/**
 * 订单状态同步定时任务 API
 * GET /api/cron/sync-orders?secret=YOUR_SECRET
 * 
 * 功能：
 * 1. 查询 'created' 状态的订单
 * 2. 调用微信支付接口查询真实状态
 * 3. 同步订单状态（paid / expired）
 * 4. 更新用户购买记录
 * 
 * 部署方式：
 * - 方式1: 使用 cron 定时调用此接口（推荐）
 * - 方式2: 使用 Vercel Cron（如果部署在 Vercel）
 * - 方式3: 使用 node-cron 在服务端定时执行
 */

import { NextRequest, NextResponse } from 'next/server'
import { query } from '@/lib/db'
import crypto from 'crypto'

// 触发同步的密钥（写死，仅用于防止误触，非高安全场景）
const CRON_SECRET = 'soul_cron_sync_orders_2026'

// 微信支付配置
const WECHAT_PAY_CONFIG = {
  appid: process.env.WECHAT_APPID || 'wxb8bbb2b10dec74aa',
  mchId: process.env.WECHAT_MCH_ID || '1318592501',
  apiKey: process.env.WECHAT_API_KEY || '', // 需要配置真实的 API Key
}

// 订单超时时间（分钟）
const ORDER_TIMEOUT_MINUTES = 30

/**
 * 生成随机字符串
 */
function generateNonceStr(length: number = 32): string {
  const chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789'
  let result = ''
  for (let i = 0; i < length; i++) {
    result += chars.charAt(Math.floor(Math.random() * chars.length))
  }
  return result
}

/**
 * 生成微信支付签名
 */
function createSign(params: Record<string, any>, apiKey: string): string {
  // 1. 参数排序
  const sortedKeys = Object.keys(params).sort()
  
  // 2. 拼接字符串
  const stringA = sortedKeys
    .filter(key => params[key] !== undefined && params[key] !== '')
    .map(key => `${key}=${params[key]}`)
    .join('&')
  
  const stringSignTemp = `${stringA}&key=${apiKey}`
  
  // 3. MD5 加密并转大写
  return crypto.createHash('md5').update(stringSignTemp, 'utf8').digest('hex').toUpperCase()
}

/**
 * 查询微信支付订单状态
 */
async function queryWechatOrderStatus(outTradeNo: string): Promise<string> {
  const url = 'https://api.mch.weixin.qq.com/pay/orderquery'
  
  const params = {
    appid: WECHAT_PAY_CONFIG.appid,
    mch_id: WECHAT_PAY_CONFIG.mchId,
    out_trade_no: outTradeNo,
    nonce_str: generateNonceStr(),
  }
  
  // 生成签名
  const sign = createSign(params, WECHAT_PAY_CONFIG.apiKey)
  
  // 构建 XML 请求体
  let xmlData = '<xml>'
  Object.entries({ ...params, sign }).forEach(([key, value]) => {
    xmlData += `<${key}>${value}</${key}>`
  })
  xmlData += '</xml>'
  
  try {
    const response = await fetch(url, {
      method: 'POST',
      headers: { 'Content-Type': 'application/xml' },
      body: xmlData,
    })
    
    const respText = await response.text()
    
    // 简单解析 XML（生产环境建议用专业库）
    if (respText.includes('<return_code><![CDATA[SUCCESS]]></return_code>')) {
      if (respText.includes('<trade_state><![CDATA[SUCCESS]]></trade_state>')) {
        return 'SUCCESS'
      } else if (respText.includes('<trade_state><![CDATA[NOTPAY]]></trade_state>')) {
        return 'NOTPAY'
      } else if (respText.includes('<trade_state><![CDATA[CLOSED]]></trade_state>')) {
        return 'CLOSED'
      } else if (respText.includes('<trade_state><![CDATA[REFUND]]></trade_state>')) {
        return 'REFUND'
      }
    }
    
    return 'UNKNOWN'
    
  } catch (error) {
    console.error('[SyncOrders] 查询微信订单失败:', error)
    return 'ERROR'
  }
}

/**
 * 主函数：同步订单状态
 */
export async function GET(request: NextRequest) {
  const startTime = Date.now()
  
