#!/usr/bin/env python
from random import choice
from collections import defaultdict
from datetime import datetime
from dataclasses import dataclass
ALL_CATEGORIES = [f'category-{i}' for i in range(5000)]
# z requesta
REQUIRED = [f'category-{i}' for i in range(500)]


@dataclass(frozen = True)
class Product:
    name: str
    id: int
    category: str

def generate_product(idx: int) -> Product:
    return Product(f'product-{idx}', idx, choice(ALL_CATEGORIES))

DATABASE_ITEMS_COUNT = 5000000


def rozwiazanie_pieprzyk():
    print('rozwiazanie pieprzyk')
    required_categories = set(REQUIRED)
    products_by_category = {}
    for product in [generate_product(i) for i in range(DATABASE_ITEMS_COUNT)]:
        if product.category not in required_categories:
            continue
        products_by_category.setdefault(product.category, [])
        products_by_category[product.category].append(product)
    len_all = DATABASE_ITEMS_COUNT
    len_found = 0
    for required_category in required_categories:
        len_found += len(products_by_category[required_category])
    print(f'znaleziono {len_found}/{len_all} produktów ({(len_found / len_all) * 100}%)')


def rozwiazanie_niedzwiedz():
    print('rozwiazanie niedzwiedz')
    required_categories = set(REQUIRED)
    database_products = (generate_product(i) for i in range(DATABASE_ITEMS_COUNT))
    len_found = sum((
        1 for product in database_products if product.category in required_categories
    ))
    len_all = DATABASE_ITEMS_COUNT
    print(
        f'znaleziono {len_found}/{len_all} produktów ({(len_found / len_all) * 100}%)'
    )


start = datetime.now()
rozwiazanie_pieprzyk()
print('koniec:', datetime.now() - start)


start = datetime.now()
rozwiazanie_niedzwiedz()
print('koniec:', datetime.now() - start)