package host

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

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

type activationOrderStore struct {
	rootstate.Store
	floor string
	locks int
}

func (s *activationOrderStore) Lock(ctx context.Context, name string) (func(), error) {
	if name == "transaction.lock" {
		if _, err := os.Stat(s.floor); !os.IsNotExist(err) {
			return nil, os.ErrPermission
		}
		s.locks++
	}
	return s.Store.Lock(ctx, name)
}

func TestPlan14ActivationParticipationBeforeFloor(t *testing.T) {
	l := updateParticipationFixture(t)
	x := &release.ReleaseExclusion{Open: func() (rootstate.Store, error) { return &plan14ReleaseStore{}, nil }}
	l.ExcludeLaunches = x.With
	l.VerifyLaunches = func(ctx context.Context, _ uint64) error { return x.Check(ctx) }
	a := &systemApplier{participation: l, optDir: t.TempDir(), dataDir: t.TempDir()}
	s := &activationOrderStore{Store: l.State, floor: filepath.Join(a.dataDir, ".moves", "floor.lock")}
	l.State = s
	if err := x.With(t.Context(), func(ctx context.Context) error { return l.BeginUpdate(ctx, "update") }); err != nil {
		t.Fatal(err)
	}
	s.locks = 0
	if err := a.activationGuard(t.Context(), "new", "old", func(ctx context.Context) error {
		if s.locks != 1 {
			t.Fatalf("participation must be held before floor: %d acquisitions", s.locks)
		}
		return a.clearUpdateBegun(ctx)
	}); err != nil {
		t.Fatal(err)
	}
	if s.locks != 1 {
		t.Fatalf("nested close reacquired participation: %d", s.locks)
	}
}

func TestPlan14SystemApplyOuterReleaseContext(t *testing.T) {
	f := newApplyFixture(t, "stable", "old")
	l := updateParticipationFixture(t)
	lock := &plan14ReleaseStore{}
	x := &release.ReleaseExclusion{Open: func() (rootstate.Store, error) { return lock, nil }}
	l.ExcludeLaunches = x.With
	verified := 0
	l.VerifyLaunches = func(ctx context.Context, _ uint64) error {
		verified++
		return x.Check(ctx)
	}
	if err := x.With(t.Context(), func(ctx context.Context) error { return l.BeginUpdate(ctx, "update") }); err != nil {
		t.Fatal(err)
	}
	verified = 0
	f.a.participation = l
	f.a.floorHook = func(*systemApplier) error {
		if !lock.held {
			return os.ErrPermission
		}
		return nil
	}
	if err := f.a.runWithRelease(t.Context(), true); err != nil {
		t.Fatal(err)
	}
	if verified == 0 {
		t.Fatal("outer release did not reach recovery verifier")
	}
}

func TestPlan14SystemApplyNoCensusReleaseUnchanged(t *testing.T) {
	f := newApplyFixture(t, "stable", "old")
	l := updateParticipationFixture(t)
	if err := l.State.Remove("census.json"); err != nil {
		t.Fatal(err)
	}
	l.ExcludeLaunches = func(context.Context, func(context.Context) error) error {
		t.Fatal("no-census apply took release exclusion")
		return nil
	}
	l.VerifyLaunches = func(context.Context, uint64) error { t.Fatal("no-census apply read root participation"); return nil }
	f.a.participation = l
	if err := f.a.runWithRelease(t.Context(), true); err != nil {
		t.Fatal(err)
	}
}