text:
#include "tiny_gltf.h"

#include <algorithm>
//#include <cassert>
#ifndef TINYGLTF_NO_FS
#include <cstdio>
#include <fstream>
#endif
#include <sstream>

#ifdef __clang__
// Disable some warnings for external files.
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wfloat-equal"
#pragma clang diagnostic ignored "-Wexit-time-destructors"
#pragma clang diagnostic ignored "-Wconversion"
#pragma clang diagnostic ignored "-Wold-style-cast"
#pragma clang diagnostic ignored "-Wglobal-constructors"
#if __has_warning("-Wreserved-id-macro")
#pragma clang diagnostic ignored "-Wreserved-id-macro"
#endif
#pragma clang diagnostic ignored "-Wdisabled-macro-expansion"
#pragma clang diagnostic ignored "-Wpadded"
#pragma clang diagnostic ignored "-Wc++98-compat"
#pragma clang diagnostic ignored "-Wc++98-compat-pedantic"
#pragma clang diagnostic ignored "-Wdocumentation-unknown-command"
#pragma clang diagnostic ignored "-Wswitch-enum"
#pragma clang diagnostic ignored "-Wimplicit-fallthrough"
#pragma clang diagnostic ignored "-Wweak-vtables"
#pragma clang diagnostic ignored "-Wcovered-switch-default"
#if __has_warning("-Wdouble-promotion")
#pragma clang diagnostic ignored "-Wdouble-promotion"
#endif
#if __has_warning("-Wcomma")
#pragma clang diagnostic ignored "-Wcomma"
#endif
#if __has_warning("-Wzero-as-null-pointer-constant")
#pragma clang diagnostic ignored "-Wzero-as-null-pointer-constant"
#endif
#if __has_warning("-Wcast-qual")
#pragma clang diagnostic ignored "-Wcast-qual"
#endif
#if __has_warning("-Wmissing-variable-declarations")
#pragma clang diagnostic ignored "-Wmissing-variable-declarations"
#endif
#if __has_warning("-Wmissing-prototypes")
#pragma clang diagnostic ignored "-Wmissing-prototypes"
#endif
#if __has_warning("-Wcast-align")
#pragma clang diagnostic ignored "-Wcast-align"
#endif
#if __has_warning("-Wnewline-eof")
#pragma clang diagnostic ignored "-Wnewline-eof"
#endif
#if __has_warning("-Wunused-parameter")
#pragma clang diagnostic ignored "-Wunused-parameter"
#endif
#if __has_warning("-Wmismatched-tags")
#pragma clang diagnostic ignored "-Wmismatched-tags"
#endif
#if __has_warning("-Wextra-semi-stmt")
#pragma clang diagnostic ignored "-Wextra-semi-stmt"
#endif
#endif

// Disable GCC warnigs
#ifdef __GNUC__
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wtype-limits"
#endif  // __GNUC__

#ifndef TINYGLTF_NO_INCLUDE_JSON
#ifndef TINYGLTF_USE_RAPIDJSON
#include "json.hpp"
#else
#include "document.h"
#include "prettywriter.h"
#include "rapidjson.h"
#include "stringbuffer.h"
#include "writer.h"
#endif
#endif

#ifdef TINYGLTF_ENABLE_DRACO
#include "draco/compression/decode.h"
#include "draco/core/decoder_buffer.h"
#endif

#ifndef TINYGLTF_NO_STB_IMAGE
#ifndef TINYGLTF_NO_INCLUDE_STB_IMAGE
#include "stb/stb_image.h"
#endif
#endif

#ifndef TINYGLTF_NO_STB_IMAGE_WRITE
#ifndef TINYGLTF_NO_INCLUDE_STB_IMAGE_WRITE
#include "stb/stb_image_write.h"
#endif
#endif

#ifdef __clang__
#pragma clang diagnostic pop
#endif

#ifdef __GNUC__
#pragma GCC diagnostic pop
#endif

#ifdef _WIN32

// issue 143.
// Define NOMINMAX to avoid min/max defines,
// but undef it after included windows.h
#ifndef NOMINMAX
#define TINYGLTF_INTERNAL_NOMINMAX
#define NOMINMAX
#endif

#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#define TINYGLTF_INTERNAL_WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>  // include API for expanding a file path

#ifdef TINYGLTF_INTERNAL_WIN32_LEAN_AND_MEAN
#undef WIN32_LEAN_AND_MEAN
#endif

#if defined(TINYGLTF_INTERNAL_NOMINMAX)
#undef NOMINMAX
#endif

#if defined(__GLIBCXX__)  // mingw

#include <fcntl.h>  // _O_RDONLY

#include <ext/stdio_filebuf.h>  // fstream (all sorts of IO stuff) + stdio_filebuf (=streambuf)

#endif

#elif !defined(__ANDROID__)
#include <wordexp.h>
#endif

#if defined(__sparcv9)
// Big endian
#else
#if (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) || MINIZ_X86_OR_X64_CPU
#define TINYGLTF_LITTLE_ENDIAN 1
#endif
#endif

namespace {
#ifdef TINYGLTF_USE_RAPIDJSON

#ifdef TINYGLTF_USE_RAPIDJSON_CRTALLOCATOR
// This uses the RapidJSON CRTAllocator.  It is thread safe and multiple
// documents may be active at once.
using json =
    rapidjson::GenericValue<rapidjson::UTF8<>, rapidjson::CrtAllocator>;
using json_const_iterator = json::ConstMemberIterator;
using json_const_array_iterator = json const *;
using JsonDocument =
    rapidjson::GenericDocument<rapidjson::UTF8<>, rapidjson::CrtAllocator>;
rapidjson::CrtAllocator s_CrtAllocator;  // stateless and thread safe
rapidjson::CrtAllocator &GetAllocator() { return s_CrtAllocator; }
#else
// This uses the default RapidJSON MemoryPoolAllocator.  It is very fast, but
// not thread safe. Only a single JsonDocument may be active at any one time,
// meaning only a single gltf load/save can be active any one time.
using json = rapidjson::Value;
using json_const_iterator = json::ConstMemberIterator;
using json_const_array_iterator = json const *;
rapidjson::Document *s_pActiveDocument = nullptr;
rapidjson::Document::AllocatorType &GetAllocator() {
  assert(s_pActiveDocument);  // Root json node must be JsonDocument type
  return s_pActiveDocument->GetAllocator();
}

#ifdef __clang__
#pragma clang diagnostic push
// Suppress JsonDocument(JsonDocument &&rhs) noexcept
#pragma clang diagnostic ignored "-Wunused-member-function"
#endif

struct JsonDocument : public rapidjson::Document {
  JsonDocument() {
    assert(s_pActiveDocument ==
           nullptr);  // When using default allocator, only one document can be
                      // active at a time, if you need multiple active at once,
                      // define TINYGLTF_USE_RAPIDJSON_CRTALLOCATOR
    s_pActiveDocument = this;
  }
  JsonDocument(const JsonDocument &) = delete;
  JsonDocument(JsonDocument &&rhs) noexcept
      : rapidjson::Document(std::move(rhs)) {
    s_pActiveDocument = this;
    rhs.isNil = true;
  }
  ~JsonDocument() {
    if (!isNil) {
      s_pActiveDocument = nullptr;
    }
  }

 private:
  bool isNil = false;
};

#ifdef __clang__
#pragma clang diagnostic pop
#endif

#endif  // TINYGLTF_USE_RAPIDJSON_CRTALLOCATOR

#else
using nlohmann::json;
using json_const_iterator = json::const_iterator;
using json_const_array_iterator = json_const_iterator;
using JsonDocument = json;
#endif

void JsonParse(JsonDocument &doc, const char *str, size_t length,
               bool throwExc = false) {
#ifdef TINYGLTF_USE_RAPIDJSON
  (void)throwExc;
  doc.Parse(str, length);
#else
  doc = json::parse(str, str + length, nullptr, throwExc);
#endif
}
}  // namespace

#ifdef __APPLE__
#include "TargetConditionals.h"
#endif

#ifdef __clang__
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wc++98-compat"
#endif

namespace tinygltf {

// Equals function for Value, for recursivity
static bool Equals(const tinygltf::Value &one, const tinygltf::Value &other) {
  if (one.Type() != other.Type()) return false;

  switch (one.Type()) {
    case NULL_TYPE:
      return true;
    case BOOL_TYPE:
      return one.Get<bool>() == other.Get<bool>();
    case REAL_TYPE:
      return TINYGLTF_DOUBLE_EQUAL(one.Get<double>(), other.Get<double>());
    case INT_TYPE:
      return one.Get<int>() == other.Get<int>();
    case OBJECT_TYPE: {
      auto oneObj = one.Get<tinygltf::Value::Object>();
      auto otherObj = other.Get<tinygltf::Value::Object>();
      if (oneObj.size() != otherObj.size()) return false;
      for (auto &it : oneObj) {
        auto otherIt = otherObj.find(it.first);
        if (otherIt == otherObj.end()) return false;

        if (!Equals(it.second, otherIt->second)) return false;
      }
      return true;
    }
    case ARRAY_TYPE: {
      if (one.Size() != other.Size()) return false;
      for (int i = 0; i < int(one.Size()); ++i)
        if (!Equals(one.Get(i), other.Get(i))) return false;
      return true;
    }
    case STRING_TYPE:
      return one.Get<std::string>() == other.Get<std::string>();
    case BINARY_TYPE:
      return one.Get<std::vector<unsigned char> >() ==
             other.Get<std::vector<unsigned char> >();
    default: {
      // unhandled type
      return false;
    }
  }
}

// Equals function for std::vector<double> using TINYGLTF_DOUBLE_EPSILON
static bool Equals(const std::vector<double> &one,
                   const std::vector<double> &other) {
  if (one.size() != other.size()) return false;
  for (int i = 0; i < int(one.size()); ++i) {
    if (!TINYGLTF_DOUBLE_EQUAL(one[size_t(i)], other[size_t(i)])) return false;
  }
  return true;
}

bool Accessor::operator==(const Accessor &other) const {
  return this->bufferView == other.bufferView &&
         this->byteOffset == other.byteOffset &&
         this->componentType == other.componentType &&
         this->count == other.count && this->extensions == other.extensions &&
         this->extras == other.extras &&
         Equals(this->maxValues, other.maxValues) &&
         Equals(this->minValues, other.minValues) && this->name == other.name &&
         this->normalized == other.normalized && this->type == other.type;
}
bool Animation::operator==(const Animation &other) const {
  return this->channels == other.channels &&
         this->extensions == other.extensions && this->extras == other.extras &&
         this->name == other.name && this->samplers == other.samplers;
}
bool AnimationChannel::operator==(const AnimationChannel &other) const {
  return this->extensions == other.extensions && this->extras == other.extras &&
         this->target_node == other.target_node &&
         this->target_path == other.target_path &&
         this->sampler == other.sampler;
}
bool AnimationSampler::operator==(const AnimationSampler &other) const {
  return this->extras == other.extras && this->extensions == other.extensions &&
         this->input == other.input &&
         this->interpolation == other.interpolation &&
         this->output == other.output;
}
bool Asset::operator==(const Asset &other) const {
  return this->copyright == other.copyright &&
         this->extensions == other.extensions && this->extras == other.extras &&
         this->generator == other.generator &&
         this->minVersion == other.minVersion && this->version == other.version;
}
bool Buffer::operator==(const Buffer &other) const {
  return this->data == other.data && this->extensions == other.extensions &&
         this->extras == other.extras && this->name == other.name &&
         this->uri == other.uri;
}
bool BufferView::operator==(const BufferView &other) const {
  return this->buffer == other.buffer && this->byteLength == other.byteLength &&
         this->byteOffset == other.byteOffset &&
         this->byteStride == other.byteStride && this->name == other.name &&
         this->target == other.target && this->extensions == other.extensions &&
         this->extras == other.extras &&
         this->dracoDecoded == other.dracoDecoded;
}
bool Camera::operator==(const Camera &other) const {
  return this->name == other.name && this->extensions == other.extensions &&
         this->extras == other.extras &&
         this->orthographic == other.orthographic &&
         this->perspective == other.perspective && this->type == other.type;
}
bool Image::operator==(const Image &other) const {
  return this->bufferView == other.bufferView &&
         this->component == other.component &&
         this->extensions == other.extensions && this->extras == other.extras &&
         this->height == other.height && this->image == other.image &&
         this->mimeType == other.mimeType && this->name == other.name &&
         this->uri == other.uri && this->width == other.width;
}
bool Light::operator==(const Light &other) const {
  return Equals(this->color, other.color) && this->name == other.name &&
         this->type == other.type;
}
bool Material::operator==(const Material &other) const {
  return (this->pbrMetallicRoughness == other.pbrMetallicRoughness) &&
         (this->normalTexture == other.normalTexture) &&
         (this->occlusionTexture == other.occlusionTexture) &&
         (this->emissiveTexture == other.emissiveTexture) &&
         Equals(this->emissiveFactor, other.emissiveFactor) &&
         (this->alphaMode == other.alphaMode) &&
         TINYGLTF_DOUBLE_EQUAL(this->alphaCutoff, other.alphaCutoff) &&
         (this->doubleSided == other.doubleSided) &&
         (this->extensions == other.extensions) &&
         (this->extras == other.extras) && (this->values == other.values) &&
         (this->additionalValues == other.additionalValues) &&
         (this->name == other.name);
}
bool Mesh::operator==(const Mesh &other) const {
  return this->extensions == other.extensions && this->extras == other.extras &&
         this->name == other.name && Equals(this->weights, other.weights) &&
         this->primitives == other.primitives;
}
bool Model::operator==(const Model &other) const {
  return this->accessors == other.accessors &&
         this->animations == other.animations && this->asset == other.asset &&
         this->buffers == other.buffers &&
         this->bufferViews == other.bufferViews &&
         this->cameras == other.cameras &&
         this->defaultScene == other.defaultScene &&
         this->extensions == other.extensions &&
         this->extensionsRequired == other.extensionsRequired &&
         this->extensionsUsed == other.extensionsUsed &&
         this->extras == other.extras && this->images == other.images &&
         this->lights == other.lights && this->materials == other.materials &&
         this->meshes == other.meshes && this->nodes == other.nodes &&
         this->samplers == other.samplers && this->scenes == other.scenes &&
         this->skins == other.skins && this->textures == other.textures;
}
bool Node::operator==(const Node &other) const {
  return this->camera == other.camera && this->children == other.children &&
         this->extensions == other.extensions && this->extras == other.extras &&
         Equals(this->matrix, other.matrix) && this->mesh == other.mesh &&
         this->name == other.name && Equals(this->rotation, other.rotation) &&
         Equals(this->scale, other.scale) && this->skin == other.skin &&
         Equals(this->translation, other.translation) &&
         Equals(this->weights, other.weights);
}
bool SpotLight::operator==(const SpotLight &other) const {
  return this->extensions == other.extensions && this->extras == other.extras &&
         TINYGLTF_DOUBLE_EQUAL(this->innerConeAngle, other.innerConeAngle) &&
         TINYGLTF_DOUBLE_EQUAL(this->outerConeAngle, other.outerConeAngle);
}
bool OrthographicCamera::operator==(const OrthographicCamera &other) const {
  return this->extensions == other.extensions && this->extras == other.extras &&
         TINYGLTF_DOUBLE_EQUAL(this->xmag, other.xmag) &&
         TINYGLTF_DOUBLE_EQUAL(this->ymag, other.ymag) &&
         TINYGLTF_DOUBLE_EQUAL(this->zfar, other.zfar) &&
         TINYGLTF_DOUBLE_EQUAL(this->znear, other.znear);
}
bool Parameter::operator==(const Parameter &other) const {
  if (this->bool_value != other.bool_value ||
      this->has_number_value != other.has_number_value)
    return false;

  if (!TINYGLTF_DOUBLE_EQUAL(this->number_value, other.number_value))
    return false;

  if (this->json_double_value.size() != other.json_double_value.size())
    return false;
  for (auto &it : this->json_double_value) {
    auto otherIt = other.json_double_value.find(it.first);
    if (otherIt == other.json_double_value.end()) return false;

    if (!TINYGLTF_DOUBLE_EQUAL(it.second, otherIt->second)) return false;
  }

  if (!Equals(this->number_array, other.number_array)) return false;

  if (this->string_value != other.string_value) return false;

  return true;
}
bool PerspectiveCamera::operator==(const PerspectiveCamera &other) const {
  return TINYGLTF_DOUBLE_EQUAL(this->aspectRatio, other.aspectRatio) &&
         this->extensions == other.extensions && this->extras == other.extras &&
         TINYGLTF_DOUBLE_EQUAL(this->yfov, other.yfov) &&
         TINYGLTF_DOUBLE_EQUAL(this->zfar, other.zfar) &&
         TINYGLTF_DOUBLE_EQUAL(this->znear, other.znear);
}
bool Primitive::operator==(const Primitive &other) const {
  return this->attributes == other.attributes && this->extras == other.extras &&
         this->indices == other.indices && this->material == other.material &&
         this->mode == other.mode && this->targets == other.targets;
}
bool Sampler::operator==(const Sampler &other) const {
  return this->extensions == other.extensions && this->extras == other.extras &&
         this->magFilter == other.magFilter &&
         this->minFilter == other.minFilter && this->name == other.name &&
         this->wrapR == other.wrapR && this->wrapS == other.wrapS &&
         this->wrapT == other.wrapT;
}
bool Scene::operator==(const Scene &other) const {
  return this->extensions == other.extensions && this->extras == other.extras &&
         this->name == other.name && this->nodes == other.nodes;
}
bool Skin::operator==(const Skin &other) const {
  return this->extensions == other.extensions && this->extras == other.extras &&
         this->inverseBindMatrices == other.inverseBindMatrices &&
         this->joints == other.joints && this->name == other.name &&
         this->skeleton == other.skeleton;
}
bool Texture::operator==(const Texture &other) const {
  return this->extensions == other.extensions && this->extras == other.extras &&
         this->name == other.name && this->sampler == other.sampler &&
         this->source == other.source;
}
bool TextureInfo::operator==(const TextureInfo &other) const {
  return this->extensions == other.extensions && this->extras == other.extras &&
         this->index == other.index && this->texCoord == other.texCoord;
}
bool NormalTextureInfo::operator==(const NormalTextureInfo &other) const {
  return this->extensions == other.extensions && this->extras == other.extras &&
         this->index == other.index && this->texCoord == other.texCoord &&
         TINYGLTF_DOUBLE_EQUAL(this->scale, other.scale);
}
bool OcclusionTextureInfo::operator==(const OcclusionTextureInfo &other) const {
  return this->extensions == other.extensions && this->extras == other.extras &&
         this->index == other.index && this->texCoord == other.texCoord &&
         TINYGLTF_DOUBLE_EQUAL(this->strength, other.strength);
}
bool PbrMetallicRoughness::operator==(const PbrMetallicRoughness &other) const {
  return this->extensions == other.extensions && this->extras == other.extras &&
         (this->baseColorTexture == other.baseColorTexture) &&
         (this->metallicRoughnessTexture == other.metallicRoughnessTexture) &&
         Equals(this->baseColorFactor, other.baseColorFactor) &&
         TINYGLTF_DOUBLE_EQUAL(this->metallicFactor, other.metallicFactor) &&
         TINYGLTF_DOUBLE_EQUAL(this->roughnessFactor, other.roughnessFactor);
}
bool Value::operator==(const Value &other) const {
  return Equals(*this, other);
}

static void swap4(unsigned int *val) {
#ifdef TINYGLTF_LITTLE_ENDIAN
  (void)val;
#else
  unsigned int tmp = *val;
  unsigned char *dst = reinterpret_cast<unsigned char *>(val);
  unsigned char *src = reinterpret_cast<unsigned char *>(&tmp);

  dst[0] = src[3];
  dst[1] = src[2];
  dst[2] = src[1];
  dst[3] = src[0];
#endif
}

static std::string JoinPath(const std::string &path0,
                            const std::string &path1) {
  if (path0.empty()) {
    return path1;
  } else {
    // check '/'
    char lastChar = *path0.rbegin();
    if (lastChar != '/') {
      return path0 + std::string("/") + path1;
    } else {
      return path0 + path1;
    }
  }
}

static std::string FindFile(const std::vector<std::string> &paths,
                            const std::string &filepath, FsCallbacks *fs) {
  if (fs == nullptr || fs->ExpandFilePath == nullptr ||
      fs->FileExists == nullptr) {
    // Error, fs callback[s] missing
    return std::string();
  }

  for (size_t i = 0; i < paths.size(); i++) {
    std::string absPath =
        fs->ExpandFilePath(JoinPath(paths[i], filepath), fs->user_data);
    if (fs->FileExists(absPath, fs->user_data)) {
      return absPath;
    }
  }

  return std::string();
}

static std::string GetFilePathExtension(const std::string &FileName) {
  if (FileName.find_last_of(".") != std::string::npos)
    return FileName.substr(FileName.find_last_of(".") + 1);
  return "";
}

static std::string GetBaseDir(const std::string &filepath) {
  if (filepath.find_last_of("/\\") != std::string::npos)
    return filepath.substr(0, filepath.find_last_of("/\\"));
  return "";
}

// https://stackoverflow.com/questions/8520560/get-a-file-name-from-a-path
static std::string GetBaseFilename(const std::string &filepath) {
  return filepath.substr(filepath.find_last_of("/\\") + 1);
}

std::string base64_encode(unsigned char const *, unsigned int len);
std::string base64_decode(std::string const &s);

