"""
One-time OAuth authorization for Google Calendar access.
Run this ONCE to authorize Maya to access Google Calendar.
"""

import os
import sys
import json
from pathlib import Path

SCOPES = ['https://www.googleapis.com/auth/calendar']
CREDENTIALS_FILE = Path("credentials/google_oauth_credentials.json")
TOKEN_FILE       = Path("credentials/google_token.json")


def authorize():
    print("\n[LOCK] Google Calendar Authorization for Maya")
    print("=" * 50)

    if not CREDENTIALS_FILE.exists():
        print(f"\n[X] Credentials file not found: {CREDENTIALS_FILE}")
        sys.exit(1)

    from google_auth_oauthlib.flow import InstalledAppFlow
    from google.oauth2.credentials import Credentials
    from google.auth.transport.requests import Request

    creds = None

    # Check for existing valid token
    if TOKEN_FILE.exists():
        creds = Credentials.from_authorized_user_file(str(TOKEN_FILE), SCOPES)
        if creds and creds.valid:
            print("\n[OK] Already authorized! Token is valid.")
            _print_calendar_info(creds)
            return
        if creds and creds.expired and creds.refresh_token:
            print("\n[REFRESH] Token expired -- refreshing...")
            creds.refresh(Request())
            _save_token(creds)
            print("[OK] Token refreshed successfully.")
            return

    # Need fresh authorization
    print("\n[LIST] Starting OAuth authorization flow...")
    print("   This will open your browser.")
    print("   Log in with: rudybyte.code@gmail.com\n")

    flow = InstalledAppFlow.from_client_secrets_file(
        str(CREDENTIALS_FILE), SCOPES
    )

    try:
        # Use a specific port to match our redirect URI
        creds = flow.run_local_server(port=8090, open_browser=True)
    except Exception as e:
        print(f"\n[X] Error: {e}")
        print("\n[!] Try running this command in your local terminal manually if the browser doesn't open.")
        creds = flow.run_local_server(port=8090, open_browser=False)

    _save_token(creds)

    print("\n[OK] Authorization successful!")
    print(f"   Token saved to: {TOKEN_FILE}")
    print("\n   IMPORTANT: I will now save these to your .env file.")

    _print_calendar_info(creds)


def _save_token(creds):
    TOKEN_FILE.parent.mkdir(parents=True, exist_ok=True)
    with open(TOKEN_FILE, 'w') as f:
        f.write(creds.to_json())


def _print_calendar_info(creds):
    try:
        from googleapiclient.discovery import build
        service = build('calendar', 'v3', credentials=creds)
        cal = service.calendarList().get(calendarId='primary').execute()
        print(f"\n   [CAL] Calendar authorized for: {cal.get('summary', 'Unknown')}")
    except Exception as e:
        print(f"\n   (Could not fetch calendar info: {e})")


if __name__ == "__main__":
    authorize()