//go:build linux && !android

package wgproxy

import (
	"context"
	"net"
	"testing"

	"github.com/netbirdio/netbird/client/iface/bind"
	bindproxy "github.com/netbirdio/netbird/client/iface/wgproxy/bind"
	"github.com/netbirdio/netbird/client/iface/wgproxy/ebpf"
	"github.com/netbirdio/netbird/client/iface/wgproxy/udp"

	"github.com/netbirdio/netbird/util"
)

func init() {
	_ = util.InitLog("debug", "console")
}

func TestProxyRedirect(t *testing.T) {
	ebpfProxy := ebpf.NewWGEBPFProxy(51831)
	if err := ebpfProxy.Listen(); err != nil {
		t.Fatalf("failed to initialize ebpf proxy: %s", err)
	}

	defer func() {
		if err := ebpfProxy.Free(); err != nil {
			t.Errorf("failed to free ebpf proxy: %s", err)
		}
	}()

	tests := []struct {
		name         string
		proxy        Proxy
		wgPort       int
		endpointAddr *net.UDPAddr
	}{
		{
			name:   "ebpf kernel proxy",
			proxy:  ebpf.NewProxyWrapper(ebpfProxy),
			wgPort: 51831,
		},
		{
			name:   "udp kernel proxy",
			proxy:  udp.NewWGUDPProxy(51832),
			wgPort: 51832,
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			redirectTraffic(t, tt.proxy, tt.wgPort, tt.endpointAddr)
		})
	}
}

func redirectTraffic(t *testing.T, proxy Proxy, wgPort int, endPointAddr *net.UDPAddr) {
	t.Helper()

	msgHelloFromRelay := []byte("hello from relay")
	msgRedirected := [][]byte{
		[]byte("hello 1. to p2p"),
		[]byte("hello 2. to p2p"),
		[]byte("hello 3. to p2p"),
	}

	dummyWgListener, err := net.ListenUDP("udp", &net.UDPAddr{
		IP:   net.IPv4(127, 0, 0, 1),
		Port: wgPort})
	if err != nil {
		t.Fatalf("failed to listen on udp port: %s", err)
	}

	relayedServer, _ := net.ListenUDP("udp",
		&net.UDPAddr{
			IP:   net.IPv4(127, 0, 0, 1),
			Port: 1234,
		},
	)

	relayedConn, _ := net.Dial("udp", "127.0.0.1:1234")

	defer func() {
		_ = dummyWgListener.Close()
		_ = relayedConn.Close()
		_ = relayedServer.Close()
	}()

	if err := proxy.AddTurnConn(context.Background(), endPointAddr, relayedConn); err != nil {
		t.Errorf("error: %v", err)
	}
	defer func() {
		if err := proxy.CloseConn(); err != nil {
			t.Errorf("error: %v", err)
		}
	}()

	proxy.Work()

	if _, err := relayedServer.WriteTo(msgHelloFromRelay, relayedConn.LocalAddr()); err != nil {
		t.Errorf("error relayedServer.Write(msgHelloFromRelay): %v", err)
	}

	n, err := dummyWgListener.Read(make([]byte, 1024))
	if err != nil {
		t.Errorf("error: %v", err)
	}

	if n != len(msgHelloFromRelay) {
		t.Errorf("expected %d bytes, got %d", len(msgHelloFromRelay), n)
	}

	p2pEndpointAddr := &net.UDPAddr{
		IP:   net.IPv4(192, 168, 0, 56),
		Port: 1234,
	}
	proxy.RedirectAs(p2pEndpointAddr)

	for _, msg := range msgRedirected {
		if _, err := relayedServer.WriteTo(msg, relayedConn.LocalAddr()); err != nil {
			t.Errorf("error: %v", err)
		}
	}

	for i := 0; i < len(msgRedirected); i++ {
		buf := make([]byte, 1024)
		n, rAddr, err := dummyWgListener.ReadFrom(buf)
		if err != nil {
			t.Errorf("error: %v", err)
		}

		if rAddr.String() != p2pEndpointAddr.String() {
			t.Errorf("expected %s, got %s", p2pEndpointAddr.String(), rAddr.String())
		}
		if string(buf[:n]) != string(msgRedirected[i]) {
			t.Errorf("expected %s, got %s", string(msgRedirected[i]), string(buf[:n]))
		}
	}
}

func TestProxyCloseByRemoteConn(t *testing.T) {
	ctx := context.Background()

	ebpfProxy := ebpf.NewWGEBPFProxy(51831)
	if err := ebpfProxy.Listen(); err != nil {
		t.Fatalf("failed to initialize ebpf proxy: %s", err)
	}

	defer func() {
		if err := ebpfProxy.Free(); err != nil {
			t.Errorf("failed to free ebpf proxy: %s", err)
		}
	}()

	iceBind := bind.NewICEBind(nil, nil)
	endpointAddress := &net.UDPAddr{
		IP:   net.IPv4(10, 0, 0, 1),
		Port: 1234,
	}
	tests := []struct {
		name            string
		proxy           Proxy
		endpointAddress *net.UDPAddr
	}{
		{
			name:  "ebpf proxy",
			proxy: ebpf.NewProxyWrapper(ebpfProxy),
		},
		{
			name:  "udp proxy",
			proxy: udp.NewWGUDPProxy(51832),
		},
		{
			name:            "bind proxy",
			proxy:           bindproxy.NewProxyBind(iceBind),
			endpointAddress: endpointAddress,
		},
	}

	relayedConn, _ := net.Dial("udp", "127.0.0.1:1234")
	defer func() {
		_ = relayedConn.Close()
	}()
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := tt.proxy.AddTurnConn(ctx, endpointAddress, relayedConn)
			if err != nil {
				t.Errorf("error: %v", err)
			}

			_ = relayedConn.Close()
			if err := tt.proxy.CloseConn(); err != nil {
				t.Errorf("error: %v", err)
			}
		})
	}
}