package hvpnnode3

import (
	"fmt"
	"log/slog"
	"strings"
	"time"

	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
)

var log slog.Logger

func StartMonitor(wg *WGLink, log slog.Logger) {
    go monitor(wg, log)
}

func monitor(wg *WGLink, log slog.Logger) {
    log.Info("[WGMonitor] Starting")
    for {
        time.Sleep(time.Second * 10)
        peers, err := wg.GetAllPeers()
        if err != nil {
            log.Error("[WGMonitor] " + err.Error())
            continue
        }

        sb := strings.Builder{}
        var activePeers int
        var totalRx int64
        var totalTx int64
        for _, peer := range peers {
            totalRx += peer.ReceiveBytes
            totalTx += peer.TransmitBytes
            if isActive(peer) {
                activePeers += 1
            }
        }
        sb.WriteString(fmt.Sprintf("Peers: %d ", len(peers)))
        sb.WriteString(fmt.Sprintf("Active peers: %d ", activePeers))
        sb.WriteString(fmt.Sprintf("TX: %d RX: %d", totalTx, totalRx))

        log.Info("[WGMonitor] " + sb.String())
    }
}

func isActive(peer wgtypes.Peer) bool {
    if peer.LastHandshakeTime.IsZero() {
        return false
    } else if time.Since(peer.LastHandshakeTime.UTC()) < time.Duration(4 * time.Minute) {
        return true
    }
    return false
}