/*****************************************************************************
 * Copyright (C) 2003-2004 Max Howell <max.howell@methylblue.com>            *
 * Copyright (C) 2004-2018 Krusader Krew [https://krusader.org]              *
 *                                                                           *
 * This file is part of Krusader [https://krusader.org].                     *
 *                                                                           *
 * Krusader is free software: you can redistribute it and/or modify          *
 * it under the terms of the GNU General Public License as published by      *
 * the Free Software Foundation, either version 2 of the License, or         *
 * (at your option) any later version.                                       *
 *                                                                           *
 * Krusader is distributed in the hope that it will be useful,               *
 * but WITHOUT ANY WARRANTY; without even the implied warranty of            *
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the             *
 * GNU General Public License for more details.                              *
 *                                                                           *
 * You should have received a copy of the GNU General Public License         *
 * along with Krusader.  If not, see [http://www.gnu.org/licenses/].         *
 *****************************************************************************/

#include "segmentTip.h"

// QtCore
#include <QEvent>
// QtGui
#include <QPainter>
// QtWidgets
#include <QApplication>                           //installing eventFilters
#include <QDesktopWidget>
#include <QToolTip>                               //for its palette

#include <KI18n/KLocalizedString>

#include "fileTree.h"

namespace RadialMap
{

SegmentTip::SegmentTip(uint h)
        : QWidget(0, Qt::FramelessWindowHint | Qt::Tool | Qt::WindowStaysOnTopHint | Qt::X11BypassWindowManagerHint)
        , m_cursorHeight(-h)
{
    setAttribute(Qt::WA_NoSystemBackground, true);
}

void
SegmentTip::moveto(QPoint p, QWidget &canvas, bool placeAbove)
{
    //**** this function is very slow and seems to be visibly influenced by operations like mapFromGlobal() (who knows why!)
    //  ** so any improvements are much desired

    //TODO uints could improve the class
    p.rx() -= rect().center().x();
    p.ry() -= (placeAbove ? 8 + height() : m_cursorHeight - 8);

    const QRect screen = QApplication::desktop()->screenGeometry(parentWidget());

    const int x  = p.x();
    const int y  = p.y();
    const int x2 = x + width();
    const int y2 = y + height(); //how's it ever gunna get below screen height?! (well you never know I spose)
    const int sw = screen.width();
    const int sh = screen.height();

    if (x  < 0) p.setX(0);
    if (y  < 0) p.setY(0);
    if (x2 > sw) p.rx() -= x2 - sw;
    if (y2 > sh) p.ry() -= y2 - sh;


    //I'm using this QPoint to determine where to offset the bitBlt in m_pixmap
    QPoint offset = canvas.mapToGlobal(QPoint()) - p;
    if (offset.x() < 0) offset.setX(0);
    if (offset.y() < 0) offset.setY(0);


    const QRect alphaMaskRect(canvas.mapFromGlobal(p), size());
    const QRect intersection(alphaMaskRect.intersected(canvas.rect()));

    m_pixmap = QPixmap(size());   //move to updateTip once you are sure it can never be null
    //bitBlt( &m_pixmap, offset, &canvas, intersection, Qt::CopyROP );
    QPainter(&m_pixmap).drawPixmap(offset, QPixmap::grabWidget(&canvas, intersection));

    QColor col = QToolTip::palette().color(QPalette::Active, QPalette::Window);
    col.setAlpha(153);   // 0.6

    QRect rct = rect();
    if (rct.width())
        rct.setWidth(rct.width() - 1);
    if (rct.height())
        rct.setHeight(rct.height() - 1);

    QPainter paint(&m_pixmap);
    paint.setPen(Qt::black);
    paint.setBrush(col);
    paint.drawRect(rct);
    paint.end();

    paint.begin(&m_pixmap);
    paint.drawText(rect(), Qt::AlignCenter, m_text);
    paint.end();

    p += screen.topLeft(); //for Xinerama users

    move(x, y);
    show();
    repaint();
}

void
SegmentTip::updateTip(const File* const file, const Directory* const root)
{
    const QString s1  = file->fullPath(root);
    QString s2        = file->humanReadableSize();
    QLocale loc;
    const uint MARGIN = 3;
    const uint pc     = 100 * file->size() / root->size();
    uint maxw         = 0;
    uint h            = fontMetrics().height() * 2 + 2 * MARGIN;

    if (pc > 0) s2 += QString(" (%1%)").arg(loc.toString(pc));

    m_text  = s1;
    m_text += '\n';
    m_text += s2;

    if (file->isDir()) {
        double files  = static_cast<const Directory*>(file)->fileCount();
        const uint pc = uint((100 * files) / (double)root->fileCount());
        QString s3    = i18n("Files: %1", loc.toString(files, 'f', 0));

        if (pc > 0) s3 += QString(" (%1%)").arg(loc.toString(pc));

        maxw    = fontMetrics().width(s3);
        h      += fontMetrics().height();
        m_text += '\n';
        m_text += s3;
    }

    uint
    w = fontMetrics().width(s1); if (w > maxw) maxw = w;
    w = fontMetrics().width(s2); if (w > maxw) maxw = w;

    resize(maxw + 2 * MARGIN, h);
}

bool
SegmentTip::event(QEvent *e)
{
    switch (e->type()) {
    case QEvent::Show:
        qApp->installEventFilter(this);
        break;
    case QEvent::Hide:
        qApp->removeEventFilter(this);
        break;
    case QEvent::Paint: {
        // bitBlt( this, 0, 0, &m_pixmap );
        QPainter(this).drawPixmap(0, 0, m_pixmap);
        return true;
    }
    default:
        ;
    }

    return false/*QWidget::event( e )*/;
}

bool
SegmentTip::eventFilter(QObject*, QEvent *e)
{
    switch (e->type()) {
    case QEvent::Leave:
//    case QEvent::MouseButtonPress:
//    case QEvent::MouseButtonRelease:
    case QEvent::KeyPress:
    case QEvent::KeyRelease:
    case QEvent::FocusIn:
    case QEvent::FocusOut:
    case QEvent::Wheel:
        hide(); //FALL THROUGH
    default:
        return false; //allow this event to passed to target
    }
}

} //namespace RadialMap
