# at top of persist_snapshot.py:
from datetime import datetime
from sqlalchemy import (
     select, tuple_
)
from typing import Dict

from models.market import (
    NavTop,
    NavSub,
)
from db.session import get_session




async def save_nav(nav: Dict) -> None:
    async with get_session() as session:
        await _save_nav(session, nav)
        await session.commit()

async def _save_nav(session, nav: Dict) -> None:
    print('===================SAVE NAV========================')
    print(nav)
    now = datetime.utcnow()

    incoming_top_slugs = set()
    incoming_sub_keys = set()  # (top_slug, sub_slug)

    # First pass: collect slugs
    for label, data in (nav.get("cats") or {}).items():
        top_slug = (data or {}).get("slug")
        if not top_slug:
            continue
        incoming_top_slugs.add(top_slug)

        for s in (data.get("subs") or []):
            sub_slug = s.get("slug")
            if sub_slug:
                incoming_sub_keys.add((top_slug, sub_slug))

    # Soft-delete stale NavSub entries
    # This requires joining NavTop to access top_slug
    subs_to_delete = await session.execute(
        select(NavSub)
        .join(NavTop, NavSub.top_id == NavTop.id)
        .where(
            NavSub.deleted_at.is_(None),
            ~tuple_(NavTop.slug, NavSub.slug).in_(incoming_sub_keys)
        )
    )
    for sub in subs_to_delete.scalars():
        sub.deleted_at = now

    # Soft-delete stale NavTop entries
    tops_to_delete = await session.execute(
        select(NavTop)
        .where(
            NavTop.deleted_at.is_(None),
            ~NavTop.slug.in_(incoming_top_slugs)
        )
    )
    for top in tops_to_delete.scalars():
        top.deleted_at = now

    await session.flush()

    # Upsert NavTop and NavSub
    for label, data in (nav.get("cats") or {}).items():
        top_slug = (data or {}).get("slug")
        if not top_slug:
            continue

        res = await session.execute(
            select(NavTop).where(NavTop.slug == top_slug)
        )
        top = res.scalar_one_or_none()

        if top:
            top.label = label
            top.deleted_at = None
        else:
            top = NavTop(label=label, slug=top_slug)
            session.add(top)

        await session.flush()

        for s in (data.get("subs") or []):
            sub_slug = s.get("slug")
            if not sub_slug:
                continue
            sub_label = s.get("label")
            sub_href = s.get("href")

            res_sub = await session.execute(
                select(NavSub).where(
                    NavSub.slug == sub_slug,
                    NavSub.top_id == top.id
                )
            )
            sub = res_sub.scalar_one_or_none()
            if sub:
                sub.label = sub_label
                sub.href = sub_href
                sub.deleted_at = None
            else:
                session.add(NavSub(top_id=top.id, label=sub_label, slug=sub_slug, href=sub_href))