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** Copyright (C) 2018 The Qt Company Ltd.
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#include "q3dsscenepicker_p.h"
#include "q3dsscenemanager_p.h"
#include "q3dsinputmanager_p.h"

Q3DSScenePicker::Q3DSScenePicker(Q3DSSceneManager *manager)
    : m_inputManager(manager->inputManager())
{
}

Q3DSScenePicker::~Q3DSScenePicker()
{

}

QPoint Q3DSScenePicker::pickPoint() const
{
    return m_point;
}

Q3DSLayerNode *Q3DSScenePicker::pickLayer() const
{
    return m_layer;
}

bool Q3DSScenePicker::isHit() const
{
    return m_pickResults.size() > 0;
}

void Q3DSScenePicker::pick(const QPoint &point, Q3DSLayerNode *targetLayer)
{
    m_point = point;
    m_layer = targetLayer;
    m_inputManager->pickScene(this);
}

void Q3DSScenePicker::addPick(Q3DSGraphObject *object, qreal distance)
{
    PickResult result;
    result.m_object = object;
    result.m_distance = distance;

    m_pickResults.push_back(result);
}

void Q3DSScenePicker::setState(Q3DSScenePicker::PickState state)
{
    m_pickState = state;
    if (m_pickState == Ready || m_pickState == Failed)
        Q_EMIT ready();
}

void Q3DSScenePicker::setLayerState(Q3DSLayerNode *layer, Q3DSScenePicker::PickState state)
{
    m_layerStates[layer] = state;

    // First state transitions to queued or triggered will change the entire pick state
    if (m_pickState == Unqueued && state == Queued)
        m_pickState = Queued;
    if (m_pickState == Queued && state == Triggered)
        m_pickState = Triggered;

    // If all layer states are set to either Failed or Ready, also change picker state accordingly
    // If all layers failed, then the entire pick failed
    const auto states = m_layerStates.values();
    bool hasReady = false;
    for (const auto state : states) {
        if (state != Failed && state != Ready)
            return;
        else if (state == Ready)
            hasReady = true;
    }

    setState(hasReady ? Ready : Failed);
}

void Q3DSScenePicker::reset()
{
    m_pickState = Unqueued;
    m_layerStates.clear();
    m_pickResults.clear();
}