/****************************************************************************
 **
 ** Copyright (C) 2005-2007 Trolltech ASA. All rights reserved.
 **
 ** This file is part of the demonstration applications of the Qt Toolkit.
 **
 ** This file may be used under the terms of the GNU General Public
 ** License version 2.0 as published by the Free Software Foundation
 ** and appearing in the file LICENSE.GPL included in the packaging of
 ** this file.  Please review the following information to ensure GNU
 ** General Public Licensing requirements will be met:
 ** http://trolltech.com/products/qt/licenses/licensing/opensource/
 **
 ** If you are unsure which license is appropriate for your use, please
 ** review the following information:
 ** http://trolltech.com/products/qt/licenses/licensing/licensingoverview
 ** or contact the sales department at sales@trolltech.com.
 **
 ** In addition, as a special exception, Trolltech gives you certain
 ** additional rights. These rights are described in the Trolltech GPL
 ** Exception version 1.0, which can be found at
 ** http://www.trolltech.com/products/qt/gplexception/ and in the file
 ** GPL_EXCEPTION.txt in this package.
 **
 ** In addition, as a special exception, Trolltech, as the sole copyright
 ** holder for Qt Designer, grants users of the Qt/Eclipse Integration
 ** plug-in the right for the Qt/Eclipse Integration to link to
 ** functionality provided by Qt Designer and its related libraries.
 **
 ** Trolltech reserves all rights not expressly granted herein.
 **
 ** Trolltech ASA (c) 2007
 **
 ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 **
 ****************************************************************************/
 
 #include "gradients.h"
 #include "hoverpoints.h"
 
 ShadeWidget::ShadeWidget(ShadeType type, QWidget *parent)
     : QWidget(parent), m_shade_type(type), m_alpha_gradient(QLinearGradient(0, 0, 0, 0))
 {
 
     // Checkers background
     if (m_shade_type == ARGBShade) {
         QPixmap pm(20, 20);
         QPainter pmp(&pm);
         pmp.fillRect(0, 0, 10, 10, Qt::lightGray);
         pmp.fillRect(10, 10, 10, 10, Qt::lightGray);
         pmp.fillRect(0, 10, 10, 10, Qt::darkGray);
         pmp.fillRect(10, 0, 10, 10, Qt::darkGray);
         pmp.end();
         QPalette pal = palette();
         pal.setBrush(backgroundRole(), QBrush(pm));
         setAutoFillBackground(true);
         setPalette(pal);
 
     } else {
         setAttribute(Qt::WA_NoBackground);
 
     }
 
     QPolygonF points;
     points << QPointF(0, sizeHint().height())
            << QPointF(sizeHint().width(), 0);
 
     m_hoverPoints = new HoverPoints(this, HoverPoints::CircleShape);
 //     m_hoverPoints->setConnectionType(HoverPoints::LineConnection);
     m_hoverPoints->setPoints(points);
     m_hoverPoints->setPointLock(0, HoverPoints::LockToLeft);
     m_hoverPoints->setPointLock(1, HoverPoints::LockToRight);
     m_hoverPoints->setSortType(HoverPoints::XSort);
 
     setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);
 
     connect(m_hoverPoints, SIGNAL(pointsChanged(const QPolygonF &)), this, SIGNAL(colorsChanged()));
 }
 
 QPolygonF ShadeWidget::points() const
 {
     return m_hoverPoints->points();
 }
 
 uint ShadeWidget::colorAt(int x)
 {
     generateShade();
 
     QPolygonF pts = m_hoverPoints->points();
     for (int i=1; i < pts.size(); ++i) {
         if (pts.at(i-1).x() <= x && pts.at(i).x() >= x) {
             QLineF l(pts.at(i-1), pts.at(i));
             l.setLength(l.length() * ((x - l.x1()) / l.dx()));
             return m_shade.pixel(qRound(qMin(l.x2(), (qreal(m_shade.width() - 1)))),
                                  qRound(qMin(l.y2(), qreal(m_shade.height() - 1))));
         }
     }
     return 0;
 }
 
 void ShadeWidget::setGradientStops(const QGradientStops &stops)
 {
     if (m_shade_type == ARGBShade) {
         m_alpha_gradient = QLinearGradient(0, 0, width(), 0);
 
         for (int i=0; i<stops.size(); ++i) {
             QColor c = stops.at(i).second;
             m_alpha_gradient.setColorAt(stops.at(i).first, QColor(c.red(), c.green(), c.blue()));
         }
 
         m_shade = QImage();
         generateShade();
         update();
     }
 }
 
 void ShadeWidget::paintEvent(QPaintEvent *)
 {
     generateShade();
 
