"""
utils/email.py — SMTP email helper.
Reads server settings from app_settings (email.smtp_*) with .env fallbacks.
"""

import logging
import smtplib
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
from config import get_setting

logger = logging.getLogger("utils.email")


def send_email(to, subject: str, body_text: str, body_html: str = None) -> None:
    """Send email via configured SMTP. `to` may be a str or list[str]. Raises on failure."""
    host   = get_setting("email.smtp_host", "").strip()
    port   = get_setting("email.smtp_port", "587").strip()
    user   = get_setting("email.smtp_user", "").strip()
    passwd = get_setting("email.smtp_password", "").strip()
    from_  = get_setting("email.smtp_from", "").strip() or user

    if not host:
        raise ValueError("SMTP host not configured. Add it via Admin → Settings.")

    try:
        port = int(port)
    except (ValueError, TypeError):
        port = 587

    recipients = [to] if isinstance(to, str) else list(to)
    if not recipients:
        raise ValueError("No recipients specified.")

    if body_html:
        msg = MIMEMultipart("alternative")
        msg.attach(MIMEText(body_text, "plain"))
        msg.attach(MIMEText(body_html, "html"))
    else:
        msg = MIMEText(body_text, "plain")

    msg["Subject"] = subject
    msg["From"]    = from_
    msg["To"]      = ", ".join(recipients)

    with smtplib.SMTP(host, port, timeout=15) as smtp:
        smtp.ehlo()
        try:
            smtp.starttls()
            smtp.ehlo()
        except smtplib.SMTPException:
            pass  # server may not support STARTTLS
        if user and passwd:
            smtp.login(user, passwd)
        smtp.sendmail(from_, recipients, msg.as_string())

    logger.info("Email sent to %s: %r", recipients, subject)