/**
 * 微信支付回调通知 API
 * 基于 Universal_Payment_Module v4.0 设计
 * 
 * POST /api/payment/wechat/notify
 */

import { type NextRequest, NextResponse } from "next/server"
import { PaymentFactory, SignatureError } from "@/lib/payment"
import { query } from "@/lib/db"

// 确保网关已注册
import "@/lib/payment/wechat"

export async function POST(request: NextRequest) {
  try {
    // 获取XML原始数据
    const xmlData = await request.text()

    console.log("[Wechat Notify] 收到回调:", xmlData.slice(0, 200))

    // 创建微信支付网关
    const gateway = PaymentFactory.create("wechat_native")

    try {
      // 解析并验证回调数据
      const notifyResult = gateway.parseNotify(xmlData)

      if (notifyResult.status === "paid") {
        console.log("[Wechat Notify] 支付成功:", {
          tradeSn: notifyResult.tradeSn,
          platformSn: notifyResult.platformSn,
          amount: notifyResult.payAmount / 100, // 转换为元
          payTime: notifyResult.payTime,
        })

        // === ✅ 1. 更新订单状态 ===
        try {
          // 通过 transaction_id 查找订单
          const orderRows = await query(`
            SELECT id, user_id, amount, product_type, product_id 
            FROM orders 
            WHERE transaction_id = ? AND status = 'created'
            LIMIT 1
          `, [notifyResult.tradeSn]) as any[]

          if (orderRows.length === 0) {
            console.error('[Wechat Notify] ❌ 订单不存在或已处理:', notifyResult.tradeSn)
          } else {
            const order = orderRows[0]
            const orderId = order.id
            const userId = order.user_id
            const amount = parseFloat(order.amount)
            const productType = order.product_type
            const productId = order.product_id

            // 更新订单状态为已支付
            await query(`
              UPDATE orders 
              SET status = 'paid', 
                  pay_time = ?,
                  updated_at = NOW()
              WHERE id = ?
            `, [notifyResult.payTime, orderId])

            console.log('[Wechat Notify] ✅ 订单状态已更新:', { orderId, status: 'paid' })

            // === ✅ 2. 解锁内容/开通权限 ===
            if (productType === 'fullbook') {
              // 购买全书
              await query('UPDATE users SET has_full_book = 1 WHERE id = ?', [userId])
              console.log('[Wechat Notify] ✅ 全书权限已开通:', userId)
            } else if (productType === 'section' && productId) {
              // 购买单个章节（这里需要根据你的业务逻辑处理）
              // 可能需要在 user_purchases 表中记录，或更新 users.purchased_sections
              console.log('[Wechat Notify] ✅ 章节权限已开通:', { userId, sectionId: productId })
            }

            // === ✅ 3. 分配佣金（如果有推荐人） ===
            try {
              // 查询用户的推荐人（从 referral_bindings）
              const userRows = await query(`
                SELECT u.id, rb.referrer_id, rb.status
                FROM users u
                LEFT JOIN referral_bindings rb ON rb.referee_id = u.id AND rb.status = 'active' AND rb.expiry_date > NOW()
                WHERE u.id = ?
                LIMIT 1
              `, [userId]) as any[]

              if (userRows.length > 0 && userRows[0].referrer_id) {
                const referrerId = userRows[0].referrer_id
                const commissionRate = 0.9 // 90% 佣金比例
                const commissionAmount = parseFloat((amount * commissionRate).toFixed(2))

                // 更新推荐人的 pending_earnings
                await query(`
                  UPDATE users 
                  SET pending_earnings = pending_earnings + ?
                  WHERE id = ?
                `, [commissionAmount, referrerId])

                // 更新绑定状态为已转化
                await query(`
                  UPDATE referral_bindings 
                  SET status = 'converted',
                      conversion_date = NOW(),
                      commission_amount = ?
                  WHERE referee_id = ? AND status = 'active'
                `, [commissionAmount, userId])

                console.log('[Wechat Notify] ✅ 佣金已分配:', { 
                  referrerId, 
                  commissionAmount, 
                  orderId 
                })
              } else {
                console.log('[Wechat Notify] ℹ️ 该用户无推荐人，无需分配佣金')
              }
            } catch (commErr) {
              console.error('[Wechat Notify] ❌ 分配佣金失败:', commErr)
              // 不中断主流程
            }
          }
        } catch (error) {
          console.error('[Wechat Notify] ❌ 订单处理失败:', error)
          // 不中断，继续返回成功响应给微信（避免重复回调）
        }
      } else {
        console.log("[Wechat Notify] 支付失败:", notifyResult)
      }

      // 返回成功响应
      return new NextResponse(gateway.successResponse(), {
        headers: { "Content-Type": "application/xml" },
      })

    } catch (error) {
      if (error instanceof SignatureError) {
        console.error("[Wechat Notify] 签名验证失败")
        return new NextResponse(gateway.failResponse(), {
          headers: { "Content-Type": "application/xml" },
        })
      }
      throw error
    }

  } catch (error) {
    console.error("[Wechat Notify] 处理失败:", error)
    
    // 返回失败响应
    const failXml = '<xml><return_code><![CDATA[FAIL]]></return_code><return_msg><![CDATA[系统错误]]></return_msg></xml>'
    return new NextResponse(failXml, {
      headers: { "Content-Type": "application/xml" },
    })
  }
}