     QPainter p(this);
     p.drawImage(0, 0, m_shade);
 
     p.setPen(QColor(146, 146, 146));
     p.drawRect(0, 0, width() - 1, height() - 1);
 }
 
 void ShadeWidget::generateShade()
 {
     if (m_shade.isNull() || m_shade.size() != size()) {
 
         if (m_shade_type == ARGBShade) {
             m_shade = QImage(size(), QImage::Format_ARGB32_Premultiplied);
             m_shade.fill(0);
 
             QPainter p(&m_shade);
             p.fillRect(rect(), m_alpha_gradient);
 
             p.setCompositionMode(QPainter::CompositionMode_DestinationIn);
             QLinearGradient fade(0, 0, 0, height());
             fade.setColorAt(0, QColor(0, 0, 0, 255));
             fade.setColorAt(1, QColor(0, 0, 0, 0));
             p.fillRect(rect(), fade);
 
         } else {
             m_shade = QImage(size(), QImage::Format_RGB32);
             QLinearGradient shade(0, 0, 0, height());
             shade.setColorAt(1, Qt::black);
 
             if (m_shade_type == RedShade)
                 shade.setColorAt(0, Qt::red);
             else if (m_shade_type == GreenShade)
                 shade.setColorAt(0, Qt::green);
             else
                 shade.setColorAt(0, Qt::blue);
 
             QPainter p(&m_shade);
             p.fillRect(rect(), shade);
         }
     }
 
 }
 
 GradientEditor::GradientEditor(QWidget *parent)
     : QWidget(parent)
 {
     QVBoxLayout *vbox = new QVBoxLayout(this);
     vbox->setSpacing(1);
     vbox->setMargin(1);
 
     m_red_shade = new ShadeWidget(ShadeWidget::RedShade, this);
     m_green_shade = new ShadeWidget(ShadeWidget::GreenShade, this);
     m_blue_shade = new ShadeWidget(ShadeWidget::BlueShade, this);
     m_alpha_shade = new ShadeWidget(ShadeWidget::ARGBShade, this);
 
     vbox->addWidget(m_red_shade);
     vbox->addWidget(m_green_shade);
     vbox->addWidget(m_blue_shade);
     vbox->addWidget(m_alpha_shade);
 
     connect(m_red_shade, SIGNAL(colorsChanged()), this, SLOT(pointsUpdated()));
     connect(m_green_shade, SIGNAL(colorsChanged()), this, SLOT(pointsUpdated()));
     connect(m_blue_shade, SIGNAL(colorsChanged()), this, SLOT(pointsUpdated()));
     connect(m_alpha_shade, SIGNAL(colorsChanged()), this, SLOT(pointsUpdated()));
 }
 
 inline static bool x_less_than(const QPointF &p1, const QPointF &p2)
 {
     return p1.x() < p2.x();
 }
 
 void GradientEditor::pointsUpdated()
 {
     double w = m_alpha_shade->width();
 
     QGradientStops stops;
 
     QPolygonF points;
 
     points += m_red_shade->points();
     points += m_green_shade->points();
     points += m_blue_shade->points();
     points += m_alpha_shade->points();
 
     qSort(points.begin(), points.end(), x_less_than);
 
     for (int i=0; i<points.size(); ++i) {
         double x = int(points.at(i).x());
         if (i < points.size() - 1 && x == points.at(i+1).x())
             continue;
         QColor color((0x00ff0000 & m_red_shade->colorAt(int(x))) >> 16,
                      (0x0000ff00 & m_green_shade->colorAt(int(x))) >> 8,
                      (0x000000ff & m_blue_shade->colorAt(int(x))),
                      (0xff000000 & m_alpha_shade->colorAt(int(x))) >> 24);
 
         if (x / w > 1)
             return;
 
         stops << QGradientStop(x / w, color);
     }
 
     m_alpha_shade->setGradientStops(stops);
 
     emit gradientStopsChanged(stops);
 }
 
 static void set_shade_points(const QPolygonF &points, ShadeWidget *shade)
 {
     shade->hoverPoints()->setPoints(points);
     shade->hoverPoints()->setPointLock(0, HoverPoints::LockToLeft);
     shade->hoverPoints()->setPointLock(points.size() - 1, HoverPoints::LockToRight);
     shade->update();
 }
 
