/* SPDX-License-Identifier: MPL-2.0 */

#include "precompiled.hpp"

#include "v2_protocol.hpp"

#include "v2_encoder.hpp"

#include "msg.hpp"

#include "likely.hpp"

#include "wire.hpp"

#include <limits.h>

zmq::v2_encoder_t::v2_encoder_t (size_t bufsize_) :

    encoder_base_t<v2_encoder_t> (bufsize_)

{

    //  Write 0 bytes to the batch and go to message_ready state.

    next_step (NULL, 0, &v2_encoder_t::message_ready, true);

}

zmq::v2_encoder_t::~v2_encoder_t ()

{

}

void zmq::v2_encoder_t::message_ready ()

{

    //  Encode flags.

    size_t size = in_progress ()->size ();

    size_t header_size = 2; // flags byte + size byte

    unsigned char &protocol_flags = _tmp_buf[0];

    protocol_flags = 0;

    if (in_progress ()->flags () & msg_t::more)

        protocol_flags |= v2_protocol_t::more_flag;

    if (in_progress ()->size () > UCHAR_MAX)

        protocol_flags |= v2_protocol_t::large_flag;

    if (in_progress ()->flags () & msg_t::command)

        protocol_flags |= v2_protocol_t::command_flag;

    if (in_progress ()->is_subscribe () || in_progress ()->is_cancel ())

        ++size;

    //  Encode the message length. For messages less then 256 bytes,

    //  the length is encoded as 8-bit unsigned integer. For larger

    //  messages, 64-bit unsigned integer in network byte order is used.

    if (unlikely (size > UCHAR_MAX)) {

        put_uint64 (_tmp_buf + 1, size);

        header_size = 9; // flags byte + size 8 bytes

    } else {

        _tmp_buf[1] = static_cast<uint8_t> (size);

    }

    //  Encode the subscribe/cancel byte. This is done in the encoder as

    //  opposed to when the subscribe message is created to allow different

    //  protocol behaviour on the wire in the v3.1 and legacy encoders.

    //  It results in the work being done multiple times in case the sub

    //  is sending the subscription/cancel to multiple pubs, but it cannot

    //  be avoided. This processing can be moved to xsub once support for

    //  ZMTP < 3.1 is dropped.

    if (in_progress ()->is_subscribe ())

        _tmp_buf[header_size++] = 1;

    else if (in_progress ()->is_cancel ())

        _tmp_buf[header_size++] = 0;

    next_step (_tmp_buf, header_size, &v2_encoder_t::size_ready, false);

}

void zmq::v2_encoder_t::size_ready ()

{

    //  Write message body into the buffer.

    next_step (in_progress ()->data (), in_progress ()->size (),

               &v2_encoder_t::message_ready, true);

}