//go:build linux

package host

import (
	"context"
	"os"
	"path/filepath"
	"strings"
	"testing"

	"github.com/carlosframework/platform/internal/hostbox"
	"github.com/carlosframework/platform/internal/hostguard"
)

type seedAbsentJournal struct {
	rebootJournalFixture
	raw   hostbox.LaunchInventory
	after func()
}

func (j *seedAbsentJournal) Read(context.Context, hostguard.FenceTarget) (hostbox.LaunchInventory, error) {
	return j.raw, nil
}
func (j *seedAbsentJournal) SettleRecovered(context.Context, hostguard.FenceTarget) error {
	j.j.Settled = true
	if j.after != nil {
		j.after()
	}
	return nil
}

func TestFilesSeedKilledUnlaunchedRecovery(t *testing.T) {
	for _, fault := range []string{"none", "live-controller", "reused-parent", "reappears", "role", "boot-change", "descriptor", "foreign-parent", "no-journal"} {
		t.Run(fault, func(t *testing.T) {
			root, proc := t.TempDir(), t.TempDir()
			os.MkdirAll(filepath.Join(proc, "sys/kernel/random"), 0700)
			os.WriteFile(filepath.Join(proc, "sys/kernel/random/boot_id"), []byte("boot\n"), 0600)
			target := hostguard.FenceTarget{Host: "seed.example", Incarnation: "inc", Stamp: 11, Session: 13, Box: "box", Enrollment: "enroll", BootID: "boot", ControllerID: "controller", FenceID: "fence"}
			agent := "/sys/fs/cgroup/system.slice/carlos-edge.service"
			parent, err := claimContainmentParent(agent, target)
			if err != nil {
				t.Fatal(err)
			}
			group := hostbox.StopCgroupIdentity{RelativePath: parent, Device: 1, Inode: 2}
			j := &seedAbsentJournal{rebootJournalFixture: rebootJournalFixture{j: hostbox.StopKernelJournal{V: 1, Target: target, ControllerPID: 42, ProcessStart: "123", Cgroups: []hostbox.StopCgroupIdentity{group}}}, raw: hostbox.LaunchInventory{Target: target, Groups: []hostbox.LaunchGroup{{RelativePath: parent, Device: 1, Inode: 2}}, NoState: true}}
			state := t.TempDir()
			k := LinuxStopKernel{AgentCgroup: func(context.Context) (string, error) { return agent, nil }, Journal: j, CgroupRoot: root, ProcRoot: proc, ManagedRoots: map[string]string{"data": state}}
			switch fault {
			case "live-controller":
				os.MkdirAll(filepath.Join(proc, "42"), 0700)
				os.WriteFile(filepath.Join(proc, "42/stat"), []byte("42 (fixture) S "+strings.Repeat("0 ", 18)+"123 0"), 0600)
			case "reused-parent":
				os.MkdirAll(filepath.Join(root, parent), 0700)
			case "reappears":
				j.after = func() { os.MkdirAll(filepath.Join(root, parent), 0700) }
			case "role":
				j.j.UnitReservationIDs = []string{"main"}
			case "boot-change":
				os.WriteFile(filepath.Join(proc, "sys/kernel/random/boot_id"), []byte("other"), 0600)
			case "descriptor":
				os.MkdirAll(filepath.Join(proc, "42/fd"), 0700)
				os.WriteFile(filepath.Join(proc, "42/stat"), []byte("42 (fixture) S "+strings.Repeat("0 ", 18)+"456 0"), 0600)
				os.Symlink(filepath.Join(state, "data.db")+" (deleted)", filepath.Join(proc, "42/fd/3"))
			case "foreign-parent":
				j.j.Cgroups[0].RelativePath = "other/group"
			case "no-journal":
				k.Journal = &j.rebootJournalFixture
			}
			in := StopInventory{Complete: true, Entries: []hostbox.StopInventoryEntry{{Kind: "path", ManagedRoot: "data", RelativePath: "data.db"}}}
			evidence, _, err := k.recoverUnlaunchedAbsent(t.Context(), target, in, j.j, j)
			if fault == "none" {
				if err != nil || !j.j.Settled || evidence.ObservedBootID != "boot" {
					t.Fatal(err, evidence)
				}
				return
			}
			if err == nil {
				t.Fatal("unsafe recovery accepted", fault)
			}
			if fault != "reappears" && j.j.Settled {
				t.Fatal("refusal settled journal")
			}
		})
	}
}