forstio/source/forstio/message.h

563 lines
14 KiB
C++

#pragma once
#include <cstdint>
#include <tuple>
#include <type_traits>
#include <variant>
#include <vector>
#include <cassert>
#include "common.h"
#include "message_container.h"
#include "schema.h"
#include "string_literal.h"
namespace saw {
class message_base {
protected:
bool set_explicitly_ = false;
public:
template <class T> T &as() {
static_assert(std::is_base_of<message_base, T>());
return dynamic_cast<T &>(*this);
}
template <class T> const T &as() const {
static_assert(std::is_base_of<message_base, T>());
return dynamic_cast<const T &>(*this);
}
};
/*
* Representing all message types
* Description which type to use happens through the use of the schema classes
* in schema.h The message classes are wrapper classes which store the data
* according to the specified container class.
*
* The reader and builder classe exist to create some clarity while implementing
* parsers. Also minor guarantess are provided if the message is used as a
* template parameter.
*/
/*
* Struct Message
*/
template <class... V, string_literal... Keys, class Container>
class message<schema::Struct<schema::NamedMember<V, Keys>...>, Container> final
: public message_base {
private:
using SchemaType = schema::Struct<schema::NamedMember<V, Keys>...>;
using MessageType = message<SchemaType, Container>;
Container container_;
static_assert(std::is_same_v<SchemaType, typename Container::SchemaType>,
"Container should have same the schema as Message");
friend class builder;
friend class reader;
public:
class reader;
class builder {
private:
MessageType &message_;
public:
builder(MessageType &msg) : message_{msg} {}
reader as_reader() { return reader{message_}; }
/*
* Initialize a member by index
*/
template <size_t i>
typename std::enable_if<
!SchemaIsArray<
typename MessageParameterPackType<i, V...>::Type>::Value,
typename Container::template ElementType<i>::builder>::type
init() {
return typename Container::template ElementType<i>::builder{
message_.container_.template get<i>()};
}
/*
* Initialize a member by their name
* This is the preferred method for schema::Struct messages
*/
template <string_literal Literal>
typename std::enable_if<
!SchemaIsArray<typename MessageParameterPackType<
MessageParameterKeyPackIndex<Literal, Keys...>::Value,
V...>::Type>::Value,
typename Container::template ElementType<
MessageParameterKeyPackIndex<Literal,
Keys...>::Value>::builder>::type
init() {
constexpr size_t i =
MessageParameterKeyPackIndex<Literal, Keys...>::Value;
return init<i>();
}
template <size_t i>
typename std::enable_if<
SchemaIsArray<
typename MessageParameterPackType<i, V...>::Type>::Value,
typename Container::template ElementType<i>::builder>::type
init(size_t size = 0) {
auto array_builder =
typename Container::template ElementType<i>::builder{
message_.container_.template get<i>(), size};
return array_builder;
}
/*
* Version for array schema type
*/
template <string_literal Literal>
typename std::enable_if<
SchemaIsArray<typename MessageParameterPackType<
MessageParameterKeyPackIndex<Literal, Keys...>::Value,
V...>::Type>::Value,
typename Container::template ElementType<
MessageParameterKeyPackIndex<Literal,
Keys...>::Value>::builder>::type
init(size_t size) {
constexpr size_t i =
MessageParameterKeyPackIndex<Literal, Keys...>::Value;
return init<i>(size);
}
};
class reader {
private:
MessageType &message_;
public:
reader(MessageType &msg) : message_{msg} {}
builder as_builder() { return builder{message_}; }
/*
* Get member by index
*/
template <size_t i>
typename Container::template ElementType<i>::reader get() {
return typename Container::template ElementType<i>::reader{
message_.container_.template get<i>()};
}
/*
* Get member by name
* This is the preferred method for schema::Struct messages
*/
template <string_literal Literal>
typename Container::template ElementType<
MessageParameterKeyPackIndex<Literal, Keys...>::Value>::reader
get() {
// The index of the first match
constexpr size_t i =
MessageParameterKeyPackIndex<Literal, Keys...>::Value;
return get<i>();
}
};
builder build() { return builder{*this}; }
reader read() { return reader{*this}; }
};
/*
* Union message class. Wrapper object
*/
template <class... V, string_literal... Keys, class Container>
class message<schema::Union<schema::NamedMember<V, Keys>...>, Container> final
: public message_base {
private:
using SchemaType = schema::Union<schema::NamedMember<V, Keys>...>;
using MessageType = message<SchemaType, Container>;
Container container_;
