// Copyright (c) 2022 BitMaelum Authors
//
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// this software and associated documentation files (the "Software"), to deal in
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//
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package pow

import (
	"time"
)

// ProofOfWork is the structure that keeps information about proof-of-work done for incoming messages. It connects
// the proof-of-work with a message ID which can be used for uploading.
type ProofOfWork struct {
	Challenge string    `json:"challenge"`
	Bits      int       `json:"bits"`
	Proof     uint64    `json:"proof"`
	Expires   time.Time `json:"expires"`
	MsgID     string    `json:"msg_id"`
	Valid     bool      `json:"valid"`
}

// Storable interface is the main interface to store and retrieve proof-of-work
type Storable interface {
	// Retrieve retrieves the given challenge from the storage and returns its proof-of-work info
	Retrieve(challenge string) (*ProofOfWork, error)
	// Store stores the given proof of work in the storage
	Store(pow *ProofOfWork) error
	// Remove removes the given challenge from the storage
	Remove(challenge string) error
}