#ifdef __clang__
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wsign-conversion"
#pragma clang diagnostic ignored "-Wconversion"
#endif

static inline bool is_base64(unsigned char c) {
  return (isalnum(c) || (c == '+') || (c == '/'));
}

std::string base64_encode(unsigned char const *bytes_to_encode,
                          unsigned int in_len) {
  std::string ret;
  int i = 0;
  int j = 0;
  unsigned char char_array_3[3];
  unsigned char char_array_4[4];

  const char *base64_chars =
      "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
      "abcdefghijklmnopqrstuvwxyz"
      "0123456789+/";

  while (in_len--) {
    char_array_3[i++] = *(bytes_to_encode++);
    if (i == 3) {
      char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
      char_array_4[1] =
          ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
      char_array_4[2] =
          ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
      char_array_4[3] = char_array_3[2] & 0x3f;

      for (i = 0; (i < 4); i++) ret += base64_chars[char_array_4[i]];
      i = 0;
    }
  }

  if (i) {
    for (j = i; j < 3; j++) char_array_3[j] = '\0';

    char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
    char_array_4[1] =
        ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
    char_array_4[2] =
        ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);

    for (j = 0; (j < i + 1); j++) ret += base64_chars[char_array_4[j]];

    while ((i++ < 3)) ret += '=';
  }

  return ret;
}

std::string base64_decode(std::string const &encoded_string) {
  int in_len = static_cast<int>(encoded_string.size());
  int i = 0;
  int j = 0;
  int in_ = 0;
  unsigned char char_array_4[4], char_array_3[3];
  std::string ret;

  const std::string base64_chars =
      "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
      "abcdefghijklmnopqrstuvwxyz"
      "0123456789+/";

  while (in_len-- && (encoded_string[in_] != '=') &&
         is_base64(encoded_string[in_])) {
    char_array_4[i++] = encoded_string[in_];
    in_++;
    if (i == 4) {
      for (i = 0; i < 4; i++)
        char_array_4[i] =
            static_cast<unsigned char>(base64_chars.find(char_array_4[i]));

      char_array_3[0] =
          (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
      char_array_3[1] =
          ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
      char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];

      for (i = 0; (i < 3); i++) ret += char_array_3[i];
      i = 0;
    }
  }

  if (i) {
    for (j = i; j < 4; j++) char_array_4[j] = 0;

    for (j = 0; j < 4; j++)
      char_array_4[j] =
          static_cast<unsigned char>(base64_chars.find(char_array_4[j]));

    char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
    char_array_3[1] =
        ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
    char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];

    for (j = 0; (j < i - 1); j++) ret += char_array_3[j];
  }

  return ret;
}
#ifdef __clang__
#pragma clang diagnostic pop
#endif

// https://github.com/syoyo/tinygltf/issues/228
// TODO(syoyo): Use uriparser https://uriparser.github.io/ for stricter Uri
// decoding?
//
// https://stackoverflow.com/questions/18307429/encode-decode-url-in-c
// http://dlib.net/dlib/server/server_http.cpp.html

// --- dlib beign ------------------------------------------------------------
// Copyright (C) 2003  Davis E. King (davis@dlib.net)
// License: Boost Software License   See LICENSE.txt for the full license.

namespace dlib {

#if 0
        inline unsigned char to_hex( unsigned char x )
        {
            return x + (x > 9 ? ('A'-10) : '0');
        }

        const std::string urlencode( const std::string& s )
        {
            std::ostringstream os;

            for ( std::string::const_iterator ci = s.begin(); ci != s.end(); ++ci )
            {
                if ( (*ci >= 'a' && *ci <= 'z') ||
                     (*ci >= 'A' && *ci <= 'Z') ||
                     (*ci >= '0' && *ci <= '9') )
                { // allowed
                    os << *ci;
                }
                else if ( *ci == ' ')
                {
                    os << '+';
                }
                else
                {
                    os << '%' << to_hex(static_cast<unsigned char>(*ci >> 4)) << to_hex(static_cast<unsigned char>(*ci % 16));
                }
            }

            return os.str();
        }
#endif

inline unsigned char from_hex(unsigned char ch) {
  if (ch <= '9' && ch >= '0')
    ch -= '0';
  else if (ch <= 'f' && ch >= 'a')
    ch -= 'a' - 10;
  else if (ch <= 'F' && ch >= 'A')
    ch -= 'A' - 10;
  else
    ch = 0;
  return ch;
}

static const std::string urldecode(const std::string &str) {
  using namespace std;
  string result;
  string::size_type i;
  for (i = 0; i < str.size(); ++i) {
    if (str[i] == '+') {
      result += ' ';
    } else if (str[i] == '%' && str.size() > i + 2) {
      const unsigned char ch1 =
          from_hex(static_cast<unsigned char>(str[i + 1]));
      const unsigned char ch2 =
          from_hex(static_cast<unsigned char>(str[i + 2]));
      const unsigned char ch = static_cast<unsigned char>((ch1 << 4) | ch2);
      result += static_cast<char>(ch);
      i += 2;
    } else {
      result += str[i];
    }
  }
  return result;
}

}  // namespace dlib
// --- dlib end --------------------------------------------------------------

static bool LoadExternalFile(std::vector<unsigned char> *out, std::string *err,
                             std::string *warn, const std::string &filename,
                             const std::string &basedir, bool required,
                             size_t reqBytes, bool checkSize, FsCallbacks *fs) {
  if (fs == nullptr || fs->FileExists == nullptr ||
      fs->ExpandFilePath == nullptr || fs->ReadWholeFile == nullptr) {
    // This is a developer error, assert() ?
    if (err) {
      (*err) += "FS callback[s] not set\n";
    }
    return false;
  }

  std::string *failMsgOut = required ? err : warn;

  out->clear();

  std::vector<std::string> paths;
  paths.push_back(basedir);
  paths.push_back(".");

  std::string filepath = FindFile(paths, filename, fs);
  if (filepath.empty() || filename.empty()) {
    if (failMsgOut) {
      (*failMsgOut) += "File not found : " + filename + "\n";
    }
    return false;
  }

  std::vector<unsigned char> buf;
  std::string fileReadErr;
  bool fileRead =
      fs->ReadWholeFile(&buf, &fileReadErr, filepath, fs->user_data);
  if (!fileRead) {
    if (failMsgOut) {
      (*failMsgOut) +=
          "File read error : " + filepath + " : " + fileReadErr + "\n";
    }
    return false;
  }

  size_t sz = buf.size();
  if (sz == 0) {
    if (failMsgOut) {
      (*failMsgOut) += "File is empty : " + filepath + "\n";
    }
    return false;
  }

  if (checkSize) {
    if (reqBytes == sz) {
      out->swap(buf);
      return true;
    } else {
      std::stringstream ss;
      ss << "File size mismatch : " << filepath << ", requestedBytes "
         << reqBytes << ", but got " << sz << std::endl;
      if (failMsgOut) {
        (*failMsgOut) += ss.str();
      }
      return false;
    }
  }

  out->swap(buf);
  return true;
}

void TinyGLTF::SetImageLoader(LoadImageDataFunction func, void *user_data) {
  LoadImageData = func;
  load_image_user_data_ = user_data;
}

#ifndef TINYGLTF_NO_STB_IMAGE
bool LoadImageData(Image *image, const int image_idx, std::string *err,
                   std::string *warn, int req_width, int req_height,
                   const unsigned char *bytes, int size, void *user_data) {
  (void)user_data;
  (void)warn;

  int w = 0, h = 0, comp = 0, req_comp = 0;

  unsigned char *data = nullptr;

  // force 32-bit textures for common Vulkan compatibility. It appears that
  // some GPU drivers do not support 24-bit images for Vulkan
  req_comp = 4;
  int bits = 8;
  int pixel_type = TINYGLTF_COMPONENT_TYPE_UNSIGNED_BYTE;

  // It is possible that the image we want to load is a 16bit per channel image
  // We are going to attempt to load it as 16bit per channel, and if it worked,
  // set the image data accodingly. We are casting the returned pointer into
  // unsigned char, because we are representing "bytes". But we are updating
  // the Image metadata to signal that this image uses 2 bytes (16bits) per
  // channel:
  if (stbi_is_16_bit_from_memory(bytes, size)) {
    data = reinterpret_cast<unsigned char *>(
        stbi_load_16_from_memory(bytes, size, &w, &h, &comp, req_comp));
    if (data) {
      bits = 16;
      pixel_type = TINYGLTF_COMPONENT_TYPE_UNSIGNED_SHORT;
    }
  }

  // at this point, if data is still NULL, it means that the image wasn't
  // 16bit per channel, we are going to load it as a normal 8bit per channel
  // mage as we used to do:
  // if image cannot be decoded, ignore parsing and keep it by its path
  // don't break in this case
  // FIXME we should only enter this function if the image is embedded. If
  // image->uri references
  // an image file, it should be left as it is. Image loading should not be
  // mandatory (to support other formats)
  if (!data) data = stbi_load_from_memory(bytes, size, &w, &h, &comp, req_comp);
  if (!data) {
    // NOTE: you can use `warn` instead of `err`
    if (err) {
      (*err) +=
          "Unknown image format. STB cannot decode image data for image[" +
          std::to_string(image_idx) + "] name = \"" + image->name + "\".\n";
    }
    return false;
  }

  if ((w < 1) || (h < 1)) {
    stbi_image_free(data);
    if (err) {
      (*err) += "Invalid image data for image[" + std::to_string(image_idx) +
                "] name = \"" + image->name + "\"\n";
    }
    return false;
  }

  if (req_width > 0) {
    if (req_width != w) {
      stbi_image_free(data);
      if (err) {
        (*err) += "Image width mismatch for image[" +
                  std::to_string(image_idx) + "] name = \"" + image->name +
                  "\"\n";
      }
      return false;
    }
  }

  if (req_height > 0) {
    if (req_height != h) {
      stbi_image_free(data);
      if (err) {
        (*err) += "Image height mismatch. for image[" +
                  std::to_string(image_idx) + "] name = \"" + image->name +
                  "\"\n";
      }
      return false;
    }
  }

  image->width = w;
  image->height = h;
  image->component = req_comp;
  image->bits = bits;
  image->pixel_type = pixel_type;
  image->image.resize(static_cast<size_t>(w * h * req_comp) * size_t(bits / 8));
  std::copy(data, data + w * h * req_comp * (bits / 8), image->image.begin());
  stbi_image_free(data);

  return true;
}
#endif

void TinyGLTF::SetImageWriter(WriteImageDataFunction func, void *user_data) {
  WriteImageData = func;
  write_image_user_data_ = user_data;
}

#ifndef TINYGLTF_NO_STB_IMAGE_WRITE
static void WriteToMemory_stbi(void *context, void *data, int size) {
  std::vector<unsigned char> *buffer =
      reinterpret_cast<std::vector<unsigned char> *>(context);

  unsigned char *pData = reinterpret_cast<unsigned char *>(data);

  buffer->insert(buffer->end(), pData, pData + size);
}

bool WriteImageData(const std::string *basepath, const std::string *filename,
                    Image *image, bool embedImages, void *fsPtr) {
  const std::string ext = GetFilePathExtension(*filename);

  // Write image to temporary buffer
  std::string header;
  std::vector<unsigned char> data;

  if (ext == "png") {
    if ((image->bits != 8) ||
        (image->pixel_type != TINYGLTF_COMPONENT_TYPE_UNSIGNED_BYTE)) {
      // Unsupported pixel format
      return false;
    }

    if (!stbi_write_png_to_func(WriteToMemory_stbi, &data, image->width,
                                image->height, image->component,
                                &image->image[0], 0)) {
      return false;
    }
    header = "data:image/png;base64,";
  } else if (ext == "jpg") {
    if (!stbi_write_jpg_to_func(WriteToMemory_stbi, &data, image->width,
                                image->height, image->component,
                                &image->image[0], 100)) {
      return false;
    }
    header = "data:image/jpeg;base64,";
  } else if (ext == "bmp") {
    if (!stbi_write_bmp_to_func(WriteToMemory_stbi, &data, image->width,
                                image->height, image->component,
                                &image->image[0])) {
      return false;
    }
    header = "data:image/bmp;base64,";
  } else if (!embedImages) {
    // Error: can't output requested format to file
    return false;
  }

  if (embedImages) {
    // Embed base64-encoded image into URI
    if (data.size()) {
      image->uri =
          header +
          base64_encode(&data[0], static_cast<unsigned int>(data.size()));
    } else {
      // Throw error?
    }
  } else {
    // Write image to disc
    FsCallbacks *fs = reinterpret_cast<FsCallbacks *>(fsPtr);
    if ((fs != nullptr) && (fs->WriteWholeFile != nullptr)) {
      const std::string imagefilepath = JoinPath(*basepath, *filename);
      std::string writeError;
      if (!fs->WriteWholeFile(&writeError, imagefilepath, data,
                              fs->user_data)) {
        // Could not write image file to disc; Throw error ?
        return false;
      }
    } else {
      // Throw error?
    }
    image->uri = *filename;
  }

  return true;
}
#endif

void TinyGLTF::SetFsCallbacks(FsCallbacks callbacks) { fs = callbacks; }

#ifdef _WIN32
static inline std::wstring UTF8ToWchar(const std::string &str) {
  int wstr_size =
      MultiByteToWideChar(CP_UTF8, 0, str.data(), (int)str.size(), nullptr, 0);
  std::wstring wstr(wstr_size, 0);
  MultiByteToWideChar(CP_UTF8, 0, str.data(), (int)str.size(), &wstr[0],
                      (int)wstr.size());
  return wstr;
}

static inline std::string WcharToUTF8(const std::wstring &wstr) {
  int str_size = WideCharToMultiByte(CP_UTF8, 0, wstr.data(), (int)wstr.size(),
                                      nullptr, 0, NULL, NULL);
  std::string str(str_size, 0);
  WideCharToMultiByte(CP_UTF8, 0, wstr.data(), (int)wstr.size(), &str[0],
                      (int)str.size(), NULL, NULL);
  return str;
}
#endif

#ifndef TINYGLTF_NO_FS
// Default implementations of filesystem functions

bool FileExists(const std::string &abs_filename, void *) {
  bool ret;
#ifdef TINYGLTF_ANDROID_LOAD_FROM_ASSETS
  if (asset_manager) {
    AAsset *asset = AAssetManager_open(asset_manager, abs_filename.c_str(),
                                       AASSET_MODE_STREAMING);
    if (!asset) {
      return false;
    }
    AAsset_close(asset);
    ret = true;
  } else {
    return false;
  }
#else
#ifdef _WIN32
#if defined(_MSC_VER) || defined(__GLIBCXX__)
  FILE *fp = nullptr;
  errno_t err = _wfopen_s(&fp, UTF8ToWchar(abs_filename).c_str(), L"rb");
  if (err != 0) {
    return false;
  }
#else
  FILE *fp = nullptr;
  errno_t err = fopen_s(&fp, abs_filename.c_str(), "rb");
  if (err != 0) {
    return false;
  }
#endif

#else
  FILE *fp = fopen(abs_filename.c_str(), "rb");
#endif
  if (fp) {
    ret = true;
    fclose(fp);
  } else {
    ret = false;
  }
#endif

  return ret;
}

std::string ExpandFilePath(const std::string &filepath, void *) {
#ifdef _WIN32
  // Assume input `filepath` is encoded in UTF-8
  std::wstring wfilepath = UTF8ToWchar(filepath);
  DWORD wlen = ExpandEnvironmentStringsW(wfilepath.c_str(), nullptr, 0);
  wchar_t *wstr = new wchar_t[wlen];
  ExpandEnvironmentStringsW(wfilepath.c_str(), wstr, wlen);

  std::wstring ws(wstr);
  delete[] wstr;
  return WcharToUTF8(ws);

#else

#if defined(TARGET_OS_IPHONE) || defined(TARGET_IPHONE_SIMULATOR) || \
    defined(__ANDROID__) || defined(__EMSCRIPTEN__)
  // no expansion
  std::string s = filepath;
#else
  std::string s;
  wordexp_t p;

  if (filepath.empty()) {
    return "";
  }

  // Quote the string to keep any spaces in filepath intact.
  std::string quoted_path = "\"" + filepath + "\"";
  // char** w;
  int ret = wordexp(quoted_path.c_str(), &p, 0);
  if (ret) {
    // err
    s = filepath;
    return s;
  }

  // Use first element only.
  if (p.we_wordv) {
    s = std::string(p.we_wordv[0]);
    wordfree(&p);
  } else {
    s = filepath;
  }

#endif

  return s;
#endif
}

bool ReadWholeFile(std::vector<unsigned char> *out, std::string *err,
                   const std::string &filepath, void *) {
#ifdef TINYGLTF_ANDROID_LOAD_FROM_ASSETS
  if (asset_manager) {
    AAsset *asset = AAssetManager_open(asset_manager, filepath.c_str(),
                                       AASSET_MODE_STREAMING);
    if (!asset) {
      if (err) {
        (*err) += "File open error : " + filepath + "\n";
      }
      return false;
    }
    size_t size = AAsset_getLength(asset);
    if (size == 0) {
      if (err) {
        (*err) += "Invalid file size : " + filepath +
                  " (does the path point to a directory?)";
      }
      return false;
    }
    out->resize(size);
    AAsset_read(asset, reinterpret_cast<char *>(&out->at(0)), size);
    AAsset_close(asset);
    return true;
  } else {
    if (err) {
      (*err) += "No asset manager specified : " + filepath + "\n";
    }
    return false;
  }
#else
#ifdef _WIN32
#if defined(__GLIBCXX__)  // mingw
  int file_descriptor =
      _wopen(UTF8ToWchar(filepath).c_str(), _O_RDONLY | _O_BINARY);
  __gnu_cxx::stdio_filebuf<char> wfile_buf(file_descriptor, std::ios_base::in);
  std::istream f(&wfile_buf);
#elif defined(_MSC_VER) || defined(_LIBCPP_VERSION)
  // For libcxx, assume _LIBCPP_HAS_OPEN_WITH_WCHAR is defined to accept `wchar_t *`
  std::ifstream f(UTF8ToWchar(filepath).c_str(), std::ifstream::binary);
#else
  // Unknown compiler/runtime
  std::ifstream f(filepath.c_str(), std::ifstream::binary);
#endif
#else
  std::ifstream f(filepath.c_str(), std::ifstream::binary);
#endif
  if (!f) {
    if (err) {
      (*err) += "File open error : " + filepath + "\n";
    }
    return false;
  }

  f.seekg(0, f.end);
  size_t sz = static_cast<size_t>(f.tellg());
  f.seekg(0, f.beg);

  if (int64_t(sz) < 0) {
    if (err) {
      (*err) += "Invalid file size : " + filepath +
                " (does the path point to a directory?)";
    }
    return false;
  } else if (sz == 0) {
    if (err) {
      (*err) += "File is empty : " + filepath + "\n";
    }
    return false;
  }

  out->resize(sz);
  f.read(reinterpret_cast<char *>(&out->at(0)),
         static_cast<std::streamsize>(sz));

  return true;
#endif
}

bool WriteWholeFile(std::string *err, const std::string &filepath,
                    const std::vector<unsigned char> &contents, void *) {
#ifdef _WIN32
#if defined(__GLIBCXX__)  // mingw
  int file_descriptor = _wopen(UTF8ToWchar(filepath).c_str(),
                               _O_CREAT | _O_WRONLY | _O_TRUNC | _O_BINARY);
  __gnu_cxx::stdio_filebuf<char> wfile_buf(
      file_descriptor, std::ios_base::out | std::ios_base::binary);
  std::ostream f(&wfile_buf);
#elif defined(_MSC_VER)
  std::ofstream f(UTF8ToWchar(filepath).c_str(), std::ofstream::binary);
#else  // clang?
  std::ofstream f(filepath.c_str(), std::ofstream::binary);
#endif
#else
  std::ofstream f(filepath.c_str(), std::ofstream::binary);
#endif
  if (!f) {
    if (err) {
      (*err) += "File open error for writing : " + filepath + "\n";
    }
    return false;
  }

  f.write(reinterpret_cast<const char *>(&contents.at(0)),
          static_cast<std::streamsize>(contents.size()));
  if (!f) {
    if (err) {
      (*err) += "File write error: " + filepath + "\n";
    }
    return false;
  }

  return true;
}

#endif  // TINYGLTF_NO_FS

static std::string MimeToExt(const std::string &mimeType) {
  if (mimeType == "image/jpeg") {
    return "jpg";
  } else if (mimeType == "image/png") {
    return "png";
  } else if (mimeType == "image/bmp") {
    return "bmp";
  } else if (mimeType == "image/gif") {
    return "gif";
  }

  return "";
}

static void UpdateImageObject(Image &image, std::string &baseDir, int index,
                              bool embedImages,
                              WriteImageDataFunction *WriteImageData = nullptr,
                              void *user_data = nullptr) {
  std::string filename;
  std::string ext;
  // If image has uri, use it it as a filename
  if (image.uri.size()) {
    filename = GetBaseFilename(image.uri);
    ext = GetFilePathExtension(filename);
  } else if (image.bufferView != -1) {
    // If there's no URI and the data exists in a buffer,
    // don't change properties or write images
  } else if (image.name.size()) {
    ext = MimeToExt(image.mimeType);
    // Otherwise use name as filename
    filename = image.name + "." + ext;
  } else {
    ext = MimeToExt(image.mimeType);
    // Fallback to index of image as filename
    filename = std::to_string(index) + "." + ext;
  }

  // If callback is set, modify image data object
  if (*WriteImageData != nullptr && !filename.empty()) {
    std::string uri;
    (*WriteImageData)(&baseDir, &filename, &image, embedImages, user_data);
  }
}

bool IsDataURI(const std::string &in) {
  std::string header = "data:application/octet-stream;base64,";
  if (in.find(header) == 0) {
    return true;
  }

  header = "data:image/jpeg;base64,";
  if (in.find(header) == 0) {
    return true;
  }

  header = "data:image/png;base64,";
  if (in.find(header) == 0) {
    return true;
  }

  header = "data:image/bmp;base64,";
  if (in.find(header) == 0) {
    return true;
  }

  header = "data:image/gif;base64,";
  if (in.find(header) == 0) {
    return true;
  }

  header = "data:text/plain;base64,";
  if (in.find(header) == 0) {
    return true;
  }

  header = "data:application/gltf-buffer;base64,";
  if (in.find(header) == 0) {
    return true;
  }

  return false;
}

bool DecodeDataURI(std::vector<unsigned char> *out, std::string &mime_type,
                   const std::string &in, size_t reqBytes, bool checkSize) {
  std::string header = "data:application/octet-stream;base64,";
  std::string data;
  if (in.find(header) == 0) {
    data = base64_decode(in.substr(header.size()));  // cut mime string.
  }

  if (data.empty()) {
    header = "data:image/jpeg;base64,";
    if (in.find(header) == 0) {
      mime_type = "image/jpeg";
      data = base64_decode(in.substr(header.size()));  // cut mime string.
    }
  }

  if (data.empty()) {
    header = "data:image/png;base64,";
    if (in.find(header) == 0) {
      mime_type = "image/png";
      data = base64_decode(in.substr(header.size()));  // cut mime string.
    }
  }

  if (data.empty()) {
    header = "data:image/bmp;base64,";
    if (in.find(header) == 0) {
      mime_type = "image/bmp";
      data = base64_decode(in.substr(header.size()));  // cut mime string.
    }
  }

  if (data.empty()) {
    header = "data:image/gif;base64,";
    if (in.find(header) == 0) {
      mime_type = "image/gif";
      data = base64_decode(in.substr(header.size()));  // cut mime string.
    }
  }

  if (data.empty()) {
    header = "data:text/plain;base64,";
    if (in.find(header) == 0) {
      mime_type = "text/plain";
      data = base64_decode(in.substr(header.size()));
    }
  }

  if (data.empty()) {
    header = "data:application/gltf-buffer;base64,";
    if (in.find(header) == 0) {
      data = base64_decode(in.substr(header.size()));
    }
  }