static_assert(std::is_same_v<SchemaType, typename Container::SchemaType>,
"Container should have same the schema as Message");
friend class builder;
friend class reader;
public:
class reader;
class builder {
private:
MessageType &message_;
public:
builder(MessageType &msg) : message_{msg} {}
reader as_reader() { return reader{message_}; }
template <size_t i>
typename std::enable_if<
!SchemaIsArray<
typename MessageParameterPackType<i, V...>::Type>::Value,
typename Container::template ElementType<i>::builder>::type
init() {
return typename Container::template ElementType<i>::builder{
message_.container_.template get<i>()};
}
template <string_literal Literal>
typename std::enable_if<
!SchemaIsArray<typename MessageParameterPackType<
MessageParameterKeyPackIndex<Literal, Keys...>::Value,
V...>::Type>::Value,
typename Container::template ElementType<
MessageParameterKeyPackIndex<Literal,
Keys...>::Value>::builder>::type
init() {
constexpr size_t i =
MessageParameterKeyPackIndex<Literal, Keys...>::Value;
return init<i>();
}
/*
* If Schema is Array
*/
template <size_t i>
typename std::enable_if<
SchemaIsArray<
typename MessageParameterPackType<i, V...>::Type>::Value,
typename Container::template ElementType<i>::builder>::type
init(size_t size = 0) {
return typename Container::template ElementType<i>::builder{
message_.container_.template get<i>(), size};
}
template <string_literal Literal>
typename std::enable_if<
SchemaIsArray<typename MessageParameterPackType<
MessageParameterKeyPackIndex<Literal, Keys...>::Value,
V...>::Type>::Value,
typename Container::template ElementType<
MessageParameterKeyPackIndex<Literal,
Keys...>::Value>::builder>::type
init(size_t size) {
constexpr size_t i =
MessageParameterKeyPackIndex<Literal, Keys...>::Value;
return init<i>(size);
}
};
class reader {
private:
MessageType &message_;
public:
reader(MessageType &msg) : message_{msg} {}
builder as_builder() { return builder{message_}; }
template <size_t i>
typename Container::template ElementType<i>::reader get() {
return typename Container::template ElementType<i>::reader{
message_.container_.template get<i>()};
}
template <string_literal Literal>
typename Container::template ElementType<
MessageParameterKeyPackIndex<Literal, Keys...>::Value>::reader
get() {
// The index of the first match
constexpr size_t i =
MessageParameterKeyPackIndex<Literal, Keys...>::Value;
return get<i>();
}
template <string_literal Literal>
static constexpr size_t toIndex() noexcept {
return MessageParameterKeyPackIndex<Literal, Keys...>::Value;
}
size_t index() const noexcept { return message_.container_.index(); }
template <string_literal Literal> bool hasAlternative() const {
return index() == toIndex<Literal>();
}
};
};
/*
* Array message class. Wrapper around an array schema element
*/
template <class T, class Container>
class message<schema::Array<T>, Container> final : public message_base {
private:
using SchemaType = schema::Array<T>;
using MessageType = message<SchemaType, Container>;
Container container_;
static_assert(std::is_same_v<SchemaType, typename Container::SchemaType>,
"Container should have same Schema as Message");
friend class builder;
friend class reader;
public:
class reader;
class builder {
private:
MessageType &message_;
public:
builder(MessageType &msg, size_t size) : message_{msg} {
if (size > 0) {
message_.container_.resize(size);
}
}
reader as_reader() { return reader{message_}; }
typename Container::ElementType::builder init(size_t i) {
return typename Container::ElementType::builder{
message_.container_.get(i)};
}
size_t size() const { return message_.container_.size(); }
void resize(size_t size) { message_.container_.resize(size); }
};
class reader {
private:
MessageType &message_;
public:
reader(MessageType &msg) : message_{msg} {}
builder as_builder() { return builder{message_, 0}; }
typename Container::ElementType::reader get(size_t i) {
return typename Container::ElementType::reader{
message_.container_.get(i)};
}
size_t size() const { return message_.container_.size(); }
};
};
/*
* Tuple message class. Wrapper around a tuple schema
*/
template <class... T, class Container>
class message<schema::Tuple<T...>, Container> final : public message_base {
private:
using SchemaType = schema::Tuple<T...>;
using MessageType = message<SchemaType, Container>;
Container container_;
static_assert(std::is_same_v<SchemaType, typename Container::SchemaType>,
"Container should have same the schema as Message");
friend class builder;
friend class reader;
public:
