package host

import (
	"context"
	"errors"
	"github.com/carlosframework/platform/internal/hostbox"
	"github.com/carlosframework/platform/internal/hostguard"
	"os"
)

// A row mutation can commit before the inventory journal. Settle that exact
// root intention locally even if the claim has since advanced. This grants no
// new timer write: SQL is checked only against the effect root already intended.
func (h ClaimRootHTTP) settleTimerInventory(ctx context.Context, q hostbox.JournalRequest, raw []byte) (bool, error) {
	if q.Timer == nil {
		return false, nil
	}
	if h.Reconcile.Registry == nil || h.Journals == nil {
		return false, hostbox.ErrUnsupported
	}
	m := q.Timer
	applied := func() (bool, error) {
		row, err := h.Reconcile.Registry.GetTimer(m.Timer.Host, m.Timer.Name)
		if errors.Is(err, os.ErrNotExist) {
			return m.Remove, nil
		}
		if err != nil {
			return false, err
		}
		return !m.Remove && row != nil && *row == m.Timer, nil
	}
	done, err := applied()
	if err != nil || !done {
		return false, err
	}
	err = h.Stop.Coordinator.Guard.SettleRootInventory(ctx, q.Target.Host, raw, func(in hostguard.RootInstallation) error {
		if in.Host != q.Inventory.Host || in.Incarnation != q.Inventory.Incarnation || in.Stamp != q.Inventory.InstallationStamp || in.InventoryRevision != q.Revision+1 {
			return hostbox.ErrChanged
		}
		exact, err := applied()
		if err != nil {
			return err
		}
		if !exact {
			return hostbox.ErrChanged
		}
		_, err = h.Journals.CompletePendingInventory(ctx, in.Box+"/"+in.Enrollment, q)
		return err
	})
	return err == nil, err
}