ProtocolMessageBase.h

//
// Copyright 2015 - 2024 (C). Alex Robenko. All rights reserved.
//
 
// This file is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 
#pragma once
 
#include <type_traits>
#include <string>
#include <cassert>
 
#include "cc_tools_qt/Message.h"
#include "comms/MessageBase.h"
 
namespace cc_tools_qt
{
 
template <typename TMsgBase, typename TActualMsg>
class ProtocolMessageBase : public TMsgBase
{
    using Base = TMsgBase;
    using ActualMsg = TActualMsg;
 
protected:
 
    ProtocolMessageBase() = default;
 
    ProtocolMessageBase(const ProtocolMessageBase&) = default;
 
    ProtocolMessageBase(ProtocolMessageBase&&) = default;
 
    ~ProtocolMessageBase() noexcept = default;
 
    ProtocolMessageBase& operator=(const ProtocolMessageBase&) = default;
 
    ProtocolMessageBase& operator=(ProtocolMessageBase&&) = default;
 
    virtual void resetImpl() override
    {
        auto& actObj = static_cast<ActualMsg&>(*this);
        actObj = ActualMsg();
    }
 
    virtual bool assignImpl(const cc_tools_qt::Message& other) override
    {
        auto* castedOther = dynamic_cast<const ActualMsg*>(&other);
        if (castedOther == nullptr) {
            return false;
        }
 
        assert(other.idAsString() == Base::idAsString());
        auto& actObj = static_cast<ActualMsg&>(*this);
        actObj = *castedOther;
        return true;
    }
 
    virtual const char* nameImpl() const override
    {
        static_assert(comms::isMessageBase<TMsgBase>(), "TMsgBase is expected to be proper message");
 
        using Tag = typename std::conditional<
                TMsgBase::hasCustomName(),
                HasNameTag,
                NoNameTag
            >::type;
        return nameInternal(Tag());
    }
 
private:
    struct HasNameTag {};
    struct NoNameTag {};
 
    const char* nameInternal(HasNameTag) const
    {
        return TMsgBase::doName();
    }
 
    const char* nameInternal(NoNameTag) const
    {
        [[maybe_unused]] static constexpr bool Must_be_overriden = false;
        assert(Must_be_overriden);         
        return nullptr;
    }
 
};
 
}  // namespace cc_tools_qt