#pragma once
#include <QDataStream>
#include <QLocalSocket>
#include <QByteArray>
#include <functional>

namespace CallCameraProtocol {
enum Type : quint8 { Configure = 1, Quit, Ack, Devices, Frame, Stage, Error, Buffer };
constexpr quint32 FrameBytes = 1920 * 1080 * 4;
constexpr quint32 MaxPacket = 65536;

// Full HD в обеих ориентациях; чётные размеры необходимы для YUV420.
inline bool validSize(int width, int height) {
    return width >= 16 && height >= 16 && width <= 1920 && height <= 1920
        && (width <= 1080 || height <= 1080) && !(width % 2) && !(height % 2);
}

// Только команды и метаданные. Пиксели — в mapping с владением Frame -> Ack, без shared mutex.
inline QByteArray packet(Type type, quint64 generation, const std::function<void(QDataStream&)>& write = {}) {
    QByteArray result;
    QDataStream out(&result, QIODevice::WriteOnly); out.setVersion(QDataStream::Qt_5_15);
    out << quint32(0) << quint8(type) << generation;
    if (write) write(out);
    out.device()->seek(0); out << quint32(result.size() - 4);
    return result;
}

class Reader {
    QByteArray pending;
    quint32 length = 0;
public:
    bool read(QLocalSocket& socket, const std::function<bool(quint8, quint64, QDataStream&)>& consume) {
        while (socket.bytesAvailable()) {
            const qsizetype wanted = length ? length : 4;
            pending += socket.read(wanted - pending.size());
            if (pending.size() != wanted) return true;
            QDataStream in(pending); in.setVersion(QDataStream::Qt_5_15);
            if (!length) {
                in >> length; pending.clear();
                if (length < 9 || length > MaxPacket) return false;
            } else {
                quint8 type; quint64 generation; in >> type >> generation;
                bool valid = consume(type, generation, in) && in.status() == QDataStream::Ok && in.atEnd();
                pending.clear(); length = 0;
                if (!valid) return false;
            }
        }
        return true;
    }
};
}