"""Fetch one provider pricing page as text, only if robots.txt allows it. At most 1 request per second.
Pages go to intern/pages/ for a human-style read; only extracted facts go into data/free_tiers.csv."""
import html
import pathlib
import re
import sys
import time
import urllib.parse
import urllib.request
import urllib.robotparser

UA = "free-tier-dataset/0.1 (+mailto:novusops@mail.grokbot.com)"
ROOT = pathlib.Path(__file__).resolve().parent.parent


def allowed(url):
    p = urllib.parse.urlparse(url)
    rp = urllib.robotparser.RobotFileParser()
    rp.set_url(f"{p.scheme}://{p.netloc}/robots.txt")
    try:
        req = urllib.request.Request(rp.url, headers={"User-Agent": UA})
        with urllib.request.urlopen(req, timeout=20) as r:
            rp.parse(r.read().decode(errors="ignore").splitlines())
    except Exception:
        rp.parse([])  # no robots.txt reachable: treat as no rules
    time.sleep(1)
    return rp.can_fetch(UA, url)


def to_text(raw):
    raw = re.sub(r"(?is)<(script|style|noscript|svg)[^>]*>.*?</\1>", " ", raw)
    raw = re.sub(r"(?s)<[^>]+>", " ", raw)
    return re.sub(r"\s+", " ", html.unescape(raw))


def fetch(pid, url):
    if not allowed(url):
        print(f"{pid}: robots.txt disallows {url}, skipped")
        return None
    req = urllib.request.Request(url, headers={"User-Agent": UA})
    with urllib.request.urlopen(req, timeout=30) as r:
        txt = to_text(r.read().decode(errors="ignore"))
    (ROOT / "intern" / "pages" / f"{pid}.txt").write_text(txt)
    time.sleep(1)
    print(f"{pid}: {len(txt)} chars")
    return txt


if __name__ == "__main__":
    fetch(sys.argv[1], sys.argv[2])