"""Direct Google Calendar and Gmail tools using google-api-python-client."""
import json
import boto3
from strands import tool
from google.oauth2.credentials import Credentials
from google.auth.transport.requests import Request
from googleapiclient.discovery import build
from datetime import datetime, timezone, timedelta

_sm = None


def _secrets():
    global _sm
    if _sm is None:
        _sm = boto3.client('secretsmanager', region_name='us-east-1')
    return _sm


def _get_creds(actor_id: str) -> Credentials:
    secret_name = 'agent-claw/google-credentials/' + actor_id.replace(':', '-')
    resp = _secrets().get_secret_value(SecretId=secret_name)
    data = json.loads(resp['SecretString'])

    # Load OAuth client info
    client_resp = _secrets().get_secret_value(SecretId='agent-claw/google-oauth-client')
    client = json.loads(client_resp['SecretString'])

    creds = Credentials(
        token=data.get('token'),
        refresh_token=data.get('refresh_token'),
        token_uri=data.get('token_uri', 'https://oauth2.googleapis.com/token'),
        client_id=client.get('client_id'),
        client_secret=client.get('client_secret'),
        scopes=data.get('scopes'),
    )

    if creds.expired and creds.refresh_token:
        creds.refresh(Request())
        # Persist refreshed token
        data['token'] = creds.token
        _secrets().put_secret_value(SecretId=secret_name, SecretString=json.dumps(data))

    return creds


def _actor_id():
    # Import here to avoid circular import; set per-invocation in main.py
    import main as _main
    return _main._current_actor_id


@tool
def list_calendars() -> str:
    """List all Google Calendars for the current user."""
    try:
        creds = _get_creds(_actor_id())
        svc = build('calendar', 'v3', credentials=creds)
        result = svc.calendarList().list().execute()
        items = result.get('items', [])
        if not items:
            return 'No calendars found.'
        return '\n'.join(f"{c['id']}: {c['summary']}" for c in items)
    except Exception as e:
        return f'Error listing calendars: {e}'


@tool
def get_calendar_events(calendar_id: str = 'primary', days_ahead: int = 7) -> str:
    """Get upcoming Google Calendar events.

    Args:
        calendar_id: Calendar ID (default: 'primary')
        days_ahead: Number of days ahead to fetch (default: 7)
    """
    try:
        creds = _get_creds(_actor_id())
        svc = build('calendar', 'v3', credentials=creds)
        now = datetime.now(timezone.utc)
        time_max = now + timedelta(days=days_ahead)
        result = svc.events().list(
            calendarId=calendar_id,
            timeMin=now.isoformat(),
            timeMax=time_max.isoformat(),
            singleEvents=True,
            orderBy='startTime',
            maxResults=50,
        ).execute()
        events = result.get('items', [])
        if not events:
            return 'No upcoming events.'
        lines = []
        for e in events:
            start = e['start'].get('dateTime', e['start'].get('date', ''))
            lines.append(f"{start} — {e.get('summary', '(no title)')}")
        return '\n'.join(lines)
    except Exception as e:
        return f'Error fetching calendar events: {e}'


@tool
def list_gmail_messages(max_results: int = 10, query: str = 'in:inbox') -> str:
    """List Gmail messages.

    Args:
        max_results: Maximum number of messages to return (default: 10)
        query: Gmail search query (default: 'in:inbox')
    """
    try:
        creds = _get_creds(_actor_id())
        svc = build('gmail', 'v1', credentials=creds)
        result = svc.users().messages().list(
            userId='me', q=query, maxResults=max_results
        ).execute()
        messages = result.get('messages', [])
        if not messages:
            return 'No messages found.'
        lines = []
        for m in messages:
            msg = svc.users().messages().get(
                userId='me', id=m['id'], format='metadata',
                metadataHeaders=['Subject', 'From', 'Date']
            ).execute()
            headers = {h['name']: h['value'] for h in msg.get('payload', {}).get('headers', [])}
            lines.append(
                f"id={m['id']} | {headers.get('Date', '')} | From: {headers.get('From', '')} | {headers.get('Subject', '(no subject)')}"
            )
        return '\n'.join(lines)
    except Exception as e:
        return f'Error listing Gmail messages: {e}'


@tool
def get_gmail_message(message_id: str) -> str:
    """Get the full content of a Gmail message by ID.

    Args:
        message_id: The Gmail message ID
    """
    try:
        creds = _get_creds(_actor_id())
        svc = build('gmail', 'v1', credentials=creds)
        msg = svc.users().messages().get(
            userId='me', id=message_id, format='full'
        ).execute()
        headers = {h['name']: h['value'] for h in msg.get('payload', {}).get('headers', [])}
        body = _extract_body(msg.get('payload', {}))
        return (
            f"From: {headers.get('From', '')}\n"
            f"To: {headers.get('To', '')}\n"
            f"Date: {headers.get('Date', '')}\n"
            f"Subject: {headers.get('Subject', '')}\n\n"
            f"{body}"
        )
    except Exception as e:
        return f'Error fetching Gmail message: {e}'


def _extract_body(payload: dict) -> str:
    import base64
    mime = payload.get('mimeType', '')
    if mime == 'text/plain':
        data = payload.get('body', {}).get('data', '')
        return base64.urlsafe_b64decode(data + '==').decode('utf-8', errors='replace') if data else ''
    for part in payload.get('parts', []):
        text = _extract_body(part)
        if text:
            return text
    return ''