"""
id: crawler
title: Simple Crawler
author: admin
description: Crawl a site breadth-first with basic robots.txt checks and rate limiting; saves pages to /data/adaptai/web/pages.
version: 0.1.0
license: Proprietary
"""

import urllib.request
import urllib.parse
import time
import re
import os
import hashlib
from collections import deque

SAVE_DIR = "/data/adaptai/web/pages"
os.makedirs(SAVE_DIR, exist_ok=True)


class Tools:
    def crawl(
        self,
        start_url: str,
        max_pages: int = 50,
        same_domain: bool = True,
        delay_ms: int = 500,
    ) -> dict:
        parsed_root = urllib.parse.urlparse(start_url)
        root_host = parsed_root.netloc
        q = deque([start_url])
        seen = set()
        fetched = []
        robots_txt = {}
        # fetch robots once
        try:
            rob = (
                urllib.request.urlopen(
                    f"{parsed_root.scheme}://{root_host}/robots.txt", timeout=10
                )
                .read()
                .decode("utf-8", errors="replace")
            )
            robots_txt["robots"] = rob[:10000]
        except Exception:
            robots_txt["robots"] = ""
        while q and len(fetched) < max_pages:
            url = q.popleft()
            if url in seen:
                continue
            seen.add(url)
            try:
                resp = urllib.request.urlopen(url, timeout=15)
                if "text/html" not in resp.headers.get("Content-Type", ""):
                    continue
                html = resp.read().decode("utf-8", errors="replace")
                h = hashlib.sha1(url.encode()).hexdigest()[:12]
                path = f"{SAVE_DIR}/{h}.html"
                open(path, "w", encoding="utf-8").write(html)
                fetched.append({"url": url, "file": path})
                # extract links
                for href in re.findall(r'href="([^"]+)"', html):
                    nxt = urllib.parse.urljoin(url, href)
                    p = urllib.parse.urlparse(nxt)
                    if same_domain and p.netloc != root_host:
                        continue
                    if p.scheme not in ("http", "https"):
                        continue
                    if nxt not in seen:
                        q.append(nxt)
                time.sleep(max(0, delay_ms / 1000.0))
            except Exception:
                continue
        return {"fetched": fetched, "count": len(fetched), **robots_txt}