 void GradientEditor::setGradientStops(const QGradientStops &stops)
 {
     QPolygonF pts_red, pts_green, pts_blue, pts_alpha;
 
     double h_red = m_red_shade->height();
     double h_green = m_green_shade->height();
     double h_blue = m_blue_shade->height();
     double h_alpha = m_alpha_shade->height();
 
     for (int i=0; i<stops.size(); ++i) {
         double pos = stops.at(i).first;
         QRgb color = stops.at(i).second.rgba();
         pts_red << QPointF(pos * m_red_shade->width(), h_red - qRed(color) * h_red / 255);
         pts_green << QPointF(pos * m_green_shade->width(), h_green - qGreen(color) * h_green / 255);
         pts_blue << QPointF(pos * m_blue_shade->width(), h_blue - qBlue(color) * h_blue / 255);
         pts_alpha << QPointF(pos * m_alpha_shade->width(), h_alpha - qAlpha(color) * h_alpha / 255);
     }
 
     set_shade_points(pts_red, m_red_shade);
     set_shade_points(pts_green, m_green_shade);
     set_shade_points(pts_blue, m_blue_shade);
     set_shade_points(pts_alpha, m_alpha_shade);
 
 }
 
 GradientWidget::GradientWidget(QWidget *parent)
     : QWidget(parent)
 {
     setWindowTitle("Gradients");
 
     m_renderer = new GradientRenderer(this);
 
     QGroupBox *mainGroup = new QGroupBox(this);
     mainGroup->setTitle("Gradients");
 
     QGroupBox *editorGroup = new QGroupBox(mainGroup);
     editorGroup->setAttribute(Qt::WA_ContentsPropagated);
     editorGroup->setTitle("Color Editor");
     m_editor = new GradientEditor(editorGroup);
 
     QGroupBox *typeGroup = new QGroupBox(mainGroup);
     typeGroup->setAttribute(Qt::WA_ContentsPropagated);
     typeGroup->setTitle("Gradient Type");
     m_linearButton = new QRadioButton("Linear Gradient", typeGroup);
     m_radialButton = new QRadioButton("Radial Gradient", typeGroup);
     m_conicalButton = new QRadioButton("Conical Gradient", typeGroup);
 
     QGroupBox *spreadGroup = new QGroupBox(mainGroup);
     spreadGroup->setAttribute(Qt::WA_ContentsPropagated);
     spreadGroup->setTitle("Spread Method");
     m_padSpreadButton = new QRadioButton("Pad Spread", spreadGroup);
     m_reflectSpreadButton = new QRadioButton("Reflect Spread", spreadGroup);
     m_repeatSpreadButton = new QRadioButton("Repeat Spread", spreadGroup);
 
     QGroupBox *defaultsGroup = new QGroupBox(mainGroup);
     defaultsGroup->setAttribute(Qt::WA_ContentsPropagated);
     defaultsGroup->setTitle("Defaults");
     QPushButton *default1Button = new QPushButton("1", defaultsGroup);
     QPushButton *default2Button = new QPushButton("2", defaultsGroup);
     QPushButton *default3Button = new QPushButton("3", defaultsGroup);
     QPushButton *default4Button = new QPushButton("Reset", editorGroup);
 
     QPushButton *showSourceButton = new QPushButton(mainGroup);
     showSourceButton->setText("Show Source");
 #ifdef QT_OPENGL_SUPPORT
     QPushButton *enableOpenGLButton = new QPushButton(mainGroup);
     enableOpenGLButton->setText("Use OpenGL");
     enableOpenGLButton->setCheckable(true);
     enableOpenGLButton->setChecked(m_renderer->usesOpenGL());
     if (!QGLFormat::hasOpenGL())
         enableOpenGLButton->hide();
 #endif
     QPushButton *whatsThisButton = new QPushButton(mainGroup);
     whatsThisButton->setText("What's This?");
     whatsThisButton->setCheckable(true);
 
     // Layouts
     QHBoxLayout *mainLayout = new QHBoxLayout(this);
     mainLayout->addWidget(m_renderer);
     mainLayout->addWidget(mainGroup);
 
     mainGroup->setFixedWidth(180);
     QVBoxLayout *mainGroupLayout = new QVBoxLayout(mainGroup);
     mainGroupLayout->addWidget(editorGroup);
     mainGroupLayout->addWidget(typeGroup);
     mainGroupLayout->addWidget(spreadGroup);
     mainGroupLayout->addWidget(defaultsGroup);
     mainGroupLayout->addStretch(1);
     mainGroupLayout->addWidget(showSourceButton);
 #ifdef QT_OPENGL_SUPPORT
     mainGroupLayout->addWidget(enableOpenGLButton);
 #endif
     mainGroupLayout->addWidget(whatsThisButton);
 
