"""Short emails about reopen requests, sent through the configured account when email is on.

Best effort: a failure is written to the mail log and never blocks the action itself.
"""
from sqlalchemy import select
from sqlalchemy.orm import Session

from . import mailer
from .models import BudgetYear, MailSettings, User


def _ready(db: Session) -> MailSettings | None:
    cfg = db.get(MailSettings, 1)
    return cfg if cfg and mailer.is_ready(cfg) else None


def reopeners(db: Session, budget: BudgetYear) -> list[User]:
    """Who can reopen the budget: administrators and the department's approvers."""
    users = db.scalars(select(User).where(User.active)).all()
    return [u for u in users if u.role == "admin" or (u.role == "approver" and u.department_id == budget.department_id)]


def send(db: Session, actor: User, budget: BudgetYear, to: list[User], subject: str, body: str) -> None:
    cfg = _ready(db)
    addresses = sorted({u.email for u in to if u.email and u.id != actor.id})
    if not cfg or not addresses:
        return
    try:
        addresses = mailer.clean_addresses(addresses)
    except mailer.MailError:
        return
    mailer.send(db, actor, cfg, to=addresses, cc=[], subject=subject, body=body, attachments=[], kind="notice",
                year_id=budget.id, context=f"{budget.department.name} {budget.year}")