"""Anwendungseinstellungen."""

from fastapi import APIRouter

from app.api.deps import DbSession
from app.core.clock import period_bounds, period_key, today
from app.schemas.settings import AppSettingsIn, AppSettingsOut
from app.services.settings import load_settings, save_settings

router = APIRouter(prefix="/settings", tags=["settings"])


def _out(month_start_day: int) -> AppSettingsOut:
    schluessel = period_key(today(), month_start_day)
    beginn, ende = period_bounds(schluessel, month_start_day)
    return AppSettingsOut(
        month_start_day=month_start_day,
        current_month=schluessel,
        current_period_start=beginn,
        current_period_end=ende,
    )


@router.get(
    "",
    response_model=AppSettingsOut,
    summary="Einstellungen lesen",
    description="Liefert den eingestellten Monatsbeginn und den daraus folgenden "
    "laufenden Abrechnungsmonat.",
)
async def read_settings(session: DbSession) -> AppSettingsOut:
    return _out((await load_settings(session)).month_start_day)


@router.put(
    "",
    response_model=AppSettingsOut,
    summary="Einstellungen ändern",
    description="Ein geänderter Monatsbeginn wirkt sofort auf Dashboard, Kalender, "
    "Budgets, Vorschau und Export.",
)
async def update_settings(session: DbSession, payload: AppSettingsIn) -> AppSettingsOut:
    eintrag = await save_settings(session, month_start_day=payload.month_start_day)
    await session.commit()
    return _out(eintrag.month_start_day)