/* ****************************************************************************
 * Copyright 2019 Open Systems Development BV                                 *
 *                                                                            *
 * Permission is hereby granted, free of charge, to any person obtaining a    *
 * copy of this software and associated documentation files (the "Software"), *
 * to deal in the Software without restriction, including without limitation  *
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,   *
 * and/or sell copies of the Software, and to permit persons to whom the      *
 * Software is furnished to do so, subject to the following conditions:       *
 *                                                                            *
 * The above copyright notice and this permission notice shall be included in *
 * all copies or substantial portions of the Software.                        *
 *                                                                            *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR *
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,   *
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL    *
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER *
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING    *
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER        *
 * DEALINGS IN THE SOFTWARE.                                                  *
 * ***************************************************************************/
#include "timeline.h"

#include "log.h"

using namespace osdev::components;

Timeline::Timeline()
    : m_timeline(10)
    , m_proposedChange()
{
}

const OrmBatchChange& Timeline::evaluate(const OrmBatchChange& desiredChange, bool exclusiveUpdate)
{
    m_proposedChange = OrmBatchChange {};
    if (m_timeline.full() && desiredChange < m_timeline.front())
    {
        LogWarning("[Timeline::evaluate]", QString("Incoming change (%1) is older then the oldest registered change (%2).").arg(desiredChange.timestamp().toString()).arg(m_timeline.front().timestamp().toString()));
        return m_proposedChange; // change is older then anything we know, discard.
    }

    m_proposedChange = desiredChange;
    for (const auto& ch : m_timeline)
    {
        if (!m_proposedChange.processChange(ch, exclusiveUpdate))
        {
            break;
        }
    }
    if (   m_proposedChange.valid()
        && !m_timeline.empty()
        && m_proposedChange < m_timeline.back())
    {
        // reset the timestamp so that the proposed change will be the latest in the timeline when committed.
        auto ts = m_timeline.back().timestamp();
        m_proposedChange.setTimestamp(++ts);
    }
    return m_proposedChange;
}

void Timeline::commit()
{
    if (m_proposedChange.valid())
    {
        m_timeline.push_back(m_proposedChange);
        m_proposedChange = OrmBatchChange {};
    }
}