podc

type Backend interface {
	// Address returns the owner's address
	Address() common.Address

	// Validators returns the validator set
	Validators(proposal Proposal) ValidatorSet // old istanbul method, I'll remove it in the future after debuging

	// EventMux returns the event mux in backend
	EventMux() *event.TypeMux

	// Send sends a message to specific target : 특정 노드에 보낼때,
	Send(payload []byte, target common.Address) error

	// Broadcast sends a message to all validators : 전체 노드에 보낼때, 기 정의된 Validator집합에..
	Broadcast(valSet ValidatorSet, payload []byte) error

	// Multicast sends a message to specific targets
	Multicast(payload []byte, targets []common.Address) error

	// Commit delivers an approved proposal to backend.
	// The delivered proposal will be put into blockchain.
	Commit(proposal Proposal, seals []byte) error

	// NextRound is called when we want to trigger next Seal()
	NextRound() error

	// Verify verifies the proposal.
	Verify(Proposal) error

	// Sign signs input data with the backend's private key
	Sign([]byte) ([]byte, error)

	// CheckSignature verifies the signature by checking if it's signed by
	// the given validator
	CheckSignature(data []byte, addr common.Address, sig []byte) error
}

type Config struct {
	RequestTimeout uint64         `toml:",omitempty"` // The timeout for each Istanbul round in milliseconds. This timeout should be larger than BlockPauseTime
	BlockPeriod    uint64         `toml:",omitempty"` // Default minimum difference between two consecutive block's timestamps in second
	BlockPauseTime uint64         `toml:",omitempty"` // Delay time if no tx in block, the value should be larger than BlockPeriod
	ProposerPolicy ProposerPolicy `toml:",omitempty"` // The policy for proposer selection
	Epoch          uint64         `toml:",omitempty"` // The number of blocks after which to checkpoint and reset the pending votes
}

type ConsensusDataEvent struct {
	// target to send message
	Target common.Address
	// consensus message data
	Data []byte
}

type D_commit struct {
	View     *View
	Proposal Proposal
}

type D_select struct {
	// TODO: define Coordinator struct like
	View     *View
	Proposal Proposal
}

type FinalCommittedEvent struct {
	Proposal Proposal
	Proposer common.Address
}

type MessageEvent struct {
	Payload []byte
}

type Preprepare struct {
	View     *View
	Proposal Proposal
}

type Proposal interface {
	// Number retrieves the sequence number of this proposal.
	Number() *big.Int

	// Hash retrieves the hash of this proposal.
	Hash() common.Hash

	EncodeRLP(w io.Writer) error

	DecodeRLP(s *rlp.Stream) error

	String() string
}

type ProposalQman interface {
	// Number retrieves the sequence number of this proposal.
	Number() *big.Int

	// Hash retrieves the hash of this proposal.
	Hash() common.Hash

	EncodeRLP(w io.Writer) error

	DecodeRLP(s *rlp.Stream) error

	String() string
}

type ProposalSelector func(ValidatorSet, common.Address, uint64) Validator

type ProposerPolicy uint64

type QmanDataEvent struct {
	// target to send message
	Target common.Address
	// consensus message data
	Data []byte
}

type Request struct {
	Proposal Proposal
}

type RequestEvent struct {
	Proposal Proposal
}

type RequestEventQman struct {
	Proposal Proposal
}

type RequestQman struct {
	Proposal ProposalQman
}

type Subject struct {
	View   *View
	Digest common.Hash
}

type Validator interface {
	// Address returns address
	Address() common.Address

	// String representation of Validator
	String() string

	Tag() common.Tag

	Qrnd() uint64

	SetAddress(a common.Address)

	SetTag(t common.Tag)

	SetQrnd(q uint64)
}

type ValidatorSet interface {
	// Calculate the proposer
	CalcProposer(lastProposer common.Address, round uint64) // 최초 Proposer 가 누군지 계산 ,,

	// Return the validator size
	Size() int
	// Return the validator array
	List() []Validator
	// Get validator by index
	GetByIndex(i uint64) Validator
	// Get validator by given address
	GetByAddress(addr common.Address) (int, Validator)
	// Get current proposer
	GetProposer() Validator

	// Check whether the validator with given address is a proposer
	IsProposer(address common.Address) bool

	// Add validator
	AddValidator(address common.Address) bool
	// Remove validator
	RemoveValidator(address common.Address) bool
	// Copy validator set
	Copy() ValidatorSet
	// Get the maximum number of faulty nodes
	F() int
}

type Validators []Validator // go 배열 표현

type View struct {
	Round    *big.Int
	Sequence *big.Int
}