"""微信 Native 扫码支付（trade_type=NATIVE）。

二维码 = 微信返回的官方付款码 weixin://wxpay/bizpayurl?...
支付结果以商户回调 / 查单为准；小程序侧用轮询确认，不依赖 wx.requestPayment。
"""
from __future__ import annotations

import hashlib
import logging
import random
import string

import requests
from django.core.cache import cache

from jituan.constants import PAY_METHOD_WECHAT_NATIVE
from jituan.services.wechat_pay import (
    get_wechat_v2_config,
    log_wechat_v2_pay_diag,
    parse_wechat_v2_unifiedorder_response,
)
from utils.money import yuan_to_fen

logger = logging.getLogger(__name__)

CACHE_KEY_PREFIX = 'wx_native_code_'
SESSION_KEY_PREFIX = 'wx_native_pay_'
CACHE_TTL_SECONDS = 60 * 30


def _cache_key(dingdanid: str) -> str:
    return f'{CACHE_KEY_PREFIX}{dingdanid}'


def _session_key(dingdanid: str) -> str:
    return f'{SESSION_KEY_PREFIX}{dingdanid}'


def get_native_pay_session(dingdanid: str):
    data = cache.get(_session_key(dingdanid))
    return data if isinstance(data, dict) else None


def _native_pay_response(code_url: str) -> dict:
    from jituan.services.alipay_pay import qr_link_to_base64

    return {
        'qr_code': code_url,
        'qr_image': qr_link_to_base64(code_url),
        # 前端「复制支付链接」用同一条官方付款链接
        'pay_link': code_url,
        'pay_method': PAY_METHOD_WECHAT_NATIVE,
    }


def generate_wechat_native_pay_params(
    *,
    dingdanid,
    jine,
    body,
    notify_url,
    club_id=None,
    client_ip='127.0.0.1',
    scene='native',
):
    """统一下单 NATIVE，返回官方付款码 + 可复制链接。"""
    dingdanid = (dingdanid or '').strip()
    notify_url = (notify_url or '').strip()
    body = (body or '微信支付').strip() or '微信支付'
    if not dingdanid:
        raise Exception('订单号不能为空')
    if not notify_url:
        raise Exception('缺少微信回调地址 notify_url')

    cache.set(
        _session_key(dingdanid),
        {
            'jine': str(jine),
            'body': body,
            'notify_url': notify_url,
            'club_id': (club_id or '').strip(),
        },
        CACHE_TTL_SECONDS,
    )

    cached = cache.get(_cache_key(dingdanid)) or {}
    cached_url = (cached.get('code_url') or '').strip()
    if cached_url:
        logger.info(
            '[WX_NATIVE] reuse code_url dingdan=%s club=%s scene=%s',
            dingdanid, club_id, scene,
        )
        return _native_pay_response(cached_url)

    pay_cfg = get_wechat_v2_config(club_id)
    log_wechat_v2_pay_diag(
        pay_cfg, scene=f'native:{scene}', openid='', order_hint=dingdanid,
    )
    appid = pay_cfg.get('appid') or ''
    mch_id = pay_cfg.get('mch_id') or ''
    key = pay_cfg.get('key') or ''
    if not all([appid, mch_id, key]):
        raise Exception(
            f'微信 Native 配置不完整 club={pay_cfg.get("club_id")} '
            f'appid={bool(appid)} mch_id={bool(mch_id)} mch_key={bool(key)}'
        )

    nonce_str = ''.join(random.choices(string.ascii_letters + string.digits, k=32))
    total_fee = yuan_to_fen(jine)
    ip = (client_ip or '127.0.0.1').split(',')[0].strip() or '127.0.0.1'

    sign_data = {
        'appid': appid,
        'mch_id': mch_id,
        'nonce_str': nonce_str,
        'body': body,
        'out_trade_no': dingdanid,
        'total_fee': total_fee,
        'spbill_create_ip': ip,
        'notify_url': notify_url,
        'trade_type': 'NATIVE',
    }
    sorted_items = sorted(sign_data.items(), key=lambda x: x[0])
    sign_string = '&'.join(f'{k}={v}' for k, v in sorted_items if v) + f'&key={key}'
    sign = hashlib.md5(sign_string.encode('utf-8')).hexdigest().upper()

    xml_data = f"""<xml>
<appid>{appid}</appid>
<body>{body}</body>
<mch_id>{mch_id}</mch_id>
<nonce_str>{nonce_str}</nonce_str>
<notify_url>{notify_url}</notify_url>
<out_trade_no>{dingdanid}</out_trade_no>
<spbill_create_ip>{ip}</spbill_create_ip>
<total_fee>{total_fee}</total_fee>
<trade_type>NATIVE</trade_type>
<sign>{sign}</sign>
</xml>"""

    response = requests.post(
        'https://api.mch.weixin.qq.com/pay/unifiedorder',
        data=xml_data.encode('utf-8'),
        headers={'Content-Type': 'application/xml'},
        timeout=10,
    )
    parsed = parse_wechat_v2_unifiedorder_response(
        response.content,
        log_prefix=f'WX_NATIVE_{scene}',
        expect='code_url',
    )
    code_url = parsed['code_url']
    cache.set(_cache_key(dingdanid), {'code_url': code_url}, CACHE_TTL_SECONDS)
    logger.warning(
        '[WX_NATIVE] unifiedorder ok dingdan=%s club=%s mch=%s scene=%s',
        dingdanid, pay_cfg.get('club_id'), mch_id, scene,
    )
    return _native_pay_response(code_url)


# 旧 H5 / 小程序码落地页仍可能 import，保留最小兼容，避免 ImportError
def build_native_bridge_url(dingdanid: str, club_id=None) -> str:
    from urllib.parse import quote
    q = f'out_trade_no={quote(dingdanid or "", safe="")}'
    if club_id:
        q += f'&club_id={quote(str(club_id), safe="")}'
    return f'https://www.abas.asia/hqhd/dingdan/wx-native-pay/?{q}'


def build_official_jsapi_pay_params(
    *,
    dingdanid,
    jine,
    body,
    notify_url='',
    openid,
    club_id=None,
    client_ip='127.0.0.1',
):
    """服务号 JSAPI 统一下单（H5 / 相册中转页）。notify_url 由订单侧 settings 接管。"""
    from orders.views.payment import CreateOrderView

    helper = CreateOrderView()
    return helper.generate_wechat_pay_params(
        dingdanid=dingdanid,
        jine=jine,
        beizhu=(body or '微信支付')[:40] or '微信支付',
        user_ip=client_ip or '127.0.0.1',
        openid=openid,
        club_id=club_id,
        app_source='official',
    )


def build_mini_jsapi_pay_params(**kwargs):
    raise Exception('小程序请走 CreateOrderView.generate_wechat_pay_params(app_source=mini)')


def build_h5_jsapi_bridge_url(dingdanid: str, club_id=None, return_url='') -> str:
    from urllib.parse import quote
    q = f'out_trade_no={quote(dingdanid or "", safe="")}'
    if club_id:
        q += f'&club_id={quote(str(club_id), safe="")}'
    if return_url:
        q += f'&return_url={quote(str(return_url), safe="")}'
    return f'https://www.abas.asia/hqhd/dingdan/wx-h5-pay/?{q}'


def resolve_scene_to_dingdanid(scene: str) -> str:
    return ''