// Copyright 2020 Proyectos y Sistemas de Mantenimiento SL (eProsima).

//

// Licensed under the Apache License, Version 2.0 (the "License");

// you may not use this file except in compliance with the License.

// You may obtain a copy of the License at

//

//     http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

// limitations under the License.

/**

 * @file RTPSGapBuilder.cpp

 *

 */

#include "RTPSGapBuilder.hpp"

namespace eprosima {

namespace fastrtps {

namespace rtps {

RTPSGapBuilder::~RTPSGapBuilder()

{

    flush();

}

bool RTPSGapBuilder::add(

        const SequenceNumber_t& gap_sequence)

{

    // Check if it is the first gap being added

    if (!is_gap_pending_)

    {

        is_gap_pending_ = true;

        initial_sequence_ = gap_sequence;

        gap_bitmap_.base(gap_sequence + 1);

        return true;

    }

    // Check for contiguous from initial_sequence_

    SequenceNumber_t base = gap_bitmap_.base();

    if (gap_sequence == base)

    {

        gap_bitmap_.base(gap_sequence + 1);

        return true;

    }

    // Check if past last in bitmap

    if (gap_bitmap_.add(gap_sequence))

    {

        return true;

    }

    // Did not fit inside bitmap. Difference between gap_sequence and base is greater than 255.

    // Send GAP with current info and prepare info for next GAP.

    bool ret_val = flush();

    is_gap_pending_ = true;

    initial_sequence_ = gap_sequence;

    gap_bitmap_.base(gap_sequence + 1);

    return ret_val;

}

bool RTPSGapBuilder::flush()

{

    if (is_gap_pending_)

    {

        bool ok = with_specific_destination_ ?

            group_.add_gap(initial_sequence_, gap_bitmap_, reader_guid_) :

            group_.add_gap(initial_sequence_, gap_bitmap_);

        if (!ok)

        {

            return false;

        }

    }

    is_gap_pending_ = false;

    return true;

}

} // namespace rtps

} // namespace fastrtps

} // namespace eprosima