  // TODO(syoyo): Allow empty buffer? #229
  if (data.empty()) {
    return false;
  }

  if (checkSize) {
    if (data.size() != reqBytes) {
      return false;
    }
    out->resize(reqBytes);
  } else {
    out->resize(data.size());
  }
  std::copy(data.begin(), data.end(), out->begin());
  return true;
}

namespace {
bool GetInt(const json &o, int &val) {
#ifdef TINYGLTF_USE_RAPIDJSON
  if (!o.IsDouble()) {
    if (o.IsInt()) {
      val = o.GetInt();
      return true;
    } else if (o.IsUint()) {
      val = static_cast<int>(o.GetUint());
      return true;
    } else if (o.IsInt64()) {
      val = static_cast<int>(o.GetInt64());
      return true;
    } else if (o.IsUint64()) {
      val = static_cast<int>(o.GetUint64());
      return true;
    }
  }

  return false;
#else
  auto type = o.type();

  if ((type == json::value_t::number_integer) ||
      (type == json::value_t::number_unsigned)) {
    val = static_cast<int>(o.get<int64_t>());
    return true;
  }

  return false;
#endif
}

#ifdef TINYGLTF_USE_RAPIDJSON
bool GetDouble(const json &o, double &val) {
  if (o.IsDouble()) {
    val = o.GetDouble();
    return true;
  }

  return false;
}
#endif

bool GetNumber(const json &o, double &val) {
#ifdef TINYGLTF_USE_RAPIDJSON
  if (o.IsNumber()) {
    val = o.GetDouble();
    return true;
  }

  return false;
#else
  if (o.is_number()) {
    val = o.get<double>();
    return true;
  }

  return false;
#endif
}

bool GetString(const json &o, std::string &val) {
#ifdef TINYGLTF_USE_RAPIDJSON
  if (o.IsString()) {
    val = o.GetString();
    return true;
  }

  return false;
#else
  if (o.type() == json::value_t::string) {
    val = o.get<std::string>();
    return true;
  }

  return false;
#endif
}

bool IsArray(const json &o) {
#ifdef TINYGLTF_USE_RAPIDJSON
  return o.IsArray();
#else
  return o.is_array();
#endif
}

json_const_array_iterator ArrayBegin(const json &o) {
#ifdef TINYGLTF_USE_RAPIDJSON
  return o.Begin();
#else
  return o.begin();
#endif
}

json_const_array_iterator ArrayEnd(const json &o) {
#ifdef TINYGLTF_USE_RAPIDJSON
  return o.End();
#else
  return o.end();
#endif
}

bool IsObject(const json &o) {
#ifdef TINYGLTF_USE_RAPIDJSON
  return o.IsObject();
#else
  return o.is_object();
#endif
}

json_const_iterator ObjectBegin(const json &o) {
#ifdef TINYGLTF_USE_RAPIDJSON
  return o.MemberBegin();
#else
  return o.begin();
#endif
}

json_const_iterator ObjectEnd(const json &o) {
#ifdef TINYGLTF_USE_RAPIDJSON
  return o.MemberEnd();
#else
  return o.end();
#endif
}

const char *GetKey(json_const_iterator &it) {
#ifdef TINYGLTF_USE_RAPIDJSON
  return it->name.GetString();
#else
  return it.key().c_str();
#endif
}

bool FindMember(const json &o, const char *member, json_const_iterator &it) {
#ifdef TINYGLTF_USE_RAPIDJSON
  if (!o.IsObject()) {
    return false;
  }
  it = o.FindMember(member);
  return it != o.MemberEnd();
#else
  it = o.find(member);
  return it != o.end();
#endif
}

const json &GetValue(json_const_iterator &it) {
#ifdef TINYGLTF_USE_RAPIDJSON
  return it->value;
#else
  return it.value();
#endif
}

std::string JsonToString(const json &o, int spacing = -1) {
#ifdef TINYGLTF_USE_RAPIDJSON
  using namespace rapidjson;
  StringBuffer buffer;
  if (spacing == -1) {
    Writer<StringBuffer> writer(buffer);
    o.Accept(writer);
  } else {
    PrettyWriter<StringBuffer> writer(buffer);
    writer.SetIndent(' ', uint32_t(spacing));
    o.Accept(writer);
  }
  return buffer.GetString();
#else
  return o.dump(spacing);
#endif
}

}  // namespace

static bool ParseJsonAsValue(Value *ret, const json &o) {
  Value val{};
#ifdef TINYGLTF_USE_RAPIDJSON
  using rapidjson::Type;
  switch (o.GetType()) {
    case Type::kObjectType: {
      Value::Object value_object;
      for (auto it = o.MemberBegin(); it != o.MemberEnd(); ++it) {
        Value entry;
        ParseJsonAsValue(&entry, it->value);
        if (entry.Type() != NULL_TYPE)
          value_object.emplace(GetKey(it), std::move(entry));
      }
      if (value_object.size() > 0) val = Value(std::move(value_object));
    } break;
    case Type::kArrayType: {
      Value::Array value_array;
      value_array.reserve(o.Size());
      for (auto it = o.Begin(); it != o.End(); ++it) {
        Value entry;
        ParseJsonAsValue(&entry, *it);
        if (entry.Type() != NULL_TYPE)
          value_array.emplace_back(std::move(entry));
      }
      if (value_array.size() > 0) val = Value(std::move(value_array));
    } break;
    case Type::kStringType:
      val = Value(std::string(o.GetString()));
      break;
    case Type::kFalseType:
    case Type::kTrueType:
      val = Value(o.GetBool());
      break;
    case Type::kNumberType:
      if (!o.IsDouble()) {
        int i = 0;
        GetInt(o, i);
        val = Value(i);
      } else {
        double d = 0.0;
        GetDouble(o, d);
        val = Value(d);
      }
      break;
    case Type::kNullType:
      break;
      // all types are covered, so no `case default`
  }
#else
  switch (o.type()) {
    case json::value_t::object: {
      Value::Object value_object;
      for (auto it = o.begin(); it != o.end(); it++) {
        Value entry;
        ParseJsonAsValue(&entry, it.value());
        if (entry.Type() != NULL_TYPE)
          value_object.emplace(it.key(), std::move(entry));
      }
      if (value_object.size() > 0) val = Value(std::move(value_object));
    } break;
    case json::value_t::array: {
      Value::Array value_array;
      value_array.reserve(o.size());
      for (auto it = o.begin(); it != o.end(); it++) {
        Value entry;
        ParseJsonAsValue(&entry, it.value());
        if (entry.Type() != NULL_TYPE)
          value_array.emplace_back(std::move(entry));
      }
      if (value_array.size() > 0) val = Value(std::move(value_array));
    } break;
    case json::value_t::string:
      val = Value(o.get<std::string>());
      break;
    case json::value_t::boolean:
      val = Value(o.get<bool>());
      break;
    case json::value_t::number_integer:
    case json::value_t::number_unsigned:
      val = Value(static_cast<int>(o.get<int64_t>()));
      break;
    case json::value_t::number_float:
      val = Value(o.get<double>());
      break;
    case json::value_t::null:
    case json::value_t::discarded:
      // default:
      break;
  }
#endif
  if (ret) *ret = std::move(val);

  return val.Type() != NULL_TYPE;
}

static bool ParseExtrasProperty(Value *ret, const json &o) {
  json_const_iterator it;
  if (!FindMember(o, "extras", it)) {
    return false;
  }

  return ParseJsonAsValue(ret, GetValue(it));
}

static bool ParseBooleanProperty(bool *ret, std::string *err, const json &o,
                                 const std::string &property,
                                 const bool required,
                                 const std::string &parent_node = "") {
  json_const_iterator it;
  if (!FindMember(o, property.c_str(), it)) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is missing";
        if (!parent_node.empty()) {
          (*err) += " in " + parent_node;
        }
        (*err) += ".\n";
      }
    }
    return false;
  }

  auto &value = GetValue(it);

  bool isBoolean;
  bool boolValue = false;
#ifdef TINYGLTF_USE_RAPIDJSON
  isBoolean = value.IsBool();
  if (isBoolean) {
    boolValue = value.GetBool();
  }
#else
  isBoolean = value.is_boolean();
  if (isBoolean) {
    boolValue = value.get<bool>();
  }
#endif
  if (!isBoolean) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is not a bool type.\n";
      }
    }
    return false;
  }

  if (ret) {
    (*ret) = boolValue;
  }

  return true;
}

static bool ParseIntegerProperty(int *ret, std::string *err, const json &o,
                                 const std::string &property,
                                 const bool required,
                                 const std::string &parent_node = "") {
  json_const_iterator it;
  if (!FindMember(o, property.c_str(), it)) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is missing";
        if (!parent_node.empty()) {
          (*err) += " in " + parent_node;
        }
        (*err) += ".\n";
      }
    }
    return false;
  }

  int intValue;
  bool isInt = GetInt(GetValue(it), intValue);
  if (!isInt) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is not an integer type.\n";
      }
    }
    return false;
  }

  if (ret) {
    (*ret) = intValue;
  }

  return true;
}

static bool ParseUnsignedProperty(size_t *ret, std::string *err, const json &o,
                                  const std::string &property,
                                  const bool required,
                                  const std::string &parent_node = "") {
  json_const_iterator it;
  if (!FindMember(o, property.c_str(), it)) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is missing";
        if (!parent_node.empty()) {
          (*err) += " in " + parent_node;
        }
        (*err) += ".\n";
      }
    }
    return false;
  }

  auto &value = GetValue(it);

  size_t uValue = 0;
  bool isUValue;
#ifdef TINYGLTF_USE_RAPIDJSON
  isUValue = false;
  if (value.IsUint()) {
    uValue = value.GetUint();
    isUValue = true;
  } else if (value.IsUint64()) {
    uValue = value.GetUint64();
    isUValue = true;
  }
#else
  isUValue = value.is_number_unsigned();
  if (isUValue) {
    uValue = value.get<size_t>();
  }
#endif
  if (!isUValue) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is not a positive integer.\n";
      }
    }
    return false;
  }

  if (ret) {
    (*ret) = uValue;
  }

  return true;
}

static bool ParseNumberProperty(double *ret, std::string *err, const json &o,
                                const std::string &property,
                                const bool required,
                                const std::string &parent_node = "") {
  json_const_iterator it;

  if (!FindMember(o, property.c_str(), it)) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is missing";
        if (!parent_node.empty()) {
          (*err) += " in " + parent_node;
        }
        (*err) += ".\n";
      }
    }
    return false;
  }

  double numberValue;
  bool isNumber = GetNumber(GetValue(it), numberValue);

  if (!isNumber) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is not a number type.\n";
      }
    }
    return false;
  }

  if (ret) {
    (*ret) = numberValue;
  }

  return true;
}

static bool ParseNumberArrayProperty(std::vector<double> *ret, std::string *err,
                                     const json &o, const std::string &property,
                                     bool required,
                                     const std::string &parent_node = "") {
  json_const_iterator it;
  if (!FindMember(o, property.c_str(), it)) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is missing";
        if (!parent_node.empty()) {
          (*err) += " in " + parent_node;
        }
        (*err) += ".\n";
      }
    }
    return false;
  }

  if (!IsArray(GetValue(it))) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is not an array";
        if (!parent_node.empty()) {
          (*err) += " in " + parent_node;
        }
        (*err) += ".\n";
      }
    }
    return false;
  }

  ret->clear();
  auto end = ArrayEnd(GetValue(it));
  for (auto i = ArrayBegin(GetValue(it)); i != end; ++i) {
    double numberValue;
    const bool isNumber = GetNumber(*i, numberValue);
    if (!isNumber) {
      if (required) {
        if (err) {
          (*err) += "'" + property + "' property is not a number.\n";
          if (!parent_node.empty()) {
            (*err) += " in " + parent_node;
          }
          (*err) += ".\n";
        }
      }
      return false;
    }
    ret->push_back(numberValue);
  }

  return true;
}

static bool ParseIntegerArrayProperty(std::vector<int> *ret, std::string *err,
                                      const json &o,
                                      const std::string &property,
                                      bool required,
                                      const std::string &parent_node = "") {
  json_const_iterator it;
  if (!FindMember(o, property.c_str(), it)) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is missing";
        if (!parent_node.empty()) {
          (*err) += " in " + parent_node;
        }
        (*err) += ".\n";
      }
    }
    return false;
  }

  if (!IsArray(GetValue(it))) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is not an array";
        if (!parent_node.empty()) {
          (*err) += " in " + parent_node;
        }
        (*err) += ".\n";
      }
    }
    return false;
  }

  ret->clear();
  auto end = ArrayEnd(GetValue(it));
  for (auto i = ArrayBegin(GetValue(it)); i != end; ++i) {
    int numberValue;
    bool isNumber = GetInt(*i, numberValue);
    if (!isNumber) {
      if (required) {
        if (err) {
          (*err) += "'" + property + "' property is not an integer type.\n";
          if (!parent_node.empty()) {
            (*err) += " in " + parent_node;
          }
          (*err) += ".\n";
        }
      }
      return false;
    }
    ret->push_back(numberValue);
  }

  return true;
}

static bool ParseStringProperty(
    std::string *ret, std::string *err, const json &o,
    const std::string &property, bool required,
    const std::string &parent_node = std::string()) {
  json_const_iterator it;
  if (!FindMember(o, property.c_str(), it)) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is missing";
        if (parent_node.empty()) {
          (*err) += ".\n";
        } else {
          (*err) += " in `" + parent_node + "'.\n";
        }
      }
    }
    return false;
  }

  std::string strValue;
  if (!GetString(GetValue(it), strValue)) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is not a string type.\n";
      }
    }
    return false;
  }

  if (ret) {
    (*ret) = std::move(strValue);
  }

  return true;
}

static bool ParseStringIntegerProperty(std::map<std::string, int> *ret,
                                       std::string *err, const json &o,
                                       const std::string &property,
                                       bool required,
                                       const std::string &parent = "") {
  json_const_iterator it;
  if (!FindMember(o, property.c_str(), it)) {
    if (required) {
      if (err) {
        if (!parent.empty()) {
          (*err) +=
              "'" + property + "' property is missing in " + parent + ".\n";
        } else {
          (*err) += "'" + property + "' property is missing.\n";
        }
      }
    }
    return false;
  }

  const json &dict = GetValue(it);

  // Make sure we are dealing with an object / dictionary.
  if (!IsObject(dict)) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is not an object.\n";
      }
    }
    return false;
  }

  ret->clear();

  json_const_iterator dictIt(ObjectBegin(dict));
  json_const_iterator dictItEnd(ObjectEnd(dict));

  for (; dictIt != dictItEnd; ++dictIt) {
    int intVal;
    if (!GetInt(GetValue(dictIt), intVal)) {
      if (required) {
        if (err) {
          (*err) += "'" + property + "' value is not an integer type.\n";
        }
      }
      return false;
    }

    // Insert into the list.
    (*ret)[GetKey(dictIt)] = intVal;
  }
  return true;
}

static bool ParseJSONProperty(std::map<std::string, double> *ret,
                              std::string *err, const json &o,
                              const std::string &property, bool required) {
  json_const_iterator it;
  if (!FindMember(o, property.c_str(), it)) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is missing. \n'";
      }
    }
    return false;
  }

  const json &obj = GetValue(it);

  if (!IsObject(obj)) {
    if (required) {
      if (err) {
        (*err) += "'" + property + "' property is not a JSON object.\n";
      }
    }
    return false;
  }

  ret->clear();

  json_const_iterator it2(ObjectBegin(obj));
  json_const_iterator itEnd(ObjectEnd(obj));
  for (; it2 != itEnd; ++it2) {
    double numVal;
    if (GetNumber(GetValue(it2), numVal))
      ret->emplace(std::string(GetKey(it2)), numVal);
  }

  return true;
}

static bool ParseParameterProperty(Parameter *param, std::string *err,
                                   const json &o, const std::string &prop,
                                   bool required) {
  // A parameter value can either be a string or an array of either a boolean or
  // a number. Booleans of any kind aren't supported here. Granted, it
  // complicates the Parameter structure and breaks it semantically in the sense
  // that the client probably works off the assumption that if the string is
  // empty the vector is used, etc. Would a tagged union work?
  if (ParseStringProperty(&param->string_value, err, o, prop, false)) {
    // Found string property.
    return true;
  } else if (ParseNumberArrayProperty(&param->number_array, err, o, prop,
                                      false)) {
    // Found a number array.
    return true;
  } else if (ParseNumberProperty(&param->number_value, err, o, prop, false)) {
    return param->has_number_value = true;
  } else if (ParseJSONProperty(&param->json_double_value, err, o, prop,
                               false)) {
    return true;
  } else if (ParseBooleanProperty(&param->bool_value, err, o, prop, false)) {
    return true;
  } else {
    if (required) {
      if (err) {
        (*err) += "parameter must be a string or number / number array.\n";
      }
    }
    return false;
  }
}

static bool ParseExtensionsProperty(ExtensionMap *ret, std::string *err,
                                    const json &o) {
  (void)err;

  json_const_iterator it;
  if (!FindMember(o, "extensions", it)) {
    return false;
  }

  auto &obj = GetValue(it);
  if (!IsObject(obj)) {
    return false;
  }
  ExtensionMap extensions;
  json_const_iterator extIt = ObjectBegin(obj);  // it.value().begin();
  json_const_iterator extEnd = ObjectEnd(obj);
  for (; extIt != extEnd; ++extIt) {
    auto &itObj = GetValue(extIt);
    if (!IsObject(itObj)) continue;
    std::string key(GetKey(extIt));
    if (!ParseJsonAsValue(&extensions[key], itObj)) {
      if (!key.empty()) {
        // create empty object so that an extension object is still of type
        // object
        extensions[key] = Value{Value::Object{}};
      }
    }
  }
  if (ret) {
    (*ret) = std::move(extensions);
  }
  return true;
}

static bool ParseAsset(Asset *asset, std::string *err, const json &o,
                       bool store_original_json_for_extras_and_extensions) {
  ParseStringProperty(&asset->version, err, o, "version", true, "Asset");
  ParseStringProperty(&asset->generator, err, o, "generator", false, "Asset");
  ParseStringProperty(&asset->minVersion, err, o, "minVersion", false, "Asset");
  ParseStringProperty(&asset->copyright, err, o, "copyright", false, "Asset");

  ParseExtensionsProperty(&asset->extensions, err, o);

  // Unity exporter version is added as extra here
  ParseExtrasProperty(&(asset->extras), o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        asset->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        asset->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  return true;
}

static bool ParseImage(Image *image, const int image_idx, std::string *err,
                       std::string *warn, const json &o,
                       bool store_original_json_for_extras_and_extensions,
                       const std::string &basedir, FsCallbacks *fs,
                       LoadImageDataFunction *LoadImageData = nullptr,
                       void *load_image_user_data = nullptr) {
  // A glTF image must either reference a bufferView or an image uri

  // schema says oneOf [`bufferView`, `uri`]
  // TODO(syoyo): Check the type of each parameters.
  json_const_iterator it;
  bool hasBufferView = FindMember(o, "bufferView", it);
  bool hasURI = FindMember(o, "uri", it);

  ParseStringProperty(&image->name, err, o, "name", false);

  if (hasBufferView && hasURI) {
    // Should not both defined.
    if (err) {
      (*err) +=
          "Only one of `bufferView` or `uri` should be defined, but both are "
          "defined for image[" +
          std::to_string(image_idx) + "] name = \"" + image->name + "\"\n";
    }
    return false;
  }

  if (!hasBufferView && !hasURI) {
    if (err) {
      (*err) += "Neither required `bufferView` nor `uri` defined for image[" +
                std::to_string(image_idx) + "] name = \"" + image->name +
                "\"\n";
    }
    return false;
  }

  ParseExtensionsProperty(&image->extensions, err, o);
  ParseExtrasProperty(&image->extras, o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator eit;
      if (FindMember(o, "extensions", eit)) {
        image->extensions_json_string = JsonToString(GetValue(eit));
      }
    }
    {
      json_const_iterator eit;
      if (FindMember(o, "extras", eit)) {
        image->extras_json_string = JsonToString(GetValue(eit));
      }
    }
  }

  if (hasBufferView) {
    int bufferView = -1;
    if (!ParseIntegerProperty(&bufferView, err, o, "bufferView", true)) {
      if (err) {
        (*err) += "Failed to parse `bufferView` for image[" +
                  std::to_string(image_idx) + "] name = \"" + image->name +
                  "\"\n";
      }
      return false;
    }

    std::string mime_type;
    ParseStringProperty(&mime_type, err, o, "mimeType", false);

    int width = 0;
    ParseIntegerProperty(&width, err, o, "width", false);

    int height = 0;
    ParseIntegerProperty(&height, err, o, "height", false);

    // Just only save some information here. Loading actual image data from
    // bufferView is done after this `ParseImage` function.
    image->bufferView = bufferView;
    image->mimeType = mime_type;
    image->width = width;
    image->height = height;

    return true;
  }

  // Parse URI & Load image data.

  std::string uri;
  std::string tmp_err;
  if (!ParseStringProperty(&uri, &tmp_err, o, "uri", true)) {
    if (err) {
      (*err) += "Failed to parse `uri` for image[" + std::to_string(image_idx) +
                "] name = \"" + image->name + "\".\n";
    }
    return false;
  }

  std::vector<unsigned char> img;

  if (IsDataURI(uri)) {
    if (!DecodeDataURI(&img, image->mimeType, uri, 0, false)) {
      if (err) {
        (*err) += "Failed to decode 'uri' for image[" +
                  std::to_string(image_idx) + "] name = [" + image->name +
                  "]\n";
      }
      return false;
    }
  } else {
    // Assume external file
    // Keep texture path (for textures that cannot be decoded)
    image->uri = uri;
#ifdef TINYGLTF_NO_EXTERNAL_IMAGE
    return true;
#endif
    std::string decoded_uri = dlib::urldecode(uri);
    if (!LoadExternalFile(&img, err, warn, decoded_uri, basedir,
                          /* required */ false, /* required bytes */ 0,
                          /* checksize */ false, fs)) {
      if (warn) {
        (*warn) += "Failed to load external 'uri' for image[" +
                   std::to_string(image_idx) + "] name = [" + image->name +
                   "]\n";
      }
      // If the image cannot be loaded, keep uri as image->uri.
      return true;
    }

    if (img.empty()) {
      if (warn) {
        (*warn) += "Image data is empty for image[" +
                   std::to_string(image_idx) + "] name = [" + image->name +
                   "] \n";
      }
      return false;
    }
  }

  if (*LoadImageData == nullptr) {
    if (err) {
      (*err) += "No LoadImageData callback specified.\n";
    }
    return false;
  }
  return (*LoadImageData)(image, image_idx, err, warn, 0, 0, &img.at(0),
                          static_cast<int>(img.size()), load_image_user_data);
}

static bool ParseTexture(Texture *texture, std::string *err, const json &o,
                         bool store_original_json_for_extras_and_extensions,
                         const std::string &basedir) {
  (void)basedir;
  int sampler = -1;
  int source = -1;
  ParseIntegerProperty(&sampler, err, o, "sampler", false);

