#!/usr/bin/env python3
"""Read a Korean catalog segment and keep only ordinary sale listings.

APIAUTO_KEY=... python outreach/articles/02-catalog-demo.py --brand Kia --year-min 2019

The script is read-only. It demonstrates cursor pagination and client-side
sell_type filtering; it is not a background sync worker or an availability
guarantee. Each returned car consumes one API record.
"""

import argparse
import json
import os
import sys
import urllib.error
import urllib.parse
import urllib.request


BASE = os.environ.get("APIAUTO_URL", "https://api.apiauto.space").rstrip("/")


def get(path: str, **params: object) -> dict:
    key = os.environ.get("APIAUTO_KEY")
    if not key:
        raise RuntimeError("Set APIAUTO_KEY in the environment")
    query = urllib.parse.urlencode({k: v for k, v in params.items() if v is not None})
    request = urllib.request.Request(
        f"{BASE}{path}?{query}" if query else f"{BASE}{path}",
        headers={"X-API-Key": key, "User-Agent": "apiauto-article-02-demo"},
    )
    with urllib.request.urlopen(request, timeout=30) as response:
        return json.load(response)


def ordinary_sale(car: dict) -> bool:
    """Unknown deal types are withheld until somebody reviews them."""
    return (
        car.get("is_active") is True
        and (car.get("raw") or {}).get("sell_type") == "normal"
        and bool(car.get("price_usd"))
        and float(car["price_usd"]) > 0
    )


def find_sales(brand: str, year_min: int, wanted: int, page_size: int) -> tuple[list[dict], int]:
    sales: list[dict] = []
    cursor = None
    read = 0
    while len(sales) < wanted:
        page = get(
            "/v1/cars", market="kr", brand=brand, year_min=year_min,
            sort="price", limit=page_size, cursor=cursor,
        )
        items = page["items"]
        read += len(items)
        sales.extend(car for car in items if ordinary_sale(car))
        cursor = page.get("next_cursor")
        if not cursor:
            break
    return sales[:wanted], read


def main() -> int:
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("--brand", default="Kia")
    parser.add_argument("--year-min", type=int, default=2019)
    parser.add_argument("--wanted", type=int, default=20)
    parser.add_argument("--page-size", type=int, default=20, choices=range(1, 101), metavar="1..100")
    args = parser.parse_args()
    if args.wanted < 1:
        parser.error("--wanted must be positive")
    try:
        sales, read = find_sales(args.brand, args.year_min, args.wanted, args.page_size)
    except (RuntimeError, urllib.error.HTTPError, urllib.error.URLError, TimeoutError) as exc:
        print(f"Request failed: {exc}", file=sys.stderr)
        return 1
    print(f"Read {read} cards; found {len(sales)} ordinary sale listings.")
    for car in sales:
        print(f"{car['id']}  {car['title']}  ${car['price_usd']}  {car.get('listing_url') or ''}")
    return 0


if __name__ == "__main__":
    raise SystemExit(main())