # created automatically when the authorization flow completes for the first
    # time.
    if os.path.exists("token.json"):
      creds = Credentials.from_authorized_user_file("token.json", SCOPES)
    # If there are no (valid) credentials available, let the user log in.
    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.json", SCOPES
                )
        creds = flow.run_local_server(port=0)
    # Save the credentials for the next run
    with open("token.json", "w") as token:
        token.write(creds.to_json())

    try:
        service = build("calendar", "v3", credentials=creds)

        # Call the Calendar API
        now = datetime.datetime.now(tz=datetime.timezone.utc).isoformat()
        print("Getting the upcoming 10 events")
        events_result = (
                service.events()
                .list(
                    calendarId="primary",
                    timeMin=now,
                    maxResults=10,
                    singleEvents=True,
                    orderBy="startTime",
                    )
                .execute()
                )
        events = events_result.get("items", [])

        if not events:
            print("No upcoming events found.")
            return

        # Prints the start and name of the next 10 eventsa
        next_ten = []
        for event in events:
            is_datetime = event["start"].get("dateTime") is not None
            if is_datetime:
                event_start = datetime.datetime.fromisoformat(event["start"].get("dateTime", event["start"].get("date")))
                event_end = datetime.datetime.fromisoformat(event["end"].get("dateTime", event["end"].get("date")))
                formatted_start_time = event_start.strftime("%Y-%m-%d %H:%M")
                formatted_end_time = event_end.strftime("%H:%M")
                formatted_event_time = f"{formatted_start_time} to {formatted_end_time}"
            else:
                formatted_event_time = event["start"].get("date")
            next_ten.append(f"{formatted_event_time}: {event['summary']}")
            print(formatted_event_time, event["summary"])

        return next_ten

    except HttpError as error:
        print(f"An error occurred: {error}")


if __name__ == "__main__":
    get_next_ten()