/**
 * Copyright (C) 2015-2018 Virgil Security Inc.
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     (1) Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *     (2) Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in
 *     the documentation and/or other materials provided with the
 *     distribution.
 *
 *     (3) Neither the name of the copyright holder nor the names of its
 *     contributors may be used to endorse or promote products derived from
 *     this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ''AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * Lead Maintainer: Virgil Security Inc. <support@virgilsecurity.com>
 */

#include <virgil/crypto/VirgilStreamSigner.h>

using virgil::crypto::VirgilByteArray;
using virgil::crypto::VirgilDataSource;
using virgil::crypto::VirgilStreamSigner;

using virgil::crypto::foundation::VirgilHash;

VirgilByteArray VirgilStreamSigner::sign(
        VirgilDataSource& source, const VirgilByteArray& privateKey,
        const VirgilByteArray& privateKeyPassword) {

    // Calculate data digest
    VirgilHash hash(getHashAlgorithm());
    hash.start();
    while (source.hasData()) {
        hash.update(source.read());
    }
    const auto digest = hash.finish();

    // Sign digest
    const auto signature = signHash(digest, privateKey, privateKeyPassword);

    // Pack signature
    return packSignature(signature);
}

bool VirgilStreamSigner::verify(
        VirgilDataSource& source, const VirgilByteArray& sign, const VirgilByteArray& publicKey) {

    // Unpack signature
    const auto signature = unpackSignature(sign); // MUST be before getHashAlgorithm()

    // Calculate data digest
    VirgilHash hash(getHashAlgorithm());
    hash.start();
    while (source.hasData()) {
        hash.update(source.read());
    }
    const auto digest = hash.finish();

    // Verify signature
    return verifyHash(digest, signature, publicKey);
}