"""
Google Calendar API integration.
Reads today's events and upcoming schedule.
"""
import datetime
from googleapiclient.discovery import build
from core.google_auth import get_credentials

def _service():
    return build('calendar', 'v3', credentials=get_credentials())

def get_todays_events() -> list[dict]:
    """Return all events happening today."""
    now = datetime.datetime.now(tz=datetime.timezone.utc)
    end = now.replace(hour=23, minute=59, second=59)
    result = _service().events().list(
        calendarId='primary',
        timeMin=now.isoformat(),
        timeMax=end.isoformat(),
        singleEvents=True,
        orderBy='startTime'
    ).execute()
    return [
        {
            'summary': e.get('summary', '(No title)'),
            'start': e['start'].get('dateTime', e['start'].get('date')),
            'end': e['end'].get('dateTime', e['end'].get('date')),
            'location': e.get('location', ''),
        }
        for e in result.get('items', [])
    ]

def get_upcoming_events(days: int = 7) -> list[dict]:
    """Return events in the next N days."""
    now = datetime.datetime.now(tz=datetime.timezone.utc)
    end = now + datetime.timedelta(days=days)
    result = _service().events().list(
        calendarId='primary',
        timeMin=now.isoformat(),
        timeMax=end.isoformat(),
        maxResults=20,
        singleEvents=True,
        orderBy='startTime'
    ).execute()
    return [
        {
            'summary': e.get('summary', '(No title)'),
            'start': e['start'].get('dateTime', e['start'].get('date')),
        }
        for e in result.get('items', [])
    ]

def create_event(summary: str, start_dt: str, end_dt: str, description: str = "") -> dict:
    """Create a new calendar event. Dates in ISO 8601 format."""
    event = {
        'summary': summary,
        'description': description,
        'start': {'dateTime': start_dt, 'timeZone': 'America/Chicago'},
        'end': {'dateTime': end_dt, 'timeZone': 'America/Chicago'},
    }
    return _service().events().insert(calendarId='primary', body=event).execute()