// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2020 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#ifndef BITCOIN_UTIL_MESSAGE_H
#define BITCOIN_UTIL_MESSAGE_H

#include <string>

extern const std::string strMessageMagic;

/** The result of a signed message verification.
 * Message verification takes as an input:
 * - address (with whose private key the message is supposed to have been signed)
 * - signature
 * - message
 */
enum class MessageVerificationResult {
    //! The provided address is invalid.
    ERR_INVALID_ADDRESS,

    //! The provided address is valid but does not refer to a public key.
    ERR_ADDRESS_NO_KEY,

    //! The provided signature couldn't be parsed (maybe invalid base64).
    ERR_MALFORMED_SIGNATURE,

    //! A public key could not be recovered from the provided signature and message.
    ERR_PUBKEY_NOT_RECOVERED,

    //! The message was not signed with the private key of the provided address.
    ERR_NOT_SIGNED,

    //! The message verification was successful.
    OK
};

/** Verify a signed message.
 * @param[in] address Signer's bitcoin address, it must refer to a public key.
 * @param[in] signature The signature in base64 format.
 * @param[in] message The message that was signed.
 * @return result code */
MessageVerificationResult MessageVerify(
    const std::string& address,
    const std::string& signature,
    const std::string& message);

#endif // BITCOIN_UTIL_MESSAGE_H