"""历史日报批量导入（解析 → 入库，幂等）。"""

from __future__ import annotations

import re
from dataclasses import dataclass, field
from pathlib import Path

from loguru import logger

from report_db import connect, exists_report, save_report
from report_import.parser import ReportParseError, parse_report

_REPORT_FILE_RE = re.compile(r"([a-z]+)_news_daily_\d{8}(?:_\d{4,6})?\.html$")


@dataclass
class ImportStats:
    """一次导入的统计结果。"""

    scanned: int = 0  # 扫描到的日报文件数
    imported: int = 0  # 新入库
    skipped: int = 0  # 已存在（幂等跳过）
    failed: int = 0  # 解析失败
    errors: list[str] = field(default_factory=list)


def _match_file(path: Path, date_str: str | None, report_type: str | None) -> bool:
    """按文件名判断是否属于本次导入范围。"""
    m = _REPORT_FILE_RE.search(path.name)
    if not m:
        return False
    if report_type is not None and m.group(1) != report_type:
        return False
    return date_str is None or date_str in path.name


def import_history(
    report_dir: str | Path,
    date_str: str | None = None,
    report_type: str | None = None,
    *,
    force: bool = False,
) -> ImportStats:
    """扫描 {report_dir}/{YYYYMMDD}/ 下全部 `*_news_daily_*.html` 并入库。

    - 幂等：主表唯一键 (report_date, report_type, file_name) 已存在则跳过；
    - `force=True` 时跳过存在性检查，直接覆盖重导；
    - 单文件解析失败不影响其他文件。
    """
    stats = ImportStats()
    root = Path(report_dir)
    if not root.is_dir():
        logger.error("日报目录不存在: {}", root)
        raise FileNotFoundError(f"日报目录不存在: {root}")

    files = sorted(p for p in root.glob("*/[a-z]*_news_daily_*.html") if _match_file(p, date_str, report_type))
    stats.scanned = len(files)
    logger.info("扫描到日报文件 {} 份: {}", stats.scanned, root)

    conn = connect()
    try:
        for path in files:
            try:
                html = path.read_text(encoding="utf-8")
                report = parse_report(html, path.name)
            except ReportParseError as e:
                stats.failed += 1
                stats.errors.append(f"{path.name}: {e}")
                logger.warning("解析失败: {} ({})", path.name, e)
                continue
            except Exception as e:  # 防御未知异常，不中断批量
                stats.failed += 1
                stats.errors.append(f"{path.name}: {type(e).__name__}: {e}")
                logger.exception("读取/解析异常: {}", path.name)
                continue

            if not force and exists_report(conn, report.report_date, report.report_type, report.file_name):
                stats.skipped += 1
                logger.debug("已存在, 跳过: {}", path.name)
                continue
            save_report(conn, report)
            stats.imported += 1
    finally:
        conn.close()

    logger.info("导入完成: scanned={} imported={} skipped={} failed={}",
                stats.scanned, stats.imported, stats.skipped, stats.failed)
    return stats