package host

import (
	"context"
	"github.com/carlosframework/platform/internal/hostguard"
	"github.com/carlosframework/platform/internal/stopevidence"
)

// Preserve root's optional observation contracts when isolated launch wraps
// the stop kernel. Unit absence is checked before and after the inner kernel scan.
func (k claimUnitStopKernel) VerifyWritersStopped(ctx context.Context, t hostguard.FenceTarget, inv StopInventory, peer StopPeer, hints []stopevidence.DescriptorHint) (WritersKernelEvidence, error) {
	inner, ok := k.Inner.(stopWritersKernel)
	if !ok || k.Journal == nil || k.Units == nil {
		return WritersKernelEvidence{}, ErrClaimStopUnavailable
	}
	in, err := k.Journal.Read(ctx, t)
	if err != nil {
		return WritersKernelEvidence{}, err
	}
	if !in.WritersClosed {
		return WritersKernelEvidence{}, ErrClaimStopInventory
	}
	if err := k.Units.Gone(ctx, t.Host, ""); err != nil {
		return WritersKernelEvidence{}, err
	}
	if _, err := k.settleUnits(ctx, t); err != nil {
		return WritersKernelEvidence{}, err
	}
	seen, err := inner.VerifyWritersStopped(ctx, t, inv, peer, hints)
	if err != nil {
		return WritersKernelEvidence{}, err
	}
	if err := k.Units.Gone(ctx, t.Host, ""); err != nil {
		return WritersKernelEvidence{}, err
	}
	return seen, nil
}

func (k claimUnitStopKernel) VerifyNoProcess(ctx context.Context, t hostguard.FenceTarget, inv StopInventory) (StopKernelEvidence, error) {
	inner, ok := k.Inner.(stopNoProcessKernel)
	if !ok || k.Units == nil || t.Session != 0 {
		return StopKernelEvidence{}, ErrClaimStopUnavailable
	}
	if err := k.Units.Gone(ctx, t.Host, ""); err != nil {
		return StopKernelEvidence{}, err
	}
	return inner.VerifyNoProcess(ctx, t, inv)
}