package host

import (
	"context"
	"crypto/ed25519"
	"crypto/sha256"
	"encoding/hex"
	"path/filepath"
	"reflect"

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

// Retain the independently verified pointer before its artifact can replace a
// recovery binary. A pointer race retries; no existing identity is overwritten.
func rememberRootFloorSystemIdentity(ctx context.Context, store release.Store, pub ed25519.PublicKey, opt string, expected *release.SystemPointer) error {
	raw, _, err := store.Get(ctx, release.SystemPointerKey("router", expected.Channel))
	if err != nil {
		return err
	}
	verified, err := release.VerifySystemIdentity(pub, raw)
	if err != nil {
		return err
	}
	if verified.Component != "router" || verified.Channel != expected.Channel || !reflect.DeepEqual(verified.Current, expected.Current) {
		return errRootFloorHistory
	}
	dir, err := rootstate.Open(filepath.Join(opt, "system", "guard", "identities"), true, true)
	if err != nil {
		return err
	}
	defer dir.Close()
	digest := sha256.Sum256(raw)
	return dir.Write(hex.EncodeToString(digest[:])+".json", raw)
}