package middleware

import (
	"net/http"
	"strings"
	"time"

	"gotest/internal/geoip"
	"gotest/internal/model"

	"github.com/gin-gonic/gin"
	"gorm.io/gorm"
)

// responseWriter 包装 gin.ResponseWriter 以捕获状态码
type responseWriter struct {
	gin.ResponseWriter
	statusCode int
}

func (w *responseWriter) WriteHeader(code int) {
	w.statusCode = code
	w.ResponseWriter.WriteHeader(code)
}

// AccessLog 访问日志中间件，记录每次 HTTP 请求到数据库
func AccessLog(db *gorm.DB, ipService *geoip.Service) gin.HandlerFunc {
	return func(c *gin.Context) {
		// 跳过健康检查和静态资源
		path := c.Request.URL.Path
		if path == "/api/health" || strings.HasPrefix(path, "/shared/") || strings.HasPrefix(path, "/assets/") {
			c.Next()
			return
		}

		start := time.Now()
		clientIP := c.ClientIP()

		// 包装响应写入器以捕获状态码
		rw := &responseWriter{ResponseWriter: c.Writer, statusCode: http.StatusOK}
		c.Writer = rw

		c.Next()

		// 异步写入日志（不阻塞请求响应）
		go func() {
			cost := int(time.Since(start).Milliseconds())
			ua := c.Request.UserAgent()
			if len(ua) > 500 {
				ua = ua[:500]
			}
			referer := c.Request.Referer()
			if len(referer) > 500 {
				referer = referer[:500]
			}
			p := c.Request.URL.Path
			if len(p) > 500 {
				p = p[:500]
			}

			// 查询 IP 归属地
			location := ipService.Lookup(clientIP)

			log := model.AccessLog{
				IP:        clientIP,
				Path:      p,
				Method:    c.Request.Method,
				UserAgent: ua,
				Referer:   referer,
				Location:  location,
				Status:    rw.statusCode,
				Cost:      cost,
			}

			db.Create(&log)
		}()
	}
}