from alipay import AliPay
from flask import current_app
import os
import logging

logger = logging.getLogger(__name__)

class AlipayService:
    def __init__(self):
        self.app_id = current_app.config.get('ALIPAY_APP_ID')
        self.private_key = current_app.config.get('ALIPAY_APP_PRIVATE_KEY')
        self.public_key = current_app.config.get('ALIPAY_PUBLIC_KEY')
        self.return_url = current_app.config.get('ALIPAY_RETURN_URL')
        self.notify_url = current_app.config.get('ALIPAY_NOTIFY_URL')
        self.debug = current_app.config.get('ALIPAY_DEBUG', True)

    def get_alipay_client(self):
        """获取支付宝客户端实例"""
        return AliPay(
            appid=self.app_id,
            app_notify_url=self.notify_url,
            app_private_key_string=self.private_key,
            alipay_public_key_string=self.public_key,
            sign_type="RSA2",
            debug=self.debug
        )

    def create_order_url(self, out_trade_no, total_amount, subject):
        """生成支付链接 (电脑网站支付)"""
        alipay = self.get_alipay_client()
        order_string = alipay.api_alipay_trade_page_pay(
            out_trade_no=out_trade_no,
            total_amount=str(total_amount),
            subject=subject,
            return_url=self.return_url,
            notify_url=self.notify_url
        )
        # 拼接支付网关 (使用最新的支付宝沙箱域名)
        gateway = "https://openapi-sandbox.dl.alipaydev.com/gateway.do" if self.debug else "https://openapi.alipay.com/gateway.do"
        return f"{gateway}?{order_string}"

    def verify_notify(self, data, signature):
        """验证通知签名"""
        try:
            logger.info(f"开始验证支付宝签名，数据: {data}")
            logger.info(f"签名值: {signature}")
            
            # 验证必要参数
            if not signature:
                logger.error("签名为空")
                return False
            
            if not data:
                logger.error("数据为空")
                return False
            
            # 创建数据副本，避免修改原数据
            verify_data = data.copy()
            
            # 移除sign和sign_type，这两个字段不参与验证
            verify_data.pop('sign', None)
            verify_data.pop('sign_type', None)
            
            alipay = self.get_alipay_client()
            result = alipay.verify(verify_data, signature)
            
            if result:
                logger.info("签名验证成功")
            else:
                logger.error("签名验证失败")
                logger.error(f"验证数据: {verify_data}")
                logger.error(f"公钥配置: {self.public_key[:50]}...")
                # 额外调试信息
                logger.error(f"App ID: {self.app_id}")
                logger.error(f"是否调试模式: {self.debug}")
            
            return result
            
        except Exception as e:
            logger.error(f"验证签名时发生异常: {str(e)}", exc_info=True)
            return False