package handler

import (
	"strconv"
	"time"

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

	"git.sundynix.cn/Blizzard/sundynix-site/server/internal/model"
	"git.sundynix.cn/Blizzard/sundynix-site/server/internal/pkg/resp"
)

// VisitHandler 访问足迹：用户端埋点 + 管理端统计。
type VisitHandler struct {
	db *gorm.DB
}

func NewVisitHandler(db *gorm.DB) *VisitHandler {
	return &VisitHandler{db: db}
}

// Track POST /api/track — 用户端埋点上报（免登录）。
// 按 (今天, ClientIP) upsert：已存在则 pv+1，否则插入 pv=1。
func (h *VisitHandler) Track(c *gin.Context) {
	ip := c.ClientIP()
	if ip == "" {
		ip = "unknown"
	}
	visit := model.Visit{
		Date: time.Now().Format("2006-01-02"),
		IP:   ip,
		PV:   1,
	}
	h.db.Clauses(clause.OnConflict{
		Columns: []clause.Column{{Name: "date"}, {Name: "ip"}},
		DoUpdates: clause.Assignments(map[string]any{
			"pv":         gorm.Expr("pv + 1"),
			"updated_at": time.Now(),
		}),
	}).Create(&visit)
	resp.OK(c, nil)
}

type dailyRow struct {
	Date string `json:"date"`
	UV   int64  `json:"uv"`
	PV   int64  `json:"pv"`
}

// Stats GET /api/admin/visits?days=30 — 近 N 天每日 UV/PV。
func (h *VisitHandler) Stats(c *gin.Context) {
	days := 30
	if v := c.Query("days"); v != "" {
		if n, err := strconv.Atoi(v); err == nil && n > 0 && n <= 365 {
			days = n
		}
	}
	since := time.Now().AddDate(0, 0, -(days - 1)).Format("2006-01-02")
	today := time.Now().Format("2006-01-02")

	var rows []dailyRow
	h.db.Model(&model.Visit{}).
		Select("date, count(*) as uv, coalesce(sum(pv), 0) as pv").
		Where("date >= ?", since).
		Group("date").
		Order("date").
		Scan(&rows)

	var totalUV, totalPV, todayUV, todayPV int64
	for _, r := range rows {
		totalUV += r.UV
		totalPV += r.PV
		if r.Date == today {
			todayUV = r.UV
			todayPV = r.PV
		}
	}

	resp.OK(c, gin.H{
		"daily":    rows,
		"total_uv": totalUV,
		"total_pv": totalPV,
		"today_uv": todayUV,
		"today_pv": todayPV,
		"days":     days,
	})
}