//     __ _____ _____ _____

//  __|  |   __|     |   | |  JSON for Modern C++ (supporting code)

// |  |  |__   |  |  | | | |  version 3.12.0

// |_____|_____|_____|_|___|  https://github.com/nlohmann/json

//

// SPDX-FileCopyrightText: 2013-2026 Niels Lohmann <https://nlohmann.me>

// SPDX-License-Identifier: MIT

/*

This file implements a parser test suitable for fuzz testing. Given a byte

array data, it performs the following steps:

- j1 = from_bjdata(data)

- vec = to_bjdata(j1)

- j2 = from_bjdata(vec)

- assert(j1 == j2)

- vec2 = to_bjdata(j1, use_size = true, use_type = false)

- j3 = from_bjdata(vec2)

- assert(j1 == j3)

- vec3 = to_bjdata(j1, use_size = true, use_type = true)

- j4 = from_bjdata(vec3)

- assert(j1 == j4)

The provided function `LLVMFuzzerTestOneInput` can be used in different fuzzer

drivers.

*/

#include <iostream>

#include <sstream>

#include <nlohmann/json.hpp>

using json = nlohmann::json;

// see http://llvm.org/docs/LibFuzzer.html

extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size)

{

    try

    {

        // step 1: parse input

        std::vector<uint8_t> const vec1(data, data + size);

        json const j1 = json::from_bjdata(vec1);

        try

        {

            // step 2.1: round trip without adding size annotations to container types

            std::vector<uint8_t> const vec2 = json::to_bjdata(j1, false, false);

            // step 2.2: round trip with adding size annotations but without adding type annotations to container types

            std::vector<uint8_t> const vec3 = json::to_bjdata(j1, true, false);

            // step 2.3: round trip with adding size as well as type annotations to container types

            std::vector<uint8_t> const vec4 = json::to_bjdata(j1, true, true);

            // parse serialization

            json const j2 = json::from_bjdata(vec2);

            json const j3 = json::from_bjdata(vec3);

            json const j4 = json::from_bjdata(vec4);

            // serializations must match

            assert(json::to_bjdata(j2, false, false) == vec2);

            assert(json::to_bjdata(j3, true, false) == vec3);

            assert(json::to_bjdata(j4, true, true) == vec4);

        }

        catch (const json::parse_error&)

        {

            // parsing a BJData serialization must not fail

            assert(false);

        }

    }

    catch (const json::parse_error&)

    {

        // parse errors are ok, because input may be random bytes

    }

    catch (const json::type_error&)

    {

        // type errors can occur during parsing, too

    }

    catch (const json::out_of_range&)

    {

        // out of range errors may happen if provided sizes are excessive

    }

    // return 0 - non-zero return values are reserved for future use

    return 0;

}