"""Construction et remise des emails.

`deliver_many` est le point d'injection unique (remplacé dans les tests)."""

import logging
import smtplib
import ssl
from collections.abc import Iterable
from email.message import EmailMessage

from app.config import get_settings

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


def build_message(to: str, subject: str, body: str) -> EmailMessage:
    message = EmailMessage()
    message["From"] = get_settings().smtp_from
    message["To"] = to
    message["Subject"] = subject
    message.set_content(body)
    return message


def deliver_many(messages: list[EmailMessage]) -> None:
    settings = get_settings()
    if not settings.email_enabled:
        # RGPD : ni destinataire ni corps dans les logs.
        logger.info(
            "Emails non envoyés (EMAIL_ENABLED=false) — %d message(s)",
            len(messages),
        )
        return
    if not messages:
        return

    context = ssl.create_default_context()
    if settings.smtp_ssl:
        client = smtplib.SMTP_SSL(
            settings.smtp_host, settings.smtp_port, timeout=30, context=context
        )
    else:
        client = smtplib.SMTP(
            settings.smtp_host, settings.smtp_port, timeout=30
        )
    with client as smtp:
        if settings.smtp_starttls and not settings.smtp_ssl:
            smtp.starttls(context=context)
        if settings.smtp_user:
            smtp.login(settings.smtp_user, settings.smtp_password)
        for message in messages:
            try:
                smtp.send_message(message)
            except smtplib.SMTPException:
                logger.warning("Échec d'envoi d'un email (destinataire masqué)")


def send(to: str, subject: str, body: str) -> None:
    deliver_many([build_message(to, subject, body)])


def send_many(items: Iterable[tuple[str, str, str]]) -> None:
    """`items` = itérable de `(destinataire, sujet, corps)`."""
    deliver_many([build_message(*item) for item in items])