import logging

import google.auth.transport.requests
from google.oauth2.credentials import Credentials
from googleapiclient.discovery import build

from shared.secrets import get_gmail_oauth, save_gmail_tokens

logger = logging.getLogger(__name__)

_service = None

SCOPES = [
    "https://www.googleapis.com/auth/gmail.readonly",
    "https://www.googleapis.com/auth/calendar",
]


def get_calendar_service():
    global _service
    oauth = get_gmail_oauth()
    creds = Credentials(
        token=oauth.get("access_token"),
        refresh_token=oauth["refresh_token"],
        token_uri="https://oauth2.googleapis.com/token",
        client_id=oauth["client_id"],
        client_secret=oauth["client_secret"],
        scopes=SCOPES,
    )
    if not creds.valid:
        creds.refresh(google.auth.transport.requests.Request())
        save_gmail_tokens(
            creds.token,
            creds.expiry.isoformat() if creds.expiry else "",
        )
    _service = build("calendar", "v3", credentials=creds, cache_discovery=False)
    return _service


def list_events(service, time_min, time_max, max_results=10):
    result = (
        service.events()
        .list(
            calendarId="primary",
            timeMin=time_min,
            timeMax=time_max,
            maxResults=max_results,
            singleEvents=True,
            orderBy="startTime",
        )
        .execute()
    )
    return result.get("items", [])


def create_event(service, summary, start, end, attendees=None, description=None):
    body = {
        "summary": summary,
        "start": start,
        "end": end,
    }
    if description:
        body["description"] = description
    if attendees:
        body["attendees"] = [{"email": a} for a in attendees]
    return service.events().insert(calendarId="primary", body=body).execute()


def check_availability(service, time_min, time_max):
    body = {
        "timeMin": time_min,
        "timeMax": time_max,
        "items": [{"id": "primary"}],
    }
    result = service.freebusy().query(body=body).execute()
    return result["calendars"]["primary"]["busy"]