from __future__ import annotations

"""Deduplicate article entries inside stored clusters.

This cleans existing SQLite payloads so a cluster only keeps one article record
per canonical article key (preferably the URL path/article id).

Usage:
  ./.venv/bin/python scripts/dedup_articles_in_clusters.py --dry-run
  ./.venv/bin/python scripts/dedup_articles_in_clusters.py
"""

import argparse
import json
import sys
from pathlib import Path
from typing import Any
from urllib.parse import urlparse

ROOT = Path(__file__).resolve().parents[1]
sys.path.insert(0, str(ROOT))

from news_mcp.config import DB_PATH
from news_mcp.storage.sqlite_store import SQLiteClusterStore


def _article_key(article: dict[str, Any]) -> str:
    url = str(article.get("url") or "").strip()
    if not url:
        return str(article.get("title") or "")
    try:
        parsed = urlparse(url)
        parts = [p for p in parsed.path.split("/") if p]
        if parts:
            return parts[-1]
    except Exception:
        pass
    return url


def _dedup_articles(articles: list[dict[str, Any]]) -> list[dict[str, Any]]:
    seen = set()
    out = []
    for article in articles:
        key = _article_key(article)
        if key in seen:
            continue
        seen.add(key)
        out.append(article)
    return out


def main() -> None:
    parser = argparse.ArgumentParser(description="Deduplicate article entries inside stored clusters")
    parser.add_argument("--db", type=Path, default=DB_PATH)
    parser.add_argument("--dry-run", action="store_true")
    parser.add_argument("--limit", type=int, default=None)
    args = parser.parse_args()

    store = SQLiteClusterStore(args.db)
    with store._conn() as conn:  # noqa: SLF001 - maintenance script
        rows = conn.execute("SELECT cluster_id, topic, payload FROM clusters ORDER BY updated_at ASC").fetchall()

    if args.limit is not None:
        rows = rows[: args.limit]

    total = 0
    updated = 0

    print(f"starting article dedup: clusters={len(rows)} dry_run={args.dry_run}")

    for cluster_id, topic, payload_json in rows:
        total += 1
        try:
            cluster = json.loads(payload_json)
        except Exception:
            continue

        articles = cluster.get("articles", []) or []
        deduped = _dedup_articles([a for a in articles if isinstance(a, dict)])
        if len(deduped) == len(articles):
            continue

        cluster = dict(cluster)
        cluster["articles"] = deduped
        if not args.dry_run:
            store.upsert_clusters([cluster], topic=topic or cluster.get("topic", "other"))
        updated += 1

        if updated % 25 == 0:
            print(f"updated={updated} processed={total}")

    print({"total_scanned": total, "updated": updated, "dry_run": args.dry_run})


if __name__ == "__main__":
    main()