// Copyright (c) 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.

#include <blockfilter.h>
#include <clientversion.h>
#include <logging.h>
#include <netaddress.h>
#include <netbase.h>
#include <rpc/client.h>
#include <rpc/request.h>
#include <rpc/server.h>
#include <rpc/util.h>
#include <script/descriptor.h>
#include <script/script.h>
#include <serialize.h>
#include <streams.h>
#include <test/fuzz/FuzzedDataProvider.h>
#include <test/fuzz/fuzz.h>
#include <test/fuzz/util.h>
#include <util/error.h>
#include <util/fees.h>
#include <util/settings.h>
#include <util/strencodings.h>
#include <util/string.h>
#include <util/system.h>
#include <util/translation.h>
#include <util/url.h>
#include <version.h>

#include <cstdint>
#include <cstdlib>
#include <string>
#include <vector>

namespace {
bool LegacyParsePrechecks(const std::string& str)
{
    if (str.empty()) // No empty string allowed
        return false;
    if (str.size() >= 1 && (IsSpace(str[0]) || IsSpace(str[str.size() - 1]))) // No padding allowed
        return false;
    if (!ContainsNoNUL(str)) // No embedded NUL characters allowed
        return false;
    return true;
}

bool LegacyParseInt32(const std::string& str, int32_t* out)
{
    if (!LegacyParsePrechecks(str))
        return false;
    char* endp = nullptr;
    errno = 0; // strtol will not set errno if valid
    long int n = strtol(str.c_str(), &endp, 10);
    if (out) *out = (int32_t)n;
    // Note that strtol returns a *long int*, so even if strtol doesn't report an over/underflow
    // we still have to check that the returned value is within the range of an *int32_t*. On 64-bit
    // platforms the size of these types may be different.
    return endp && *endp == 0 && !errno &&
           n >= std::numeric_limits<int32_t>::min() &&
           n <= std::numeric_limits<int32_t>::max();
}

bool LegacyParseInt64(const std::string& str, int64_t* out)
{
    if (!LegacyParsePrechecks(str))
        return false;
    char* endp = nullptr;
    errno = 0; // strtoll will not set errno if valid
    long long int n = strtoll(str.c_str(), &endp, 10);
    if (out) *out = (int64_t)n;
    // Note that strtoll returns a *long long int*, so even if strtol doesn't report an over/underflow
    // we still have to check that the returned value is within the range of an *int64_t*.
    return endp && *endp == 0 && !errno &&
           n >= std::numeric_limits<int64_t>::min() &&
           n <= std::numeric_limits<int64_t>::max();
}

bool LegacyParseUInt32(const std::string& str, uint32_t* out)
{
    if (!LegacyParsePrechecks(str))
        return false;
    if (str.size() >= 1 && str[0] == '-') // Reject negative values, unfortunately strtoul accepts these by default if they fit in the range
        return false;
    char* endp = nullptr;
    errno = 0; // strtoul will not set errno if valid
    unsigned long int n = strtoul(str.c_str(), &endp, 10);
    if (out) *out = (uint32_t)n;
    // Note that strtoul returns a *unsigned long int*, so even if it doesn't report an over/underflow
    // we still have to check that the returned value is within the range of an *uint32_t*. On 64-bit
    // platforms the size of these types may be different.
    return endp && *endp == 0 && !errno &&
           n <= std::numeric_limits<uint32_t>::max();
}

bool LegacyParseUInt8(const std::string& str, uint8_t* out)
{
    uint32_t u32;
    if (!LegacyParseUInt32(str, &u32) || u32 > std::numeric_limits<uint8_t>::max()) {
        return false;
    }
    if (out != nullptr) {
        *out = static_cast<uint8_t>(u32);
    }
    return true;
}

bool LegacyParseUInt64(const std::string& str, uint64_t* out)
{
    if (!LegacyParsePrechecks(str))
        return false;
    if (str.size() >= 1 && str[0] == '-') // Reject negative values, unfortunately strtoull accepts these by default if they fit in the range
        return false;
    char* endp = nullptr;
    errno = 0; // strtoull will not set errno if valid
    unsigned long long int n = strtoull(str.c_str(), &endp, 10);
    if (out) *out = (uint64_t)n;
    // Note that strtoull returns a *unsigned long long int*, so even if it doesn't report an over/underflow
    // we still have to check that the returned value is within the range of an *uint64_t*.
    return endp && *endp == 0 && !errno &&
           n <= std::numeric_limits<uint64_t>::max();
}

