"""Projects catalog changes into Redis for the Shop frontend to read."""
from __future__ import annotations

import json

from sqlalchemy.orm import Session

from core.redis_client import redis_client

from .models import Category, Product


def _product_to_dict(p: Product) -> dict:
    return {
        "id": p.id,
        "sku": p.sku,
        "name": p.name,
        "description": p.description,
        "price": float(p.price),
        "currency": p.currency,
        "stock": p.stock,
        "active": p.active,
        "image_url": p.image_url,
        "category_id": p.category_id,
        "attributes": p.attributes or {},
    }


def _category_to_dict(c: Category) -> dict:
    return {
        "id": c.id,
        "slug": c.slug,
        "name": c.name,
        "parent_id": c.parent_id,
        "sort_order": c.sort_order,
    }


def project_product(db: Session, product_id: int) -> None:
    p = db.get(Product, product_id)
    if not p or not p.active:
        redis_client.delete(f"product:{product_id}")
        _refresh_product_list(db)
        return
    redis_client.set(f"product:{product_id}", json.dumps(_product_to_dict(p)))
    _refresh_product_list(db)


def delete_product_from_cache(product_id: int, db: Session) -> None:
    redis_client.delete(f"product:{product_id}")
    _refresh_product_list(db)


def _refresh_product_list(db: Session) -> None:
    ids = [row[0] for row in db.query(Product.id).filter(Product.active.is_(True)).all()]
    redis_client.set("product:list", json.dumps(ids))


def project_category(db: Session, category_id: int) -> None:
    c = db.get(Category, category_id)
    if not c:
        redis_client.delete(f"category:{category_id}")
    else:
        redis_client.set(f"category:{category_id}", json.dumps(_category_to_dict(c)))
    _refresh_category_tree(db)


def delete_category_from_cache(category_id: int, db: Session) -> None:
    redis_client.delete(f"category:{category_id}")
    _refresh_category_tree(db)


def _refresh_category_tree(db: Session) -> None:
    cats = db.query(Category).order_by(Category.sort_order, Category.id).all()
    data = [_category_to_dict(c) for c in cats]
    redis_client.set("category:tree", json.dumps(data))


def rebuild_all(db: Session) -> None:
    # Refresh every product/category key
    for p in db.query(Product).all():
        if p.active:
            redis_client.set(f"product:{p.id}", json.dumps(_product_to_dict(p)))
    for c in db.query(Category).all():
        redis_client.set(f"category:{c.id}", json.dumps(_category_to_dict(c)))
    _refresh_product_list(db)
    _refresh_category_tree(db)