ccls/src/serializer.h

#pragma once

#include <macro_map.h>
#include <optional.h>
#include <rapidjson/document.h>
#include <rapidjson/prettywriter.h>

#include <memory>
#include <string>
#include <vector>

using std::experimental::nullopt;
using std::experimental::optional;

using Reader = rapidjson::GenericValue<rapidjson::UTF8<>>;
using Writer = rapidjson::Writer<rapidjson::StringBuffer>;
struct IndexFile;

#define REFLECT_MEMBER_START()             \
  if (!ReflectMemberStart(visitor, value)) \
  return
#define REFLECT_MEMBER_START1(value)       \
  if (!ReflectMemberStart(visitor, value)) \
  return
#define REFLECT_MEMBER_END() ReflectMemberEnd(visitor, value);
#define REFLECT_MEMBER_END1(value) ReflectMemberEnd(visitor, value);
#define REFLECT_MEMBER(name) ReflectMember(visitor, #name, value.name)
#define REFLECT_MEMBER2(name, value) ReflectMember(visitor, name, value)

#define MAKE_REFLECT_TYPE_PROXY(type, as_type)   \
  template <typename TVisitor>                   \
  void Reflect(TVisitor& visitor, type& value) { \
    auto value0 = static_cast<as_type>(value);   \
    Reflect(visitor, value0);                    \
    value = static_cast<type>(value0);           \
  }

#define _MAPPABLE_REFLECT_MEMBER(name) REFLECT_MEMBER(name);

#define MAKE_REFLECT_EMPTY_STRUCT(type, ...)     \
  template <typename TVisitor>                   \
  void Reflect(TVisitor& visitor, type& value) { \
    REFLECT_MEMBER_START();                      \
    REFLECT_MEMBER_END();                        \
  }

#define MAKE_REFLECT_STRUCT(type, ...)               \
  template <typename TVisitor>                       \
  void Reflect(TVisitor& visitor, type& value) {     \
    REFLECT_MEMBER_START();                          \
    MACRO_MAP(_MAPPABLE_REFLECT_MEMBER, __VA_ARGS__) \
    REFLECT_MEMBER_END();                            \
  }

#define _MAPPABLE_REFLECT_ARRAY(name) Reflect(visitor, value.name);

// Reflects the struct so it is serialized as an array instead of an object.
// This currently only supports writers.
#define MAKE_REFLECT_STRUCT_WRITER_AS_ARRAY(type, ...) \
  inline void Reflect(Writer& visitor, type& value) {  \
    visitor.StartArray();                              \
    MACRO_MAP(_MAPPABLE_REFLECT_ARRAY, __VA_ARGS__)    \
    visitor.EndArray();                                \
  }

template <typename T>
struct NonElidedVector : public std::vector<T> {};

// API:
/*
template<typename TVisitor, typename T>
void Reflect(TVisitor& visitor, T& value) {
  static_assert(false, "Missing implementation");
}
template<typename TVisitor>
void DefaultReflectMemberStart(TVisitor& visitor) {
  static_assert(false, "Missing implementation");
}
template<typename TVisitor, typename T>
bool ReflectMemberStart(TVisitor& visitor, T& value) {
  static_assert(false, "Missing implementation");
  return true;
}
template<typename TVisitor, typename T>
void ReflectMemberEnd(TVisitor& visitor, T& value) {
  static_assert(false, "Missing implementation");
}
*/

// int16_t
void Reflect(Reader& visitor, int16_t& value);
void Reflect(Writer& visitor, int16_t& value);
// int32_t
void Reflect(Reader& visitor, int32_t& value);
void Reflect(Writer& visitor, int32_t& value);
// int64_t
void Reflect(Reader& visitor, int64_t& value);
void Reflect(Writer& visitor, int64_t& value);
// uint64_t
void Reflect(Reader& visitor, uint64_t& value);
void Reflect(Writer& visitor, uint64_t& value);
// bool
void Reflect(Reader& visitor, bool& value);
void Reflect(Writer& visitor, bool& value);
// std::string
void Reflect(Reader& visitor, std::string& value);
void Reflect(Writer& visitor, std::string& value);

// Writer:
template <typename T>
void Reflect(Writer& visitor, std::vector<T>& values) {
  visitor.StartArray();
  for (auto& value : values)
    Reflect(visitor, value);
  visitor.EndArray();
}
template <typename T>
void Reflect(Writer& visitor, optional<T> value) {
  if (value)
    Reflect(visitor, value.value());
}
inline void DefaultReflectMemberStart(Writer& visitor) {
  visitor.StartObject();
}
template <typename T>
bool ReflectMemberStart(Writer& visitor, T& value) {
  visitor.StartObject();
  return true;
}
template <typename T>
void ReflectMemberEnd(Writer& visitor, T& value) {
  visitor.EndObject();
}
template <typename T>
void ReflectMember(Writer& visitor, const char* name, T& value) {
  visitor.Key(name);
  Reflect(visitor, value);
}
template <typename T>
void ReflectMember(Writer& visitor, const char* name, std::vector<T>& values) {
  if (values.empty())
    return;
  visitor.Key(name);
  visitor.StartArray();
  for (auto& value : values)
    Reflect(visitor, value);
  visitor.EndArray();
}
template <typename T>
void ReflectMember(Writer& visitor,
                   const char* name,
                   NonElidedVector<T>& values) {
  visitor.Key(name);
  visitor.StartArray();
  for (auto& value : values)
    Reflect(visitor, value);
  visitor.EndArray();
}
template <typename T>
void ReflectMember(Writer& visitor, const char* name, optional<T>& value) {
  if (!value)
    return;
  visitor.Key(name);
  Reflect(visitor, value);
}
void ReflectMember(Writer& visitor, const char* name, std::string& value);

// Reader:
template <typename T>
void Reflect(Reader& visitor, std::vector<T>& values) {
  if (!visitor.IsArray())
    return;
  for (auto& entry : visitor.GetArray()) {
    T entry_value;
    Reflect(entry, entry_value);
    values.push_back(entry_value);
  }
}
template <typename T>
void Reflect(Reader& visitor, optional<T>& value) {
  if (visitor.IsNull())
    return;
  T real_value;
  Reflect(visitor, real_value);
  value = real_value;
}
inline void DefaultReflectMemberStart(Reader& visitor) {}
template <typename T>
bool ReflectMemberStart(Reader& visitor, T& value) {
  return true;
}
template <typename T>
void ReflectMemberEnd(Reader& visitor, T& value) {}
template <typename T>
void ReflectMember(Reader& visitor, const char* name, T& value) {
  auto it = visitor.FindMember(name);
  if (it != visitor.MemberEnd()) {
    Reader& child_visitor = it->value;
    Reflect(child_visitor, value);
  }
}

std::string Serialize(IndexFile& file);
std::unique_ptr<IndexFile> Deserialize(std::string path,
                                       std::string serialized,
                                       optional<int> expected_version);

void SetTestOutputMode();