// For backwards compatibility checking.
int64_t atoi64_legacy(const std::string& str)
{
    return strtoll(str.c_str(), nullptr, 10);
}
}; // namespace

FUZZ_TARGET(string)
{
    FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
    const std::string random_string_1 = fuzzed_data_provider.ConsumeRandomLengthString(32);
    const std::string random_string_2 = fuzzed_data_provider.ConsumeRandomLengthString(32);
    const std::vector<std::string> random_string_vector = ConsumeRandomLengthStringVector(fuzzed_data_provider);

    (void)AmountErrMsg(random_string_1, random_string_2);
    (void)AmountHighWarn(random_string_1);
    BlockFilterType block_filter_type;
    (void)BlockFilterTypeByName(random_string_1, block_filter_type);
    (void)Capitalize(random_string_1);
    (void)CopyrightHolders(random_string_1, fuzzed_data_provider.ConsumeIntegral<unsigned int>(), fuzzed_data_provider.ConsumeIntegral<unsigned int>());
    FeeEstimateMode fee_estimate_mode;
    (void)FeeModeFromString(random_string_1, fee_estimate_mode);
    const auto width{fuzzed_data_provider.ConsumeIntegralInRange<size_t>(1, 1000)};
    (void)FormatParagraph(random_string_1, width, fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, width));
    (void)FormatSubVersion(random_string_1, fuzzed_data_provider.ConsumeIntegral<int>(), random_string_vector);
    (void)GetDescriptorChecksum(random_string_1);
    (void)HelpExampleCli(random_string_1, random_string_2);
    (void)HelpExampleRpc(random_string_1, random_string_2);
    (void)HelpMessageGroup(random_string_1);
    (void)HelpMessageOpt(random_string_1, random_string_2);
    (void)IsDeprecatedRPCEnabled(random_string_1);
    (void)Join(random_string_vector, random_string_1);
    (void)JSONRPCError(fuzzed_data_provider.ConsumeIntegral<int>(), random_string_1);
    const util::Settings settings;
    (void)OnlyHasDefaultSectionSetting(settings, random_string_1, random_string_2);
    (void)ParseNetwork(random_string_1);
    (void)RemovePrefix(random_string_1, random_string_2);
    (void)ResolveErrMsg(random_string_1, random_string_2);
    try {
        (void)RPCConvertNamedValues(random_string_1, random_string_vector);
    } catch (const std::runtime_error&) {
    }
    try {
        (void)RPCConvertValues(random_string_1, random_string_vector);
    } catch (const std::runtime_error&) {
    }
    (void)SanitizeString(random_string_1);
    (void)SanitizeString(random_string_1, fuzzed_data_provider.ConsumeIntegralInRange<int>(0, 3));
#ifndef WIN32
    (void)ShellEscape(random_string_1);
#endif // WIN32
    uint16_t port_out;
    std::string host_out;
    SplitHostPort(random_string_1, port_out, host_out);
    (void)TimingResistantEqual(random_string_1, random_string_2);
    (void)ToLower(random_string_1);
    (void)ToUpper(random_string_1);
    (void)TrimString(random_string_1);
    (void)TrimString(random_string_1, random_string_2);
    (void)urlDecode(random_string_1);
    (void)ContainsNoNUL(random_string_1);
    (void)_(random_string_1.c_str());
    try {
        throw scriptnum_error{random_string_1};
    } catch (const std::runtime_error&) {
    }

