from datetime import datetime, timezone

from pymongo import MongoClient, ASCENDING, DESCENDING, TEXT
from config import MONGO_URI, MONGO_DB


def get_db():
    client = MongoClient(MONGO_URI)
    return client[MONGO_DB]


def ensure_indexes(db):
    db.categories.create_index("parentId")
    db.categories.create_index("isLeaf")

    db.products.create_index("mainCategoryId")
    db.products.create_index([("archived", ASCENDING), ("lastSeen", DESCENDING)])
    db.products.create_index([("name", TEXT)])

    db.price_history.create_index([("productId", ASCENDING), ("scrapedAt", DESCENDING)])
    db.price_history.create_index([("scrapedAt", DESCENDING)])

    db.scrape_runs.create_index([("startedAt", DESCENDING)])


def upsert_category(db, cat: dict):
    db.categories.update_one(
        {"_id": cat["_id"]},
        {"$set": cat},
        upsert=True,
    )


def upsert_categories(db, cats: list[dict]):
    for cat in cats:
        upsert_category(db, cat)


def upsert_product(db, base: dict, prices: dict, stock: dict, categories: list[dict]):
    now = datetime.now(timezone.utc)
    product_id = base["id"]

    sale_raw = prices.get("sales", [])
    sale = None
    if sale_raw:
        s = sale_raw[0]
        sale = {
            "type": s.get("type"),
            "price": s["price"]["amount"],
            "pricePerUnit": s.get("pricePerUnit", {}).get("amount"),
            "badge": (s.get("badges") or [{}])[0].get("title"),
            "validTill": s.get("validTill"),
        }

    category_path = [c["id"] for c in categories] if categories else []

    doc = {
        "name": base["name"],
        "slug": base.get("slug"),
        "brand": base.get("brand"),
        "unit": base.get("unit"),
        "textualAmount": base.get("textualAmount"),
        "weightedItem": base.get("weightedItem", False),
        "mainCategoryId": base.get("mainCategoryId"),
        "categoryPath": category_path,
        "allCategories": [
            {"id": c["id"], "name": c["name"], "level": c.get("level", 0)}
            for c in categories
        ] if categories else [],
        "countryCode": base.get("flag"),
        "images": base.get("images", []),
        "badges": base.get("badges", []),
        "archived": base.get("archived", False),
        "premiumOnly": base.get("premiumOnly", False),
        "currentPrice": prices["price"]["amount"],
        "currentPricePerUnit": prices.get("pricePerUnit", {}).get("amount"),
        "currency": prices["price"].get("currency", "CZK"),
        "sale": sale,
        "inStock": stock.get("inStock", False),
        "maxBasketAmount": stock.get("maxBasketAmount", 0),
        "packageAmount": stock.get("packageInfo", {}).get("amount"),
        "packageUnit": stock.get("packageInfo", {}).get("unit"),
        "warehouseId": stock.get("warehouseId"),
        "lastSeen": now,
        "lastScrapedAt": now,
    }

    db.products.update_one(
        {"_id": product_id},
        {
            "$set": doc,
            "$setOnInsert": {"firstSeen": now},
        },
        upsert=True,
    )

    db.price_history.insert_one({
        "productId": product_id,
        "scrapedAt": now,
        "price": prices["price"]["amount"],
        "pricePerUnit": prices.get("pricePerUnit", {}).get("amount"),
        "inStock": stock.get("inStock", False),
        "sale": sale,
    })


def upsert_products(db, bases: list, prices_list: list, stocks: list, categories_list: list):
    prices_map = {p["productId"]: p for p in prices_list}
    stock_map = {s["productId"]: s for s in stocks}
    cats_map = {c["productId"]: c.get("categories", []) for c in categories_list}

    for base in bases:
        pid = base["id"]
        upsert_product(
            db,
            base,
            prices_map.get(pid, {"price": {"amount": 0}}),
            stock_map.get(pid, {}),
            cats_map.get(pid, []),
        )


def log_scrape_run(db, run_data: dict):
    run_data.setdefault("startedAt", datetime.now(timezone.utc))
    db.scrape_runs.insert_one(run_data)