package ipstat

import (
	"net"
	"time"
	"videoweb/pub/common/enum/redisconst"
	"videoweb/pub/common/ipaddr"
	"videoweb/pub/common/log"
	"videoweb/pub/common/utils"
	"videoweb/pub/pubdef"
	"videoweb/pub/redis"

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

func IpStatMiddleware(ctx *gin.Context) {
	ctx.Next()

	normalized := normalizeIP(ipaddr.ResolveClientIP(ctx))
	if normalized == "" {
		return
	}

	date := time.Now().In(utils.LocBJ).Format("20060102")
	key := redisconst.IpStatKey(pubdef.AppId, date)

	added, err := redis.SAddCount(key, normalized)
	if err != nil {
		log.Warn("IpStatMiddleware SAdd failed", log.Any("key", key), log.E(err))
		return
	}
	if added > 0 {
		if err := redis.Expire(key, redisconst.IpStatExpire); err != nil {
			log.Warn("IpStatMiddleware Expire failed", log.Any("key", key), log.E(err))
		}
	}
}

func normalizeIP(raw string) string {
	ip := net.ParseIP(raw)
	if ip == nil {
		return ""
	}
	if v4 := ip.To4(); v4 != nil {
		ip = v4
	}
	if isPrivateIP(ip) {
		return ""
	}
	return ip.String()
}

var privateRanges = []net.IPNet{
	parseCIDR("10.0.0.0/8"),
	parseCIDR("172.16.0.0/12"),
	parseCIDR("192.168.0.0/16"),
	parseCIDR("127.0.0.0/8"),
	parseCIDR("::1/128"),
	parseCIDR("fe80::/10"),
	parseCIDR("fc00::/7"),
}

func parseCIDR(s string) net.IPNet {
	_, network, err := net.ParseCIDR(s)
	if err != nil {
		panic(err)
	}
	return *network
}

func isPrivateIP(ip net.IP) bool {
	for _, r := range privateRanges {
		if r.Contains(ip) {
			return true
		}
	}
	return false
}