    {
        CDataStream data_stream{SER_NETWORK, INIT_PROTO_VERSION};
        std::string s;
        auto limited_string = LIMITED_STRING(s, 10);
        data_stream << random_string_1;
        try {
            data_stream >> limited_string;
            assert(data_stream.empty());
            assert(s.size() <= random_string_1.size());
            assert(s.size() <= 10);
            if (!random_string_1.empty()) {
                assert(!s.empty());
            }
        } catch (const std::ios_base::failure&) {
        }
    }
    {
        CDataStream data_stream{SER_NETWORK, INIT_PROTO_VERSION};
        const auto limited_string = LIMITED_STRING(random_string_1, 10);
        data_stream << limited_string;
        std::string deserialized_string;
        data_stream >> deserialized_string;
        assert(data_stream.empty());
        assert(deserialized_string == random_string_1);
    }
    {
        int64_t amount_out;
        (void)ParseFixedPoint(random_string_1, fuzzed_data_provider.ConsumeIntegralInRange<int>(0, 1024), &amount_out);
    }
    {
        const auto single_split{SplitString(random_string_1, fuzzed_data_provider.ConsumeIntegral<char>())};
        assert(single_split.size() >= 1);
        const auto any_split{SplitString(random_string_1, random_string_2)};
        assert(any_split.size() >= 1);
    }
    {
        (void)Untranslated(random_string_1);
        const bilingual_str bs1{random_string_1, random_string_2};
        const bilingual_str bs2{random_string_2, random_string_1};
        (void)(bs1 + bs2);
    }
    {
        int32_t i32;
        int64_t i64;
        uint32_t u32;
        uint64_t u64;
        uint8_t u8;
        const bool ok_i32 = ParseInt32(random_string_1, &i32);
        const bool ok_i64 = ParseInt64(random_string_1, &i64);
        const bool ok_u32 = ParseUInt32(random_string_1, &u32);
        const bool ok_u64 = ParseUInt64(random_string_1, &u64);
        const bool ok_u8 = ParseUInt8(random_string_1, &u8);

        int32_t i32_legacy;
        int64_t i64_legacy;
        uint32_t u32_legacy;
        uint64_t u64_legacy;
        uint8_t u8_legacy;
        const bool ok_i32_legacy = LegacyParseInt32(random_string_1, &i32_legacy);
        const bool ok_i64_legacy = LegacyParseInt64(random_string_1, &i64_legacy);
        const bool ok_u32_legacy = LegacyParseUInt32(random_string_1, &u32_legacy);
        const bool ok_u64_legacy = LegacyParseUInt64(random_string_1, &u64_legacy);
        const bool ok_u8_legacy = LegacyParseUInt8(random_string_1, &u8_legacy);

        assert(ok_i32 == ok_i32_legacy);
        assert(ok_i64 == ok_i64_legacy);
        assert(ok_u32 == ok_u32_legacy);
        assert(ok_u64 == ok_u64_legacy);
        assert(ok_u8 == ok_u8_legacy);

        if (ok_i32) {
            assert(i32 == i32_legacy);
        }
        if (ok_i64) {
            assert(i64 == i64_legacy);
        }
        if (ok_u32) {
            assert(u32 == u32_legacy);
        }
        if (ok_u64) {
            assert(u64 == u64_legacy);
        }
        if (ok_u8) {
            assert(u8 == u8_legacy);
        }
    }

    {
        const int locale_independent_atoi_result = LocaleIndependentAtoi<int>(random_string_1);
        const int64_t atoi64_result = atoi64_legacy(random_string_1);
        assert(locale_independent_atoi_result == std::clamp<int64_t>(atoi64_result, std::numeric_limits<int>::min(), std::numeric_limits<int>::max()));
    }

    {
        const int64_t atoi64_result = atoi64_legacy(random_string_1);
        const int64_t locale_independent_atoi_result = LocaleIndependentAtoi<int64_t>(random_string_1);
        assert(atoi64_result == locale_independent_atoi_result);
    }
}
