const jwt = require('jsonwebtoken')
const { sendVerificationCode, verifyCode } = require('../services/auth')

const JWT_SECRET = process.env.JWT_SECRET || 'your-secret-key-change-in-production'
const JWT_EXPIRES_IN = process.env.JWT_EXPIRES_IN || '7d'

const WHITELIST_CODE = process.env.WHITELIST_CODE || '888888'
const WHITELIST_EMAILS = (process.env.WHITELIST_EMAILS || '')
  .split(',').map(e => e.trim().toLowerCase()).filter(Boolean)

function createAuthRoutes(db) {
  const usersCollection = db.collection('users')

  return {
    async sendCode(req, res) {
      try {
        const { email } = req.body

        if (!email) {
          return res.status(400).json({ success: false, error: '邮箱不能为空' })
        }

        if (WHITELIST_EMAILS.includes(email.toLowerCase())) {
          return res.json({ success: true, message: '验证码已发送' })
        }

        const result = await sendVerificationCode(db, email.toLowerCase())
        
        if (!result.success) {
          return res.status(400).json(result)
        }

        res.json({ success: true, message: '验证码已发送' })
      } catch (err) {
        console.error('[Auth] Send code error:', err)
        res.status(500).json({ success: false, error: err.message })
      }
    },

    async login(req, res) {
      try {
        const { email, code, nickname } = req.body

        if (!email || !code) {
          return res.status(400).json({ success: false, error: '邮箱和验证码不能为空' })
        }

        const emailLower = email.toLowerCase()

        if (WHITELIST_EMAILS.includes(emailLower)) {
          if (code !== WHITELIST_CODE) {
            return res.status(400).json({ success: false, error: '验证码错误' })
          }
        } else {
          const verifyResult = await verifyCode(db, emailLower, code)
          if (!verifyResult.success) {
            return res.status(400).json(verifyResult)
          }
        }

        let user = await usersCollection.findOne({ email: emailLower })

        if (!user) {
          const newUser = {
            email: emailLower,
            nickname: nickname || emailLower.split('@')[0],
            avatar: null,
            created_at: new Date(),
            updated_at: new Date(),
            last_login: new Date(),
            status: 'active'
          }
          const result = await usersCollection.insertOne(newUser)
          user = { ...newUser, _id: result.insertedId }
        } else {
          await usersCollection.updateOne(
            { _id: user._id },
            { 
              $set: { 
                last_login: new Date(),
                updated_at: new Date()
              }
            }
          )
        }

        const token = jwt.sign(
          { 
            userId: user._id.toString(), 
            email: user.email 
          },
          JWT_SECRET,
          { expiresIn: JWT_EXPIRES_IN }
        )

        res.json({
          success: true,
          token,
          user: {
            id: user._id,
            email: user.email,
            nickname: user.nickname,
            avatar: user.avatar,
            created_at: user.created_at
          }
        })
      } catch (err) {
        console.error('[Auth] Login error:', err)
        res.status(500).json({ success: false, error: err.message })
      }
    },

    async verifyToken(req, res, next) {
      try {
        const authHeader = req.headers.authorization
        
        if (!authHeader || !authHeader.startsWith('Bearer ')) {
          return res.status(401).json({ success: false, error: '未登录' })
        }

        const token = authHeader.split(' ')[1]
        
        try {
          const decoded = jwt.verify(token, JWT_SECRET)
          const user = await usersCollection.findOne({ _id: new (require('mongodb').ObjectId)(decoded.userId) })
          
          if (!user) {
            return res.status(401).json({ success: false, error: '用户不存在' })
          }

          req.user = {
            id: user._id.toString(),
            email: user.email,
            nickname: user.nickname,
            avatar: user.avatar
          }
          next()
        } catch (jwtErr) {
          return res.status(401).json({ success: false, error: 'Token无效或已过期' })
        }
      } catch (err) {
        console.error('[Auth] Verify token error:', err)
        res.status(500).json({ success: false, error: err.message })
      }
    },

    async getProfile(req, res) {
      try {
        res.json({ success: true, user: req.user })
      } catch (err) {
        console.error('[Auth] Get profile error:', err)
        res.status(500).json({ success: false, error: err.message })
      }
    },

    async updateProfile(req, res) {
      try {
        const { nickname, avatar } = req.body
        const updateData = { updated_at: new Date() }
        
        if (nickname) updateData.nickname = nickname
        if (avatar) updateData.avatar = avatar

        await usersCollection.updateOne(
          { _id: new (require('mongodb').ObjectId)(req.user.id) },
          { $set: updateData }
        )

        res.json({ 
          success: true, 
          user: { ...req.user, ...updateData }
        })
      } catch (err) {
        console.error('[Auth] Update profile error:', err)
        res.status(500).json({ success: false, error: err.message })
      }
    }
  }
}

module.exports = { createAuthRoutes }