//go:build linux

package host

import (
	"errors"
	"fmt"
	"log"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"testing"

	"github.com/carlosframework/platform/internal/rootstate"
)

func TestRunAdoptDisabledClaimsArmsSystemUnitsBeforeRegistryOpenFailure(t *testing.T) {
	if os.Getenv("CARLOS_TEST_ADOPT_ORDER_HELPER") == "1" {
		os.Unsetenv("CARLOS_HOST_CLAIM")
		probe := func(args ...string) (string, error) {
			switch args[0] {
			case "is-active":
				return "inactive\n", errors.New("exit status 3")
			case "is-enabled":
				return "disabled\n", errors.New("exit status 1")
			}
			return "", nil
		}
		systemctl := func(args ...string) (string, error) {
			f, err := os.OpenFile(os.Getenv("CARLOS_TEST_ADOPT_SYSTEMCTL_CALLS"), os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0o600)
			if err != nil {
				return "", err
			}
			defer f.Close()
			_, err = fmt.Fprintln(f, strings.Join(args, " "))
			return "", err
		}
		ensure := func() {
			ensureSystemUnits(
				os.Getenv("CARLOS_TEST_ADOPT_ETC"),
				os.Getenv("CARLOS_TEST_ADOPT_SYSTEM_LOCK"),
				systemctl,
				probe,
				log.Printf,
			)
		}
		runAdoptWithEnsureSystemUnits([]string{"-registry", os.Getenv("CARLOS_TEST_ADOPT_REGISTRY")}, nil, ensure,
			noCensusAdoptSource(func() (rootstate.Store, error) { return &plan14ReleaseStore{}, nil }))
		return
	}

	root := t.TempDir()
	if err := os.MkdirAll(filepath.Join(root, "data"), 0o755); err != nil {
		t.Fatal(err)
	}
	blocker := filepath.Join(root, "not-a-directory")
	if err := os.WriteFile(blocker, []byte("block registry parent"), 0o600); err != nil {
		t.Fatal(err)
	}
	registryPath := filepath.Join(blocker, "registry.db")
	etc := filepath.Join(root, "etc")
	callsPath := filepath.Join(root, "systemctl.calls")
	cmd := exec.Command(os.Args[0], "-test.run=^TestRunAdoptDisabledClaimsArmsSystemUnitsBeforeRegistryOpenFailure$", "-test.v")
	cmd.Dir = root
	cmd.Env = isolatedAdoptOrderEnv(t,
		"CARLOS_HOST_CLAIM=",
		"CARLOS_DATA_DIR="+filepath.Join(root, "data"),
		"CARLOS_OPT_DIR="+filepath.Join(root, "opt"),
		"CARLOS_TEST_ADOPT_ORDER_HELPER=1",
		"CARLOS_TEST_ADOPT_REGISTRY="+registryPath,
		"CARLOS_TEST_ADOPT_ETC="+etc,
		"CARLOS_TEST_ADOPT_SYSTEM_LOCK="+filepath.Join(root, "system.lock"),
		"CARLOS_TEST_ADOPT_SYSTEMCTL_CALLS="+callsPath,
	)
	out, err := cmd.CombinedOutput()
	if err == nil {
		t.Fatalf("helper succeeded; want fatal registry-open failure:\n%s", out)
	}
	got := string(out)
	unitErr := "adopt: self-update units installed and armed"
	registryErr := "adopt: open registry " + registryPath + ":"
	unitAt, registryAt := strings.Index(got, unitErr), strings.Index(got, registryErr)
	if unitAt < 0 {
		t.Fatalf("unit arming was not reported before exit:\n%s", got)
	}
	if registryAt < 0 {
		t.Fatalf("registry error does not match the adopt error contract:\n%s", got)
	}
	if unitAt > registryAt {
		t.Fatalf("registry failed before unit repair ran:\n%s", got)
	}
	for _, unit := range systemUnitFiles {
		if _, err := os.Stat(filepath.Join(etc, "systemd", "system", unit)); err != nil {
			t.Errorf("unit repair did not install %s before registry failure: %v", unit, err)
		}
	}
	calls, err := os.ReadFile(callsPath)
	if err != nil {
		t.Fatalf("read systemctl calls: %v", err)
	}
	called := string(calls)
	for _, want := range []string{
		"daemon-reload",
		"enable carlos-system-update.path carlos-system-recover.service carlos-instance-control.socket",
		"start carlos-system-update.path carlos-instance-control.socket",
	} {
		if !strings.Contains(called, want) {
			t.Errorf("systemctl calls lack %q:\n%s", want, called)
		}
	}
}

func isolatedAdoptOrderEnv(t *testing.T, extra ...string) []string {
	t.Helper()
	home := t.TempDir()
	drop := map[string]bool{
		"CARLOS_SERVICE_TOKEN": true,
		"CARLOS_CREDENTIALS":   true,
		"CARLOS_CONSOLE":       true,
		"CARLOS_DESTINATION":   true,
		"HOME":                 true,
	}
	for _, kv := range extra {
		if key, _, ok := strings.Cut(kv, "="); ok {
			drop[key] = true
		}
	}
	var env []string
	for _, kv := range os.Environ() {
		key, _, _ := strings.Cut(kv, "=")
		if !drop[key] {
			env = append(env, kv)
		}
	}
	env = append(env,
		"CARLOS_CREDENTIALS="+filepath.Join(home, "credentials"),
		"CARLOS_CONSOLE=",
		"CARLOS_DESTINATION=",
		"HOME="+home,
	)
	return append(env, extra...)
}