  // 1. 验证密钥
  const { searchParams } = new URL(request.url)
  const secret = searchParams.get('secret')
  
  if (secret !== CRON_SECRET) {
    return NextResponse.json({
      success: false,
      error: '未授权访问'
    }, { status: 401 })
  }
  
  console.log('[SyncOrders] ========== 订单状态同步任务开始 ==========')
  
  try {
    // 2. 查询所有 'created' 状态的订单（最近 2 小时内）
    const twoHoursAgo = new Date(Date.now() - 2 * 60 * 60 * 1000)
    
    const pendingOrders = await query(`
      SELECT id, order_sn, user_id, product_type, product_id, amount, created_at
      FROM orders 
      WHERE status = 'created' AND created_at >= ?
      ORDER BY created_at DESC
    `, [twoHoursAgo]) as any[]
    
    if (pendingOrders.length === 0) {
      console.log('[SyncOrders] 没有需要同步的订单')
      return NextResponse.json({
        success: true,
        message: '没有需要同步的订单',
        synced: 0,
        expired: 0,
        duration: Date.now() - startTime
      })
    }
    
    console.log(`[SyncOrders] 找到 ${pendingOrders.length} 个待同步订单`)
    
    let syncedCount = 0
    let expiredCount = 0
    let errorCount = 0
    
    for (const order of pendingOrders) {
      const orderSn = order.order_sn
      const createdAt = new Date(order.created_at)
      const timeDiff = Date.now() - createdAt.getTime()
      const minutesDiff = Math.floor(timeDiff / (1000 * 60))
      
      // 3. 判断订单是否超时
      if (minutesDiff > ORDER_TIMEOUT_MINUTES) {
        console.log(`[SyncOrders] 订单 ${orderSn} 超时 (${minutesDiff} 分钟)，标记为 expired`)
        
        await query(`
          UPDATE orders 
          SET status = 'expired', updated_at = NOW()
          WHERE order_sn = ?
        `, [orderSn])
        
        expiredCount++
        continue
      }
      
      // 4. 查询微信支付状态（需要配置 API Key）
      if (!WECHAT_PAY_CONFIG.apiKey) {
        console.log(`[SyncOrders] 跳过订单 ${orderSn}（未配置 API Key）`)
        continue
      }
      
      const wechatStatus = await queryWechatOrderStatus(orderSn)
      
      if (wechatStatus === 'SUCCESS') {
        // 微信支付成功，更新为 paid
        console.log(`[SyncOrders] 订单 ${orderSn} 微信支付成功，更新为 paid`)
        
        await query(`
          UPDATE orders 
          SET status = 'paid', updated_at = NOW()
          WHERE order_sn = ?
        `, [orderSn])
        
        // 更新用户购买记录
        if (order.product_type === 'fullbook') {
          await query(`
            UPDATE users 
            SET has_full_book = 1
            WHERE id = ?
          `, [order.user_id])
        }
        
        syncedCount++
        
      } else if (wechatStatus === 'NOTPAY') {
        console.log(`[SyncOrders] 订单 ${orderSn} 尚未支付`)
        
      } else if (wechatStatus === 'CLOSED') {
        console.log(`[SyncOrders] 订单 ${orderSn} 已关闭，标记为 cancelled`)
        
        await query(`
          UPDATE orders 
          SET status = 'cancelled', updated_at = NOW()
          WHERE order_sn = ?
        `, [orderSn])
        
      } else {
        console.log(`[SyncOrders] 订单 ${orderSn} 查询失败: ${wechatStatus}`)
        errorCount++
      }
    }
    
    const duration = Date.now() - startTime
    
    console.log(`[SyncOrders] 同步完成: 同步 ${syncedCount} 个，超时 ${expiredCount} 个，失败 ${errorCount} 个`)
    console.log(`[SyncOrders] ========== 任务结束 (耗时 ${duration}ms) ==========`)
    
    return NextResponse.json({
      success: true,
      message: '订单状态同步完成',
      total: pendingOrders.length,
      synced: syncedCount,
      expired: expiredCount,
      error: errorCount,
      duration
    })
    
  } catch (error) {
    console.error('[SyncOrders] 同步失败:', error)
    
    return NextResponse.json({
      success: false,
      error: '订单状态同步失败',
      detail: error instanceof Error ? error.message : String(error)
    }, { status: 500 })
  }
}