"""批量重新提取所有论文的图片 — 下载 PDF + PicoDet 检测 + caption 匹配.

用法:
    PROXY_SERVER=http://... uv run python scripts/reextract_images.py
    uv run python scripts/reextract_images.py --limit 10       # 只处理前 10 篇
    uv run python scripts/reextract_images.py --id 2512.24880   # 只处理指定论文
"""

from __future__ import annotations

import json
import logging
import os
import sys
import time
from concurrent.futures import ThreadPoolExecutor, as_completed
from pathlib import Path

import requests

# 让脚本可以从项目根目录直接运行
sys.path.insert(0, str(Path(__file__).resolve().parent.parent))

from dotenv import load_dotenv

load_dotenv()

from app.database import SessionLocal, init_db, engine  # noqa: E402
from app.models import Paper  # noqa: E402
from app.services.pdf_image_extractor import extract_images_from_pdf  # noqa: E402
from app.utils import TMP_DIR  # noqa: E402
from sqlalchemy import select  # noqa: E402

logging.basicConfig(
    level=logging.INFO,
    format="%(asctime)s %(levelname)-5s %(message)s",
    datefmt="%H:%M:%S",
)
logger = logging.getLogger(__name__)

# 下载并发数
MAX_WORKERS = 3
# 下载超时（秒）
DOWNLOAD_TIMEOUT = 120


def _get_session() -> requests.Session:
    """创建带代理的 HTTP session。"""
    sess = requests.Session()
    sess.headers.update({"User-Agent": "hf-daily-papers/1.0"})
    proxy = os.environ.get("PROXY_SERVER") or os.environ.get("HTTPS_PROXY")
    if proxy:
        sess.proxies = {"http": proxy, "https": proxy}
        logger.info("使用代理: %s", proxy)
    else:
        logger.warning("未设置代理 (PROXY_SERVER / HTTPS_PROXY)，直连 arxiv.org")
    return sess


def download_pdf(session: requests.Session, arxiv_id: str, pdf_url: str) -> Path | None:
    """下载 PDF 到 data/tmp/{arxiv_id}/paper.pdf，返回路径或 None。"""
    dest_dir = TMP_DIR / arxiv_id
    dest = dest_dir / "paper.pdf"
    if dest.exists() and dest.stat().st_size > 1000:
        return dest

    dest_dir.mkdir(parents=True, exist_ok=True)
    try:
        resp = session.get(pdf_url, timeout=DOWNLOAD_TIMEOUT, allow_redirects=True)
        resp.raise_for_status()
        dest.write_bytes(resp.content)
        return dest
    except Exception as exc:
        logger.warning("下载失败 %s: %s", arxiv_id, exc)
        return None


def process_one(session: requests.Session, arxiv_id: str, pdf_url: str) -> dict:
    """处理单篇论文：下载 → 提取图片 → 返回统计。"""
    result = {"arxiv_id": arxiv_id, "downloaded": False, "extracted": 0, "error": None}

    # 下载 PDF
    pdf_path = download_pdf(session, arxiv_id, pdf_url)
    if pdf_path is None:
        result["error"] = "download_failed"
        return result
    result["downloaded"] = True

    # 提取图片
    try:
        n = extract_images_from_pdf(arxiv_id, pdf_path)
        result["extracted"] = n
    except Exception as exc:
        logger.warning("提取失败 %s: %s", arxiv_id, exc, exc_info=True)
        result["error"] = f"extract_failed: {exc}"
        return result

    # 统计 matched / orphan
    mf = Path(f"data/papers/{arxiv_id}/images/manifest.json")
    if mf.exists():
        m = json.loads(mf.read_text(encoding="utf-8"))
        result["matched"] = sum(1 for v in m.values() if "(p" not in v.get("label", ""))
        result["orphan"] = sum(1 for v in m.values() if "(p" in v.get("label", ""))

    return result


def main():
    import argparse

    parser = argparse.ArgumentParser(description="批量重新提取论文图片")
    parser.add_argument("--limit", type=int, default=0, help="只处理前 N 篇")
    parser.add_argument("--id", dest="arxiv_id", help="只处理指定 arxiv_id")
    parser.add_argument("--workers", type=int, default=MAX_WORKERS, help="并发数")
    args = parser.parse_args()

    # 初始化数据库
    os.makedirs("data/db", exist_ok=True)
    init_db(engine)

    # 读取论文列表
    db = SessionLocal()
    try:
        if args.arxiv_id:
            papers = (
                db.execute(select(Paper).where(Paper.arxiv_id == args.arxiv_id))
                .scalars()
                .all()
            )
        else:
            papers = db.execute(select(Paper)).scalars().all()
    finally:
        db.close()

    if args.limit > 0:
        papers = papers[: args.limit]

    total = len(papers)
    logger.info("待处理论文: %d 篇", total)
    if total == 0:
        return

    session = _get_session()

    # 统计
    done = 0
    failed = 0
    total_extracted = 0
    total_matched = 0
    total_orphan = 0
    t0 = time.time()

    with ThreadPoolExecutor(max_workers=args.workers) as pool:
        futures = {}
        for p in papers:
            f = pool.submit(process_one, session, p.arxiv_id, p.pdf_url)
            futures[f] = p.arxiv_id

        for f in as_completed(futures):
            arxiv_id = futures[f]
            try:
                r = f.result()
            except Exception as exc:
                logger.error("异常 %s: %s", arxiv_id, exc)
                failed += 1
                done += 1
                continue

            done += 1
            if r["error"]:
                failed += 1
                logger.info("[%d/%d] ✗ %s — %s", done, total, arxiv_id, r["error"])
            else:
                total_extracted += r["extracted"]
                total_matched += r.get("matched", 0)
                total_orphan += r.get("orphan", 0)
                matched = r.get("matched", 0)
                orphan = r.get("orphan", 0)
                elapsed = time.time() - t0
                rate = done / elapsed if elapsed > 0 else 0
                eta = (total - done) / rate if rate > 0 else 0
                logger.info(
                    "[%d/%d] ✓ %s — %d 张 (matched=%d, orphan=%d) ETA %.0fs",
                    done,
                    total,
                    arxiv_id,
                    r["extracted"],
                    matched,
                    orphan,
                    eta,
                )

    elapsed = time.time() - t0
    logger.info("=" * 60)
    logger.info(
        "完成: %d/%d 成功, %d 失败, 耗时 %.1fs",
        done - failed,
        total,
        failed,
        elapsed,
    )
    logger.info(
        "图片: %d 总计, %d matched, %d orphan (%.1f%%)",
        total_extracted,
        total_matched,
        total_orphan,
        total_orphan / total_extracted * 100 if total_extracted else 0,
    )


if __name__ == "__main__":
    main()