// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2014 The Bitcoin Core developers
// Copyright (c) 2019      The Hush developers
// Distributed under the GPLv3 software license, see the accompanying
// file COPYING or https://www.gnu.org/licenses/gpl-3.0.en.html

/******************************************************************************
 * Copyright © 2014-2019 The SuperNET Developers.                             *
 *                                                                            *
 * See the AUTHORS, DEVELOPER-AGREEMENT and LICENSE files at                  *
 * the top-level directory of this distribution for the individual copyright  *
 * holder information and the developer policies on copyright and licensing.  *
 *                                                                            *
 * Unless otherwise agreed in a custom licensing agreement, no part of the    *
 * SuperNET software, including this file may be copied, modified, propagated *
 * or distributed except according to the terms contained in the LICENSE file *
 *                                                                            *
 * Removal or modification of this copyright notice is prohibited.            *
 *                                                                            *
 ******************************************************************************/

#include "random.h"

#include "support/cleanse.h"
#ifdef _WIN32
#include "compat.h" // for Windows API
#endif
#include "serialize.h"        // for begin_ptr(vec)
#include "util.h"             // for LogPrint()
#include "utilstrencodings.h" // for GetTime()

#include <limits>

#ifndef _WIN32
#include <sys/time.h>
#endif

#include "sodium.h"

static inline int64_t GetPerformanceCounter()
{
    int64_t nCounter = 0;
#ifdef _WIN32
    QueryPerformanceCounter((LARGE_INTEGER*)&nCounter);
#else
    timeval t;
    gettimeofday(&t, NULL);
    nCounter = (int64_t)(t.tv_sec * 1000000 + t.tv_usec);
#endif
    return nCounter;
}

void GetRandBytes(unsigned char* buf, size_t num)
{
    randombytes_buf(buf, num);
}

uint64_t GetRand(uint64_t nMax)
{
    if (nMax == 0)
        return 0;

    // The range of the random source must be a multiple of the modulus
    // to give every possible output value an equal possibility
    uint64_t nRange = (std::numeric_limits<uint64_t>::max() / nMax) * nMax;
    uint64_t nRand = 0;
    do {
        GetRandBytes((unsigned char*)&nRand, sizeof(nRand));
    } while (nRand >= nRange);
    return (nRand % nMax);
}

int GetRandInt(int nMax)
{
    return GetRand(nMax);
}

uint256 GetRandHash()
{
    uint256 hash;
    GetRandBytes((unsigned char*)&hash, sizeof(hash));
    return hash;
}

uint32_t insecure_rand_Rz = 11;
uint32_t insecure_rand_Rw = 11;
void seed_insecure_rand(bool fDeterministic)
{
    // The seed values have some unlikely fixed points which we avoid.
    if (fDeterministic) {
        insecure_rand_Rz = insecure_rand_Rw = 11;
    } else {
        uint32_t tmp;
        do {
            GetRandBytes((unsigned char*)&tmp, 4);
        } while (tmp == 0 || tmp == 0x9068ffffU);
        insecure_rand_Rz = tmp;
        do {
            GetRandBytes((unsigned char*)&tmp, 4);
        } while (tmp == 0 || tmp == 0x464fffffU);
        insecure_rand_Rw = tmp;
    }
}

int GenIdentity(int n)
{
    return n-1;
}