/****************************************************************************
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** Copyright (C) 2018 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
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** This file is part of Qt 3D Studio.
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** General Public License version 3 as published by the Free Software
** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
** included in the packaging of this file. Please review the following
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#include "NavigationBar.h"
#include "NavigationBarItem.h"
#include "TimelineConstants.h"
#include <QtCore/qdebug.h>

NavigationBar::NavigationBar(QWidget *parent)
    : QWidget(parent)
{
    setMaximumHeight(0);
    m_layout = new QHBoxLayout(this);
    m_layout->setMargin(4);
    m_layout->setSpacing(4);
    setLayout(m_layout);
    // Initialize hide/show animation
    m_expandAnimation.setTargetObject(this);
    m_expandAnimation.setPropertyName("maximumHeight");
    m_expandAnimation.setDuration(TimelineConstants::EXPAND_ANIMATION_DURATION);
}

void NavigationBar::updateNavigationItems(IBreadCrumbProvider *inBreadCrumbProvider)
{
    if (!inBreadCrumbProvider)
        return;

    m_breadCrumbProvider = inBreadCrumbProvider;

    const IBreadCrumbProvider::TTrailList &trailList = m_breadCrumbProvider->GetTrail();
    int listSize = (int)trailList.size();

    // Remove "stretch" from end
    QLayoutItem *stretch = m_layout->takeAt(m_layout->count() - 1);
    if (stretch)
        delete stretch;

    // Update current items or create new as needed
    for (int i = 0; i < listSize; ++i) {
        SBreadCrumb item = trailList.at(i);
        NavigationBarItem *barItem = nullptr;
        bool newItem = (m_itemAmount <= 0) || (i > m_itemAmount - 1);
        if (newItem) {
            barItem = new NavigationBarItem(this);
        } else {
            // Every other item is NavigationBarItem, every other separator
            int barItemIndex = i * 2;
            barItem = static_cast<NavigationBarItem *>(
                        m_layout->itemAt(barItemIndex)->widget());
            barItem->setHighlight(false);
        }
        bool isLastItem = (i == listSize - 1);
        barItem->setEnabled(!isLastItem);
        barItem->setIndex(i);
        barItem->setText(item.m_String);
        if (i == 0)
            barItem->setIcon(m_breadCrumbProvider->GetRootImage());
        else
            barItem->setIcon(m_breadCrumbProvider->GetBreadCrumbImage());

        if (newItem) {
            QObject::connect(barItem, &NavigationBarItem::clicked,
                             this, &NavigationBar::itemClicked);
            if (i != 0) {
                // Separator before all items except first
                QLabel *separator = new QLabel(this);
                separator->setPixmap(m_breadCrumbProvider->GetSeparatorImage());
                m_layout->addWidget(separator);
            }
            m_layout->addWidget(barItem);
        }
    }

    // Remove possible extra items, when user navigates back
    // First item (scene) is never removed
    QLayoutItem *child;
    int lastIndex = (listSize <= 1) ? 1 : (listSize * 2) - 1;
    while ((child = m_layout->takeAt(lastIndex)) != 0) {
        if (child->widget())
            delete child->widget();
        delete child;
    }

    // When list contains single item (scene), hide the bar
    setBarVisibility(listSize > 1);

    // Stretch at end for proper item sizing
    m_layout->addStretch(1);

    m_itemAmount = listSize;
}

void NavigationBar::itemClicked(int index)
{
    m_breadCrumbProvider->OnBreadCrumbClicked((long)index);
}

void NavigationBar::setBarVisibility(bool visible)
{
    int endHeight = visible ? TimelineConstants::NAVIGATION_BAR_H : 0;
    if (height() != endHeight) {
        m_expandAnimation.setEndValue(endHeight);
        m_expandAnimation.start();
    }
}