"""
打手注册共用逻辑：邀请码解析、创建打手、管事邀请统计。
"""
import logging

from django.conf import settings
from django.db import transaction

from yonghu.models import UserDashou, UserGuanshi, UserMain

logger = logging.getLogger('yonghu.dashouzhuce')


def get_default_dashou_invite_code():
    return getattr(settings, 'DASHOU_DEFAULT_INVITE_CODE', '').strip()


def mark_guanshi_qr_scanned(user_main, invite_code_raw):
    """
    仅当请求明确带了管事邀请码（真实扫码）时，标记用户已扫过管事二维码。
    空邀请码走默认码注册的不标记，避免误开隐藏商品。
    已是打手/老用户同样必须写入，注册流程可跳过，标记不可跳过。
    """
    if not user_main or not (invite_code_raw or '').strip():
        return False
    updated = UserMain.objects.filter(pk=user_main.pk).exclude(guanshi_saoma=1).update(guanshi_saoma=1)
    user_main.guanshi_saoma = 1
    if updated:
        logger.info(
            '扫管事码标记已写入 yonghuid=%s invite=%s',
            getattr(user_main, 'yonghuid', ''),
            (invite_code_raw or '')[:20],
        )
    return True


def resolve_guanshi_for_dashou_register(invite_code):
    """
    根据邀请码查找管事；无邀请码时使用默认码；默认码查不到时按平台管事 yonghuid 回退。
    返回 (guanshi_profile, error_message)
    """
    code = (invite_code or '').strip()
    default_code = get_default_dashou_invite_code()
    if not code:
        code = default_code
    if not code:
        return None, '邀请码不能为空'
    if len(code) > 100:
        return None, '邀请码长度超过限制'

    guanshi = UserGuanshi.objects.select_related('user').filter(yaoqingma=code).first()
    if guanshi:
        return guanshi, None

    if default_code and code == default_code:
        fallback_uid = getattr(settings, 'DASHOU_DEFAULT_GUANSHI_YONGHUID', '').strip()
        if fallback_uid:
            guanshi = UserGuanshi.objects.select_related('user').filter(
                user__yonghuid=fallback_uid,
            ).first()
            if guanshi:
                if guanshi.yaoqingma != code:
                    UserGuanshi.objects.filter(pk=guanshi.pk).update(yaoqingma=code)
                    guanshi.refresh_from_db()
                logger.info('默认邀请码回退到平台管事 yonghuid=%s', fallback_uid)
                return guanshi, None

    return None, '邀请码无效或不存在'


def create_dashou_for_user(user_main, guanshi_profile):
    """为已登录用户创建打手身份，并更新管事邀请统计。返回 dashou_profile。"""
    try:
        return user_main.dashou_profile
    except UserDashou.DoesNotExist:
        pass

    guanshi_yonghuid = guanshi_profile.user.yonghuid
    with transaction.atomic():
        dashou_profile = UserDashou.objects.create(
            user=user_main,
            nicheng='大手子',
            chenghao='普通大手',
            yaoqingren=guanshi_yonghuid,
            jifen=5,
        )
        locked_guanshi = UserGuanshi.objects.select_for_update().get(pk=guanshi_profile.pk)
        locked_guanshi.yaogingshuliang += 1
        locked_guanshi.save(update_fields=['yaogingshuliang'])

    try:
        from decimal import Decimal
        from houtai.utils import update_guanshi_daily_by_action
        update_guanshi_daily_by_action(
            yonghuid=guanshi_yonghuid,
            action=1,
            amount=Decimal('0.00'),
        )
    except Exception as stat_err:
        logger.warning('管事每日统计更新失败（邀请打手）：%s', stat_err)

    return dashou_profile


def ensure_guanshi_profile_for_user(user_main):
    """扫码注册流程：若用户尚无管事身份则创建（已存在则跳过）。"""
    if UserGuanshi.objects.filter(user=user_main).exists():
        return UserGuanshi.objects.get(user=user_main)

    from utils.yaoqingma_utils import chuangjianYaoqingma
    return UserGuanshi.objects.create(
        user=user_main,
        yaoqingma=chuangjianYaoqingma(str(user_main.yonghuid)),
    )