"""Serbian Supreme Court (Vrhovni sud) via the public Solr search listing.

The court runs Drupal 7 with a Solr backend at `vrh.sud.rs`. The
`/sr-lat/solr-search-page/results` endpoint sorts by date (newest first) and
exposes each case's reference (e.g., "Rev 102/2025"), detail URL, and
decision date in the result-summary block — enough for a Goldenset without
fetching detail pages.

Civil filter: case-ID prefix `Rev/Rev1/Rev2/Prev/Gzz/Gzz1` (civil revision).
Drop `Kzz`, `Kž` (criminal). Server-side `Građanska materija` (civil matter)
marker is also captured into metadata.
"""

import logging
import re
import time
from datetime import date

import requests
import urllib3

from legex.models.base import Case
from legex.scrapers.base import BaseScraper

# vrh.sud.rs serves a Let's Encrypt cert without the intermediate in the chain
# (AIA-only), so `requests` can't verify it out of the box. Disable verification
# for this read-only scrape of public open-data; we don't transmit secrets.
urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)

log = logging.getLogger(__name__)

BASE_URL = "https://vrh.sud.rs"
SEARCH_PATH = "/sr-lat/solr-search-page/results"
USER_AGENT = "legex-research (open-data, friendly)"
RESULTS_PER_PAGE = 50
MAX_PAGES = 400
DELAY_SECONDS = 0.5

_RESULT_BLOCK_RE = re.compile(
    r'<li class="search-result">(.*?)</li>', re.DOTALL
)
_LINK_RE = re.compile(
    r'<h3[^>]*class="title[^"]*"[^>]*>\s*<a href="([^"]+)"[^>]*>(.*?)</a>',
    re.DOTALL,
)
_SUMMARY_RE = re.compile(
    r'<div class="result-summary">(.*?)</div>', re.DOTALL
)
_DATE_RE = re.compile(r"Datum:\s*(\d{2})\.(\d{2})\.(\d{4})")
_PREFIX_RE = re.compile(r"^([A-Za-zžŽ]+\d*)\s")

CIVIL_PREFIXES = {"rev", "rev1", "rev2", "prev", "gzz", "gzz1"}
CRIMINAL_PREFIXES = {"kzz", "kž", "kz"}


def _normalize_text(raw: str) -> str:
    return re.sub(r"\s+", " ", re.sub(r"<[^>]+>", " ", raw)).strip()


def _parse_block(block_html: str) -> dict | None:
    link_match = _LINK_RE.search(block_html)
    if not link_match:
        return None
    href = link_match.group(1).strip()
    case_ref = _normalize_text(link_match.group(2))
    # Strip optional category code suffix like "3.2.1.3.1" from end of title.
    case_id = re.sub(r"\s+\d+(\.\d+)+$", "", case_ref).strip()

    summary_match = _SUMMARY_RE.search(block_html)
    summary_text = _normalize_text(summary_match.group(1)) if summary_match else ""

    decision_date: date | None = None
    d = _DATE_RE.search(summary_text)
    if d:
        try:
            decision_date = date(int(d.group(3)), int(d.group(2)), int(d.group(1)))
        except ValueError:
            decision_date = None

    matter = "other"
    if "Građanska" in summary_text or "Gradjanska" in summary_text:
        matter = "civil"
    elif "Krivična" in summary_text or "Krivicna" in summary_text:
        matter = "criminal"
    elif "Upravna" in summary_text:
        matter = "administrative"

    prefix_match = _PREFIX_RE.search(case_id)
    prefix = prefix_match.group(1).lower() if prefix_match else ""

    return {
        "case_id": case_id,
        "link": href if href.startswith("http") else f"{BASE_URL}{href}",
        "decision_date": decision_date,
        "matter": matter,
        "case_prefix": prefix,
        "summary": summary_text,
    }


class RSScraper(BaseScraper):
    country = "Serbien"

    def scrape(
        self,
        start_date: date | None = None,
        end_date: date | None = None,
    ) -> list[Case]:
        session = requests.Session()
        session.headers.update({"User-Agent": USER_AGENT})

        cases: list[Case] = []
        seen: set[str] = set()
        for page in range(0, MAX_PAGES):
            url = (
                f"{BASE_URL}{SEARCH_PATH}"
                f"?court_type=sc&results={RESULTS_PER_PAGE}"
                f"&page={page}&sorting=by_date_down"
            )
            try:
                resp = session.get(url, timeout=30, verify=False)
            except requests.RequestException as e:
                log.warning("RS request error page %d: %s", page, e)
                break
            if resp.status_code != 200:
                log.warning("RS HTTP %d on page %d", resp.status_code, page)
                break

            blocks = _RESULT_BLOCK_RE.findall(resp.text)
            if not blocks:
                log.info("RS page %d: no results, stopping", page)
                break

            new_on_page = 0
            oldest_on_page: date | None = None
            for block in blocks:
                parsed = _parse_block(block)
                if not parsed:
                    continue
                if parsed["case_id"] in seen:
                    continue
                if (
                    start_date
                    and parsed["decision_date"]
                    and parsed["decision_date"] < start_date
                ):
                    if not oldest_on_page or parsed["decision_date"] < oldest_on_page:
                        oldest_on_page = parsed["decision_date"]
                    continue
                if (
                    end_date
                    and parsed["decision_date"]
                    and parsed["decision_date"] > end_date
                ):
                    continue

                seen.add(parsed["case_id"])
                new_on_page += 1
                if not oldest_on_page or (
                    parsed["decision_date"]
                    and parsed["decision_date"] < oldest_on_page
                ):
                    oldest_on_page = parsed["decision_date"]
                cases.append(
                    Case(
                        case_id=parsed["case_id"],
                        link=parsed["link"],
                        decision_date=parsed["decision_date"],
                        jurisdiction="rs",
                        language="sr",
                        full_text=None,
                        metadata={
                            "matter": parsed["matter"],
                            "case_prefix": parsed["case_prefix"],
                            "summary": parsed["summary"],
                        },
                    )
                )

            log.info(
                "RS page %d: %d blocks, %d new (oldest seen %s)",
                page,
                len(blocks),
                new_on_page,
                oldest_on_page,
            )

            # Sorted desc by date: once we fully cross start_date, no more in range.
            if (
                start_date
                and oldest_on_page
                and oldest_on_page < start_date
                and new_on_page == 0
            ):
                log.info("RS page %d entirely older than start_date; stopping", page)
                break

            time.sleep(DELAY_SECONDS)

        cases.sort(key=lambda c: c.decision_date or date.min, reverse=True)
        log.info("Collected %d Serbia cases", len(cases))
        return cases

    @staticmethod
    def civil_filter(cases: list[Case]) -> list[Case]:
        kept: list[Case] = []
        for c in cases:
            meta = c.metadata or {}
            prefix = (meta.get("case_prefix") or "").lower()
            matter = meta.get("matter")
            if prefix in CRIMINAL_PREFIXES:
                continue
            if matter == "criminal":
                continue
            if prefix in CIVIL_PREFIXES or matter == "civil":
                kept.append(c)
        log.info("RS civil_filter kept %d/%d", len(kept), len(cases))
        return kept