package main

import (
	"fmt"
	"io/ioutil"
	"net"
	//"os"
	"path/filepath"
	//"strings"

	"github.com/charmbracelet/lipgloss"
	"github.com/vishvananda/netlink"
	"github.com/vishvananda/netns"
	"golang.org/x/sys/unix"
)

func main() {
	headerStyle := lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("63"))
	ipStyle := lipgloss.NewStyle().Foreground(lipgloss.Color("203"))
	upStyle := lipgloss.NewStyle().Foreground(lipgloss.Color("42"))
	downStyle := lipgloss.NewStyle().Foreground(lipgloss.Color("196"))
	addrStyle := lipgloss.NewStyle().Faint(true)
	infoStyle := lipgloss.NewStyle().Foreground(lipgloss.Color("33"))

	// Save the current netns
	origNS, err := netns.Get()
	if err != nil {
		fmt.Println("Error getting current netns:", err)
		return
	}
	defer origNS.Close()

	links, err := netlink.LinkList()
	if err != nil {
		fmt.Println("Error listing links:", err)
		return
	}

	for _, link := range links {
		attrs := link.Attrs()
		if attrs == nil {
			continue
		}

		state := downStyle.Render("DOWN")
		if attrs.Flags&net.FlagUp != 0 {
			state = upStyle.Render("UP")
		}

		fmt.Print(headerStyle.Render(attrs.Name), " ")
		fmt.Printf(addrStyle.Render(" %s"), attrs.HardwareAddr)
		fmt.Printf(addrStyle.Render(" %d"), attrs.MTU)
		fmt.Printf(" %s\n", state)

		// IP addresses (IPv4 only)
		addrs, err := netlink.AddrList(link, unix.AF_INET)
		if err == nil {
			for _, addr := range addrs {
				fmt.Println("  ", ipStyle.Render(addr.IPNet.String()))
			}
		}

		if link.Type() != "veth" {
			fmt.Println()
			continue
		}

		fmt.Println("  ", infoStyle.Render("Veth interface"))

		// Try to find peer locally
		peerFound := false
		for _, other := range links {
			if other.Attrs().Index == attrs.Index {
				continue
			}
			if other.Type() == "veth" && other.Attrs().ParentIndex == attrs.Index {
				fmt.Println("  ", infoStyle.Render("Likely peer:"), other.Attrs().Name)
				peerFound = true
				break
			}
		}

		// If not found, scan /var/run/netns/
		if !peerFound {
			netnsDir := "/var/run/netns/"
			entries, err := ioutil.ReadDir(netnsDir)
			if err != nil {
				fmt.Println("  ", infoStyle.Render("Could not scan netns dir"))
			} else {
				for _, entry := range entries {
					nsPath := filepath.Join(netnsDir, entry.Name())

					nsHandle, err := netns.GetFromPath(nsPath)
					if err != nil {
						continue
					}

					if err := netns.Set(nsHandle); err != nil {
						nsHandle.Close()
						continue
					}

					remoteLinks, err := netlink.LinkList()
					if err == nil {
						for _, rl := range remoteLinks {
							if rl.Type() == "veth" && rl.Attrs().ParentIndex == attrs.Index {
								fmt.Println("  ", infoStyle.Render("Peer in namespace:"), entry.Name(), "as", rl.Attrs().Name)
								peerFound = true
								break
							}
						}
					}
					nsHandle.Close()
					netns.Set(origNS)

					if peerFound {
						break
					}
				}
			}
		}

		if !peerFound {
			fmt.Println("  ", infoStyle.Render("Peer not found — may be deleted or hidden"))
		}

		fmt.Println()
	}
}