class reader;
class builder {
MessageType &message_;
public:
builder(MessageType &msg) : message_{msg} {}
reader as_reader() { return reader{message_}; }
template <size_t i>
typename std::enable_if<
!SchemaIsArray<
typename MessageParameterPackType<i, T...>::Type>::Value,
typename Container::template ElementType<i>::builder>::type
init() {
return typename Container::template ElementType<i>::builder{
message_.container_.template get<i>()};
}
template <size_t i>
typename std::enable_if<
SchemaIsArray<
typename MessageParameterPackType<i, T...>::Type>::Value,
typename Container::template ElementType<i>::builder>::type
init(size_t size = 0) {
return typename Container::template ElementType<i>::builder{
message_.container_.template get<i>(), size};
}
};
class reader {
private:
MessageType &message_;
public:
reader(MessageType &msg) : message_{msg} {}
builder as_builder() { return builder{message_}; }
template <size_t i>
typename Container::template ElementType<i>::reader get() {
return typename Container::template ElementType<i>::reader{
message_.container_.template get<i>()};
}
};
};
/*
* Primitive type (float, double, uint8_t, uint16_t, uint32_t, uint64_t, int8_t,
* int16_t, int32_t, int64_t) message class
*/
template <class T, size_t N, class Container>
class message<schema::Primitive<T, N>, Container> final : public message_base {
private:
using SchemaType = schema::Primitive<T, N>;
using MessageType = message<SchemaType, Container>;
Container container_;
static_assert(std::is_same_v<SchemaType, typename Container::SchemaType>,
"Container should have same the schema as Message");
friend class builder;
friend class reader;
public:
class reader;
class builder {
private:
MessageType &message_;
public:
builder(MessageType &msg) : message_{msg} {}
reader as_reader() { return reader{message_}; }
void set(const typename Container::ValueType &value) {
message_.container_.set(value);
}
};
class reader {
private:
MessageType &message_;
public:
reader(message &msg) : message_{msg} {}
builder as_builder() { return builder{message_}; }
const typename Container::ValueType &get() const {
return message_.container_.get();
}
};
};
template <class Container>
class message<schema::String, Container> final : public message_base {
private:
using SchemaType = schema::String;
using MessageType = message<SchemaType, Container>;
Container container_;
static_assert(std::is_same_v<SchemaType, typename Container::SchemaType>,
"Container should have same the schema as Message");
friend class builder;
friend class reader;
public:
class reader;
class builder {
private:
MessageType &message_;
public:
builder(MessageType &msg) : message_{msg} {}
reader as_reader() { return reader{message_}; }
void set(std::string &&str) { message_.container_.set(std::move(str)); }
void set(const std::string_view str) { message_.container_.set(str); }
void set(const char *str) { set(std::string_view{str}); }
};
class reader {
private:
MessageType &message_;
public:
reader(MessageType &msg) : message_{msg} {}
builder as_builder() { return builder{message_}; }
const std::string_view get() const { return message_.container_.get(); }
};
};
template <class Schema, class Container = message_container<Schema>>
class HeapMessageRoot {
private:
own<message<Schema, Container>> root_;
public:
HeapMessageRoot(own<message<Schema, Container>> r) : root_{std::move(r)} {}
typename message<Schema, Container>::builder build() {
assert(root_);
return typename message<Schema, Container>::builder{*root_};
}
typename message<Schema, Container>::reader read() {
assert(root_);
return typename message<Schema, Container>::reader{*root_};
}
};
template <class T, class Container>
class HeapMessageRoot<schema::Array<T>, Container> {
public:
using Schema = schema::Array<T>;
private:
own<message<Schema, Container>> root_;
public:
HeapMessageRoot(own<message<Schema, Container>> r) : root_{std::move(r)} {}
typename message<Schema, Container>::builder build(size_t size) {
assert(root_);
return typename message<Schema, Container>::builder{*root_, size};
}
typename message<Schema, Container>::reader read() {
assert(root_);
return typename message<Schema, Container>::reader{*root_};
}
};
/*
* Minor helper for creating a message root
*/
template <class Schema, class Container = message_container<Schema>>
inline HeapMessageRoot<Schema, Container> heapMessageRoot() {
own<message<Schema, Container>> root = heap<message<Schema, Container>>();
return HeapMessageRoot<Schema, Container>{std::move(root)};
}
} // namespace saw