num/cloudfunctions/paymentCallback/index.js

const cloud = require('wx-server-sdk');
cloud.init({ env: cloud.DYNAMIC_CURRENT_ENV });
const db = cloud.database();

// 支付成功回调（微信支付结果通知）
// 处理：能量师订阅升级 + 佣金结算
exports.main = async (event) => {
  const {
    outTradeNo,      // 订单号
    transactionId,   // 微信支付订单号
    totalFee,        // 支付金额（分）
    attach,          // 附加数据
  } = event;

  // 获取支付用户的 openId
  const { OPENID } = cloud.getWXContext();

  try {
    // 1. 查询订单是否已处理（幂等）
    const orderRes = await db.collection('orders').where({
      outTradeNo,
    }).get();

    if (orderRes.data.length > 0) {
      return { code: 0, message: '订单已处理' };
    }

    // 2. 写订单记录
    const orderData = {
      outTradeNo,
      transactionId,
      userId: OPENID,
      type: 'practitioner_annual',
      amount: totalFee,
      paymentMethod: 'wechat_pay',
      status: 'paid',
      paidAt: db.serverDate(),
      createdAt: db.serverDate(),
    };
    await db.collection('orders').add({ data: orderData });

    // 3. 更新用户为能量师（有效期 1 年）
    const now = new Date();
    const expireDate = new Date(now);
    expireDate.setFullYear(expireDate.getFullYear() + 1);

    // 查询已有用户
    const userRes = await db.collection('users').where({
      _openid: OPENID,
    }).get();

    const userData = {
      role: 'practitioner',
      practitionerExpireAt: expireDate.toISOString(),
      updatedAt: db.serverDate(),
    };

    if (userRes.data.length === 0) {
      // 新用户注册（一般不会走到这里，但以防万一）
      userData._openid = OPENID;
      userData.referralCode = generateReferralCode();
      userData.createdAt = db.serverDate();
      await db.collection('users').add({ data: userData });
    } else {
      // 已有用户，生成或保留推广码
      const user = userRes.data[0];
      if (!user.referralCode) {
        userData.referralCode = generateReferralCode();
      }
      await db.collection('users').doc(user._id).update({ data: userData });
    }

    // 4. 佣金结算：查用户的上级
    const user = (await db.collection('users').where({ _openid: OPENID }).get()).data[0];
    const invitedBy = user.invitedBy;

    if (invitedBy) {
      // 查上级是否为有效的能量师
      const parentRes = await db.collection('users').where({ _openid: invitedBy }).get();
      if (parentRes.data.length > 0) {
        const parent = parentRes.data[0];
        const isParentPractitioner = parent.practitionerExpireAt
          && new Date(parent.practitionerExpireAt).getTime() > Date.now();

        if (isParentPractitioner) {
          // 一级佣金：30%
          const level1Amount = Math.round(totalFee * 0.30);
          await db.collection('commissions').add({
            data: {
              fromUser: OPENID,
              toUser: invitedBy,
              level: 1,
              amount: level1Amount,
              sourceOrderId: outTradeNo,
              status: 'pending',
              createdAt: db.serverDate(),
              updatedAt: db.serverDate(),
            },
          });

          // 更新上级的推广统计
          const stats = parent.referralStats || {};
          await db.collection('users').doc(parent._id).update({
            data: {
              'referralStats.convertedCount': (stats.convertedCount || 0) + 1,
            },
          });

          // 查上上级（二级佣金）
          const grandParentInvitedBy = parent.invitedBy;
          if (grandParentInvitedBy) {
            const gpRes = await db.collection('users').where({ _openid: grandParentInvitedBy }).get();
            if (gpRes.data.length > 0) {
              const gp = gpRes.data[0];
              const isGpPractitioner = gp.practitionerExpireAt
                && new Date(gp.practitionerExpireAt).getTime() > Date.now();

              if (isGpPractitioner) {
                // 二级佣金：10%
                const level2Amount = Math.round(totalFee * 0.10);
                await db.collection('commissions').add({
                  data: {
                    fromUser: OPENID,
                    toUser: grandParentInvitedBy,
                    level: 2,
                    amount: level2Amount,
                    sourceOrderId: outTradeNo,
                    status: 'pending',
                    createdAt: db.serverDate(),
                    updatedAt: db.serverDate(),
                  },
                });
              }
            }
          }
        }
      }
    }

    return { code: 0, message: 'success' };
  } catch (err) {
    console.error('[paymentCallback] error:', err);
    return { code: 500, error: err.message };
  }
};

// 生成唯一6位推广码
function generateReferralCode() {
  const chars = 'ABCDEFGHJKLMNPQRSTUVWXYZ23456789';
  let code = '';
  for (let i = 0; i < 6; i++) {
    code += chars[Math.floor(Math.random() * chars.length)];
  }
  return code;
}