package handler

import (
	"crypto/rand"
	"encoding/hex"
	"fmt"
	"net/http"

	"github.com/freefire/jiang13-bbs/middleware"
	"github.com/freefire/jiang13-bbs/service"
	"github.com/gin-gonic/gin"
)

const visitorCookie = "j13_vid"

func newVisitorID() string {
	var b [16]byte
	_, _ = rand.Read(b[:])
	// 伪 UUID 形态，满足 ValidVisitorID
	return fmt.Sprintf("%s-%s-%s-%s-%s",
		hex.EncodeToString(b[0:4]),
		hex.EncodeToString(b[4:6]),
		hex.EncodeToString(b[6:8]),
		hex.EncodeToString(b[8:10]),
		hex.EncodeToString(b[10:16]),
	)
}

// POST /api/telemetry/pageview — 轻量 PV/UV 埋点（公开，需 CSRF）
func (h *Handlers) TelemetryPageView(c *gin.Context) {
	vid, _ := c.Cookie(visitorCookie)
	if !service.ValidVisitorID(vid) {
		vid = newVisitorID()
		secure := c.Request.TLS != nil || c.GetHeader("X-Forwarded-Proto") == "https"
		// HttpOnly：仅服务端读 UV，前端埋点不依赖可读 cookie
		c.SetCookie(visitorCookie, vid, 365*24*3600, "/", "", secure, true)
	}

	loggedIn := middleware.CurrentUser(c) != nil
	if err := h.Telemetry.RecordPageView(vid, loggedIn); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "记录失败"})
		return
	}
	c.JSON(http.StatusOK, gin.H{"ok": true})
}

// GET /api/admin/analytics/overview?range=7d|30d
func (h *Handlers) AdminAnalyticsOverview(c *gin.Context) {
	rangeQ := c.DefaultQuery("range", "7d")
	data, err := h.Analytics.Overview(rangeQ)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "获取分析数据失败"})
		return
	}
	c.JSON(http.StatusOK, data)
}