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#include "qknxnetipconnectionstateresponse.h"

QT_BEGIN_NAMESPACE

/*!
    \class QKnxNetIpConnectionStateResponseProxy

    \inmodule QtKnx
    \ingroup qtknx-netip

    \brief The QKnxNetIpConnectionStateResponseProxy class provides the means to
    read a KNXnet/IP connection state response from the generic
    \l QKnxNetIpFrame class and to create a connection state response frame
    based on the information.

    A KNXnet/IP client reqularly sends a connection state request frame,
    \l QKnxNetIpConnectionStateRequestProxy, to the KNXnet/IP server's control
    endpoint to check the state of a connection established to the server.
    The server responds immediately with a connection state response frame.

    In most programs, this class will not be used directly. Instead, the
    \l QKnxNetIpTunnel or \l QKnxNetIpDeviceManagement
    class is used to establish a functional connection to a KNXnet/IP server.

    \note When using QKnxNetIpConnectionStateResponseProxy, care must be taken
    to ensure that the referenced KNXnet/IP frame outlives the proxy on all code
    paths, lest the proxy ends up referencing deleted data.

    The following code sample illustrates how to read the connection state
    response information sent by a KNXnet/IP server:

    \code
        auto netIpFrame = QKnxNetIpFrame::fromBytes(...);

        const QKnxNetIpConnectionStateResponseProxy proxy(netIpFrame);
        if (!proxy.isValid())
            return;

        auto chanId = proxy.channelId();
        auto status = proxy.status();
    \endcode

    \sa builder(), QKnxNetIpConnectionStateRequestProxy, {Qt KNXnet/IP Connection Classes}
*/

/*!
    \fn QKnxNetIpConnectionStateResponseProxy::QKnxNetIpConnectionStateResponseProxy()
    \internal
*/

/*!
    \fn QKnxNetIpConnectionStateResponseProxy::~QKnxNetIpConnectionStateResponseProxy()
    \internal
*/

/*!
    \fn QKnxNetIpConnectionStateResponseProxy::QKnxNetIpConnectionStateResponseProxy(const QKnxNetIpFrame &&)
    \internal
*/

/*!
    Constructs a proxy object to read the connection state response
    information carried by the specified KNXnet/IP frame \a frame.
*/
QKnxNetIpConnectionStateResponseProxy::QKnxNetIpConnectionStateResponseProxy(const QKnxNetIpFrame &frame)
    : m_frame(frame)
{}

/*!
    Returns the ID of the communication channel prepared by the KNXnet/IP
    server.
*/
quint8 QKnxNetIpConnectionStateResponseProxy::channelId() const
{
    return m_frame.constData().value(0);
}

/*!
    Returns the state of the connection channel established to a KNXnet/IP
    server.
*/
QKnxNetIp::Error QKnxNetIpConnectionStateResponseProxy::status() const
{
    return QKnxNetIp::Error(m_frame.constData().value(1));
}

/*!
    Returns \c true if the frame contains initialized values and is in itself
    valid, otherwise returns \c false. A valid KNXnet/IP frame consists of
    at least a valid header and a size in bytes corresponding to the total size
    of the KNXnet/IP frame header.

    \sa QKnxNetIpFrameHeader::totalSize()
*/
bool QKnxNetIpConnectionStateResponseProxy::isValid() const
{
    return m_frame.isValid() && m_frame.size() == 8
        && m_frame.serviceType() == QKnxNetIp::ServiceType::ConnectionStateResponse;
}

/*!
    Returns a builder object to create a KNXnet/IP connection state response
    frame.
*/
QKnxNetIpConnectionStateResponseProxy::Builder QKnxNetIpConnectionStateResponseProxy::builder()
{
    return QKnxNetIpConnectionStateResponseProxy::Builder();
}


/*!
    \class QKnxNetIpConnectionStateResponseProxy::Builder

    \inmodule QtKnx
    \inheaderfile QKnxNetIpConnectionStateResponseProxy

    \brief The QKnxNetIpConnectionStateResponseProxy::Builder class provides the
    means to create a KNXnet/IP connection state response frame.

    A KNXnet/IP connection state response contains the status of a communication
    channel between a KNXnet/IP client and a KNXnet/IP server.

    In most programs, this class will not be used directly. Instead, the
    \l QKnxNetIpTunnel or \l QKnxNetIpDeviceManagement
    class is used to establish a functional connection to a KNXnet/IP server.

    The common way to create a connection state response is:

    \code
        auto netIpFrame = QKnxNetIpConnectionStateResponseProxy::builder()
            .setChannelId(25)
            .setStatus(QKnx::NetIp::Error::None)
            .create();
    \endcode

    If the KNXnet/IP client does not receive the connection state response
    within a timeout, or the status of the received response indicates that
    errors occurred, the client repeats the connection state request three
    times. It then terminates the connection by sending a disconnect request,
    \l QKnxNetIpDisconnectRequestProxy, to the server's control endpoint.
*/

/*!
    Sets the ID of the communication channel to \a channelId and returns a
    reference to the builder.
*/
QKnxNetIpConnectionStateResponseProxy::Builder &
    QKnxNetIpConnectionStateResponseProxy::Builder::setChannelId(quint8 channelId)
{
    m_channelId = channelId;
    return *this;
}

/*!
    Returns the state of the connection channel established to a KNXnet/IP
    server to \a status and returns a reference to the builder.
*/
QKnxNetIpConnectionStateResponseProxy::Builder &
    QKnxNetIpConnectionStateResponseProxy::Builder::setStatus(QKnxNetIp::Error status)
{
    m_status = status;
    return *this;
}

/*!
    Creates and returns a KNXnet/IP connection state response frame.

    \note The returned frame may be invalid depending on the values used during
    setup.

    \sa isValid()
*/
QKnxNetIpFrame QKnxNetIpConnectionStateResponseProxy::Builder::create() const
{
    QKnxByteArray data;
    switch (m_status) {
    case QKnxNetIp::Error::None:
    case QKnxNetIp::Error::ConnectionId:
    case QKnxNetIp::Error::DataConnection:
    case QKnxNetIp::Error::KnxConnection:
        data = { m_channelId, quint8(m_status) };
        break;
    default:
        break;
    };
    return { QKnxNetIp::ServiceType::ConnectionStateResponse, data };
}

QT_END_NAMESPACE
