//go:build linux

package host

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"os"
	"testing"

	"github.com/carlosframework/platform/internal/hostclaim"
	"github.com/carlosframework/platform/internal/hostguard"
	"github.com/carlosframework/platform/internal/registry"
	"github.com/carlosframework/platform/internal/release"
)

type plan9D4RetagConflict struct {
	release.Store
	armed, failed bool
}

func (s *plan9D4RetagConflict) Put(ctx context.Context, key string, body []byte, etag string) (string, error) {
	var c hostclaim.Claim
	if s.armed && json.Unmarshal(body, &c) == nil && c.Holder != nil && c.Inventory["box-1"].Paths[recoveryHost+".db.gen"] == c.Holder.Stamp {
		s.armed = false
		s.failed = true
		return "", release.ErrCASConflict
	}
	return s.Store.Put(ctx, key, body, etag)
}

func TestPlan9D4RetirementCASFailureReplaysWithoutMarker(t *testing.T) {
	d := plan9D4Landing(t)
	st := &plan9D4RetagConflict{Store: d.f.claims}
	d.f.claims = st
	d.f.guard.Claims = hostguard.StoreReader{Store: st}
	c := d.controller("boot-1", "controller-1", 4101, "start-1", true)
	first := d.mustStart(t, c, plan9D4Probe, false)
	st.armed = true
	second, err := d.start(t, c, plan9D4Probe, true)
	if !errors.Is(err, release.ErrCASConflict) || !st.failed {
		t.Fatalf("retag CAS was not interrupted: %v", err)
	}
	if _, err := os.Stat(d.db + ".gen"); !errors.Is(err, os.ErrNotExist) {
		t.Fatalf("marker still present after park: %v", err)
	}
	if got := d.f.read().Claim.Inventory["box-1"].Paths[recoveryHost+".db.gen"]; got != first.Claim.Holder.Stamp {
		t.Fatalf("tag changed on failed CAS: %d", got)
	}
	// Replay the same admitted start. Its absent marker must not bypass the
	// unfinished retirement or permit bytes under the predecessor's tag.
	start, err := c.runtime.Prepare(t.Context(), registry.Route{Host: recoveryHost}, second, plan9D4Probe)
	if err != nil {
		t.Fatal(err)
	}
	if err := start.Restore(t.Context()); err != nil {
		t.Fatal(err)
	}
	if err := os.WriteFile(d.db, []byte(fmt.Sprintf("written by session %d", second.Claim.Holder.Session)), 0600); err != nil {
		t.Fatal(err)
	}
	d.requireRetired(t, first, second, false)
	third := d.mustStart(t, c, plan9D4Probe, true)
	d.requireRetired(t, second, third, false)
}

func TestPlan9D4RetirementCollectorKeepsItsSelectedChore(t *testing.T) {
	d := plan9D4Landing(t)
	c := d.controller("boot-1", "controller-1", 4101, "start-1", true)
	d.mustStart(t, c, plan9D4Probe, false)
	d.step(t, "retirement chore", hostclaim.QueueLocalPark("m1", "box-1", func() string { return "retire-this-installation" }))
	h := d.f.read().Claim.Holder
	row := registry.Route{Host: recoveryHost, ClaimOwnership: registry.ClaimOwnership{ClaimIncarnation: h.Incarnation, ClaimStamp: h.Stamp}}
	target, err := c.assembly.collectRetirementStop(t.Context(), row)
	if err != nil {
		t.Fatal(err)
	}
	if target.ObligationID != "retire-this-installation" || len(d.f.requests) != 1 || d.f.requests[0].ObligationID != target.ObligationID {
		t.Fatalf("retirement relabelled as a wake stop: %+v", target)
	}
}