from fastapi import APIRouter, Depends
from sqlalchemy.orm import Session

from ..config import get_settings
from ..database import get_db
from ..deps import get_current_user, require_admin
from ..models import Setting, User
from ..schemas import SettingOut

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

EXPIRY_WARNING_KEY = "expiry_warning_days"
# Ab wie viel Prozent Übereinstimmung ein Artikel beim Kassenzettel-Scan als
# Treffer vorgeschlagen wird.
RECEIPT_THRESHOLD_KEY = "receipt_match_threshold"
RECEIPT_THRESHOLD_DEFAULT = 45


def get_expiry_warning_days(db: Session) -> int:
    row = db.get(Setting, EXPIRY_WARNING_KEY)
    if row is None:
        return get_settings().expiry_warning_days_default
    try:
        return int(row.value)
    except ValueError:
        return get_settings().expiry_warning_days_default


def get_receipt_match_threshold(db: Session) -> int:
    """Schwellwert (0–100) für Kassenzettel-Treffer; auf sinnvollen Bereich geklemmt."""
    row = db.get(Setting, RECEIPT_THRESHOLD_KEY)
    if row is None:
        return RECEIPT_THRESHOLD_DEFAULT
    try:
        return max(0, min(100, int(row.value)))
    except ValueError:
        return RECEIPT_THRESHOLD_DEFAULT


@router.get("", response_model=list[SettingOut])
def list_settings(
    db: Session = Depends(get_db), _: User = Depends(get_current_user)
) -> list[SettingOut]:
    rows = db.query(Setting).all()
    known = {r.key: r.value for r in rows}
    known.setdefault(EXPIRY_WARNING_KEY, str(get_expiry_warning_days(db)))
    known.setdefault(RECEIPT_THRESHOLD_KEY, str(get_receipt_match_threshold(db)))
    return [SettingOut(key=k, value=v) for k, v in known.items()]


@router.put("/{key}", response_model=SettingOut)
def set_setting(
    key: str,
    value: str,
    db: Session = Depends(get_db),
    _: User = Depends(require_admin),
) -> SettingOut:
    row = db.get(Setting, key)
    if row is None:
        row = Setting(key=key, value=value)
        db.add(row)
    else:
        row.value = value
    db.commit()
    return SettingOut(key=key, value=value)