import logging
from django.conf import settings
from django.core.mail import EmailMultiAlternatives
from django.template.loader import render_to_string

logger = logging.getLogger(__name__)


def send_email(template_name: str, context: dict, subject: str, to: str | list[str]) -> bool:
    """
    Render and send an HTML email with plaintext fallback.
    Returns True on success, False on failure.
    """
    if isinstance(to, str):
        to = [to]

    html = render_to_string(f'emails/{template_name}.html', context)
    text = render_to_string(f'emails/{template_name}.txt', context)

    msg = EmailMultiAlternatives(
        subject=subject,
        body=text,
        from_email=settings.DEFAULT_FROM_EMAIL,
        to=to,
    )
    msg.attach_alternative(html, 'text/html')

    try:
        msg.send()
        return True
    except Exception:
        logger.exception('Failed to send email "%s" to %s', template_name, to)
        return False