"""
Validate the float-cursor scrape by walking the float axis in BOTH directions and
comparing the recovered sell-order id sets. If ascending (lowest float first) and
descending (highest float first) independently land on the same listings, the
cursor is exhaustive and order-independent — i.e. the count is real, not an artifact
of walk direction or boundary double-counting.

    python verify_crosscheck.py "Glock-18 Candy Apple mw"
"""

import asyncio
import sys

import nodriver as uc

import worker

CAP = worker.PAGE_CAP
ASC = ("https://cs.money/market/buy/?search={q}"
       "&order=asc&sort=float&minFloat={cur:.12f}&maxFloat=1")
DESC = ("https://cs.money/market/buy/?search={q}"
        "&order=desc&sort=float&minFloat=0&maxFloat={cur:.12f}")


async def walk(page, q, template, ascending, max_fetches=60):
    seen = {}
    cur = 0.0 if ascending else 1.0
    fetches = 0
    while fetches < max_fetches:
        status, body = await worker.fetch_json(page, template.format(q=q, cur=cur))
        fetches += 1
        if "Just a moment" in body or "challenge-platform" in body:
            return seen, fetches, "challenged"
        items = worker.extract_items(body)
        floats = []
        for it in items:
            if it.get("id") is not None:
                seen[it["id"]] = it
            fl = (it.get("asset") or {}).get("float")
            if isinstance(fl, (int, float)):
                floats.append(fl)
        if len(items) < CAP:
            return seen, fetches, "completed"
        nxt = (max(floats) if ascending else min(floats)) if floats else None
        if nxt is None or (ascending and nxt <= cur) or (not ascending and nxt >= cur):
            return seen, fetches, "stuck"
        cur = nxt
        await page.sleep(worker.DELAY)
    return seen, fetches, "fetch-cap"


async def main():
    search = " ".join(sys.argv[1:]) or "Glock-18 Candy Apple mw"
    q = worker.urllib.parse.quote_plus(search)
    browser = await uc.start(headless=False, browser_args=["--blink-settings=imagesEnabled=false"])
    try:
        page = await browser.get("about:blank")
        await worker.warm(page)

        asc, fa, ra = await walk(page, q, ASC, ascending=True)
        print(f"ASC : {len(asc):4d} ids   {fa} fetches   {ra}")
        desc, fd, rd = await walk(page, q, DESC, ascending=False)
        print(f"DESC: {len(desc):4d} ids   {fd} fetches   {rd}")

        a, d = set(asc), set(desc)
        union = a | d
        print("\n=== cross-check ===")
        print(f"  ASC only:        {len(a - d)}")
        print(f"  DESC only:       {len(d - a)}")
        print(f"  in both:         {len(a & d)}")
        print(f"  UNION (distinct):{len(union)}")
        agree = "AGREE — count is solid" if a == d else "DISAGREE — one walk missed listings"
        print(f"  verdict: {agree}")
    finally:
        browser.stop()


if __name__ == "__main__":
    uc.loop().run_until_complete(main())