  ParseIntegerProperty(&source, err, o, "source", false);

  texture->sampler = sampler;
  texture->source = source;

  ParseExtensionsProperty(&texture->extensions, err, o);
  ParseExtrasProperty(&texture->extras, o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        texture->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        texture->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  ParseStringProperty(&texture->name, err, o, "name", false);

  return true;
}

static bool ParseTextureInfo(
    TextureInfo *texinfo, std::string *err, const json &o,
    bool store_original_json_for_extras_and_extensions) {
  if (texinfo == nullptr) {
    return false;
  }

  if (!ParseIntegerProperty(&texinfo->index, err, o, "index",
                            /* required */ true, "TextureInfo")) {
    return false;
  }

  ParseIntegerProperty(&texinfo->texCoord, err, o, "texCoord", false);

  ParseExtensionsProperty(&texinfo->extensions, err, o);
  ParseExtrasProperty(&texinfo->extras, o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        texinfo->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        texinfo->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  return true;
}

static bool ParseNormalTextureInfo(
    NormalTextureInfo *texinfo, std::string *err, const json &o,
    bool store_original_json_for_extras_and_extensions) {
  if (texinfo == nullptr) {
    return false;
  }

  if (!ParseIntegerProperty(&texinfo->index, err, o, "index",
                            /* required */ true, "NormalTextureInfo")) {
    return false;
  }

  ParseIntegerProperty(&texinfo->texCoord, err, o, "texCoord", false);
  ParseNumberProperty(&texinfo->scale, err, o, "scale", false);

  ParseExtensionsProperty(&texinfo->extensions, err, o);
  ParseExtrasProperty(&texinfo->extras, o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        texinfo->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        texinfo->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  return true;
}

static bool ParseOcclusionTextureInfo(
    OcclusionTextureInfo *texinfo, std::string *err, const json &o,
    bool store_original_json_for_extras_and_extensions) {
  if (texinfo == nullptr) {
    return false;
  }

  if (!ParseIntegerProperty(&texinfo->index, err, o, "index",
                            /* required */ true, "NormalTextureInfo")) {
    return false;
  }

  ParseIntegerProperty(&texinfo->texCoord, err, o, "texCoord", false);
  ParseNumberProperty(&texinfo->strength, err, o, "strength", false);

  ParseExtensionsProperty(&texinfo->extensions, err, o);
  ParseExtrasProperty(&texinfo->extras, o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        texinfo->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        texinfo->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  return true;
}

static bool ParseBuffer(Buffer *buffer, std::string *err, const json &o,
                        bool store_original_json_for_extras_and_extensions,
                        FsCallbacks *fs, const std::string &basedir,
                        bool is_binary = false,
                        const unsigned char *bin_data = nullptr,
                        size_t bin_size = 0) {
  size_t byteLength;
  if (!ParseUnsignedProperty(&byteLength, err, o, "byteLength", true,
                             "Buffer")) {
    return false;
  }

  // In glTF 2.0, uri is not mandatory anymore
  buffer->uri.clear();
  ParseStringProperty(&buffer->uri, err, o, "uri", false, "Buffer");

  // having an empty uri for a non embedded image should not be valid
  if (!is_binary && buffer->uri.empty()) {
    if (err) {
      (*err) += "'uri' is missing from non binary glTF file buffer.\n";
    }
  }

  json_const_iterator type;
  if (FindMember(o, "type", type)) {
    std::string typeStr;
    if (GetString(GetValue(type), typeStr)) {
      if (typeStr.compare("arraybuffer") == 0) {
        // buffer.type = "arraybuffer";
      }
    }
  }

  if (is_binary) {
    // Still binary glTF accepts external dataURI.
    if (!buffer->uri.empty()) {
      // First try embedded data URI.
      if (IsDataURI(buffer->uri)) {
        std::string mime_type;
        if (!DecodeDataURI(&buffer->data, mime_type, buffer->uri, byteLength,
                           true)) {
          if (err) {
            (*err) +=
                "Failed to decode 'uri' : " + buffer->uri + " in Buffer\n";
          }
          return false;
        }
      } else {
        // External .bin file.
        std::string decoded_uri = dlib::urldecode(buffer->uri);
        if (!LoadExternalFile(&buffer->data, err, /* warn */ nullptr,
                              decoded_uri, basedir, /* required */ true,
                              byteLength, /* checkSize */ true, fs)) {
          return false;
        }
      }
    } else {
      // load data from (embedded) binary data

      if ((bin_size == 0) || (bin_data == nullptr)) {
        if (err) {
          (*err) += "Invalid binary data in `Buffer'.\n";
        }
        return false;
      }

      if (byteLength > bin_size) {
        if (err) {
          std::stringstream ss;
          ss << "Invalid `byteLength'. Must be equal or less than binary size: "
                "`byteLength' = "
             << byteLength << ", binary size = " << bin_size << std::endl;
          (*err) += ss.str();
        }
        return false;
      }

      // Read buffer data
      buffer->data.resize(static_cast<size_t>(byteLength));
      memcpy(&(buffer->data.at(0)), bin_data, static_cast<size_t>(byteLength));
    }

  } else {
    if (IsDataURI(buffer->uri)) {
      std::string mime_type;
      if (!DecodeDataURI(&buffer->data, mime_type, buffer->uri, byteLength,
                         true)) {
        if (err) {
          (*err) += "Failed to decode 'uri' : " + buffer->uri + " in Buffer\n";
        }
        return false;
      }
    } else {
      // Assume external .bin file.
      std::string decoded_uri = dlib::urldecode(buffer->uri);
      if (!LoadExternalFile(&buffer->data, err, /* warn */ nullptr, decoded_uri,
                            basedir, /* required */ true, byteLength,
                            /* checkSize */ true, fs)) {
        return false;
      }
    }
  }

  ParseStringProperty(&buffer->name, err, o, "name", false);

  ParseExtensionsProperty(&buffer->extensions, err, o);
  ParseExtrasProperty(&buffer->extras, o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        buffer->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        buffer->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  return true;
}

static bool ParseBufferView(
    BufferView *bufferView, std::string *err, const json &o,
    bool store_original_json_for_extras_and_extensions) {
  int buffer = -1;
  if (!ParseIntegerProperty(&buffer, err, o, "buffer", true, "BufferView")) {
    return false;
  }

  size_t byteOffset = 0;
  ParseUnsignedProperty(&byteOffset, err, o, "byteOffset", false);

  size_t byteLength = 1;
  if (!ParseUnsignedProperty(&byteLength, err, o, "byteLength", true,
                             "BufferView")) {
    return false;
  }

  size_t byteStride = 0;
  if (!ParseUnsignedProperty(&byteStride, err, o, "byteStride", false)) {
    // Spec says: When byteStride of referenced bufferView is not defined, it
    // means that accessor elements are tightly packed, i.e., effective stride
    // equals the size of the element.
    // We cannot determine the actual byteStride until Accessor are parsed, thus
    // set 0(= tightly packed) here(as done in OpenGL's VertexAttribPoiner)
    byteStride = 0;
  }

  if ((byteStride > 252) || ((byteStride % 4) != 0)) {
    if (err) {
      std::stringstream ss;
      ss << "Invalid `byteStride' value. `byteStride' must be the multiple of "
            "4 : "
         << byteStride << std::endl;

      (*err) += ss.str();
    }
    return false;
  }

  int target = 0;
  ParseIntegerProperty(&target, err, o, "target", false);
  if ((target == TINYGLTF_TARGET_ARRAY_BUFFER) ||
      (target == TINYGLTF_TARGET_ELEMENT_ARRAY_BUFFER)) {
    // OK
  } else {
    target = 0;
  }
  bufferView->target = target;

  ParseStringProperty(&bufferView->name, err, o, "name", false);

  ParseExtensionsProperty(&bufferView->extensions, err, o);
  ParseExtrasProperty(&bufferView->extras, o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        bufferView->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        bufferView->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  bufferView->buffer = buffer;
  bufferView->byteOffset = byteOffset;
  bufferView->byteLength = byteLength;
  bufferView->byteStride = byteStride;
  return true;
}

static bool ParseSparseAccessor(Accessor *accessor, std::string *err,
                                const json &o) {
  accessor->sparse.isSparse = true;

  int count = 0;
  ParseIntegerProperty(&count, err, o, "count", true);

  json_const_iterator indices_iterator;
  json_const_iterator values_iterator;
  if (!FindMember(o, "indices", indices_iterator)) {
    (*err) = "the sparse object of this accessor doesn't have indices";
    return false;
  }

  if (!FindMember(o, "values", values_iterator)) {
    (*err) = "the sparse object ob ths accessor doesn't have values";
    return false;
  }

  const json &indices_obj = GetValue(indices_iterator);
  const json &values_obj = GetValue(values_iterator);

  int indices_buffer_view = 0, indices_byte_offset = 0, component_type = 0;
  ParseIntegerProperty(&indices_buffer_view, err, indices_obj, "bufferView",
                       true);
  ParseIntegerProperty(&indices_byte_offset, err, indices_obj, "byteOffset",
                       true);
  ParseIntegerProperty(&component_type, err, indices_obj, "componentType",
                       true);

  int values_buffer_view = 0, values_byte_offset = 0;
  ParseIntegerProperty(&values_buffer_view, err, values_obj, "bufferView",
                       true);
  ParseIntegerProperty(&values_byte_offset, err, values_obj, "byteOffset",
                       true);

  accessor->sparse.count = count;
  accessor->sparse.indices.bufferView = indices_buffer_view;
  accessor->sparse.indices.byteOffset = indices_byte_offset;
  accessor->sparse.indices.componentType = component_type;
  accessor->sparse.values.bufferView = values_buffer_view;
  accessor->sparse.values.byteOffset = values_byte_offset;

  // todo check theses values

  return true;
}

static bool ParseAccessor(Accessor *accessor, std::string *err, const json &o,
                          bool store_original_json_for_extras_and_extensions) {
  int bufferView = -1;
  ParseIntegerProperty(&bufferView, err, o, "bufferView", false, "Accessor");

  size_t byteOffset = 0;
  ParseUnsignedProperty(&byteOffset, err, o, "byteOffset", false, "Accessor");

  bool normalized = false;
  ParseBooleanProperty(&normalized, err, o, "normalized", false, "Accessor");

  size_t componentType = 0;
  if (!ParseUnsignedProperty(&componentType, err, o, "componentType", true,
                             "Accessor")) {
    return false;
  }

  size_t count = 0;
  if (!ParseUnsignedProperty(&count, err, o, "count", true, "Accessor")) {
    return false;
  }

  std::string type;
  if (!ParseStringProperty(&type, err, o, "type", true, "Accessor")) {
    return false;
  }

  if (type.compare("SCALAR") == 0) {
    accessor->type = TINYGLTF_TYPE_SCALAR;
  } else if (type.compare("VEC2") == 0) {
    accessor->type = TINYGLTF_TYPE_VEC2;
  } else if (type.compare("VEC3") == 0) {
    accessor->type = TINYGLTF_TYPE_VEC3;
  } else if (type.compare("VEC4") == 0) {
    accessor->type = TINYGLTF_TYPE_VEC4;
  } else if (type.compare("MAT2") == 0) {
    accessor->type = TINYGLTF_TYPE_MAT2;
  } else if (type.compare("MAT3") == 0) {
    accessor->type = TINYGLTF_TYPE_MAT3;
  } else if (type.compare("MAT4") == 0) {
    accessor->type = TINYGLTF_TYPE_MAT4;
  } else {
    std::stringstream ss;
    ss << "Unsupported `type` for accessor object. Got \"" << type << "\"\n";
    if (err) {
      (*err) += ss.str();
    }
    return false;
  }

  ParseStringProperty(&accessor->name, err, o, "name", false);

  accessor->minValues.clear();
  accessor->maxValues.clear();
  ParseNumberArrayProperty(&accessor->minValues, err, o, "min", false,
                           "Accessor");

  ParseNumberArrayProperty(&accessor->maxValues, err, o, "max", false,
                           "Accessor");

  accessor->count = count;
  accessor->bufferView = bufferView;
  accessor->byteOffset = byteOffset;
  accessor->normalized = normalized;
  {
    if (componentType >= TINYGLTF_COMPONENT_TYPE_BYTE &&
        componentType <= TINYGLTF_COMPONENT_TYPE_DOUBLE) {
      // OK
      accessor->componentType = int(componentType);
    } else {
      std::stringstream ss;
      ss << "Invalid `componentType` in accessor. Got " << componentType
         << "\n";
      if (err) {
        (*err) += ss.str();
      }
      return false;
    }
  }

  ParseExtensionsProperty(&(accessor->extensions), err, o);
  ParseExtrasProperty(&(accessor->extras), o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        accessor->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        accessor->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  // check if accessor has a "sparse" object:
  json_const_iterator iterator;
  if (FindMember(o, "sparse", iterator)) {
    // here this accessor has a "sparse" subobject
    return ParseSparseAccessor(accessor, err, GetValue(iterator));
  }

  return true;
}

#ifdef TINYGLTF_ENABLE_DRACO

static void DecodeIndexBuffer(draco::Mesh *mesh, size_t componentSize,
                              std::vector<uint8_t> &outBuffer) {
  if (componentSize == 4) {
    assert(sizeof(mesh->face(draco::FaceIndex(0))[0]) == componentSize);
    memcpy(outBuffer.data(), &mesh->face(draco::FaceIndex(0))[0],
           outBuffer.size());
  } else {
    size_t faceStride = componentSize * 3;
    for (draco::FaceIndex f(0); f < mesh->num_faces(); ++f) {
      const draco::Mesh::Face &face = mesh->face(f);
      if (componentSize == 2) {
        uint16_t indices[3] = {(uint16_t)face[0].value(),
                               (uint16_t)face[1].value(),
                               (uint16_t)face[2].value()};
        memcpy(outBuffer.data() + f.value() * faceStride, &indices[0],
               faceStride);
      } else {
        uint8_t indices[3] = {(uint8_t)face[0].value(),
                              (uint8_t)face[1].value(),
                              (uint8_t)face[2].value()};
        memcpy(outBuffer.data() + f.value() * faceStride, &indices[0],
               faceStride);
      }
    }
  }
}

template <typename T>
static bool GetAttributeForAllPoints(draco::Mesh *mesh,
                                     const draco::PointAttribute *pAttribute,
                                     std::vector<uint8_t> &outBuffer) {
  size_t byteOffset = 0;
  T values[4] = {0, 0, 0, 0};
  for (draco::PointIndex i(0); i < mesh->num_points(); ++i) {
    const draco::AttributeValueIndex val_index = pAttribute->mapped_index(i);
    if (!pAttribute->ConvertValue<T>(val_index, pAttribute->num_components(),
                                     values))
      return false;

    memcpy(outBuffer.data() + byteOffset, &values[0],
           sizeof(T) * pAttribute->num_components());
    byteOffset += sizeof(T) * pAttribute->num_components();
  }

  return true;
}

static bool GetAttributeForAllPoints(uint32_t componentType, draco::Mesh *mesh,
                                     const draco::PointAttribute *pAttribute,
                                     std::vector<uint8_t> &outBuffer) {
  bool decodeResult = false;
  switch (componentType) {
    case TINYGLTF_COMPONENT_TYPE_UNSIGNED_BYTE:
      decodeResult =
          GetAttributeForAllPoints<uint8_t>(mesh, pAttribute, outBuffer);
      break;
    case TINYGLTF_COMPONENT_TYPE_BYTE:
      decodeResult =
          GetAttributeForAllPoints<int8_t>(mesh, pAttribute, outBuffer);
      break;
    case TINYGLTF_COMPONENT_TYPE_UNSIGNED_SHORT:
      decodeResult =
          GetAttributeForAllPoints<uint16_t>(mesh, pAttribute, outBuffer);
      break;
    case TINYGLTF_COMPONENT_TYPE_SHORT:
      decodeResult =
          GetAttributeForAllPoints<int16_t>(mesh, pAttribute, outBuffer);
      break;
    case TINYGLTF_COMPONENT_TYPE_INT:
      decodeResult =
          GetAttributeForAllPoints<int32_t>(mesh, pAttribute, outBuffer);
      break;
    case TINYGLTF_COMPONENT_TYPE_UNSIGNED_INT:
      decodeResult =
          GetAttributeForAllPoints<uint32_t>(mesh, pAttribute, outBuffer);
      break;
    case TINYGLTF_COMPONENT_TYPE_FLOAT:
      decodeResult =
          GetAttributeForAllPoints<float>(mesh, pAttribute, outBuffer);
      break;
    case TINYGLTF_COMPONENT_TYPE_DOUBLE:
      decodeResult =
          GetAttributeForAllPoints<double>(mesh, pAttribute, outBuffer);
      break;
    default:
      return false;
  }

  return decodeResult;
}

static bool ParseDracoExtension(Primitive *primitive, Model *model,
                                std::string *err,
                                const Value &dracoExtensionValue) {
  auto bufferViewValue = dracoExtensionValue.Get("bufferView");
  if (!bufferViewValue.IsInt()) return false;
  auto attributesValue = dracoExtensionValue.Get("attributes");
  if (!attributesValue.IsObject()) return false;

  auto attributesObject = attributesValue.Get<Value::Object>();
  int bufferView = bufferViewValue.Get<int>();

  BufferView &view = model->bufferViews[bufferView];
  Buffer &buffer = model->buffers[view.buffer];
  // BufferView has already been decoded
  if (view.dracoDecoded) return true;
  view.dracoDecoded = true;

  const char *bufferViewData =
      reinterpret_cast<const char *>(buffer.data.data() + view.byteOffset);
  size_t bufferViewSize = view.byteLength;

  // decode draco
  draco::DecoderBuffer decoderBuffer;
  decoderBuffer.Init(bufferViewData, bufferViewSize);
  draco::Decoder decoder;
  auto decodeResult = decoder.DecodeMeshFromBuffer(&decoderBuffer);
  if (!decodeResult.ok()) {
    return false;
  }
  const std::unique_ptr<draco::Mesh> &mesh = decodeResult.value();

  // create new bufferView for indices
  if (primitive->indices >= 0) {
    int32_t componentSize = GetComponentSizeInBytes(
        model->accessors[primitive->indices].componentType);
    Buffer decodedIndexBuffer;
    decodedIndexBuffer.data.resize(mesh->num_faces() * 3 * componentSize);

    DecodeIndexBuffer(mesh.get(), componentSize, decodedIndexBuffer.data);

    model->buffers.emplace_back(std::move(decodedIndexBuffer));

    BufferView decodedIndexBufferView;
    decodedIndexBufferView.buffer = int(model->buffers.size() - 1);
    decodedIndexBufferView.byteLength =
        int(mesh->num_faces() * 3 * componentSize);
    decodedIndexBufferView.byteOffset = 0;
    decodedIndexBufferView.byteStride = 0;
    decodedIndexBufferView.target = TINYGLTF_TARGET_ARRAY_BUFFER;
    model->bufferViews.emplace_back(std::move(decodedIndexBufferView));

    model->accessors[primitive->indices].bufferView =
        int(model->bufferViews.size() - 1);
    model->accessors[primitive->indices].count = int(mesh->num_faces() * 3);
  }

  for (const auto &attribute : attributesObject) {
    if (!attribute.second.IsInt()) return false;
    auto primitiveAttribute = primitive->attributes.find(attribute.first);
    if (primitiveAttribute == primitive->attributes.end()) return false;

    int dracoAttributeIndex = attribute.second.Get<int>();
    const auto pAttribute = mesh->GetAttributeByUniqueId(dracoAttributeIndex);
    const auto pBuffer = pAttribute->buffer();
    const auto componentType =
        model->accessors[primitiveAttribute->second].componentType;

    // Create a new buffer for this decoded buffer
    Buffer decodedBuffer;
    size_t bufferSize = mesh->num_points() * pAttribute->num_components() *
                        GetComponentSizeInBytes(componentType);
    decodedBuffer.data.resize(bufferSize);

    if (!GetAttributeForAllPoints(componentType, mesh.get(), pAttribute,
                                  decodedBuffer.data))
      return false;

    model->buffers.emplace_back(std::move(decodedBuffer));

    BufferView decodedBufferView;
    decodedBufferView.buffer = int(model->buffers.size() - 1);
    decodedBufferView.byteLength = bufferSize;
    decodedBufferView.byteOffset = pAttribute->byte_offset();
    decodedBufferView.byteStride = pAttribute->byte_stride();
    decodedBufferView.target = primitive->indices >= 0
                                   ? TINYGLTF_TARGET_ELEMENT_ARRAY_BUFFER
                                   : TINYGLTF_TARGET_ARRAY_BUFFER;
    model->bufferViews.emplace_back(std::move(decodedBufferView));

    model->accessors[primitiveAttribute->second].bufferView =
        int(model->bufferViews.size() - 1);
    model->accessors[primitiveAttribute->second].count =
        int(mesh->num_points());
  }

  return true;
}
#endif

static bool ParsePrimitive(Primitive *primitive, Model *model, std::string *err,
                           const json &o,
                           bool store_original_json_for_extras_and_extensions) {
  int material = -1;
  ParseIntegerProperty(&material, err, o, "material", false);
  primitive->material = material;

  int mode = TINYGLTF_MODE_TRIANGLES;
  ParseIntegerProperty(&mode, err, o, "mode", false);
  primitive->mode = mode;  // Why only triangled were supported ?

  int indices = -1;
  ParseIntegerProperty(&indices, err, o, "indices", false);
  primitive->indices = indices;
  if (!ParseStringIntegerProperty(&primitive->attributes, err, o, "attributes",
                                  true, "Primitive")) {
    return false;
  }

