"""Shared note↔label membership reconciliation. The "set a note's MANUAL (picker)
labels, leave the tag-sourced ones alone" logic was duplicated line-for-line between
the labels-picker API (notes.set_note_labels) and sync push (sync._apply_note_manual_labels).
Single home so both stay in lockstep. via_tag=True rows track the body #tags and are
governed by _reconcile_tags — this function never touches them."""
from __future__ import annotations

from sqlalchemy import select

from .models.label import Label, NoteLabel
from .models.note import Note


async def resolve_owned_label_ids(db, label_ids, owner_id) -> set:
    """Of `label_ids` (an iterable of UUIDs), the subset actually owned by `owner_id`.
    Callers parse/validate the raw ids first; this just enforces ownership."""
    ids = list(label_ids)
    if not ids:
        return set()
    return set(
        (await db.scalars(select(Label.id).where(Label.owner_id == owner_id, Label.id.in_(ids)))).all()
    )


async def reconcile_manual_labels(db, note: Note, owned_label_ids: set) -> None:
    """Make the note's MANUAL (via_tag=False) memberships exactly `owned_label_ids`:
    drop manual rows no longer wanted, add missing ones. Tag-sourced rows survive
    untouched. Caller commits."""
    existing = (await db.scalars(select(NoteLabel).where(NoteLabel.note_id == note.id))).all()
    attached = {r.label_id for r in existing}
    for r in existing:
        if not r.via_tag and r.label_id not in owned_label_ids:
            await db.delete(r)
    for lid in owned_label_ids:
        if lid not in attached:
            db.add(NoteLabel(note_id=note.id, label_id=lid, via_tag=False))