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#include "BrowserWindow.h"

#include <QtCore>
#include <QtWidgets>
#include <QPropertyAnimation>
#include <QResizeEvent>

#include "BrowserView.h"
#include "HomeView.h"

BrowserWindow::BrowserWindow()
    : m_slidingSurface(new QWidget(this))
    , m_homeView(new HomeView(m_slidingSurface))
    , m_browserView(new BrowserView(m_slidingSurface))
    , m_animation(new QPropertyAnimation(this, "slideValue"))
{
    m_slidingSurface->setAutoFillBackground(true);

    m_homeView->resize(size());

    m_browserView->resize(size());

    connect(m_homeView, SIGNAL(addressEntered(QString)), SLOT(gotoAddress(QString)));
    connect(m_homeView, SIGNAL(urlActivated(QUrl)), SLOT(navigate(QUrl)));

    connect(m_browserView, SIGNAL(menuButtonClicked()), SLOT(showHomeView()));

    m_animation->setDuration(200);
    connect(m_animation, SIGNAL(finished()), SLOT(animationFinished()));

    setSlideValue(0.0f);
}

void BrowserWindow::gotoAddress(const QString &address)
{
    m_browserView->navigate(QUrl::fromUserInput(address));
    showBrowserView();
}

void BrowserWindow::animationFinished()
{
    m_animation->setDirection(QAbstractAnimation::Forward);
}

void BrowserWindow::navigate(const QUrl &url)
{
    m_browserView->navigate(url);
    showBrowserView();
}

void BrowserWindow::setSlideValue(qreal slideRatio)
{
    // we use a ratio to handle resize corectly
    const int pos = -qRound(slideRatio * width());
    m_slidingSurface->scroll(pos - m_homeView->x(), 0);

    if (qFuzzyCompare(slideRatio, static_cast<qreal>(1.0f))) {
        m_browserView->show();
        m_homeView->hide();
    } else if (qFuzzyCompare(slideRatio, static_cast<qreal>(0.0f))) {
        m_homeView->show();
        m_browserView->hide();
    } else {
        m_browserView->show();
        m_homeView->show();
    }
}

qreal BrowserWindow::slideValue() const
{
    Q_ASSERT(m_slidingSurface->x() < width());
    return static_cast<qreal>(qAbs(m_homeView->x())) / width();
}

void BrowserWindow::showHomeView()
{
    m_animation->setStartValue(slideValue());
    m_animation->setEndValue(0.0f);
    m_animation->start();
    m_homeView->setFocus();
}

void BrowserWindow::showBrowserView()
{
    m_animation->setStartValue(slideValue());
    m_animation->setEndValue(1.0f);
    m_animation->start();

    m_browserView->setFocus();
}

void BrowserWindow::keyReleaseEvent(QKeyEvent *event)
{
    QWidget::keyReleaseEvent(event);

    if (event->key() == Qt::Key_F3) {
        if (m_animation->state() == QAbstractAnimation::Running) {
            const QAbstractAnimation::Direction direction =  m_animation->direction() == QAbstractAnimation::Forward
                                                             ? QAbstractAnimation::Forward
                                                                 : QAbstractAnimation::Backward;
            m_animation->setDirection(direction);
        } else if (qFuzzyCompare(slideValue(), static_cast<qreal>(1.0f)))
            showHomeView();
        else
            showBrowserView();
        event->accept();
    }
}

void BrowserWindow::resizeEvent(QResizeEvent *event)
{
    const QSize oldSize = event->oldSize();
    const qreal oldSlidingRatio = static_cast<qreal>(qAbs(m_homeView->x())) / oldSize.width();

    const QSize newSize = event->size();
    m_slidingSurface->resize(newSize.width() * 2, newSize.height());

    m_homeView->resize(newSize);
    m_homeView->move(0, 0);

    m_browserView->resize(newSize);
    m_browserView->move(newSize.width(), 0);

    setSlideValue(oldSlidingRatio);
}