"""
Gmail API integration — read-only access.
Fetches unread messages and supports search queries.
"""
from googleapiclient.discovery import build
from core.google_auth import get_credentials

def _service():
    return build('gmail', 'v1', credentials=get_credentials())

def get_unread_emails(count: int = 10) -> list[dict]:
    """Fetch the most recent unread emails."""
    svc = _service()
    result = svc.users().messages().list(
        userId='me', q='is:unread', maxResults=count
    ).execute()
    messages = result.get('messages', [])
    emails = []
    for msg in messages:
        detail = svc.users().messages().get(
            userId='me', id=msg['id'], format='metadata',
            metadataHeaders=['Subject', 'From', 'Date']
        ).execute()
        headers = {h['name']: h['value'] for h in detail['payload']['headers']}
        emails.append({
            'id': msg['id'],
            'subject': headers.get('Subject', '(No subject)'),
            'from': headers.get('From', ''),
            'date': headers.get('Date', ''),
            'snippet': detail.get('snippet', ''),
        })
    return emails

def search_emails(query: str, count: int = 20) -> list[dict]:
    """Search Gmail using standard Gmail search syntax."""
    svc = _service()
    result = svc.users().messages().list(
        userId='me', q=query, maxResults=count
    ).execute()
    messages = result.get('messages', [])
    emails = []
    for msg in messages:
        detail = svc.users().messages().get(
            userId='me', id=msg['id'], format='metadata',
            metadataHeaders=['Subject', 'From', 'Date']
        ).execute()
        headers = {h['name']: h['value'] for h in detail['payload']['headers']}
        emails.append({
            'id': msg['id'],
            'subject': headers.get('Subject', '(No subject)'),
            'from': headers.get('From', ''),
            'snippet': detail.get('snippet', ''),
        })
    return emails