//go:build linux

package instancectl

import (
	"context"
	"fmt"
	"net"
	"os"
	"path/filepath"
	"testing"
	"time"
)

func TestPlan14ExecPeerNamespaceTransition(t *testing.T) {
	for _, attack := range []string{"none", "invocation", "group", "peer", "state"} {
		t.Run(attack, func(t *testing.T) {
			dir, err := os.MkdirTemp("", "ep")
			if err != nil {
				t.Fatal(err)
			}
			defer os.RemoveAll(dir)
			ln, err := net.Listen("unix", filepath.Join(dir, "s"))
			if err != nil {
				t.Fatal(err)
			}
			defer ln.Close()
			client, err := net.Dial("unix", filepath.Join(dir, "s"))
			if err != nil {
				t.Fatal(err)
			}
			defer client.Close()
			server, err := ln.Accept()
			if err != nil {
				t.Fatal(err)
			}
			defer server.Close()
			s := ClaimUnitStarted{Unit: "console.service", InvocationID: "inv", ControlGroup: "group", MainPID: os.Getpid() + 10000}
			calls := 0
			u := ClaimUnits{Poll: time.Millisecond, Systemctl: func(context.Context, ...string) (string, error) {
				calls++
				pid, inv, group, state := os.Getpid(), "inv", "/group", "active"
				if calls == 1 || attack == "peer" {
					pid += 10000
				}
				switch attack {
				case "invocation":
					inv = "replacement"
				case "group":
					group = "/sibling"
				case "state":
					state = "failed"
				}
				return fmt.Sprintf("MainPID=%d\nInvocationID=%s\nControlGroup=%s\nActiveState=%s\n", pid, inv, group, state), nil
			}}
			ctx, cancel := context.WithTimeout(t.Context(), 50*time.Millisecond)
			defer cancel()
			err = u.pinExecPeer(ctx, server, &s)
			if attack == "none" {
				if err != nil || s.MainPID != os.Getpid() || calls < 2 {
					t.Fatal(s, calls, err)
				}
			} else if err == nil {
				t.Fatal("accepted changed identity", attack)
			}
		})
	}
}