"""Helpers partagés par les routers CRUD."""

import uuid
from collections.abc import Iterable

from fastapi import HTTPException
from sqlalchemy import delete
from sqlmodel import Session, select

from app.models import Skill


def owned_or_404(instance, edition_id: uuid.UUID):
    """404 si l'instance est absente ou rattachée à une autre édition."""
    if instance is None or instance.edition_id != edition_id:
        raise HTTPException(status_code=404, detail={"code": "error.not_found"})
    return instance


def resolve_skills(
    session: Session, edition_id: uuid.UUID, codes: Iterable[str]
) -> list[Skill]:
    """Récupère ou crée les compétences de l'édition pour les codes donnés."""
    existing = {
        s.code: s
        for s in session.exec(
            select(Skill).where(Skill.edition_id == edition_id)
        )
    }
    resolved: list[Skill] = []
    seen: set[str] = set()
    for raw in codes:
        code = raw.strip()
        if not code or code in seen:
            continue
        seen.add(code)
        skill = existing.get(code)
        if skill is None:
            skill = Skill(edition_id=edition_id, code=code, label=code)
            session.add(skill)
            session.flush()
            existing[code] = skill
        resolved.append(skill)
    return resolved


def replace_links(
    session: Session, link_model, *, filter_column, filter_value, pairs
) -> None:
    """Remplace toutes les lignes d'une table d'association pour une clé."""
    session.execute(
        delete(link_model).where(filter_column == filter_value)
    )
    for row in pairs:
        session.add(link_model(**row))