  // Look for morph targets
  json_const_iterator targetsObject;
  if (FindMember(o, "targets", targetsObject) &&
      IsArray(GetValue(targetsObject))) {
    auto targetsObjectEnd = ArrayEnd(GetValue(targetsObject));
    for (json_const_array_iterator i = ArrayBegin(GetValue(targetsObject));
         i != targetsObjectEnd; ++i) {
      std::map<std::string, int> targetAttribues;

      const json &dict = *i;
      if (IsObject(dict)) {
        json_const_iterator dictIt(ObjectBegin(dict));
        json_const_iterator dictItEnd(ObjectEnd(dict));

        for (; dictIt != dictItEnd; ++dictIt) {
          int iVal;
          if (GetInt(GetValue(dictIt), iVal))
            targetAttribues[GetKey(dictIt)] = iVal;
        }
        primitive->targets.emplace_back(std::move(targetAttribues));
      }
    }
  }

  ParseExtrasProperty(&(primitive->extras), o);
  ParseExtensionsProperty(&primitive->extensions, err, o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        primitive->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        primitive->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

#ifdef TINYGLTF_ENABLE_DRACO
  auto dracoExtension =
      primitive->extensions.find("KHR_draco_mesh_compression");
  if (dracoExtension != primitive->extensions.end()) {
    ParseDracoExtension(primitive, model, err, dracoExtension->second);
  }
#else
  (void)model;
#endif

  return true;
}

static bool ParseMesh(Mesh *mesh, Model *model, std::string *err, const json &o,
                      bool store_original_json_for_extras_and_extensions) {
  ParseStringProperty(&mesh->name, err, o, "name", false);

  mesh->primitives.clear();
  json_const_iterator primObject;
  if (FindMember(o, "primitives", primObject) &&
      IsArray(GetValue(primObject))) {
    json_const_array_iterator primEnd = ArrayEnd(GetValue(primObject));
    for (json_const_array_iterator i = ArrayBegin(GetValue(primObject));
         i != primEnd; ++i) {
      Primitive primitive;
      if (ParsePrimitive(&primitive, model, err, *i,
                         store_original_json_for_extras_and_extensions)) {
        // Only add the primitive if the parsing succeeds.
        mesh->primitives.emplace_back(std::move(primitive));
      }
    }
  }

  // Should probably check if has targets and if dimensions fit
  ParseNumberArrayProperty(&mesh->weights, err, o, "weights", false);

  ParseExtensionsProperty(&mesh->extensions, err, o);
  ParseExtrasProperty(&(mesh->extras), o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        mesh->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        mesh->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  return true;
}

static bool ParseNode(Node *node, std::string *err, const json &o,
                      bool store_original_json_for_extras_and_extensions) {
  ParseStringProperty(&node->name, err, o, "name", false);

  int skin = -1;
  ParseIntegerProperty(&skin, err, o, "skin", false);
  node->skin = skin;

  // Matrix and T/R/S are exclusive
  if (!ParseNumberArrayProperty(&node->matrix, err, o, "matrix", false)) {
    ParseNumberArrayProperty(&node->rotation, err, o, "rotation", false);
    ParseNumberArrayProperty(&node->scale, err, o, "scale", false);
    ParseNumberArrayProperty(&node->translation, err, o, "translation", false);
  }

  int camera = -1;
  ParseIntegerProperty(&camera, err, o, "camera", false);
  node->camera = camera;

  int mesh = -1;
  ParseIntegerProperty(&mesh, err, o, "mesh", false);
  node->mesh = mesh;

  node->children.clear();
  ParseIntegerArrayProperty(&node->children, err, o, "children", false);

  ParseNumberArrayProperty(&node->weights, err, o, "weights", false);

  ParseExtensionsProperty(&node->extensions, err, o);
  ParseExtrasProperty(&(node->extras), o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        node->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        node->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  return true;
}

static bool ParsePbrMetallicRoughness(
    PbrMetallicRoughness *pbr, std::string *err, const json &o,
    bool store_original_json_for_extras_and_extensions) {
  if (pbr == nullptr) {
    return false;
  }

  std::vector<double> baseColorFactor;
  if (ParseNumberArrayProperty(&baseColorFactor, err, o, "baseColorFactor",
                               /* required */ false)) {
    if (baseColorFactor.size() != 4) {
      if (err) {
        (*err) +=
            "Array length of `baseColorFactor` parameter in "
            "pbrMetallicRoughness must be 4, but got " +
            std::to_string(baseColorFactor.size()) + "\n";
      }
      return false;
    }
    pbr->baseColorFactor = baseColorFactor;
  }

  {
    json_const_iterator it;
    if (FindMember(o, "baseColorTexture", it)) {
      ParseTextureInfo(&pbr->baseColorTexture, err, GetValue(it),
                       store_original_json_for_extras_and_extensions);
    }
  }

  {
    json_const_iterator it;
    if (FindMember(o, "metallicRoughnessTexture", it)) {
      ParseTextureInfo(&pbr->metallicRoughnessTexture, err, GetValue(it),
                       store_original_json_for_extras_and_extensions);
    }
  }

  ParseNumberProperty(&pbr->metallicFactor, err, o, "metallicFactor", false);
  ParseNumberProperty(&pbr->roughnessFactor, err, o, "roughnessFactor", false);

  ParseExtensionsProperty(&pbr->extensions, err, o);
  ParseExtrasProperty(&pbr->extras, o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        pbr->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        pbr->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  return true;
}

static bool ParseMaterial(Material *material, std::string *err, const json &o,
                          bool store_original_json_for_extras_and_extensions) {
  ParseStringProperty(&material->name, err, o, "name", /* required */ false);

  if (ParseNumberArrayProperty(&material->emissiveFactor, err, o,
                               "emissiveFactor",
                               /* required */ false)) {
    if (material->emissiveFactor.size() != 3) {
      if (err) {
        (*err) +=
            "Array length of `emissiveFactor` parameter in "
            "material must be 3, but got " +
            std::to_string(material->emissiveFactor.size()) + "\n";
      }
      return false;
    }
  } else {
    // fill with default values
    material->emissiveFactor = {0.0, 0.0, 0.0};
  }

  ParseStringProperty(&material->alphaMode, err, o, "alphaMode",
                      /* required */ false);
  ParseNumberProperty(&material->alphaCutoff, err, o, "alphaCutoff",
                      /* required */ false);
  ParseBooleanProperty(&material->doubleSided, err, o, "doubleSided",
                       /* required */ false);

  {
    json_const_iterator it;
    if (FindMember(o, "pbrMetallicRoughness", it)) {
      ParsePbrMetallicRoughness(&material->pbrMetallicRoughness, err,
                                GetValue(it),
                                store_original_json_for_extras_and_extensions);
    }
  }

  {
    json_const_iterator it;
    if (FindMember(o, "normalTexture", it)) {
      ParseNormalTextureInfo(&material->normalTexture, err, GetValue(it),
                             store_original_json_for_extras_and_extensions);
    }
  }

  {
    json_const_iterator it;
    if (FindMember(o, "occlusionTexture", it)) {
      ParseOcclusionTextureInfo(&material->occlusionTexture, err, GetValue(it),
                                store_original_json_for_extras_and_extensions);
    }
  }

  {
    json_const_iterator it;
    if (FindMember(o, "emissiveTexture", it)) {
      ParseTextureInfo(&material->emissiveTexture, err, GetValue(it),
                       store_original_json_for_extras_and_extensions);
    }
  }

  // Old code path. For backward compatibility, we still store material values
  // as Parameter. This will create duplicated information for
  // example(pbrMetallicRoughness), but should be neglible in terms of memory
  // consumption.
  // TODO(syoyo): Remove in the next major release.
  material->values.clear();
  material->additionalValues.clear();

  json_const_iterator it(ObjectBegin(o));
  json_const_iterator itEnd(ObjectEnd(o));

  for (; it != itEnd; ++it) {
    std::string key(GetKey(it));
    if (key == "pbrMetallicRoughness") {
      if (IsObject(GetValue(it))) {
        const json &values_object = GetValue(it);

        json_const_iterator itVal(ObjectBegin(values_object));
        json_const_iterator itValEnd(ObjectEnd(values_object));

        for (; itVal != itValEnd; ++itVal) {
          Parameter param;
          if (ParseParameterProperty(&param, err, values_object, GetKey(itVal),
                                     false)) {
            material->values.emplace(GetKey(itVal), std::move(param));
          }
        }
      }
    } else if (key == "extensions" || key == "extras") {
      // done later, skip, otherwise poorly parsed contents will be saved in the
      // parametermap and serialized again later
    } else {
      Parameter param;
      if (ParseParameterProperty(&param, err, o, key, false)) {
        // names of materials have already been parsed. Putting it in this map
        // doesn't correctly reflext the glTF specification
        if (key != "name")
          material->additionalValues.emplace(std::move(key), std::move(param));
      }
    }
  }

  material->extensions.clear();
  ParseExtensionsProperty(&material->extensions, err, o);
  ParseExtrasProperty(&(material->extras), o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator eit;
      if (FindMember(o, "extensions", eit)) {
        material->extensions_json_string = JsonToString(GetValue(eit));
      }
    }
    {
      json_const_iterator eit;
      if (FindMember(o, "extras", eit)) {
        material->extras_json_string = JsonToString(GetValue(eit));
      }
    }
  }

  return true;
}

static bool ParseAnimationChannel(
    AnimationChannel *channel, std::string *err, const json &o,
    bool store_original_json_for_extras_and_extensions) {
  int samplerIndex = -1;
  int targetIndex = -1;
  if (!ParseIntegerProperty(&samplerIndex, err, o, "sampler", true,
                            "AnimationChannel")) {
    if (err) {
      (*err) += "`sampler` field is missing in animation channels\n";
    }
    return false;
  }

  json_const_iterator targetIt;
  if (FindMember(o, "target", targetIt) && IsObject(GetValue(targetIt))) {
    const json &target_object = GetValue(targetIt);

    if (!ParseIntegerProperty(&targetIndex, err, target_object, "node", true)) {
      if (err) {
        (*err) += "`node` field is missing in animation.channels.target\n";
      }
      return false;
    }

    if (!ParseStringProperty(&channel->target_path, err, target_object, "path",
                             true)) {
      if (err) {
        (*err) += "`path` field is missing in animation.channels.target\n";
      }
      return false;
    }
    ParseExtensionsProperty(&channel->target_extensions, err, target_object);
    if (store_original_json_for_extras_and_extensions) {
      json_const_iterator it;
      if (FindMember(target_object, "extensions", it)) {
        channel->target_extensions_json_string = JsonToString(GetValue(it));
      }
    }
  }

  channel->sampler = samplerIndex;
  channel->target_node = targetIndex;

  ParseExtensionsProperty(&channel->extensions, err, o);
  ParseExtrasProperty(&(channel->extras), o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        channel->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        channel->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  return true;
}

static bool ParseAnimation(Animation *animation, std::string *err,
                           const json &o,
                           bool store_original_json_for_extras_and_extensions) {
  {
    json_const_iterator channelsIt;
    if (FindMember(o, "channels", channelsIt) &&
        IsArray(GetValue(channelsIt))) {
      json_const_array_iterator channelEnd = ArrayEnd(GetValue(channelsIt));
      for (json_const_array_iterator i = ArrayBegin(GetValue(channelsIt));
           i != channelEnd; ++i) {
        AnimationChannel channel;
        if (ParseAnimationChannel(
                &channel, err, *i,
                store_original_json_for_extras_and_extensions)) {
          // Only add the channel if the parsing succeeds.
          animation->channels.emplace_back(std::move(channel));
        }
      }
    }
  }

  {
    json_const_iterator samplerIt;
    if (FindMember(o, "samplers", samplerIt) && IsArray(GetValue(samplerIt))) {
      const json &sampler_array = GetValue(samplerIt);

      json_const_array_iterator it = ArrayBegin(sampler_array);
      json_const_array_iterator itEnd = ArrayEnd(sampler_array);

      for (; it != itEnd; ++it) {
        const json &s = *it;

        AnimationSampler sampler;
        int inputIndex = -1;
        int outputIndex = -1;
        if (!ParseIntegerProperty(&inputIndex, err, s, "input", true)) {
          if (err) {
            (*err) += "`input` field is missing in animation.sampler\n";
          }
          return false;
        }
        ParseStringProperty(&sampler.interpolation, err, s, "interpolation",
                            false);
        if (!ParseIntegerProperty(&outputIndex, err, s, "output", true)) {
          if (err) {
            (*err) += "`output` field is missing in animation.sampler\n";
          }
          return false;
        }
        sampler.input = inputIndex;
        sampler.output = outputIndex;
        ParseExtensionsProperty(&(sampler.extensions), err, o);
        ParseExtrasProperty(&(sampler.extras), s);

        if (store_original_json_for_extras_and_extensions) {
          {
            json_const_iterator eit;
            if (FindMember(o, "extensions", eit)) {
              sampler.extensions_json_string = JsonToString(GetValue(eit));
            }
          }
          {
            json_const_iterator eit;
            if (FindMember(o, "extras", eit)) {
              sampler.extras_json_string = JsonToString(GetValue(eit));
            }
          }
        }

        animation->samplers.emplace_back(std::move(sampler));
      }
    }
  }

  ParseStringProperty(&animation->name, err, o, "name", false);

  ParseExtensionsProperty(&animation->extensions, err, o);
  ParseExtrasProperty(&(animation->extras), o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        animation->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        animation->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  return true;
}

static bool ParseSampler(Sampler *sampler, std::string *err, const json &o,
                         bool store_original_json_for_extras_and_extensions) {
  ParseStringProperty(&sampler->name, err, o, "name", false);

  int minFilter = -1;
  int magFilter = -1;
  int wrapS = TINYGLTF_TEXTURE_WRAP_REPEAT;
  int wrapT = TINYGLTF_TEXTURE_WRAP_REPEAT;
  int wrapR = TINYGLTF_TEXTURE_WRAP_REPEAT;
  ParseIntegerProperty(&minFilter, err, o, "minFilter", false);
  ParseIntegerProperty(&magFilter, err, o, "magFilter", false);
  ParseIntegerProperty(&wrapS, err, o, "wrapS", false);
  ParseIntegerProperty(&wrapT, err, o, "wrapT", false);
  ParseIntegerProperty(&wrapR, err, o, "wrapR", false);  // tinygltf extension

  // TODO(syoyo): Check the value is alloed one.
  // (e.g. we allow 9728(NEAREST), but don't allow 9727)

  sampler->minFilter = minFilter;
  sampler->magFilter = magFilter;
  sampler->wrapS = wrapS;
  sampler->wrapT = wrapT;
  sampler->wrapR = wrapR;

  ParseExtensionsProperty(&(sampler->extensions), err, o);
  ParseExtrasProperty(&(sampler->extras), o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        sampler->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        sampler->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  return true;
}

static bool ParseSkin(Skin *skin, std::string *err, const json &o,
                      bool store_original_json_for_extras_and_extensions) {
  ParseStringProperty(&skin->name, err, o, "name", false, "Skin");

  std::vector<int> joints;
  if (!ParseIntegerArrayProperty(&joints, err, o, "joints", false, "Skin")) {
    return false;
  }
  skin->joints = std::move(joints);

  int skeleton = -1;
  ParseIntegerProperty(&skeleton, err, o, "skeleton", false, "Skin");
  skin->skeleton = skeleton;

  int invBind = -1;
  ParseIntegerProperty(&invBind, err, o, "inverseBindMatrices", true, "Skin");
  skin->inverseBindMatrices = invBind;

  ParseExtensionsProperty(&(skin->extensions), err, o);
  ParseExtrasProperty(&(skin->extras), o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        skin->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        skin->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  return true;
}

static bool ParsePerspectiveCamera(
    PerspectiveCamera *camera, std::string *err, const json &o,
    bool store_original_json_for_extras_and_extensions) {
  double yfov = 0.0;
  if (!ParseNumberProperty(&yfov, err, o, "yfov", true, "OrthographicCamera")) {
    return false;
  }

  double znear = 0.0;
  if (!ParseNumberProperty(&znear, err, o, "znear", true,
                           "PerspectiveCamera")) {
    return false;
  }

  double aspectRatio = 0.0;  // = invalid
  ParseNumberProperty(&aspectRatio, err, o, "aspectRatio", false,
                      "PerspectiveCamera");

  double zfar = 0.0;  // = invalid
  ParseNumberProperty(&zfar, err, o, "zfar", false, "PerspectiveCamera");

  camera->aspectRatio = aspectRatio;
  camera->zfar = zfar;
  camera->yfov = yfov;
  camera->znear = znear;

  ParseExtensionsProperty(&camera->extensions, err, o);
  ParseExtrasProperty(&(camera->extras), o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        camera->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        camera->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  // TODO(syoyo): Validate parameter values.

  return true;
}

static bool ParseSpotLight(SpotLight *light, std::string *err, const json &o,
                           bool store_original_json_for_extras_and_extensions) {
  ParseNumberProperty(&light->innerConeAngle, err, o, "innerConeAngle", false);
  ParseNumberProperty(&light->outerConeAngle, err, o, "outerConeAngle", false);

  ParseExtensionsProperty(&light->extensions, err, o);
  ParseExtrasProperty(&light->extras, o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        light->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        light->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  // TODO(syoyo): Validate parameter values.

  return true;
}

static bool ParseOrthographicCamera(
    OrthographicCamera *camera, std::string *err, const json &o,
    bool store_original_json_for_extras_and_extensions) {
  double xmag = 0.0;
  if (!ParseNumberProperty(&xmag, err, o, "xmag", true, "OrthographicCamera")) {
    return false;
  }

  double ymag = 0.0;
  if (!ParseNumberProperty(&ymag, err, o, "ymag", true, "OrthographicCamera")) {
    return false;
  }

  double zfar = 0.0;
  if (!ParseNumberProperty(&zfar, err, o, "zfar", true, "OrthographicCamera")) {
    return false;
  }

  double znear = 0.0;
  if (!ParseNumberProperty(&znear, err, o, "znear", true,
                           "OrthographicCamera")) {
    return false;
  }

  ParseExtensionsProperty(&camera->extensions, err, o);
  ParseExtrasProperty(&(camera->extras), o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        camera->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        camera->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  camera->xmag = xmag;
  camera->ymag = ymag;
  camera->zfar = zfar;
  camera->znear = znear;

  // TODO(syoyo): Validate parameter values.

  return true;
}

static bool ParseCamera(Camera *camera, std::string *err, const json &o,
                        bool store_original_json_for_extras_and_extensions) {
  if (!ParseStringProperty(&camera->type, err, o, "type", true, "Camera")) {
    return false;
  }

  if (camera->type.compare("orthographic") == 0) {
    json_const_iterator orthoIt;
    if (!FindMember(o, "orthographic", orthoIt)) {
      if (err) {
        std::stringstream ss;
        ss << "Orhographic camera description not found." << std::endl;
        (*err) += ss.str();
      }
      return false;
    }

    const json &v = GetValue(orthoIt);
    if (!IsObject(v)) {
      if (err) {
        std::stringstream ss;
        ss << "\"orthographic\" is not a JSON object." << std::endl;
        (*err) += ss.str();
      }
      return false;
    }

    if (!ParseOrthographicCamera(
            &camera->orthographic, err, v,
            store_original_json_for_extras_and_extensions)) {
      return false;
    }
  } else if (camera->type.compare("perspective") == 0) {
    json_const_iterator perspIt;
    if (!FindMember(o, "perspective", perspIt)) {
      if (err) {
        std::stringstream ss;
        ss << "Perspective camera description not found." << std::endl;
        (*err) += ss.str();
      }
      return false;
    }

    const json &v = GetValue(perspIt);
    if (!IsObject(v)) {
      if (err) {
        std::stringstream ss;
        ss << "\"perspective\" is not a JSON object." << std::endl;
        (*err) += ss.str();
      }
      return false;
    }

    if (!ParsePerspectiveCamera(
            &camera->perspective, err, v,
            store_original_json_for_extras_and_extensions)) {
      return false;
    }
  } else {
    if (err) {
      std::stringstream ss;
      ss << "Invalid camera type: \"" << camera->type
         << "\". Must be \"perspective\" or \"orthographic\"" << std::endl;
      (*err) += ss.str();
    }
    return false;
  }

  ParseStringProperty(&camera->name, err, o, "name", false);

  ParseExtensionsProperty(&camera->extensions, err, o);
  ParseExtrasProperty(&(camera->extras), o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        camera->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        camera->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  return true;
}

static bool ParseLight(Light *light, std::string *err, const json &o,
                       bool store_original_json_for_extras_and_extensions) {
  if (!ParseStringProperty(&light->type, err, o, "type", true)) {
    return false;
  }

  if (light->type == "spot") {
    json_const_iterator spotIt;
    if (!FindMember(o, "spot", spotIt)) {
      if (err) {
        std::stringstream ss;
        ss << "Spot light description not found." << std::endl;
        (*err) += ss.str();
      }
      return false;
    }

    const json &v = GetValue(spotIt);
    if (!IsObject(v)) {
      if (err) {
        std::stringstream ss;
        ss << "\"spot\" is not a JSON object." << std::endl;
        (*err) += ss.str();
      }
      return false;
    }

    if (!ParseSpotLight(&light->spot, err, v,
                        store_original_json_for_extras_and_extensions)) {
      return false;
    }
  }

  ParseStringProperty(&light->name, err, o, "name", false);
  ParseNumberArrayProperty(&light->color, err, o, "color", false);
  ParseNumberProperty(&light->range, err, o, "range", false);
  ParseNumberProperty(&light->intensity, err, o, "intensity", false);
  ParseExtensionsProperty(&light->extensions, err, o);
  ParseExtrasProperty(&(light->extras), o);

  if (store_original_json_for_extras_and_extensions) {
    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        light->extensions_json_string = JsonToString(GetValue(it));
      }
    }
    {
      json_const_iterator it;
      if (FindMember(o, "extras", it)) {
        light->extras_json_string = JsonToString(GetValue(it));
      }
    }
  }

  return true;
}

bool TinyGLTF::LoadFromString(Model *model, std::string *err, std::string *warn,
                              const char *json_str,
                              unsigned int json_str_length,
                              const std::string &base_dir,
                              unsigned int check_sections) {
  if (json_str_length < 4) {
    if (err) {
      (*err) = "JSON string too short.\n";
    }
    return false;
  }

  JsonDocument v;

#if (defined(__cpp_exceptions) || defined(__EXCEPTIONS) || \
     defined(_CPPUNWIND)) &&                               \
    !defined(TINYGLTF_NOEXCEPTION)
  try {
    JsonParse(v, json_str, json_str_length, true);

  } catch (const std::exception &e) {
    if (err) {
      (*err) = e.what();
    }
    return false;
  }
#else
  {
    JsonParse(v, json_str, json_str_length);

    if (!IsObject(v)) {
      // Assume parsing was failed.
      if (err) {
        (*err) = "Failed to parse JSON object\n";
      }
      return false;
    }
  }
#endif

  if (!IsObject(v)) {
    // root is not an object.
    if (err) {
      (*err) = "Root element is not a JSON object\n";
    }
    return false;
  }

