"""操作审计日志工具：记录关键业务操作。"""
from flask import request
from insurance.db.compat import db
from insurance.models.operation_log import SystemOperationLog


def log_operation(user_id: str, action: str, target_type: str = "",
                  target_id: str = "", detail: dict = None):
    """写入一条操作日志。

    Args:
        user_id: 操作人 ID
        action: 操作类型（login/logout/create/update/delete/export/share 等）
        target_type: 操作对象类型（user/proposal/document/datasource 等）
        target_id: 操作对象 ID
        detail: 附加信息
    """
    try:
        log = SystemOperationLog(
            user_id=str(user_id),
            action=action,
            target_type=target_type,
            target_id=str(target_id),
            detail=detail or {},
            ip=request.remote_addr if request else "",
            user_agent=str(request.user_agent)[:256] if request else "",
        )
        db.session.add(log)
        db.session.commit()
    except Exception:
        db.session.rollback()


def log_config_change(user_id: str, target_type: str, target_id: str,
                      old_value: dict = None, new_value: dict = None):
    """记录配置变更日志（含变更前后值）。

    Args:
        user_id: 操作人 ID
        target_type: 配置类型（prompt/template/llm_config/notification 等）
        target_id: 配置ID
        old_value: 变更前的值
        new_value: 变更后的值
    """
    detail = {
        "old_value": old_value or {},
        "new_value": new_value or {},
        "changes": _get_changes(old_value or {}, new_value or {}),
    }
    log_operation(user_id, "update", target_type, target_id, detail)


def _get_changes(old: dict, new: dict) -> list:
    """比较两个字典，返回变更列表。"""
    changes = []
    all_keys = set(list(old.keys()) + list(new.keys()))

    for key in all_keys:
        old_val = old.get(key)
        new_val = new.get(key)

        if old_val != new_val:
            changes.append({
                "field": key,
                "old": old_val,
                "new": new_val,
            })

    return changes