package handler

import (
	"net"
	"reflect"
	"sort"
	"testing"
	"time"

	"github.com/google/gopacket/routing"
	"github.com/libp2p/go-netroute"
	v1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
)

func TestRoute(t *testing.T) {
	var r routing.Router
	var err error
	r, err = netroute.New()
	if err != nil {
		t.Fatal(err)
	}
	iface, gateway, src, err := r.Route(net.ParseIP("8.8.8.8"))
	if err != nil {
		t.Fatal(err)
	}
	t.Logf("iface: %s, gateway: %s, src: %s", iface.Name, gateway, src)
}

func TestRemoveCIDRsContainingIPs(t *testing.T) {
	tests := []struct {
		name          string
		cidrStrings   []string
		ipStrings     []string
		expectedCIDRs []string
		expectPanic   bool
	}{
		{
			name: "Normal case - some overlaps",
			cidrStrings: []string{
				"10.140.45.0/24", "10.140.44.0/24", "10.31.0.0/24", "10.31.1.0/24", "10.31.2.0/24", "10.31.3.0/24", "10.140.47.0/24", "10.140.46.0/24",
			},
			ipStrings: []string{
				"10.140.45.1", "10.140.46.220", "10.140.45.180", "10.140.45.152",
				"10.140.46.183", "10.140.45.52", "10.140.47.148", "10.140.46.214",
			},
			expectedCIDRs: []string{
				"10.140.44.0/24", "10.31.0.0/24", "10.31.1.0/24", "10.31.2.0/24", "10.31.3.0/24",
			},
			expectPanic: false,
		},
		{
			name:        "Empty CIDR list",
			cidrStrings: []string{},
			ipStrings: []string{
				"10.140.45.1",
			},
			expectedCIDRs: []string{},
			expectPanic:   false,
		},
		{
			name: "Empty IP list",
			cidrStrings: []string{
				"10.140.45.0/24", "10.140.44.0/24",
			},
			ipStrings: []string{},
			expectedCIDRs: []string{
				"10.140.45.0/24", "10.140.44.0/24",
			},
			expectPanic: false,
		},
		{
			name: "All CIDRs removed",
			cidrStrings: []string{
				"10.140.45.0/24", "10.140.46.0/24",
			},
			ipStrings: []string{
				"10.140.45.1", "10.140.46.220",
			},
			expectedCIDRs: []string{},
			expectPanic:   false,
		},
		{
			name: "Overlapping CIDRs",
			cidrStrings: []string{
				"10.140.45.0/24", "10.140.45.0/25", "10.140.45.128/25",
			},
			ipStrings: []string{
				"10.140.45.1", "10.140.45.129",
			},
			expectedCIDRs: []string{},
			expectPanic:   false,
		},
		{
			name: "Invalid CIDR format",
			cidrStrings: []string{
				"10.140.45.0/24", "invalid-cidr",
			},
			ipStrings: []string{
				"10.140.45.1",
			},
			expectedCIDRs: nil, // Panic expected
			expectPanic:   true,
		},
	}

	for _, test := range tests {
		t.Run(test.name, func(t *testing.T) {
			defer func() {
				if r := recover(); r != nil {
					if !test.expectPanic {
						t.Errorf("unexpected panic: %v", r)
					}
				} else if test.expectPanic {
					t.Errorf("expected panic but got none")
				}
			}()

			var cidrs []*net.IPNet
			for _, cidr := range test.cidrStrings {
				_, ipNet, err := net.ParseCIDR(cidr)
				if err != nil {
					if test.expectPanic {
						panic(err)
					}
					t.Fatalf("failed to parse CIDR %s: %v", cidr, err)
				}
				cidrs = append(cidrs, ipNet)
			}

			var ipList []net.IP
			for _, ip := range test.ipStrings {
				parsedIP := net.ParseIP(ip)
				if parsedIP == nil {
					t.Fatalf("failed to parse IP %s", ip)
				}
				ipList = append(ipList, parsedIP)
			}

			c := &ConnectOptions{
				cidrs: cidrs,
			}
			c.removeCIDRsContainingIPs(ipList)
			if !test.expectPanic {
				if len(c.cidrs) != len(test.expectedCIDRs) {
					t.Fatalf("unexpected number of remaining CIDRs: got %d, want %d", len(c.cidrs), len(test.expectedCIDRs))
				}
				for i, cidr := range c.cidrs {
					if cidr.String() != test.expectedCIDRs[i] {
						t.Errorf("unexpected CIDR at index %d: got %s, want %s", i, cidr.String(), test.expectedCIDRs[i])
					}
				}
			}
		})
	}
}

func TestSort(t *testing.T) {
	list := v1.PodList{
		Items: []v1.Pod{
			{
				ObjectMeta: metav1.ObjectMeta{
					Name:              "a",
					DeletionTimestamp: nil,
				},
			},
			{
				ObjectMeta: metav1.ObjectMeta{
					Name: "b",
					DeletionTimestamp: &metav1.Time{
						Time: time.Now(),
					},
				},
			},
			{
				ObjectMeta: metav1.ObjectMeta{
					Name:              "c",
					DeletionTimestamp: nil,
				},
			},
			{
				ObjectMeta: metav1.ObjectMeta{
					Name:              "d",
					DeletionTimestamp: nil,
				},
			},
		},
	}
	sort.SliceStable(list.Items, func(i, j int) bool {
		return list.Items[i].DeletionTimestamp != nil
	})
	var names []string
	for _, item := range list.Items {
		names = append(names, item.Name)
	}
	equal := reflect.DeepEqual(names, []string{"b", "a", "c", "d"})
	if !equal {
		t.Fatal()
	}
}