  {
    bool version_found = false;
    json_const_iterator it;
    if (FindMember(v, "asset", it) && IsObject(GetValue(it))) {
      auto &itObj = GetValue(it);
      json_const_iterator version_it;
      std::string versionStr;
      if (FindMember(itObj, "version", version_it) &&
          GetString(GetValue(version_it), versionStr)) {
        version_found = true;
      }
    }
    if (version_found) {
      // OK
    } else if (check_sections & REQUIRE_VERSION) {
      if (err) {
        (*err) += "\"asset\" object not found in .gltf or not an object type\n";
      }
      return false;
    }
  }

  // scene is not mandatory.
  // FIXME Maybe a better way to handle it than removing the code

  auto IsArrayMemberPresent = [](const json &_v, const char *name) -> bool {
    json_const_iterator it;
    return FindMember(_v, name, it) && IsArray(GetValue(it));
  };

  {
    if ((check_sections & REQUIRE_SCENES) &&
        !IsArrayMemberPresent(v, "scenes")) {
      if (err) {
        (*err) += "\"scenes\" object not found in .gltf or not an array type\n";
      }
      return false;
    }
  }

  {
    if ((check_sections & REQUIRE_NODES) && !IsArrayMemberPresent(v, "nodes")) {
      if (err) {
        (*err) += "\"nodes\" object not found in .gltf\n";
      }
      return false;
    }
  }

  {
    if ((check_sections & REQUIRE_ACCESSORS) &&
        !IsArrayMemberPresent(v, "accessors")) {
      if (err) {
        (*err) += "\"accessors\" object not found in .gltf\n";
      }
      return false;
    }
  }

  {
    if ((check_sections & REQUIRE_BUFFERS) &&
        !IsArrayMemberPresent(v, "buffers")) {
      if (err) {
        (*err) += "\"buffers\" object not found in .gltf\n";
      }
      return false;
    }
  }

  {
    if ((check_sections & REQUIRE_BUFFER_VIEWS) &&
        !IsArrayMemberPresent(v, "bufferViews")) {
      if (err) {
        (*err) += "\"bufferViews\" object not found in .gltf\n";
      }
      return false;
    }
  }

  model->buffers.clear();
  model->bufferViews.clear();
  model->accessors.clear();
  model->meshes.clear();
  model->cameras.clear();
  model->nodes.clear();
  model->extensionsUsed.clear();
  model->extensionsRequired.clear();
  model->extensions.clear();
  model->defaultScene = -1;

  // 1. Parse Asset
  {
    json_const_iterator it;
    if (FindMember(v, "asset", it) && IsObject(GetValue(it))) {
      const json &root = GetValue(it);

      ParseAsset(&model->asset, err, root,
                 store_original_json_for_extras_and_extensions_);
    }
  }

#ifdef TINYGLTF_USE_CPP14
  auto ForEachInArray = [](const json &_v, const char *member,
                           const auto &cb) -> bool
#else
  // The std::function<> implementation can be less efficient because it will
  // allocate heap when the size of the captured lambda is above 16 bytes with
  // clang and gcc, but it does not require C++14.
  auto ForEachInArray = [](const json &_v, const char *member,
                           const std::function<bool(const json &)> &cb) -> bool
#endif
  {
    json_const_iterator itm;
    if (FindMember(_v, member, itm) && IsArray(GetValue(itm))) {
      const json &root = GetValue(itm);
      auto it = ArrayBegin(root);
      auto end = ArrayEnd(root);
      for (; it != end; ++it) {
        if (!cb(*it)) return false;
      }
    }
    return true;
  };

  // 2. Parse extensionUsed
  {
    ForEachInArray(v, "extensionsUsed", [&](const json &o) {
      std::string str;
      GetString(o, str);
      model->extensionsUsed.emplace_back(std::move(str));
      return true;
    });
  }

  {
    ForEachInArray(v, "extensionsRequired", [&](const json &o) {
      std::string str;
      GetString(o, str);
      model->extensionsRequired.emplace_back(std::move(str));
      return true;
    });
  }

  // 3. Parse Buffer
  {
    bool success = ForEachInArray(v, "buffers", [&](const json &o) {
      if (!IsObject(o)) {
        if (err) {
          (*err) += "`buffers' does not contain an JSON object.";
        }
        return false;
      }
      Buffer buffer;
      if (!ParseBuffer(&buffer, err, o,
                       store_original_json_for_extras_and_extensions_, &fs,
                       base_dir, is_binary_, bin_data_, bin_size_)) {
        return false;
      }

      model->buffers.emplace_back(std::move(buffer));
      return true;
    });

    if (!success) {
      return false;
    }
  }
  // 4. Parse BufferView
  {
    bool success = ForEachInArray(v, "bufferViews", [&](const json &o) {
      if (!IsObject(o)) {
        if (err) {
          (*err) += "`bufferViews' does not contain an JSON object.";
        }
        return false;
      }
      BufferView bufferView;
      if (!ParseBufferView(&bufferView, err, o,
                           store_original_json_for_extras_and_extensions_)) {
        return false;
      }

      model->bufferViews.emplace_back(std::move(bufferView));
      return true;
    });

    if (!success) {
      return false;
    }
  }

  // 5. Parse Accessor
  {
    bool success = ForEachInArray(v, "accessors", [&](const json &o) {
      if (!IsObject(o)) {
        if (err) {
          (*err) += "`accessors' does not contain an JSON object.";
        }
        return false;
      }
      Accessor accessor;
      if (!ParseAccessor(&accessor, err, o,
                         store_original_json_for_extras_and_extensions_)) {
        return false;
      }

      model->accessors.emplace_back(std::move(accessor));
      return true;
    });

    if (!success) {
      return false;
    }
  }

  // 6. Parse Mesh
  {
    bool success = ForEachInArray(v, "meshes", [&](const json &o) {
      if (!IsObject(o)) {
        if (err) {
          (*err) += "`meshes' does not contain an JSON object.";
        }
        return false;
      }
      Mesh mesh;
      if (!ParseMesh(&mesh, model, err, o,
                     store_original_json_for_extras_and_extensions_)) {
        return false;
      }

      model->meshes.emplace_back(std::move(mesh));
      return true;
    });

    if (!success) {
      return false;
    }
  }

  // Assign missing bufferView target types
  // - Look for missing Mesh indices
  // - Look for missing Mesh attributes
  for (auto &mesh : model->meshes) {
    for (auto &primitive : mesh.primitives) {
      if (primitive.indices >
          -1)  // has indices from parsing step, must be Element Array Buffer
      {
        if (size_t(primitive.indices) >= model->accessors.size()) {
          if (err) {
            (*err) += "primitive indices accessor out of bounds";
          }
          return false;
        }

        auto bufferView =
            model->accessors[size_t(primitive.indices)].bufferView;
        if (bufferView < 0 || size_t(bufferView) >= model->bufferViews.size()) {
          if (err) {
            (*err) += "accessor[" + std::to_string(primitive.indices) +
                      "] invalid bufferView";
          }
          return false;
        }

        model->bufferViews[size_t(bufferView)].target =
            TINYGLTF_TARGET_ELEMENT_ARRAY_BUFFER;
        // we could optionally check if acessors' bufferView type is Scalar, as
        // it should be
      }

      for (auto &attribute : primitive.attributes) {
        model
            ->bufferViews[size_t(
                model->accessors[size_t(attribute.second)].bufferView)]
            .target = TINYGLTF_TARGET_ARRAY_BUFFER;
      }

      for (auto &target : primitive.targets) {
        for (auto &attribute : target) {
          model
              ->bufferViews[size_t(
                  model->accessors[size_t(attribute.second)].bufferView)]
              .target = TINYGLTF_TARGET_ARRAY_BUFFER;
        }
      }
    }
  }

  // 7. Parse Node
  {
    bool success = ForEachInArray(v, "nodes", [&](const json &o) {
      if (!IsObject(o)) {
        if (err) {
          (*err) += "`nodes' does not contain an JSON object.";
        }
        return false;
      }
      Node node;
      if (!ParseNode(&node, err, o,
                     store_original_json_for_extras_and_extensions_)) {
        return false;
      }

      model->nodes.emplace_back(std::move(node));
      return true;
    });

    if (!success) {
      return false;
    }
  }

  // 8. Parse scenes.
  {
    bool success = ForEachInArray(v, "scenes", [&](const json &o) {
      if (!IsObject(o)) {
        if (err) {
          (*err) += "`scenes' does not contain an JSON object.";
        }
        return false;
      }
      std::vector<int> nodes;
      ParseIntegerArrayProperty(&nodes, err, o, "nodes", false);

      Scene scene;
      scene.nodes = std::move(nodes);

      ParseStringProperty(&scene.name, err, o, "name", false);

      ParseExtensionsProperty(&scene.extensions, err, o);
      ParseExtrasProperty(&scene.extras, o);

      if (store_original_json_for_extras_and_extensions_) {
        {
          json_const_iterator it;
          if (FindMember(o, "extensions", it)) {
            model->extensions_json_string = JsonToString(GetValue(it));
          }
        }
        {
          json_const_iterator it;
          if (FindMember(o, "extras", it)) {
            model->extras_json_string = JsonToString(GetValue(it));
          }
        }
      }

      model->scenes.emplace_back(std::move(scene));
      return true;
    });

    if (!success) {
      return false;
    }
  }

  // 9. Parse default scenes.
  {
    json_const_iterator rootIt;
    int iVal;
    if (FindMember(v, "scene", rootIt) && GetInt(GetValue(rootIt), iVal)) {
      model->defaultScene = iVal;
    }
  }

  // 10. Parse Material
  {
    bool success = ForEachInArray(v, "materials", [&](const json &o) {
      if (!IsObject(o)) {
        if (err) {
          (*err) += "`materials' does not contain an JSON object.";
        }
        return false;
      }
      Material material;
      ParseStringProperty(&material.name, err, o, "name", false);

      if (!ParseMaterial(&material, err, o,
                         store_original_json_for_extras_and_extensions_)) {
        return false;
      }

      model->materials.emplace_back(std::move(material));
      return true;
    });

    if (!success) {
      return false;
    }
  }

  // 11. Parse Image
  {
    int idx = 0;
    bool success = ForEachInArray(v, "images", [&](const json &o) {
      if (!IsObject(o)) {
        if (err) {
          (*err) += "image[" + std::to_string(idx) + "] is not a JSON object.";
        }
        return false;
      }
      Image image;
      if (!ParseImage(&image, idx, err, warn, o,
                      store_original_json_for_extras_and_extensions_, base_dir,
                      &fs, &this->LoadImageData, load_image_user_data_)) {
        return false;
      }

      if (image.bufferView != -1) {
        // Load image from the buffer view.
        if (size_t(image.bufferView) >= model->bufferViews.size()) {
          if (err) {
            std::stringstream ss;
            ss << "image[" << idx << "] bufferView \"" << image.bufferView
               << "\" not found in the scene." << std::endl;
            (*err) += ss.str();
          }
          return false;
        }

        const BufferView &bufferView =
            model->bufferViews[size_t(image.bufferView)];
        if (size_t(bufferView.buffer) >= model->buffers.size()) {
          if (err) {
            std::stringstream ss;
            ss << "image[" << idx << "] buffer \"" << bufferView.buffer
               << "\" not found in the scene." << std::endl;
            (*err) += ss.str();
          }
          return false;
        }
        const Buffer &buffer = model->buffers[size_t(bufferView.buffer)];

        if (*LoadImageData == nullptr) {
          if (err) {
            (*err) += "No LoadImageData callback specified.\n";
          }
          return false;
        }
        bool ret = LoadImageData(
            &image, idx, err, warn, image.width, image.height,
            &buffer.data[bufferView.byteOffset],
            static_cast<int>(bufferView.byteLength), load_image_user_data_);
        if (!ret) {
          return false;
        }
      }

      model->images.emplace_back(std::move(image));
      ++idx;
      return true;
    });

    if (!success) {
      return false;
    }
  }

  // 12. Parse Texture
  {
    bool success = ForEachInArray(v, "textures", [&](const json &o) {
      if (!IsObject(o)) {
        if (err) {
          (*err) += "`textures' does not contain an JSON object.";
        }
        return false;
      }
      Texture texture;
      if (!ParseTexture(&texture, err, o,
                        store_original_json_for_extras_and_extensions_,
                        base_dir)) {
        return false;
      }

      model->textures.emplace_back(std::move(texture));
      return true;
    });

    if (!success) {
      return false;
    }
  }

  // 13. Parse Animation
  {
    bool success = ForEachInArray(v, "animations", [&](const json &o) {
      if (!IsObject(o)) {
        if (err) {
          (*err) += "`animations' does not contain an JSON object.";
        }
        return false;
      }
      Animation animation;
      if (!ParseAnimation(&animation, err, o,
                          store_original_json_for_extras_and_extensions_)) {
        return false;
      }

      model->animations.emplace_back(std::move(animation));
      return true;
    });

    if (!success) {
      return false;
    }
  }

  // 14. Parse Skin
  {
    bool success = ForEachInArray(v, "skins", [&](const json &o) {
      if (!IsObject(o)) {
        if (err) {
          (*err) += "`skins' does not contain an JSON object.";
        }
        return false;
      }
      Skin skin;
      if (!ParseSkin(&skin, err, o,
                     store_original_json_for_extras_and_extensions_)) {
        return false;
      }

      model->skins.emplace_back(std::move(skin));
      return true;
    });

    if (!success) {
      return false;
    }
  }

  // 15. Parse Sampler
  {
    bool success = ForEachInArray(v, "samplers", [&](const json &o) {
      if (!IsObject(o)) {
        if (err) {
          (*err) += "`samplers' does not contain an JSON object.";
        }
        return false;
      }
      Sampler sampler;
      if (!ParseSampler(&sampler, err, o,
                        store_original_json_for_extras_and_extensions_)) {
        return false;
      }

      model->samplers.emplace_back(std::move(sampler));
      return true;
    });

    if (!success) {
      return false;
    }
  }

  // 16. Parse Camera
  {
    bool success = ForEachInArray(v, "cameras", [&](const json &o) {
      if (!IsObject(o)) {
        if (err) {
          (*err) += "`cameras' does not contain an JSON object.";
        }
        return false;
      }
      Camera camera;
      if (!ParseCamera(&camera, err, o,
                       store_original_json_for_extras_and_extensions_)) {
        return false;
      }

      model->cameras.emplace_back(std::move(camera));
      return true;
    });

    if (!success) {
      return false;
    }
  }

  // 17. Parse Extensions
  ParseExtensionsProperty(&model->extensions, err, v);

  // 18. Specific extension implementations
  {
    json_const_iterator rootIt;
    if (FindMember(v, "extensions", rootIt) && IsObject(GetValue(rootIt))) {
      const json &root = GetValue(rootIt);

      json_const_iterator it(ObjectBegin(root));
      json_const_iterator itEnd(ObjectEnd(root));
      for (; it != itEnd; ++it) {
        // parse KHR_lights_punctual extension
        std::string key(GetKey(it));
        if ((key == "KHR_lights_punctual") && IsObject(GetValue(it))) {
          const json &object = GetValue(it);
          json_const_iterator itLight;
          if (FindMember(object, "lights", itLight)) {
            const json &lights = GetValue(itLight);
            if (!IsArray(lights)) {
              continue;
            }

            auto arrayIt(ArrayBegin(lights));
            auto arrayItEnd(ArrayEnd(lights));
            for (; arrayIt != arrayItEnd; ++arrayIt) {
              Light light;
              if (!ParseLight(&light, err, *arrayIt,
                              store_original_json_for_extras_and_extensions_)) {
                return false;
              }
              model->lights.emplace_back(std::move(light));
            }
          }
        }
      }
    }
  }

  // 19. Parse Extras
  ParseExtrasProperty(&model->extras, v);

  if (store_original_json_for_extras_and_extensions_) {
    model->extras_json_string = JsonToString(v["extras"]);
    model->extensions_json_string = JsonToString(v["extensions"]);
  }

  return true;
}

bool TinyGLTF::LoadASCIIFromString(Model *model, std::string *err,
                                   std::string *warn, const char *str,
                                   unsigned int length,
                                   const std::string &base_dir,
                                   unsigned int check_sections) {
  is_binary_ = false;
  bin_data_ = nullptr;
  bin_size_ = 0;

  return LoadFromString(model, err, warn, str, length, base_dir,
                        check_sections);
}

bool TinyGLTF::LoadASCIIFromFile(Model *model, std::string *err,
                                 std::string *warn, const std::string &filename,
                                 unsigned int check_sections) {
  std::stringstream ss;

  if (fs.ReadWholeFile == nullptr) {
    // Programmer error, assert() ?
    ss << "Failed to read file: " << filename
       << ": one or more FS callback not set" << std::endl;
    if (err) {
      (*err) = ss.str();
    }
    return false;
  }

  std::vector<unsigned char> data;
  std::string fileerr;
  bool fileread = fs.ReadWholeFile(&data, &fileerr, filename, fs.user_data);
  if (!fileread) {
    ss << "Failed to read file: " << filename << ": " << fileerr << std::endl;
    if (err) {
      (*err) = ss.str();
    }
    return false;
  }

  size_t sz = data.size();
  if (sz == 0) {
    if (err) {
      (*err) = "Empty file.";
    }
    return false;
  }

  std::string basedir = GetBaseDir(filename);

  bool ret = LoadASCIIFromString(
      model, err, warn, reinterpret_cast<const char *>(&data.at(0)),
      static_cast<unsigned int>(data.size()), basedir, check_sections);

  return ret;
}

bool TinyGLTF::LoadBinaryFromMemory(Model *model, std::string *err,
                                    std::string *warn,
                                    const unsigned char *bytes,
                                    unsigned int size,
                                    const std::string &base_dir,
                                    unsigned int check_sections) {
  if (size < 20) {
    if (err) {
      (*err) = "Too short data size for glTF Binary.";
    }
    return false;
  }

  if (bytes[0] == 'g' && bytes[1] == 'l' && bytes[2] == 'T' &&
      bytes[3] == 'F') {
    // ok
  } else {
    if (err) {
      (*err) = "Invalid magic.";
    }
    return false;
  }

  unsigned int version;       // 4 bytes
  unsigned int length;        // 4 bytes
  unsigned int model_length;  // 4 bytes
  unsigned int model_format;  // 4 bytes;

  // @todo { Endian swap for big endian machine. }
  memcpy(&version, bytes + 4, 4);
  swap4(&version);
  memcpy(&length, bytes + 8, 4);
  swap4(&length);
  memcpy(&model_length, bytes + 12, 4);
  swap4(&model_length);
  memcpy(&model_format, bytes + 16, 4);
  swap4(&model_format);

  // In case the Bin buffer is not present, the size is exactly 20 + size of
  // JSON contents,
  // so use "greater than" operator.
  if ((20 + model_length > size) || (model_length < 1) || (length > size) ||
      (20 + model_length > length) ||
      (model_format != 0x4E4F534A)) {  // 0x4E4F534A = JSON format.
    if (err) {
      (*err) = "Invalid glTF binary.";
    }
    return false;
  }

  // Extract JSON string.
  std::string jsonString(reinterpret_cast<const char *>(&bytes[20]),
                         model_length);

  is_binary_ = true;
  bin_data_ = bytes + 20 + model_length +
              8;  // 4 bytes (buffer_length) + 4 bytes(buffer_format)
  bin_size_ =
      length - (20 + model_length);  // extract header + JSON scene data.

  bool ret = LoadFromString(model, err, warn,
                            reinterpret_cast<const char *>(&bytes[20]),
                            model_length, base_dir, check_sections);
  if (!ret) {
    return ret;
  }

  return true;
}

bool TinyGLTF::LoadBinaryFromFile(Model *model, std::string *err,
                                  std::string *warn,
                                  const std::string &filename,
                                  unsigned int check_sections) {
  std::stringstream ss;

  if (fs.ReadWholeFile == nullptr) {
    // Programmer error, assert() ?
    ss << "Failed to read file: " << filename
       << ": one or more FS callback not set" << std::endl;
    if (err) {
      (*err) = ss.str();
    }
    return false;
  }

  std::vector<unsigned char> data;
  std::string fileerr;
  bool fileread = fs.ReadWholeFile(&data, &fileerr, filename, fs.user_data);
  if (!fileread) {
    ss << "Failed to read file: " << filename << ": " << fileerr << std::endl;
    if (err) {
      (*err) = ss.str();
    }
    return false;
  }

  std::string basedir = GetBaseDir(filename);

  bool ret = LoadBinaryFromMemory(model, err, warn, &data.at(0),
                                  static_cast<unsigned int>(data.size()),
                                  basedir, check_sections);

  return ret;
}

///////////////////////
// GLTF Serialization
///////////////////////
namespace {
json JsonFromString(const char *s) {
#ifdef TINYGLTF_USE_RAPIDJSON
  return json(s, GetAllocator());
#else
  return json(s);
#endif
}

void JsonAssign(json &dest, const json &src) {
#ifdef TINYGLTF_USE_RAPIDJSON
  dest.CopyFrom(src, GetAllocator());
#else
  dest = src;
#endif
}

void JsonAddMember(json &o, const char *key, json &&value) {
#ifdef TINYGLTF_USE_RAPIDJSON
  if (!o.IsObject()) {
    o.SetObject();
  }
  o.AddMember(json(key, GetAllocator()), std::move(value), GetAllocator());
#else
  o[key] = std::move(value);
#endif
}

void JsonPushBack(json &o, json &&value) {
#ifdef TINYGLTF_USE_RAPIDJSON
  o.PushBack(std::move(value), GetAllocator());
#else
  o.push_back(std::move(value));
#endif
}

bool JsonIsNull(const json &o) {
#ifdef TINYGLTF_USE_RAPIDJSON
  return o.IsNull();
#else
  return o.is_null();
#endif
}

void JsonSetObject(json &o) {
#ifdef TINYGLTF_USE_RAPIDJSON
  o.SetObject();
#else
  o = o.object({});
#endif
}

void JsonReserveArray(json &o, size_t s) {
#ifdef TINYGLTF_USE_RAPIDJSON
  o.SetArray();
  o.Reserve(static_cast<rapidjson::SizeType>(s), GetAllocator());
#endif
  (void)(o);
  (void)(s);
}
}  // namespace

// typedef std::pair<std::string, json> json_object_pair;

template <typename T>
static void SerializeNumberProperty(const std::string &key, T number,
                                    json &obj) {
  // obj.insert(
  //    json_object_pair(key, json(static_cast<double>(number))));
  // obj[key] = static_cast<double>(number);
  JsonAddMember(obj, key.c_str(), json(number));
}

