"""数据保留和清理任务。

根据 system_settings 中的 retention_days 配置，清理过期的海报和 PPT 文件及记录。
支持手动触发和定时调用。
"""
import logging
import os
from datetime import datetime, timedelta

from sqlalchemy import text

logger = logging.getLogger(__name__)


def cleanup_expired_data(dry_run: bool = False) -> dict:
    """清理过期数据。

    参数:
        dry_run: True 时只统计不实际删除

    返回:
        {"poster_deleted": N, "ppt_deleted": N, "files_deleted": N, "errors": [...]}
    """
    from insurance.db.compat import db
    from insurance.models.system_setting import SystemSetting

    stats = {"poster_deleted": 0, "ppt_deleted": 0, "files_deleted": 0, "errors": []}

    # 读取保留天数配置
    settings = {s.key: s.value for s in SystemSetting.query.filter(
        SystemSetting.key.in_(["poster_history_retention_days", "ppt_history_retention_days"])
    ).all()}

    poster_days = _parse_int(settings.get("poster_history_retention_days"), 365)
    ppt_days = _parse_int(settings.get("ppt_history_retention_days"), 365)

    # 清理过期海报记录
    if poster_days > 0:
        cutoff = datetime.now() - timedelta(days=poster_days)
        try:
            _cleanup_poster_records(db, cutoff, dry_run, stats)
        except Exception as e:
            stats["errors"].append(f"poster cleanup error: {e}")
            logger.error(f"海报清理失败: {e}")

    # 清理过期 PPT 历史
    if ppt_days > 0:
        cutoff = datetime.now() - timedelta(days=ppt_days)
        try:
            _cleanup_ppt_history(db, cutoff, dry_run, stats)
        except Exception as e:
            stats["errors"].append(f"ppt cleanup error: {e}")
            logger.error(f"PPT 历史清理失败: {e}")

    logger.info(f"数据清理完成: {stats}")
    return stats


def _cleanup_poster_records(db, cutoff: datetime, dry_run: bool, stats: dict):
    """清理过期海报记录和文件。"""
    from insurance.models.poster_record import PosterRecord

    expired = PosterRecord.query.filter(
        PosterRecord.created_at < cutoff,
        PosterRecord.task_status.in_(["done", "failed"]),
    ).all()

    for record in expired:
        # 删除物理文件
        if record.export_url and os.path.exists(record.export_url):
            if not dry_run:
                try:
                    os.remove(record.export_url)
                    stats["files_deleted"] += 1
                except Exception as e:
                    stats["errors"].append(f"file delete error {record.export_url}: {e}")
            else:
                stats["files_deleted"] += 1

        # 匿名化数据库记录（保留合规留痕，删除用户标识）
        if not dry_run:
            record.user_id = "deleted"
            record.export_url = None
            # 保留 prompt_used, ai_raw_content 等合规字段
        stats["poster_deleted"] += 1

    if not dry_run and expired:
        db.session.commit()


def _cleanup_ppt_history(db, cutoff: datetime, dry_run: bool, stats: dict):
    """清理过期 PPT 历史记录和文件。"""
    rows = db.session.execute(text(
        "SELECT id, file_url FROM insurance_ppt_history WHERE created_at < :cutoff"
    ), {"cutoff": cutoff}).fetchall()

    for row in rows:
        record_id, file_url = row
        # 删除物理文件
        if file_url and os.path.exists(file_url):
            if not dry_run:
                try:
                    os.remove(file_url)
                    stats["files_deleted"] += 1
                except Exception as e:
                    stats["errors"].append(f"file delete error {file_url}: {e}")
            else:
                stats["files_deleted"] += 1

        # 匿名化记录
        if not dry_run:
            db.session.execute(text(
                "UPDATE insurance_ppt_history SET user_id = 'deleted', file_url = NULL WHERE id = :id"
            ), {"id": record_id})
        stats["ppt_deleted"] += 1

    if not dry_run and rows:
        db.session.commit()

    # 清理过期 PPT 会话文件
    sessions = db.session.execute(text(
        "SELECT id, ppt_path FROM insurance_ppt_sessions "
        "WHERE created_at < :cutoff AND status = 'done'"
    ), {"cutoff": cutoff}).fetchall()

    for session_id, ppt_path in sessions:
        if ppt_path and os.path.exists(ppt_path):
            if not dry_run:
                try:
                    os.remove(ppt_path)
                    stats["files_deleted"] += 1
                except Exception as e:
                    stats["errors"].append(f"session file delete error: {e}")
            else:
                stats["files_deleted"] += 1


def _parse_int(value: str, default: int) -> int:
    try:
        return int(str(value or "").strip())
    except (TypeError, ValueError):
        return default