feat: unified gravity system - VIP members consume gravity instead of unlimited; add monthly gravity top-up cron

backend/src/modules/user/user.service.ts

@@ -46,14 +46,13 @@ export class UserService {
 
     let user = await this.userModel.findOne({ phone }).exec()
     if (!user) {
-      user = await this.userModel.create({ phone, nickname: `用户${phone.slice(-4)}` })
+      user = await this.userModel.create({ phone, nickname: `用户${phone.slice(-4)}`, gravity: 5 })
     }
 
     return this.generateAuthResponse(user)
   }
 
-  async loginByWx(code: string) {
-    // WeChat silent login - exchange code for openid
+  async loginByWx(code: string, userId?: string) {
     const appid = process.env.WX_APPID
     const secret = process.env.WX_SECRET
     if (!appid || !secret) {
@@ -70,15 +69,59 @@ export class UserService {
     }
 
     const openid = wxData.openid
+
+    if (userId) {
+      const user = await this.userModel.findById(userId).exec()
+      if (!user) throw new HttpException('用户不存在', HttpStatus.NOT_FOUND)
+      if (user.wxOpenid) throw new HttpException('该账号已绑定微信', HttpStatus.CONFLICT)
+      user.wxOpenid = openid
+      await user.save()
+      return this.generateAuthResponse(user)
+    }
+
     let user = await this.userModel.findOne({ wxOpenid: openid }).exec()
     if (!user) {
-      user = await this.userModel.create({ wxOpenid: openid, nickname: '微信用户' })
+      user = await this.userModel.create({ wxOpenid: openid, nickname: '微信用户', gravity: 5 })
     }
 
     return this.generateAuthResponse(user)
   }
 
   // 📧 邮箱验证码
+  async bindWxOpenid(userId: string, code: string) {
+    this.logger.log(`[bindWx] userId=${userId}, code=${code ? '已提供' : '空'}`)
+    const appid = process.env.WX_APPID
+    const secret = process.env.WX_SECRET
+    if (!appid || !secret) {
+      this.logger.error(`[bindWx] 微信配置不完整`)
+      throw new HttpException('微信登录未配置', HttpStatus.SERVICE_UNAVAILABLE)
+    }
+
+    const wxRes = await fetch(
+      `https://api.weixin.qq.com/sns/jscode2session?appid=${appid}&secret=${secret}&js_code=${code}&grant_type=authorization_code`,
+    )
+    const wxData: any = await wxRes.json()
+    this.logger.log(`[bindWx] 微信接口返回: ${JSON.stringify(wxData)}`)
+
+    if (wxData.errcode) {
+      this.logger.error(`[bindWx] 微信登录失败: ${wxData.errmsg}, rid: ${wxData.rid || '无'}`)
+      throw new HttpException(`微信登录失败: ${wxData.errmsg}`, HttpStatus.UNAUTHORIZED)
+    }
+
+    const openid = wxData.openid
+    this.logger.log(`[bindWx] 获取到openid=${openid}`)
+    const existing = await this.userModel.findOne({ wxOpenid: openid }).exec()
+    if (existing) {
+      this.logger.warn(`[bindWx] openid=${openid} 已绑定到其他用户 ${existing._id}`)
+      throw new HttpException('该微信号已绑定其他账号', HttpStatus.CONFLICT)
+    }
+
+    const user = await this.userModel.findByIdAndUpdate(userId, { wxOpenid: openid }, { new: true }).exec()
+    if (!user) { this.logger.error(`[bindWx] 用户不存在 userId=${userId}`); throw new HttpException('用户不存在', HttpStatus.NOT_FOUND) }
+    this.logger.log(`[bindWx] openid=${openid} 绑定到用户 ${userId} 成功`)
+    return { message: '微信绑定成功', wxOpenid: openid }
+  }
+
   async sendEmailCode(email: string) {
     if (!email || !email.includes('@')) {
       throw new HttpException('请输入正确的邮箱地址', HttpStatus.BAD_REQUEST)
@@ -113,7 +156,7 @@ export class UserService {
     if (!user) {
       isNew = true
       const nick = email.split('@')[0]
-      user = await this.userModel.create({ email, nickname: nick, remaining: 3 })
+      user = await this.userModel.create({ email, nickname: nick, remaining: 0, gravity: 5 })
     }
     return { ...this.generateAuthResponse(user), isNew, hasPassword: !!user.password }
   }
@@ -148,7 +191,7 @@ export class UserService {
     }
     const nick = email.split('@')[0]
     const hashed = await bcrypt.hash(password, 10)
-    const user = await this.userModel.create({ email, nickname: nick, password: hashed, remaining: 3 })
+    const user = await this.userModel.create({ email, nickname: nick, password: hashed, remaining: 0, gravity: 5 })
     return this.generateAuthResponse(user)
   }
 
@@ -216,6 +259,7 @@ export class UserService {
       resumeDownloadCredits: user.resumeDownloadCredits ?? 0,
       freeOptimizeUsed: user.freeOptimizeUsed ?? 0,
       shareCredits: user.shareCredits ?? 0,
+      gravity: user.gravity ?? 0,
     }
   }
 }