#ifdef TINYGLTF_USE_RAPIDJSON
template <>
void SerializeNumberProperty(const std::string &key, size_t number, json &obj) {
  JsonAddMember(obj, key.c_str(), json(static_cast<uint64_t>(number)));
}
#endif

template <typename T>
static void SerializeNumberArrayProperty(const std::string &key,
                                         const std::vector<T> &value,
                                         json &obj) {
  if (value.empty()) return;

  json ary;
  JsonReserveArray(ary, value.size());
  for (const auto &s : value) {
    JsonPushBack(ary, json(s));
  }
  JsonAddMember(obj, key.c_str(), std::move(ary));
}

static void SerializeStringProperty(const std::string &key,
                                    const std::string &value, json &obj) {
  JsonAddMember(obj, key.c_str(), JsonFromString(value.c_str()));
}

static void SerializeStringArrayProperty(const std::string &key,
                                         const std::vector<std::string> &value,
                                         json &obj) {
  json ary;
  JsonReserveArray(ary, value.size());
  for (auto &s : value) {
    JsonPushBack(ary, JsonFromString(s.c_str()));
  }
  JsonAddMember(obj, key.c_str(), std::move(ary));
}

static bool ValueToJson(const Value &value, json *ret) {
  json obj;
#ifdef TINYGLTF_USE_RAPIDJSON
  switch (value.Type()) {
    case REAL_TYPE:
      obj.SetDouble(value.Get<double>());
      break;
    case INT_TYPE:
      obj.SetInt(value.Get<int>());
      break;
    case BOOL_TYPE:
      obj.SetBool(value.Get<bool>());
      break;
    case STRING_TYPE:
      obj.SetString(value.Get<std::string>().c_str(), GetAllocator());
      break;
    case ARRAY_TYPE: {
      obj.SetArray();
      obj.Reserve(static_cast<rapidjson::SizeType>(value.ArrayLen()),
                  GetAllocator());
      for (unsigned int i = 0; i < value.ArrayLen(); ++i) {
        Value elementValue = value.Get(int(i));
        json elementJson;
        if (ValueToJson(value.Get(int(i)), &elementJson))
          obj.PushBack(std::move(elementJson), GetAllocator());
      }
      break;
    }
    case BINARY_TYPE:
      // TODO
      // obj = json(value.Get<std::vector<unsigned char>>());
      return false;
      break;
    case OBJECT_TYPE: {
      obj.SetObject();
      Value::Object objMap = value.Get<Value::Object>();
      for (auto &it : objMap) {
        json elementJson;
        if (ValueToJson(it.second, &elementJson)) {
          obj.AddMember(json(it.first.c_str(), GetAllocator()),
                        std::move(elementJson), GetAllocator());
        }
      }
      break;
    }
    case NULL_TYPE:
    default:
      return false;
  }
#else
  switch (value.Type()) {
    case REAL_TYPE:
      obj = json(value.Get<double>());
      break;
    case INT_TYPE:
      obj = json(value.Get<int>());
      break;
    case BOOL_TYPE:
      obj = json(value.Get<bool>());
      break;
    case STRING_TYPE:
      obj = json(value.Get<std::string>());
      break;
    case ARRAY_TYPE: {
      for (unsigned int i = 0; i < value.ArrayLen(); ++i) {
        Value elementValue = value.Get(int(i));
        json elementJson;
        if (ValueToJson(value.Get(int(i)), &elementJson))
          obj.push_back(elementJson);
      }
      break;
    }
    case BINARY_TYPE:
      // TODO
      // obj = json(value.Get<std::vector<unsigned char>>());
      return false;
      break;
    case OBJECT_TYPE: {
      Value::Object objMap = value.Get<Value::Object>();
      for (auto &it : objMap) {
        json elementJson;
        if (ValueToJson(it.second, &elementJson)) obj[it.first] = elementJson;
      }
      break;
    }
    case NULL_TYPE:
    default:
      return false;
  }
#endif
  if (ret) *ret = std::move(obj);
  return true;
}

static void SerializeValue(const std::string &key, const Value &value,
                           json &obj) {
  json ret;
  if (ValueToJson(value, &ret)) {
    JsonAddMember(obj, key.c_str(), std::move(ret));
  }
}

static void SerializeGltfBufferData(const std::vector<unsigned char> &data,
                                    json &o) {
  std::string header = "data:application/octet-stream;base64,";
  if (data.size() > 0) {
    std::string encodedData =
        base64_encode(&data[0], static_cast<unsigned int>(data.size()));
    SerializeStringProperty("uri", header + encodedData, o);
  } else {
    // Issue #229
    // size 0 is allowd. Just emit mime header.
    SerializeStringProperty("uri", header, o);
  }
}

static bool SerializeGltfBufferData(const std::vector<unsigned char> &data,
                                    const std::string &binFilename) {
#ifdef _WIN32
#if defined(__GLIBCXX__)  // mingw
  int file_descriptor = _wopen(UTF8ToWchar(binFilename).c_str(),
                               _O_CREAT | _O_WRONLY | _O_TRUNC | _O_BINARY);
  __gnu_cxx::stdio_filebuf<char> wfile_buf(
      file_descriptor, std::ios_base::out | std::ios_base::binary);
  std::ostream output(&wfile_buf);
  if (!wfile_buf.is_open()) return false;
#elif defined(_MSC_VER)
  std::ofstream output(UTF8ToWchar(binFilename).c_str(), std::ofstream::binary);
  if (!output.is_open()) return false;
#else
  std::ofstream output(binFilename.c_str(), std::ofstream::binary);
  if (!output.is_open()) return false;
#endif
#else
  std::ofstream output(binFilename.c_str(), std::ofstream::binary);
  if (!output.is_open()) return false;
#endif
  if (data.size() > 0) {
    output.write(reinterpret_cast<const char *>(&data[0]),
                 std::streamsize(data.size()));
  } else {
    // Issue #229
    // size 0 will be still valid buffer data.
    // write empty file.
  }
  return true;
}

#if 0  // FIXME(syoyo): not used. will be removed in the future release.
static void SerializeParameterMap(ParameterMap &param, json &o) {
  for (ParameterMap::iterator paramIt = param.begin(); paramIt != param.end();
       ++paramIt) {
    if (paramIt->second.number_array.size()) {
      SerializeNumberArrayProperty<double>(paramIt->first,
                                           paramIt->second.number_array, o);
    } else if (paramIt->second.json_double_value.size()) {
      json json_double_value;
      for (std::map<std::string, double>::iterator it =
               paramIt->second.json_double_value.begin();
           it != paramIt->second.json_double_value.end(); ++it) {
        if (it->first == "index") {
          json_double_value[it->first] = paramIt->second.TextureIndex();
        } else {
          json_double_value[it->first] = it->second;
        }
      }

      o[paramIt->first] = json_double_value;
    } else if (!paramIt->second.string_value.empty()) {
      SerializeStringProperty(paramIt->first, paramIt->second.string_value, o);
    } else if (paramIt->second.has_number_value) {
      o[paramIt->first] = paramIt->second.number_value;
    } else {
      o[paramIt->first] = paramIt->second.bool_value;
    }
  }
}
#endif

static void SerializeExtensionMap(const ExtensionMap &extensions, json &o) {
  if (!extensions.size()) return;

  json extMap;
  for (ExtensionMap::const_iterator extIt = extensions.begin();
       extIt != extensions.end(); ++extIt) {
    // Allow an empty object for extension(#97)
    json ret;
    bool isNull = true;
    if (ValueToJson(extIt->second, &ret)) {
      isNull = JsonIsNull(ret);
      JsonAddMember(extMap, extIt->first.c_str(), std::move(ret));
    }
    if (isNull) {
      if (!(extIt->first.empty())) {  // name should not be empty, but for sure
        // create empty object so that an extension name is still included in
        // json.
        json empty;
        JsonSetObject(empty);
        JsonAddMember(extMap, extIt->first.c_str(), std::move(empty));
      }
    }
  }
  JsonAddMember(o, "extensions", std::move(extMap));
}

static void SerializeGltfAccessor(Accessor &accessor, json &o) {
  if (accessor.bufferView >= 0)
    SerializeNumberProperty<int>("bufferView", accessor.bufferView, o);

  if (accessor.byteOffset != 0)
    SerializeNumberProperty<int>("byteOffset", int(accessor.byteOffset), o);

  SerializeNumberProperty<int>("componentType", accessor.componentType, o);
  SerializeNumberProperty<size_t>("count", accessor.count, o);
  SerializeNumberArrayProperty<double>("min", accessor.minValues, o);
  SerializeNumberArrayProperty<double>("max", accessor.maxValues, o);
  if (accessor.normalized)
    SerializeValue("normalized", Value(accessor.normalized), o);
  std::string type;
  switch (accessor.type) {
    case TINYGLTF_TYPE_SCALAR:
      type = "SCALAR";
      break;
    case TINYGLTF_TYPE_VEC2:
      type = "VEC2";
      break;
    case TINYGLTF_TYPE_VEC3:
      type = "VEC3";
      break;
    case TINYGLTF_TYPE_VEC4:
      type = "VEC4";
      break;
    case TINYGLTF_TYPE_MAT2:
      type = "MAT2";
      break;
    case TINYGLTF_TYPE_MAT3:
      type = "MAT3";
      break;
    case TINYGLTF_TYPE_MAT4:
      type = "MAT4";
      break;
  }

  SerializeStringProperty("type", type, o);
  if (!accessor.name.empty()) SerializeStringProperty("name", accessor.name, o);

  if (accessor.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", accessor.extras, o);
  }
}

static void SerializeGltfAnimationChannel(AnimationChannel &channel, json &o) {
  SerializeNumberProperty("sampler", channel.sampler, o);
  {
    json target;
    SerializeNumberProperty("node", channel.target_node, target);
    SerializeStringProperty("path", channel.target_path, target);

    SerializeExtensionMap(channel.target_extensions, target);

    JsonAddMember(o, "target", std::move(target));
  }

  if (channel.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", channel.extras, o);
  }

  SerializeExtensionMap(channel.extensions, o);
}

static void SerializeGltfAnimationSampler(AnimationSampler &sampler, json &o) {
  SerializeNumberProperty("input", sampler.input, o);
  SerializeNumberProperty("output", sampler.output, o);
  SerializeStringProperty("interpolation", sampler.interpolation, o);

  if (sampler.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", sampler.extras, o);
  }
}

static void SerializeGltfAnimation(Animation &animation, json &o) {
  if (!animation.name.empty())
    SerializeStringProperty("name", animation.name, o);

  {
    json channels;
    JsonReserveArray(channels, animation.channels.size());
    for (unsigned int i = 0; i < animation.channels.size(); ++i) {
      json channel;
      AnimationChannel gltfChannel = animation.channels[i];
      SerializeGltfAnimationChannel(gltfChannel, channel);
      JsonPushBack(channels, std::move(channel));
    }

    JsonAddMember(o, "channels", std::move(channels));
  }

  {
    json samplers;
    JsonReserveArray(samplers, animation.samplers.size());
    for (unsigned int i = 0; i < animation.samplers.size(); ++i) {
      json sampler;
      AnimationSampler gltfSampler = animation.samplers[i];
      SerializeGltfAnimationSampler(gltfSampler, sampler);
      JsonPushBack(samplers, std::move(sampler));
    }
    JsonAddMember(o, "samplers", std::move(samplers));
  }

  if (animation.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", animation.extras, o);
  }

  SerializeExtensionMap(animation.extensions, o);
}

static void SerializeGltfAsset(Asset &asset, json &o) {
  if (!asset.generator.empty()) {
    SerializeStringProperty("generator", asset.generator, o);
  }

  if (!asset.copyright.empty()) {
    SerializeStringProperty("copyright", asset.copyright, o);
  }

  if (!asset.version.empty()) {
    SerializeStringProperty("version", asset.version, o);
  }

  if (asset.extras.Keys().size()) {
    SerializeValue("extras", asset.extras, o);
  }

  SerializeExtensionMap(asset.extensions, o);
}

static void SerializeGltfBufferBin(Buffer &buffer, json &o,
                                   std::vector<unsigned char> &binBuffer) {
  SerializeNumberProperty("byteLength", buffer.data.size(), o);
  binBuffer = buffer.data;

  if (buffer.name.size()) SerializeStringProperty("name", buffer.name, o);

  if (buffer.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", buffer.extras, o);
  }
}

static void SerializeGltfBuffer(Buffer &buffer, json &o) {
  SerializeNumberProperty("byteLength", buffer.data.size(), o);
  SerializeGltfBufferData(buffer.data, o);

  if (buffer.name.size()) SerializeStringProperty("name", buffer.name, o);

  if (buffer.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", buffer.extras, o);
  }
}

static bool SerializeGltfBuffer(Buffer &buffer, json &o,
                                const std::string &binFilename,
                                const std::string &binBaseFilename) {
  if (!SerializeGltfBufferData(buffer.data, binFilename)) return false;
  SerializeNumberProperty("byteLength", buffer.data.size(), o);
  SerializeStringProperty("uri", binBaseFilename, o);

  if (buffer.name.size()) SerializeStringProperty("name", buffer.name, o);

  if (buffer.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", buffer.extras, o);
  }
  return true;
}

static void SerializeGltfBufferView(BufferView &bufferView, json &o) {
  SerializeNumberProperty("buffer", bufferView.buffer, o);
  SerializeNumberProperty<size_t>("byteLength", bufferView.byteLength, o);

  // byteStride is optional, minimum allowed is 4
  if (bufferView.byteStride >= 4) {
    SerializeNumberProperty<size_t>("byteStride", bufferView.byteStride, o);
  }
  // byteOffset is optional, default is 0
  if (bufferView.byteOffset > 0) {
    SerializeNumberProperty<size_t>("byteOffset", bufferView.byteOffset, o);
  }
  // Target is optional, check if it contains a valid value
  if (bufferView.target == TINYGLTF_TARGET_ARRAY_BUFFER ||
      bufferView.target == TINYGLTF_TARGET_ELEMENT_ARRAY_BUFFER) {
    SerializeNumberProperty("target", bufferView.target, o);
  }
  if (bufferView.name.size()) {
    SerializeStringProperty("name", bufferView.name, o);
  }

  if (bufferView.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", bufferView.extras, o);
  }
}

static void SerializeGltfImage(Image &image, json &o) {
  // if uri empty, the mimeType and bufferview should be set
  if (image.uri.empty()) {
    SerializeStringProperty("mimeType", image.mimeType, o);
    SerializeNumberProperty<int>("bufferView", image.bufferView, o);
  } else {
    // TODO(syoyo): dlib::urilencode?
    SerializeStringProperty("uri", image.uri, o);
  }

  if (image.name.size()) {
    SerializeStringProperty("name", image.name, o);
  }

  if (image.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", image.extras, o);
  }

  SerializeExtensionMap(image.extensions, o);
}

static void SerializeGltfTextureInfo(TextureInfo &texinfo, json &o) {
  SerializeNumberProperty("index", texinfo.index, o);

  if (texinfo.texCoord != 0) {
    SerializeNumberProperty("texCoord", texinfo.texCoord, o);
  }

  if (texinfo.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", texinfo.extras, o);
  }

  SerializeExtensionMap(texinfo.extensions, o);
}

static void SerializeGltfNormalTextureInfo(NormalTextureInfo &texinfo,
                                           json &o) {
  SerializeNumberProperty("index", texinfo.index, o);

  if (texinfo.texCoord != 0) {
    SerializeNumberProperty("texCoord", texinfo.texCoord, o);
  }

  if (!TINYGLTF_DOUBLE_EQUAL(texinfo.scale, 1.0)) {
    SerializeNumberProperty("scale", texinfo.scale, o);
  }

  if (texinfo.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", texinfo.extras, o);
  }

  SerializeExtensionMap(texinfo.extensions, o);
}

static void SerializeGltfOcclusionTextureInfo(OcclusionTextureInfo &texinfo,
                                              json &o) {
  SerializeNumberProperty("index", texinfo.index, o);

  if (texinfo.texCoord != 0) {
    SerializeNumberProperty("texCoord", texinfo.texCoord, o);
  }

  if (!TINYGLTF_DOUBLE_EQUAL(texinfo.strength, 1.0)) {
    SerializeNumberProperty("strength", texinfo.strength, o);
  }

  if (texinfo.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", texinfo.extras, o);
  }

  SerializeExtensionMap(texinfo.extensions, o);
}

static void SerializeGltfPbrMetallicRoughness(PbrMetallicRoughness &pbr,
                                              json &o) {
  std::vector<double> default_baseColorFactor = {1.0, 1.0, 1.0, 1.0};
  if (!Equals(pbr.baseColorFactor, default_baseColorFactor)) {
    SerializeNumberArrayProperty<double>("baseColorFactor", pbr.baseColorFactor,
                                         o);
  }

  if (!TINYGLTF_DOUBLE_EQUAL(pbr.metallicFactor, 1.0)) {
    SerializeNumberProperty("metallicFactor", pbr.metallicFactor, o);
  }

  if (!TINYGLTF_DOUBLE_EQUAL(pbr.roughnessFactor, 1.0)) {
    SerializeNumberProperty("roughnessFactor", pbr.roughnessFactor, o);
  }

  if (pbr.baseColorTexture.index > -1) {
    json texinfo;
    SerializeGltfTextureInfo(pbr.baseColorTexture, texinfo);
    JsonAddMember(o, "baseColorTexture", std::move(texinfo));
  }

  if (pbr.metallicRoughnessTexture.index > -1) {
    json texinfo;
    SerializeGltfTextureInfo(pbr.metallicRoughnessTexture, texinfo);
    JsonAddMember(o, "metallicRoughnessTexture", std::move(texinfo));
  }

  SerializeExtensionMap(pbr.extensions, o);

  if (pbr.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", pbr.extras, o);
  }
}

static void SerializeGltfMaterial(Material &material, json &o) {
  if (material.name.size()) {
    SerializeStringProperty("name", material.name, o);
  }

  // QUESTION(syoyo): Write material parameters regardless of its default value?

  if (!TINYGLTF_DOUBLE_EQUAL(material.alphaCutoff, 0.5)) {
    SerializeNumberProperty("alphaCutoff", material.alphaCutoff, o);
  }

  if (material.alphaMode.compare("OPAQUE") != 0) {
    SerializeStringProperty("alphaMode", material.alphaMode, o);
  }

  if (material.doubleSided != false)
    JsonAddMember(o, "doubleSided", json(material.doubleSided));

  if (material.normalTexture.index > -1) {
    json texinfo;
    SerializeGltfNormalTextureInfo(material.normalTexture, texinfo);
    JsonAddMember(o, "normalTexture", std::move(texinfo));
  }

  if (material.occlusionTexture.index > -1) {
    json texinfo;
    SerializeGltfOcclusionTextureInfo(material.occlusionTexture, texinfo);
    JsonAddMember(o, "occlusionTexture", std::move(texinfo));
  }

  if (material.emissiveTexture.index > -1) {
    json texinfo;
    SerializeGltfTextureInfo(material.emissiveTexture, texinfo);
    JsonAddMember(o, "emissiveTexture", std::move(texinfo));
  }

  std::vector<double> default_emissiveFactor = {0.0, 0.0, 0.0};
  if (!Equals(material.emissiveFactor, default_emissiveFactor)) {
    SerializeNumberArrayProperty<double>("emissiveFactor",
                                         material.emissiveFactor, o);
  }

  {
    json pbrMetallicRoughness;
    SerializeGltfPbrMetallicRoughness(material.pbrMetallicRoughness,
                                      pbrMetallicRoughness);
    // Issue 204
    // Do not serialize `pbrMetallicRoughness` if pbrMetallicRoughness has all
    // default values(json is null). Otherwise it will serialize to
    // `pbrMetallicRoughness : null`, which cannot be read by other glTF
    // importers(and validators).
    //
    if (!JsonIsNull(pbrMetallicRoughness)) {
      JsonAddMember(o, "pbrMetallicRoughness", std::move(pbrMetallicRoughness));
    }
  }

#if 0  // legacy way. just for the record.
  if (material.values.size()) {
    json pbrMetallicRoughness;
    SerializeParameterMap(material.values, pbrMetallicRoughness);
    JsonAddMember(o, "pbrMetallicRoughness", std::move(pbrMetallicRoughness));
  }

  SerializeParameterMap(material.additionalValues, o);
#else

#endif

  SerializeExtensionMap(material.extensions, o);

  if (material.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", material.extras, o);
  }
}

static void SerializeGltfMesh(Mesh &mesh, json &o) {
  json primitives;
  JsonReserveArray(primitives, mesh.primitives.size());
  for (unsigned int i = 0; i < mesh.primitives.size(); ++i) {
    json primitive;
    const Primitive &gltfPrimitive = mesh.primitives[i];  // don't make a copy
    {
      json attributes;
      for (auto attrIt = gltfPrimitive.attributes.begin();
           attrIt != gltfPrimitive.attributes.end(); ++attrIt) {
        SerializeNumberProperty<int>(attrIt->first, attrIt->second, attributes);
      }

      JsonAddMember(primitive, "attributes", std::move(attributes));
    }

    // Indicies is optional
    if (gltfPrimitive.indices > -1) {
      SerializeNumberProperty<int>("indices", gltfPrimitive.indices, primitive);
    }
    // Material is optional
    if (gltfPrimitive.material > -1) {
      SerializeNumberProperty<int>("material", gltfPrimitive.material,
                                   primitive);
    }
    SerializeNumberProperty<int>("mode", gltfPrimitive.mode, primitive);

    // Morph targets
    if (gltfPrimitive.targets.size()) {
      json targets;
      JsonReserveArray(targets, gltfPrimitive.targets.size());
      for (unsigned int k = 0; k < gltfPrimitive.targets.size(); ++k) {
        json targetAttributes;
        std::map<std::string, int> targetData = gltfPrimitive.targets[k];
        for (std::map<std::string, int>::iterator attrIt = targetData.begin();
             attrIt != targetData.end(); ++attrIt) {
          SerializeNumberProperty<int>(attrIt->first, attrIt->second,
                                       targetAttributes);
        }
        JsonPushBack(targets, std::move(targetAttributes));
      }
      JsonAddMember(primitive, "targets", std::move(targets));
    }

    SerializeExtensionMap(gltfPrimitive.extensions, primitive);

    if (gltfPrimitive.extras.Type() != NULL_TYPE) {
      SerializeValue("extras", gltfPrimitive.extras, primitive);
    }

