// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only

#include "view.h"

#include <QtGui>

#include "valgrind/callgrind.h"

#ifndef QT_NO_OPENGL
#include <QtOpenGL>
#endif

#include <qmath.h>

class CountView : public QGraphicsView
{
protected:
    void paintEvent(QPaintEvent *event)
    {
        static int n = 0;
        if (n)
            CALLGRIND_START_INSTRUMENTATION
        QGraphicsView::paintEvent(event);
        if (n)
            CALLGRIND_STOP_INSTRUMENTATION
        if (++n == 500)
            qApp->quit();
    }
};

View::View(const QString &name, QWidget *parent)
    : QFrame(parent)
{
    setFrameStyle(Sunken | StyledPanel);
    graphicsView = new CountView;
    graphicsView->setRenderHint(QPainter::Antialiasing, false);
    graphicsView->setDragMode(QGraphicsView::RubberBandDrag);
    graphicsView->setViewportUpdateMode(QGraphicsView::SmartViewportUpdate);

    int size = style()->pixelMetric(QStyle::PM_ToolBarIconSize);
    QSize iconSize(size, size);

    QToolButton *zoomInIcon = new QToolButton;
    zoomInIcon->setAutoRepeat(true);
    zoomInIcon->setAutoRepeatInterval(33);
    zoomInIcon->setAutoRepeatDelay(0);
    zoomInIcon->setIcon(QPixmap(":/zoomin.png"));
    zoomInIcon->setIconSize(iconSize);
    QToolButton *zoomOutIcon = new QToolButton;
    zoomOutIcon->setAutoRepeat(true);
    zoomOutIcon->setAutoRepeatInterval(33);
    zoomOutIcon->setAutoRepeatDelay(0);
    zoomOutIcon->setIcon(QPixmap(":/zoomout.png"));
    zoomOutIcon->setIconSize(iconSize);
    zoomSlider = new QSlider;
    zoomSlider->setMinimum(0);
    zoomSlider->setMaximum(500);
    zoomSlider->setValue(250);
    zoomSlider->setTickPosition(QSlider::TicksRight);

    // Zoom slider layout
    QVBoxLayout *zoomSliderLayout = new QVBoxLayout;
    zoomSliderLayout->addWidget(zoomInIcon);
    zoomSliderLayout->addWidget(zoomSlider);
    zoomSliderLayout->addWidget(zoomOutIcon);

    QToolButton *rotateLeftIcon = new QToolButton;
    rotateLeftIcon->setIcon(QPixmap(":/rotateleft.png"));
    rotateLeftIcon->setIconSize(iconSize);
    QToolButton *rotateRightIcon = new QToolButton;
    rotateRightIcon->setIcon(QPixmap(":/rotateright.png"));
    rotateRightIcon->setIconSize(iconSize);
    rotateSlider = new QSlider;
    rotateSlider->setOrientation(Qt::Horizontal);
    rotateSlider->setMinimum(-360);
    rotateSlider->setMaximum(360);
    rotateSlider->setValue(0);
    rotateSlider->setTickPosition(QSlider::TicksBelow);

    // Rotate slider layout
    QHBoxLayout *rotateSliderLayout = new QHBoxLayout;
    rotateSliderLayout->addWidget(rotateLeftIcon);
    rotateSliderLayout->addWidget(rotateSlider);
    rotateSliderLayout->addWidget(rotateRightIcon);

    resetButton = new QToolButton;
    resetButton->setText(tr("0"));
    resetButton->setEnabled(false);

    // Label layout
    QHBoxLayout *labelLayout = new QHBoxLayout;
    label = new QLabel(name);
    antialiasButton = new QToolButton;
    antialiasButton->setText(tr("Antialiasing"));
    antialiasButton->setCheckable(true);
    antialiasButton->setChecked(false);
    openGlButton = new QToolButton;
    openGlButton->setText(tr("OpenGL"));
    openGlButton->setCheckable(true);
#ifndef QT_NO_OPENGL
    openGlButton->setEnabled(QGLFormat::hasOpenGL());
#else
    openGlButton->setEnabled(false);
#endif
    printButton = new QToolButton;
    printButton->setIcon(QIcon(QPixmap(":/fileprint.png")));

    labelLayout->addWidget(label);
    labelLayout->addStretch();
    labelLayout->addWidget(antialiasButton);
    labelLayout->addWidget(openGlButton);
    labelLayout->addWidget(printButton);

