//go:build linux

package host

import (
	"context"
	"github.com/carlosframework/platform/internal/cgroup"
	"github.com/carlosframework/platform/internal/hostbox"
	"os"
	"path/filepath"
	"testing"
)

type fix1HostLaunches struct {
	records []hostbox.LaunchInventory
}

func (f fix1HostLaunches) HostLaunches(context.Context, string) ([]hostbox.LaunchInventory, error) {
	return f.records, nil
}

func TestPlan11Fix1NoProcessHistoricalInstallations(t *testing.T) {
	for _, shape := range []string{"old-incarnation", "old-stamp", "current"} {
		t.Run(shape, func(t *testing.T) {
			fx := newWritersKernelFixture(t)
			fx.dropAgentHolds(t)
			old := fx.target
			switch shape {
			case "old-incarnation":
				old.Incarnation = "old"
			case "old-stamp":
				old.Stamp--
			}
			records := fix1HostLaunches{records: []hostbox.LaunchInventory{{Target: old}}}
			target := fx.target
			target.Session = 0
			_, err := verifyNoProcessAt(t.Context(), fx.roots(), records, target, fx.inv)
			if shape == "current" {
				if err == nil {
					t.Fatal("current installation journal accepted")
				}
				return
			}
			if err != nil {
				t.Fatalf("old installation blocks witness: %v", err)
			}
		})
	}
}

func TestPlan11Fix1NoProcessWalksClaimChildren(t *testing.T) {
	for _, populated := range []string{"0", "1"} {
		t.Run(populated, func(t *testing.T) {
			fx := newWritersKernelFixture(t)
			fx.dropAgentHolds(t)
			old := fx.target
			old.Stamp--
			name := cgroup.ExecName(claimContainmentName(old))
			dir := filepath.Join(fx.agentCgroup, name)
			child := filepath.Join(dir, "role-child")
			if err := os.MkdirAll(child, 0700); err != nil {
				t.Fatal(err)
			}
			for path, value := range map[string]string{dir: "0", child: populated} {
				if err := os.WriteFile(filepath.Join(path, "cgroup.events"), []byte("populated "+value+"\n"), 0600); err != nil {
					t.Fatal(err)
				}
			}
			records := fix1HostLaunches{records: []hostbox.LaunchInventory{{Target: old}}}
			target := fx.target
			target.Session = 0
			ev, err := verifyNoProcessAt(t.Context(), fx.roots(), records, target, fx.inv)
			if populated == "1" {
				if err == nil {
					t.Fatal("populated claim child missed")
				}
				return
			}
			if err != nil || len(ev.CgroupIdentities) != 3 {
				t.Fatalf("claim group not witnessed: %+v %v", ev, err)
			}
		})
	}
}

func TestPlan11Fix1NoProcessReadsRootJournal(t *testing.T) {
	f := newLaunchFixture(t, servingOp())
	fx := newWritersKernelFixture(t)
	fx.dropAgentHolds(t)
	target := fx.target
	target.Session = 0
	target.Stamp++
	if _, err := verifyNoProcessAt(t.Context(), fx.roots(), f.journal, target, fx.inv); err != nil {
		t.Fatalf("historical persisted launch blocks new installation: %v", err)
	}
	target.Stamp--
	if _, err := verifyNoProcessAt(t.Context(), fx.roots(), f.journal, target, fx.inv); err == nil {
		t.Fatal("persisted current installation accepted")
	}
}