consensus

type Communicator interface {
	Broadcast(msg *pb.Message, peerType pb.PeerEndpoint_Type) error
	Unicast(msg *pb.Message, receiverHandle *pb.PeerID) error
}

type Consenter interface {
	RecvMsg(msg *pb.Message, senderHandle *pb.PeerID) error // Called serially with incoming messages from gRPC
	ExecutionConsumer
}

type ExecutionConsumer interface {
	Executed(tag interface{})                                // Called whenever Execute completes
	Committed(tag interface{}, target *pb.BlockchainInfo)    // Called whenever Commit completes
	RolledBack(tag interface{})                              // Called whenever a Rollback completes
	StateUpdated(tag interface{}, target *pb.BlockchainInfo) // Called when state transfer completes, if target is nil, this indicates a failure and a new target should be supplied
}

type Executor interface {
	Start()                                                                     // Bring up the resources needed to use this interface
	Halt()                                                                      // Tear down the resources needed to use this interface
	Execute(tag interface{}, txs []*pb.Transaction)                             // Executes a set of transactions, this may be called in succession
	Commit(tag interface{}, metadata []byte)                                    // Commits whatever transactions have been executed
	Rollback(tag interface{})                                                   // Rolls back whatever transactions have been executed
	UpdateState(tag interface{}, target *pb.BlockchainInfo, peers []*pb.PeerID) // Attempts to synchronize state to a particular target, implicitly calls rollback if needed
}

type Inquirer interface {
	GetNetworkInfo() (self *pb.PeerEndpoint, network []*pb.PeerEndpoint, err error)
	GetNetworkHandles() (self *pb.PeerID, network []*pb.PeerID, err error)
}

type LedgerManager interface {
	InvalidateState() // Invalidate informs the ledger that it is out of date and should reject queries
	ValidateState()   // Validate informs the ledger that it is back up to date and should resume replying to queries
}

type LegacyExecutor interface {
	BeginTxBatch(id interface{}) error
	ExecTxs(id interface{}, txs []*pb.Transaction) ([]byte, error)
	CommitTxBatch(id interface{}, metadata []byte) (*pb.Block, error)
	RollbackTxBatch(id interface{}) error
	PreviewCommitTxBatch(id interface{}, metadata []byte) ([]byte, error)
}

type NetworkStack interface {
	Communicator
	Inquirer
}

type ReadOnlyLedger interface {
	GetBlock(id uint64) (block *pb.Block, err error)
	GetBlockchainSize() uint64
	GetBlockchainInfo() *pb.BlockchainInfo
	GetBlockchainInfoBlob() []byte
	GetBlockHeadMetadata() ([]byte, error)
}

type SecurityUtils interface {
	Sign(msg []byte) ([]byte, error)
	Verify(peerID *pb.PeerID, signature []byte, message []byte) error
}

type Stack interface {
	NetworkStack
	SecurityUtils
	Executor
	LegacyExecutor
	LedgerManager
	ReadOnlyLedger
	StatePersistor
}

type StatePersistor interface {
	StoreState(key string, value []byte) error
	ReadState(key string) ([]byte, error)
	ReadStateSet(prefix string) (map[string][]byte, error)
	DelState(key string)
}