    QGridLayout *topLayout = new QGridLayout;
    topLayout->addLayout(labelLayout, 0, 0);
    topLayout->addWidget(graphicsView, 1, 0);
    topLayout->addLayout(zoomSliderLayout, 1, 1);
    topLayout->addLayout(rotateSliderLayout, 2, 0);
    topLayout->addWidget(resetButton, 2, 1);
    setLayout(topLayout);

    connect(resetButton, SIGNAL(clicked()), this, SLOT(resetView()));
    connect(zoomSlider, SIGNAL(valueChanged(int)), this, SLOT(setupMatrix()));
    connect(rotateSlider, SIGNAL(valueChanged(int)), this, SLOT(setupMatrix()));
    connect(graphicsView->verticalScrollBar(), SIGNAL(valueChanged(int)), this, SLOT(setResetButtonEnabled()));
    connect(graphicsView->horizontalScrollBar(), SIGNAL(valueChanged(int)), this, SLOT(setResetButtonEnabled()));
    connect(antialiasButton, SIGNAL(toggled(bool)), this, SLOT(toggleAntialiasing()));
    connect(openGlButton, SIGNAL(toggled(bool)), this, SLOT(toggleOpenGL()));
    connect(rotateLeftIcon, SIGNAL(clicked()), this, SLOT(rotateLeft()));
    connect(rotateRightIcon, SIGNAL(clicked()), this, SLOT(rotateRight()));
    connect(zoomInIcon, SIGNAL(clicked()), this, SLOT(zoomIn()));
    connect(zoomOutIcon, SIGNAL(clicked()), this, SLOT(zoomOut()));
    connect(printButton, SIGNAL(clicked()), this, SLOT(print()));

    setupMatrix();

    startTimer(0);
}

QGraphicsView *View::view() const
{
    return graphicsView;
}

void View::resetView()
{
    zoomSlider->setValue(250);
    rotateSlider->setValue(0);
    setupMatrix();
    graphicsView->ensureVisible(QRectF(0, 0, 0, 0));

    resetButton->setEnabled(false);
}

void View::setResetButtonEnabled()
{
    resetButton->setEnabled(true);
}

void View::setupMatrix()
{
    qreal scale = qPow(qreal(2), (zoomSlider->value() - 250) / qreal(50));

    QTransform matrix;
    matrix.scale(scale, scale);
    matrix.rotate(rotateSlider->value());

    graphicsView->setMatrix(matrix);
    setResetButtonEnabled();
}

void View::toggleOpenGL()
{
#ifndef QT_NO_OPENGL
    graphicsView->setViewport(openGlButton->isChecked() ? new QGLWidget(QGLFormat(QGL::SampleBuffers)) : new QWidget);
#endif
}

void View::toggleAntialiasing()
{
    graphicsView->setRenderHint(QPainter::Antialiasing, antialiasButton->isChecked());
}

void View::print()
{
#ifndef QT_NO_PRINTER
    QPrinter printer;
    QPrintDialog dialog(&printer, this);
    if (dialog.exec() == QDialog::Accepted) {
        QPainter painter(&printer);
        graphicsView->render(&painter);
    }
#endif
}

void View::zoomIn()
{
    zoomSlider->setValue(zoomSlider->value() + 1);
}

void View::zoomOut()
{
    zoomSlider->setValue(zoomSlider->value() - 1);
}

void View::rotateLeft()
{
    rotateSlider->setValue(rotateSlider->value() - 10);
}

void View::rotateRight()
{
    rotateSlider->setValue(rotateSlider->value() + 10);
}

void View::timerEvent(QTimerEvent *)
{
    graphicsView->horizontalScrollBar()->setValue(graphicsView->horizontalScrollBar()->value() + 1);
}

