# _*_ coding=utf-8 _*_
from datetime import datetime
from Crypto.PublicKey import RSA
from Crypto.Signature import PKCS1_v1_5
from Crypto.Hash import SHA256
from urllib.parse import quote_plus
from base64 import decodebytes, encodebytes
import json


class AliPay(object):
    """
    支付宝支付接口(PC端支付接口)
    """

    def __init__(self, appid, app_notify_url, app_private_key_path,
                 alipay_public_key_path, return_url, debug=False):
        self.appid = appid
        self.app_notify_url = app_notify_url
        self.app_private_key_path = app_private_key_path
        self.app_private_key = None
        self.return_url = return_url
        with open(self.app_private_key_path) as fp:
            self.app_private_key = RSA.importKey(fp.read())
        self.alipay_public_key_path = alipay_public_key_path
        with open(self.alipay_public_key_path) as fp:
            self.alipay_public_key = RSA.importKey(fp.read())

        if debug is True:
            self.__gateway = "https://openapi.alipaydev.com/gateway.do"
        else:
            self.__gateway = "https://openapi.alipay.com/gateway.do"

    def direct_pay(self, subject, out_trade_no, total_amount, return_url=None, **kwargs):
        biz_content = {
            "subject": subject,
            "out_trade_no": out_trade_no,
            "total_amount": total_amount,
            "product_code": "FAST_INSTANT_TRADE_PAY",
            # "qr_pay_mode":4
        }

        biz_content.update(kwargs)
        data = self.build_body("alipay.trade.page.pay", biz_content, self.return_url)
        return self.sign_data(data)

    def build_body(self, method, biz_content, return_url=None):
        data = {
            "app_id": self.appid,
            "method": method,
            "charset": "utf-8",
            "sign_type": "RSA2",
            "timestamp": datetime.now().strftime("%Y-%m-%d %H:%M:%S"),
            "version": "1.0",
            "biz_content": biz_content
        }

        if return_url is not None:
            data["notify_url"] = self.app_notify_url
            data["return_url"] = self.return_url

        return data

    def sign_data(self, data):
        data.pop("sign", None)
        # 排序后的字符串
        unsigned_items = self.ordered_data(data)
        unsigned_string = "&".join("{0}={1}".format(k, v) for k, v in unsigned_items)
        sign = self.sign(unsigned_string.encode("utf-8"))
        # ordered_items = self.ordered_data(data)
        quoted_string = "&".join("{0}={1}".format(k, quote_plus(v)) for k, v in unsigned_items)

        # 获得最终的订单信息字符串
        signed_string = quoted_string + "&sign=" + quote_plus(sign)
        return signed_string

    def ordered_data(self, data):
        complex_keys = []
        for key, value in data.items():
            if isinstance(value, dict):
                complex_keys.append(key)

        # 将字典类型的数据dump出来
        for key in complex_keys:
            data[key] = json.dumps(data[key], separators=(‘,‘, ‘:‘))

        return sorted([(k, v) for k, v in data.items()])

    def sign(self, unsigned_string):
        # 开始计算签名
        key = self.app_private_key
        signer = PKCS1_v1_5.new(key)
        signature = signer.sign(SHA256.new(unsigned_string))
        # base64 编码，转换为unicode表示并移除回车
        sign = encodebytes(signature).decode("utf8").replace("\n", "")
        return sign

    def _verify(self, raw_content, signature):
        # 开始计算签名
        key = self.alipay_public_key
        signer = PKCS1_v1_5.new(key)
        digest = SHA256.new()
        digest.update(raw_content.encode("utf8"))
        if signer.verify(digest, decodebytes(signature.encode("utf8"))):
            return True
        return False

    def verify(self, data, signature):
        if "sign_type" in data:
            sign_type = data.pop("sign_type")
        # 排序后的字符串
        unsigned_items = self.ordered_data(data)
        message = "&".join(u"{}={}".format(k, v) for k, v in unsigned_items)
        return self._verify(message, signature)

from django.contrib import admin
from django.urls import path
from api import views


urlpatterns = [
    path(‘admin/‘, admin.site.urls),
    path(‘index/‘, views.index),
    path(‘result/‘, views.pay_result),
    path(‘update_order/‘, views.update_order),


]

import time
from urllib.parse import parse_qs
from django.conf import settings
from django.shortcuts import render, redirect, HttpResponse
from django.views.decorators.csrf import csrf_exempt
from utils.alipay import AliPay


def aliPay():
    obj = AliPay(
        appid="2016092400581835",                              # 支付宝沙箱里面的APPID
        app_notify_url="http://127.0.0.1:8800/update_order/",  # 如果支付成功，支付宝会向这个地址发送POST请求（校验是否支付已经完成），此地址要能够在公网进行访问
        return_url="http://127.0.0.1:8800/result/",            # 如果支付成功，重定向回到你的网站的地址。
        alipay_public_key_path="keys/alipay_public_2048.txt",  # 支付宝公钥
        app_private_key_path="keys/app_private_2048.txt",      # 应用私钥
        debug=True,  # 默认False,True表示使用沙箱环境测试
    )

    # 优化:在settings里面的设置后使用
    # obj = AliPay(
    #     appid=settings.APPID,
    #     app_notify_url=settings.NOTIFY_URL,
    #     return_url=settings.RETURN_URL,
    #     alipay_public_key_path=settings.PUB_KEY_PATH,
    #     app_private_key_path=settings.PRI_KEY_PATH,
    #     debug=True,
    # )
    return obj


@csrf_exempt
def index(request):
    if request.method == "GET":
        return render(request, ‘index.html‘)

    # 实例化SDK里面的类AliPay
    alipay = aliPay()

    # 对购买的数据进行加密
    money = float(request.POST.get(‘price‘))  # 保留俩位小数
    out_trade_no = "x2" + str(time.time())  # 商户订单号
    # 1. 在数据库创建一条数据：状态（待支付）

    query_params = alipay.direct_pay(
        subject="充气式Saber",  # 商品简单描述
        out_trade_no=out_trade_no,  # 商户订单号
        total_amount=money,  # 交易金额(单位: 元 保留俩位小数)
    )
    # 拼接url，转到支付宝支付页面
    pay_url = "https://openapi.alipaydev.com/gateway.do?{}".format(query_params)

    return redirect(pay_url)


@csrf_exempt
def update_order(request):
    """
    支付成功后，支付宝向该地址发送的POST请求（用于修改订单状态）
    :param request:
    :return:
    """
    if request.method == ‘POST‘:
        body_str = request.body.decode(‘utf-8‘)
        post_data = parse_qs(body_str)

        post_dict = {}
        for k, v in post_data.items():
            post_dict[k] = v[0]

        alipay = aliPay()

        sign = post_dict.pop(‘sign‘, None)
        status = alipay.verify(post_dict, sign)
        if status:
            # 1.修改订单状态
            out_trade_no = post_dict.get(‘out_trade_no‘)
            print(out_trade_no)
            # 2. 根据订单号将数据库中的数据进行更新

            return HttpResponse(‘支付成功‘)
        else:
            return HttpResponse(‘支付失败‘)
    return HttpResponse(‘‘)


@csrf_exempt
def pay_result(request):
    """
    支付完成后，跳转回的地址
    :param request:
    :return:
    """
    params = request.GET.dict()
    sign = params.pop(‘sign‘, None)

    alipay = aliPay()

    status = alipay.verify(params, sign)

    if status:
        return HttpResponse(‘支付成功‘)
    return HttpResponse(‘支付失败‘)