     QVBoxLayout *editorGroupLayout = new QVBoxLayout(editorGroup);
     editorGroupLayout->addWidget(m_editor);
 
     QVBoxLayout *typeGroupLayout = new QVBoxLayout(typeGroup);
     typeGroupLayout->addWidget(m_linearButton);
     typeGroupLayout->addWidget(m_radialButton);
     typeGroupLayout->addWidget(m_conicalButton);
 
     QVBoxLayout *spreadGroupLayout = new QVBoxLayout(spreadGroup);
     spreadGroupLayout->addWidget(m_padSpreadButton);
     spreadGroupLayout->addWidget(m_repeatSpreadButton);
     spreadGroupLayout->addWidget(m_reflectSpreadButton);
 
     QHBoxLayout *defaultsGroupLayout = new QHBoxLayout(defaultsGroup);
     defaultsGroupLayout->addWidget(default1Button);
     defaultsGroupLayout->addWidget(default2Button);
     defaultsGroupLayout->addWidget(default3Button);
     editorGroupLayout->addWidget(default4Button);
 
     connect(m_editor, SIGNAL(gradientStopsChanged(const QGradientStops &)),
             m_renderer, SLOT(setGradientStops(const QGradientStops &)));
 
     connect(m_linearButton, SIGNAL(clicked()), m_renderer, SLOT(setLinearGradient()));
     connect(m_radialButton, SIGNAL(clicked()), m_renderer, SLOT(setRadialGradient()));
     connect(m_conicalButton, SIGNAL(clicked()), m_renderer, SLOT(setConicalGradient()));
 
     connect(m_padSpreadButton, SIGNAL(clicked()), m_renderer, SLOT(setPadSpread()));
     connect(m_reflectSpreadButton, SIGNAL(clicked()), m_renderer, SLOT(setReflectSpread()));
     connect(m_repeatSpreadButton, SIGNAL(clicked()), m_renderer, SLOT(setRepeatSpread()));
 
     connect(default1Button, SIGNAL(clicked()), this, SLOT(setDefault1()));
     connect(default2Button, SIGNAL(clicked()), this, SLOT(setDefault2()));
     connect(default3Button, SIGNAL(clicked()), this, SLOT(setDefault3()));
     connect(default4Button, SIGNAL(clicked()), this, SLOT(setDefault4()));
 
     connect(showSourceButton, SIGNAL(clicked()), m_renderer, SLOT(showSource()));
 #ifdef QT_OPENGL_SUPPORT
     connect(enableOpenGLButton, SIGNAL(clicked(bool)), m_renderer, SLOT(enableOpenGL(bool)));
 #endif
     connect(whatsThisButton, SIGNAL(clicked(bool)), m_renderer, SLOT(setDescriptionEnabled(bool)));
     connect(whatsThisButton, SIGNAL(clicked(bool)),
             m_renderer->hoverPoints(), SLOT(setDisabled(bool)));
     connect(m_renderer, SIGNAL(descriptionEnabledChanged(bool)),
             whatsThisButton, SLOT(setChecked(bool)));
     connect(m_renderer, SIGNAL(descriptionEnabledChanged(bool)),
             m_renderer->hoverPoints(), SLOT(setDisabled(bool)));
 
     m_renderer->loadSourceFile(":res/gradients.cpp");
     m_renderer->loadDescription(":res/gradients.html");
 
     QTimer::singleShot(50, this, SLOT(setDefault1()));
 }
 
 void GradientWidget::setDefault(int config)
 {
     QGradientStops stops;
     QPolygonF points;
     switch (config) {
     case 1:
         stops << QGradientStop(0.00, QColor::fromRgba(0));
         stops << QGradientStop(0.04, QColor::fromRgba(0xff131360));
         stops << QGradientStop(0.08, QColor::fromRgba(0xff202ccc));
         stops << QGradientStop(0.42, QColor::fromRgba(0xff93d3f9));
         stops << QGradientStop(0.51, QColor::fromRgba(0xffb3e6ff));
         stops << QGradientStop(0.73, QColor::fromRgba(0xffffffec));
         stops << QGradientStop(0.92, QColor::fromRgba(0xff5353d9));
         stops << QGradientStop(0.96, QColor::fromRgba(0xff262666));
         stops << QGradientStop(1.00, QColor::fromRgba(0));
         m_linearButton->animateClick();
         m_repeatSpreadButton->animateClick();
         break;
 
