package innerring import ( "fmt" "sync" "time" "github.com/nspcc-dev/neo-go/pkg/crypto/keys" ) type ( irFetcher interface { InnerRingKeys() (keys.PublicKeys, error) } committeeFetcher interface { Committee() (keys.PublicKeys, error) } innerRingIndexer struct { sync.RWMutex irFetcher irFetcher commFetcher committeeFetcher key *keys.PublicKey timeout time.Duration ind indexes lastAccess time.Time } indexes struct { innerRingIndex, innerRingSize int32 alphabetIndex int32 } ) func newInnerRingIndexer(comf committeeFetcher, irf irFetcher, key *keys.PublicKey, to time.Duration) *innerRingIndexer { return &innerRingIndexer{ irFetcher: irf, commFetcher: comf, key: key, timeout: to, } } func (s *innerRingIndexer) update() (ind indexes, err error) { s.RLock() if time.Since(s.lastAccess) < s.timeout { s.RUnlock() return s.ind, nil } s.RUnlock() s.Lock() defer s.Unlock() if time.Since(s.lastAccess) < s.timeout { return s.ind, nil } innerRing, err := s.irFetcher.InnerRingKeys() if err != nil { return indexes{}, err } s.ind.innerRingIndex = keyPosition(s.key, innerRing) s.ind.innerRingSize = int32(len(innerRing)) alphabet, err := s.commFetcher.Committee() if err != nil { return indexes{}, err } s.ind.alphabetIndex = keyPosition(s.key, alphabet) s.lastAccess = time.Now() return s.ind, nil } func (s *innerRingIndexer) InnerRingIndex() (int32, error) { ind, err := s.update() if err != nil { return 0, fmt.Errorf("can't update index state: %w", err) } return ind.innerRingIndex, nil } func (s *innerRingIndexer) InnerRingSize() (int32, error) { ind, err := s.update() if err != nil { return 0, fmt.Errorf("can't update index state: %w", err) } return ind.innerRingSize, nil } func (s *innerRingIndexer) AlphabetIndex() (int32, error) { ind, err := s.update() if err != nil { return 0, fmt.Errorf("can't update index state: %w", err) } return ind.alphabetIndex, nil } // keyPosition returns "-1" if key is not found in the list, otherwise returns // index of the key. func keyPosition(key *keys.PublicKey, list keys.PublicKeys) (result int32) { result = -1 for i := range list { if key.Equal(list[i]) { result = int32(i) break } } return result }