    JsonPushBack(primitives, std::move(primitive));
  }

  JsonAddMember(o, "primitives", std::move(primitives));

  if (mesh.weights.size()) {
    SerializeNumberArrayProperty<double>("weights", mesh.weights, o);
  }

  if (mesh.name.size()) {
    SerializeStringProperty("name", mesh.name, o);
  }

  SerializeExtensionMap(mesh.extensions, o);
  if (mesh.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", mesh.extras, o);
  }
}

static void SerializeSpotLight(SpotLight &spot, json &o) {
  SerializeNumberProperty("innerConeAngle", spot.innerConeAngle, o);
  SerializeNumberProperty("outerConeAngle", spot.outerConeAngle, o);
  SerializeExtensionMap(spot.extensions, o);
  if (spot.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", spot.extras, o);
  }
}

static void SerializeGltfLight(Light &light, json &o) {
  if (!light.name.empty()) SerializeStringProperty("name", light.name, o);
  SerializeNumberProperty("intensity", light.intensity, o);
  if (light.range > 0.0) {
    SerializeNumberProperty("range", light.range, o);
  }
  SerializeNumberArrayProperty("color", light.color, o);
  SerializeStringProperty("type", light.type, o);
  if (light.type == "spot") {
    json spot;
    SerializeSpotLight(light.spot, spot);
    JsonAddMember(o, "spot", std::move(spot));
  }
  SerializeExtensionMap(light.extensions, o);
  if (light.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", light.extras, o);
  }
}

static void SerializeGltfNode(Node &node, json &o) {
  if (node.translation.size() > 0) {
    SerializeNumberArrayProperty<double>("translation", node.translation, o);
  }
  if (node.rotation.size() > 0) {
    SerializeNumberArrayProperty<double>("rotation", node.rotation, o);
  }
  if (node.scale.size() > 0) {
    SerializeNumberArrayProperty<double>("scale", node.scale, o);
  }
  if (node.matrix.size() > 0) {
    SerializeNumberArrayProperty<double>("matrix", node.matrix, o);
  }
  if (node.mesh != -1) {
    SerializeNumberProperty<int>("mesh", node.mesh, o);
  }

  if (node.skin != -1) {
    SerializeNumberProperty<int>("skin", node.skin, o);
  }

  if (node.camera != -1) {
    SerializeNumberProperty<int>("camera", node.camera, o);
  }

  if (node.weights.size() > 0) {
    SerializeNumberArrayProperty<double>("weights", node.weights, o);
  }

  if (node.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", node.extras, o);
  }

  SerializeExtensionMap(node.extensions, o);
  if (!node.name.empty()) SerializeStringProperty("name", node.name, o);
  SerializeNumberArrayProperty<int>("children", node.children, o);
}

static void SerializeGltfSampler(Sampler &sampler, json &o) {
  if (sampler.magFilter != -1) {
    SerializeNumberProperty("magFilter", sampler.magFilter, o);
  }
  if (sampler.minFilter != -1) {
    SerializeNumberProperty("minFilter", sampler.minFilter, o);
  }
  SerializeNumberProperty("wrapR", sampler.wrapR, o);
  SerializeNumberProperty("wrapS", sampler.wrapS, o);
  SerializeNumberProperty("wrapT", sampler.wrapT, o);

  if (sampler.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", sampler.extras, o);
  }
}

static void SerializeGltfOrthographicCamera(const OrthographicCamera &camera,
                                            json &o) {
  SerializeNumberProperty("zfar", camera.zfar, o);
  SerializeNumberProperty("znear", camera.znear, o);
  SerializeNumberProperty("xmag", camera.xmag, o);
  SerializeNumberProperty("ymag", camera.ymag, o);

  if (camera.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", camera.extras, o);
  }
}

static void SerializeGltfPerspectiveCamera(const PerspectiveCamera &camera,
                                           json &o) {
  SerializeNumberProperty("zfar", camera.zfar, o);
  SerializeNumberProperty("znear", camera.znear, o);
  if (camera.aspectRatio > 0) {
    SerializeNumberProperty("aspectRatio", camera.aspectRatio, o);
  }

  if (camera.yfov > 0) {
    SerializeNumberProperty("yfov", camera.yfov, o);
  }

  if (camera.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", camera.extras, o);
  }
}

static void SerializeGltfCamera(const Camera &camera, json &o) {
  SerializeStringProperty("type", camera.type, o);
  if (!camera.name.empty()) {
    SerializeStringProperty("name", camera.name, o);
  }

  if (camera.type.compare("orthographic") == 0) {
    json orthographic;
    SerializeGltfOrthographicCamera(camera.orthographic, orthographic);
    JsonAddMember(o, "orthographic", std::move(orthographic));
  } else if (camera.type.compare("perspective") == 0) {
    json perspective;
    SerializeGltfPerspectiveCamera(camera.perspective, perspective);
    JsonAddMember(o, "perspective", std::move(perspective));
  } else {
    // ???
  }

  if (camera.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", camera.extras, o);
  }
  SerializeExtensionMap(camera.extensions, o);
}

static void SerializeGltfScene(Scene &scene, json &o) {
  SerializeNumberArrayProperty<int>("nodes", scene.nodes, o);

  if (scene.name.size()) {
    SerializeStringProperty("name", scene.name, o);
  }
  if (scene.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", scene.extras, o);
  }
  SerializeExtensionMap(scene.extensions, o);
}

static void SerializeGltfSkin(Skin &skin, json &o) {
  if (skin.inverseBindMatrices != -1)
    SerializeNumberProperty("inverseBindMatrices", skin.inverseBindMatrices, o);

  SerializeNumberArrayProperty<int>("joints", skin.joints, o);
  SerializeNumberProperty("skeleton", skin.skeleton, o);
  if (skin.name.size()) {
    SerializeStringProperty("name", skin.name, o);
  }
}

static void SerializeGltfTexture(Texture &texture, json &o) {
  if (texture.sampler > -1) {
    SerializeNumberProperty("sampler", texture.sampler, o);
  }
  if (texture.source > -1) {
    SerializeNumberProperty("source", texture.source, o);
  }
  if (texture.name.size()) {
    SerializeStringProperty("name", texture.name, o);
  }
  if (texture.extras.Type() != NULL_TYPE) {
    SerializeValue("extras", texture.extras, o);
  }
  SerializeExtensionMap(texture.extensions, o);
}

///
/// Serialize all properties except buffers and images.
///
static void SerializeGltfModel(Model *model, json &o) {
  // ACCESSORS
  if (model->accessors.size()) {
    json accessors;
    JsonReserveArray(accessors, model->accessors.size());
    for (unsigned int i = 0; i < model->accessors.size(); ++i) {
      json accessor;
      SerializeGltfAccessor(model->accessors[i], accessor);
      JsonPushBack(accessors, std::move(accessor));
    }
    JsonAddMember(o, "accessors", std::move(accessors));
  }

  // ANIMATIONS
  if (model->animations.size()) {
    json animations;
    JsonReserveArray(animations, model->animations.size());
    for (unsigned int i = 0; i < model->animations.size(); ++i) {
      if (model->animations[i].channels.size()) {
        json animation;
        SerializeGltfAnimation(model->animations[i], animation);
        JsonPushBack(animations, std::move(animation));
      }
    }

    JsonAddMember(o, "animations", std::move(animations));
  }

  // ASSET
  json asset;
  SerializeGltfAsset(model->asset, asset);
  JsonAddMember(o, "asset", std::move(asset));

  // BUFFERVIEWS
  if (model->bufferViews.size()) {
    json bufferViews;
    JsonReserveArray(bufferViews, model->bufferViews.size());
    for (unsigned int i = 0; i < model->bufferViews.size(); ++i) {
      json bufferView;
      SerializeGltfBufferView(model->bufferViews[i], bufferView);
      JsonPushBack(bufferViews, std::move(bufferView));
    }
    JsonAddMember(o, "bufferViews", std::move(bufferViews));
  }

  // Extensions required
  if (model->extensionsRequired.size()) {
    SerializeStringArrayProperty("extensionsRequired",
                                 model->extensionsRequired, o);
  }

  // MATERIALS
  if (model->materials.size()) {
    json materials;
    JsonReserveArray(materials, model->materials.size());
    for (unsigned int i = 0; i < model->materials.size(); ++i) {
      json material;
      SerializeGltfMaterial(model->materials[i], material);
      JsonPushBack(materials, std::move(material));
    }
    JsonAddMember(o, "materials", std::move(materials));
  }

  // MESHES
  if (model->meshes.size()) {
    json meshes;
    JsonReserveArray(meshes, model->meshes.size());
    for (unsigned int i = 0; i < model->meshes.size(); ++i) {
      json mesh;
      SerializeGltfMesh(model->meshes[i], mesh);
      JsonPushBack(meshes, std::move(mesh));
    }
    JsonAddMember(o, "meshes", std::move(meshes));
  }

  // NODES
  if (model->nodes.size()) {
    json nodes;
    JsonReserveArray(nodes, model->nodes.size());
    for (unsigned int i = 0; i < model->nodes.size(); ++i) {
      json node;
      SerializeGltfNode(model->nodes[i], node);
      JsonPushBack(nodes, std::move(node));
    }
    JsonAddMember(o, "nodes", std::move(nodes));
  }

  // SCENE
  if (model->defaultScene > -1) {
    SerializeNumberProperty<int>("scene", model->defaultScene, o);
  }

  // SCENES
  if (model->scenes.size()) {
    json scenes;
    JsonReserveArray(scenes, model->scenes.size());
    for (unsigned int i = 0; i < model->scenes.size(); ++i) {
      json currentScene;
      SerializeGltfScene(model->scenes[i], currentScene);
      JsonPushBack(scenes, std::move(currentScene));
    }
    JsonAddMember(o, "scenes", std::move(scenes));
  }

  // SKINS
  if (model->skins.size()) {
    json skins;
    JsonReserveArray(skins, model->skins.size());
    for (unsigned int i = 0; i < model->skins.size(); ++i) {
      json skin;
      SerializeGltfSkin(model->skins[i], skin);
      JsonPushBack(skins, std::move(skin));
    }
    JsonAddMember(o, "skins", std::move(skins));
  }

  // TEXTURES
  if (model->textures.size()) {
    json textures;
    JsonReserveArray(textures, model->textures.size());
    for (unsigned int i = 0; i < model->textures.size(); ++i) {
      json texture;
      SerializeGltfTexture(model->textures[i], texture);
      JsonPushBack(textures, std::move(texture));
    }
    JsonAddMember(o, "textures", std::move(textures));
  }

  // SAMPLERS
  if (model->samplers.size()) {
    json samplers;
    JsonReserveArray(samplers, model->samplers.size());
    for (unsigned int i = 0; i < model->samplers.size(); ++i) {
      json sampler;
      SerializeGltfSampler(model->samplers[i], sampler);
      JsonPushBack(samplers, std::move(sampler));
    }
    JsonAddMember(o, "samplers", std::move(samplers));
  }

  // CAMERAS
  if (model->cameras.size()) {
    json cameras;
    JsonReserveArray(cameras, model->cameras.size());
    for (unsigned int i = 0; i < model->cameras.size(); ++i) {
      json camera;
      SerializeGltfCamera(model->cameras[i], camera);
      JsonPushBack(cameras, std::move(camera));
    }
    JsonAddMember(o, "cameras", std::move(cameras));
  }

  // EXTENSIONS
  SerializeExtensionMap(model->extensions, o);

  auto extensionsUsed = model->extensionsUsed;

  // LIGHTS as KHR_lights_punctual
  if (model->lights.size()) {
    json lights;
    JsonReserveArray(lights, model->lights.size());
    for (unsigned int i = 0; i < model->lights.size(); ++i) {
      json light;
      SerializeGltfLight(model->lights[i], light);
      JsonPushBack(lights, std::move(light));
    }
    json khr_lights_cmn;
    JsonAddMember(khr_lights_cmn, "lights", std::move(lights));
    json ext_j;

    {
      json_const_iterator it;
      if (FindMember(o, "extensions", it)) {
        JsonAssign(ext_j, GetValue(it));
      }
    }

    JsonAddMember(ext_j, "KHR_lights_punctual", std::move(khr_lights_cmn));

    JsonAddMember(o, "extensions", std::move(ext_j));

    // Also add "KHR_lights_punctual" to `extensionsUsed`
    {
      auto has_khr_lights_punctual = std::find_if(
          extensionsUsed.begin(), extensionsUsed.end(), [](const std::string &s) {
                         return (s.compare("KHR_lights_punctual") == 0);
                       });

      if (has_khr_lights_punctual == extensionsUsed.end()) {
        extensionsUsed.push_back("KHR_lights_punctual");
      }
    }
  }

  // Extensions used
  if (model->extensionsUsed.size()) {
    SerializeStringArrayProperty("extensionsUsed", extensionsUsed, o);
  }

  // EXTRAS
  if (model->extras.Type() != NULL_TYPE) {
    SerializeValue("extras", model->extras, o);
  }
}

static bool WriteGltfStream(std::ostream &stream, const std::string &content) {
  stream << content << std::endl;
  return true;
}

static bool WriteGltfFile(const std::string &output,
                          const std::string &content) {
#ifdef _WIN32
#if defined(_MSC_VER)
  std::ofstream gltfFile(UTF8ToWchar(output).c_str());
#elif defined(__GLIBCXX__)
  int file_descriptor = _wopen(UTF8ToWchar(output).c_str(),
                               _O_CREAT | _O_WRONLY | _O_TRUNC | _O_BINARY);
  __gnu_cxx::stdio_filebuf<char> wfile_buf(
      file_descriptor, std::ios_base::out | std::ios_base::binary);
  std::ostream gltfFile(&wfile_buf);
  if (!wfile_buf.is_open()) return false;
#else
  std::ofstream gltfFile(output.c_str());
  if (!gltfFile.is_open()) return false;
#endif
#else
  std::ofstream gltfFile(output.c_str());
  if (!gltfFile.is_open()) return false;
#endif
  return WriteGltfStream(gltfFile, content);
}

static void WriteBinaryGltfStream(std::ostream &stream,
                                  const std::string &content,
                                  const std::vector<unsigned char> &binBuffer) {
  const std::string header = "glTF";
  const int version = 2;

  // https://stackoverflow.com/questions/3407012/c-rounding-up-to-the-nearest-multiple-of-a-number
  auto roundUp = [](uint32_t numToRound, uint32_t multiple) {
    if (multiple == 0) return numToRound;

    uint32_t remainder = numToRound % multiple;
    if (remainder == 0) return numToRound;

    return numToRound + multiple - remainder;
  };

  const uint32_t padding_size =
      roundUp(uint32_t(content.size()), 4) - uint32_t(content.size());

  // 12 bytes for header, JSON content length, 8 bytes for JSON chunk info.
  // Chunk data must be located at 4-byte boundary.
  const uint32_t length =
      12 + 8 + roundUp(uint32_t(content.size()), 4) +
      (binBuffer.size() ? (8 + roundUp(uint32_t(binBuffer.size()), 4)) : 0);

  stream.write(header.c_str(), std::streamsize(header.size()));
  stream.write(reinterpret_cast<const char *>(&version), sizeof(version));
  stream.write(reinterpret_cast<const char *>(&length), sizeof(length));

  // JSON chunk info, then JSON data
  const uint32_t model_length = uint32_t(content.size()) + padding_size;
  const uint32_t model_format = 0x4E4F534A;
  stream.write(reinterpret_cast<const char *>(&model_length),
               sizeof(model_length));
  stream.write(reinterpret_cast<const char *>(&model_format),
               sizeof(model_format));
  stream.write(content.c_str(), std::streamsize(content.size()));

  // Chunk must be multiplies of 4, so pad with spaces
  if (padding_size > 0) {
    const std::string padding = std::string(size_t(padding_size), ' ');
    stream.write(padding.c_str(), std::streamsize(padding.size()));
  }
  if (binBuffer.size() > 0) {
    const uint32_t bin_padding_size =
        roundUp(uint32_t(binBuffer.size()), 4) - uint32_t(binBuffer.size());
    // BIN chunk info, then BIN data
    const uint32_t bin_length = uint32_t(binBuffer.size()) + bin_padding_size;
    const uint32_t bin_format = 0x004e4942;
    stream.write(reinterpret_cast<const char *>(&bin_length),
                 sizeof(bin_length));
    stream.write(reinterpret_cast<const char *>(&bin_format),
                 sizeof(bin_format));
    stream.write(reinterpret_cast<const char *>(binBuffer.data()),
                 std::streamsize(binBuffer.size()));
    // Chunksize must be multiplies of 4, so pad with zeroes
    if (bin_padding_size > 0) {
      const std::vector<unsigned char> padding =
          std::vector<unsigned char>(size_t(bin_padding_size), 0);
      stream.write(reinterpret_cast<const char *>(padding.data()),
                   std::streamsize(padding.size()));
    }
  }
}

static void WriteBinaryGltfFile(const std::string &output,
                                const std::string &content,
                                const std::vector<unsigned char> &binBuffer) {
#ifdef _WIN32
#if defined(_MSC_VER)
  std::ofstream gltfFile(UTF8ToWchar(output).c_str(), std::ios::binary);
#elif defined(__GLIBCXX__)
  int file_descriptor = _wopen(UTF8ToWchar(output).c_str(),
                               _O_CREAT | _O_WRONLY | _O_TRUNC | _O_BINARY);
  __gnu_cxx::stdio_filebuf<char> wfile_buf(
      file_descriptor, std::ios_base::out | std::ios_base::binary);
  std::ostream gltfFile(&wfile_buf);
#else
  std::ofstream gltfFile(output.c_str(), std::ios::binary);
#endif
#else
  std::ofstream gltfFile(output.c_str(), std::ios::binary);
#endif
  WriteBinaryGltfStream(gltfFile, content, binBuffer);
}

bool TinyGLTF::WriteGltfSceneToStream(Model *model, std::ostream &stream,
                                      bool prettyPrint = true,
                                      bool writeBinary = false) {
  JsonDocument output;

  /// Serialize all properties except buffers and images.
  SerializeGltfModel(model, output);

  // BUFFERS
  std::vector<unsigned char> binBuffer;
  if (model->buffers.size()) {
    json buffers;
    JsonReserveArray(buffers, model->buffers.size());
    for (unsigned int i = 0; i < model->buffers.size(); ++i) {
      json buffer;
      if (writeBinary && i == 0 && model->buffers[i].uri.empty()) {
        SerializeGltfBufferBin(model->buffers[i], buffer, binBuffer);
      } else {
        SerializeGltfBuffer(model->buffers[i], buffer);
      }
      JsonPushBack(buffers, std::move(buffer));
    }
    JsonAddMember(output, "buffers", std::move(buffers));
  }

  // IMAGES
  if (model->images.size()) {
    json images;
    JsonReserveArray(images, model->images.size());
    for (unsigned int i = 0; i < model->images.size(); ++i) {
      json image;

      std::string dummystring = "";
      // UpdateImageObject need baseDir but only uses it if embeddedImages is
      // enabled, since we won't write separate images when writing to a stream
      // we
      UpdateImageObject(model->images[i], dummystring, int(i), false,
                        &this->WriteImageData, this->write_image_user_data_);
      SerializeGltfImage(model->images[i], image);
      JsonPushBack(images, std::move(image));
    }
    JsonAddMember(output, "images", std::move(images));
  }

  if (writeBinary) {
    WriteBinaryGltfStream(stream, JsonToString(output), binBuffer);
  } else {
    WriteGltfStream(stream, JsonToString(output, prettyPrint ? 2 : -1));
  }

  return true;
}

bool TinyGLTF::WriteGltfSceneToFile(Model *model, const std::string &filename,
                                    bool embedImages = false,
                                    bool embedBuffers = false,
                                    bool prettyPrint = true,
                                    bool writeBinary = false) {
  JsonDocument output;
  std::string defaultBinFilename = GetBaseFilename(filename);
  std::string defaultBinFileExt = ".bin";
  std::string::size_type pos =
      defaultBinFilename.rfind('.', defaultBinFilename.length());

  if (pos != std::string::npos) {
    defaultBinFilename = defaultBinFilename.substr(0, pos);
  }
  std::string baseDir = GetBaseDir(filename);
  if (baseDir.empty()) {
    baseDir = "./";
  }
  /// Serialize all properties except buffers and images.
  SerializeGltfModel(model, output);

  // BUFFERS
  std::vector<std::string> usedUris;
  std::vector<unsigned char> binBuffer;
  if (model->buffers.size()) {
    json buffers;
    JsonReserveArray(buffers, model->buffers.size());
    for (unsigned int i = 0; i < model->buffers.size(); ++i) {
      json buffer;
      if (writeBinary && i == 0 && model->buffers[i].uri.empty()) {
        SerializeGltfBufferBin(model->buffers[i], buffer, binBuffer);
      } else if (embedBuffers) {
        SerializeGltfBuffer(model->buffers[i], buffer);
      } else {
        std::string binSavePath;
        std::string binUri;
        if (!model->buffers[i].uri.empty() &&
            !IsDataURI(model->buffers[i].uri)) {
          binUri = model->buffers[i].uri;
        } else {
          binUri = defaultBinFilename + defaultBinFileExt;
          bool inUse = true;
          int numUsed = 0;
          while (inUse) {
            inUse = false;
            for (const std::string &usedName : usedUris) {
              if (binUri.compare(usedName) != 0) continue;
              inUse = true;
              binUri = defaultBinFilename + std::to_string(numUsed++) +
                       defaultBinFileExt;
              break;
            }
          }
        }
        usedUris.push_back(binUri);
        binSavePath = JoinPath(baseDir, binUri);
        if (!SerializeGltfBuffer(model->buffers[i], buffer, binSavePath,
                                 binUri)) {
          return false;
        }
      }
      JsonPushBack(buffers, std::move(buffer));
    }
    JsonAddMember(output, "buffers", std::move(buffers));
  }

  // IMAGES
  if (model->images.size()) {
    json images;
    JsonReserveArray(images, model->images.size());
    for (unsigned int i = 0; i < model->images.size(); ++i) {
      json image;

      UpdateImageObject(model->images[i], baseDir, int(i), embedImages,
                        &this->WriteImageData, this->write_image_user_data_);
      SerializeGltfImage(model->images[i], image);
      JsonPushBack(images, std::move(image));
    }
    JsonAddMember(output, "images", std::move(images));
  }

  if (writeBinary) {
    WriteBinaryGltfFile(filename, JsonToString(output), binBuffer);
  } else {
    WriteGltfFile(filename, JsonToString(output, (prettyPrint ? 2 : -1)));
  }

  return true;
}

}  // namespace tinygltf

#ifdef __clang__
#pragma clang diagnostic pop
#endif