     case 2:
         stops << QGradientStop(0.00, QColor::fromRgba(0xffffffff));
         stops << QGradientStop(0.11, QColor::fromRgba(0xfff9ffa0));
         stops << QGradientStop(0.13, QColor::fromRgba(0xfff9ff99));
         stops << QGradientStop(0.14, QColor::fromRgba(0xfff3ff86));
         stops << QGradientStop(0.49, QColor::fromRgba(0xff93b353));
         stops << QGradientStop(0.87, QColor::fromRgba(0xff264619));
         stops << QGradientStop(0.96, QColor::fromRgba(0xff0c1306));
         stops << QGradientStop(1.00, QColor::fromRgba(0));
         m_radialButton->animateClick();
         m_padSpreadButton->animateClick();
         break;
 
     case 3:
         stops << QGradientStop(0.00, QColor::fromRgba(0));
         stops << QGradientStop(0.10, QColor::fromRgba(0xffe0cc73));
         stops << QGradientStop(0.17, QColor::fromRgba(0xffc6a006));
         stops << QGradientStop(0.46, QColor::fromRgba(0xff600659));
         stops << QGradientStop(0.72, QColor::fromRgba(0xff0680ac));
         stops << QGradientStop(0.92, QColor::fromRgba(0xffb9d9e6));
         stops << QGradientStop(1.00, QColor::fromRgba(0));
         m_conicalButton->animateClick();
         m_padSpreadButton->animateClick();
         break;
 
     case 4:
         stops << QGradientStop(0.00, QColor::fromRgba(0xff000000));
         stops << QGradientStop(1.00, QColor::fromRgba(0xffffffff));
         break;
 
     default:
         qWarning("bad default: %d\n", config);
         break;
     }
 
     QPolygonF pts;
     int h_off = m_renderer->width() / 10;
     int v_off = m_renderer->height() / 8;
     pts << QPointF(m_renderer->width() / 2, m_renderer->height() / 2)
         << QPointF(m_renderer->width() / 2 - h_off, m_renderer->height() / 2 - v_off);
 
     m_editor->setGradientStops(stops);
     m_renderer->hoverPoints()->setPoints(pts);
     m_renderer->setGradientStops(stops);
 }
 
 GradientRenderer::GradientRenderer(QWidget *parent)
     : ArthurFrame(parent)
 {
     m_hoverPoints = new HoverPoints(this, HoverPoints::CircleShape);
     m_hoverPoints->setPointSize(QSize(20, 20));
     m_hoverPoints->setConnectionType(HoverPoints::NoConnection);
     m_hoverPoints->setEditable(false);
 
     QVector<QPointF> points;
     points << QPointF(100, 100) << QPointF(200, 200);
     m_hoverPoints->setPoints(points);
 
     m_spread = QGradient::PadSpread;
     m_gradientType = Qt::LinearGradientPattern;
 }
 
 void GradientRenderer::setGradientStops(const QGradientStops &stops)
 {
     m_stops = stops;
     update();
 }
 
 void GradientRenderer::mousePressEvent(QMouseEvent *)
 {
     setDescriptionEnabled(false);
 }
 
 void GradientRenderer::paint(QPainter *p)
 {
     QPolygonF pts = m_hoverPoints->points();
 
     QGradient g;
 
     if (m_gradientType == Qt::LinearGradientPattern) {
         g = QLinearGradient(pts.at(0), pts.at(1));
 
     } else if (m_gradientType == Qt::RadialGradientPattern) {
         QLineF line(pts.at(0), pts.at(1));
         if (line.length() > 132)
             line.setLength(132);
         g = QRadialGradient(line.p1(), qMin(width(), height()) / 3.0, line.p2());
     } else {
         QLineF l(pts.at(0), pts.at(1));
         double angle = l.angle(QLineF(0, 0, 1, 0));
         if (l.dy() > 0)
             angle = 360 - angle;
         g = QConicalGradient(pts.at(0), angle);
     }
 
     for (int i=0; i<m_stops.size(); ++i)
         g.setColorAt(m_stops.at(i).first, m_stops.at(i).second);
 
     g.setSpread(m_spread);
 
     p->setBrush(g);
     p->setPen(Qt::NoPen);
 
     p->drawRect(rect());
 
 }