/*
   Copyright (c) 2003,2004,2005 Clarence Dang <dang@kde.org>
   All rights reserved.

   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions
   are met:

   1. Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.
   2. Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in the
      documentation and/or other materials provided with the distribution.

   THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
   IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
   IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
   INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
   THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#define DEBUG_KP_VIEW_SCROLLABLE_CONTAINER 0

#include <kpviewscrollablecontainer.h>

#include <tqcursor.h>
#include <tqpainter.h>
#include <tqpen.h>
#include <tqpixmap.h>
#include <tqtimer.h>

#include <kdebug.h>
#include <tdelocale.h>

#include <kpdefs.h>
#include <kppixmapfx.h>
#include <kpview.h>
#include <kpwidgetmapper.h>


// (Pulled from out of Thurston's hat)
static const int DragScrollLeftTopMargin = 0;
static const int DragScrollRightBottomMargin = 16;  // scrollbarish
static const int DragScrollInterval = 1000 / 10;
static const int DragScrollInitialInterval = DragScrollInterval * 2;
static const int DragScrollNumPixels = 5;
static const int DragDistanceFromRectMaxFor1stMultiplier = 50;
static const int DragDistanceFromRectMaxFor2ndMultiplier = 100;

static const int GripSize = 7;
static const int GripHandleSize = 7;


kpGrip::kpGrip (GripType type,
                TQWidget *parent, const char *name)
    : TQWidget (parent, name),
      m_type (type),
      m_startPoint (KP_INVALID_POINT),
      m_currentPoint (KP_INVALID_POINT),
      m_shouldReleaseMouseButtons (false)
{
    setCursor (cursorForType (m_type));

    setMouseTracking (true);  // mouseMoveEvent's even when no mousebtn down

    updatePixmap ();
}

kpGrip::~kpGrip ()
{
}


// public
kpGrip::GripType kpGrip::type () const
{
    return m_type;
}


// public static
const TQCursor &kpGrip::cursorForType (GripType type)
{
    switch (type)
    {
    case Bottom:
        return TQt::sizeVerCursor;
        break;  // one day you'll forget

    case Right:
        return TQt::sizeHorCursor;
        break;  // one day you'll forget

    case BottomRight:
        return TQt::sizeFDiagCursor;
        break;  // one day you'll forget
    }

    return TQt::arrowCursor;
}


// public
TQRect kpGrip::hotRect (bool toGlobal) const
{
    TQRect ret;

    switch (m_type)
    {
    case Bottom:
    {
        const int handleX = (width () - GripHandleSize) / 2;
        ret = TQRect (handleX, 0,
                     GripHandleSize, height ());
        break;
    }
    case Right:
    {
        const int handleY = (height () - GripHandleSize) / 2;
        ret = TQRect (0, handleY,
                     width (), GripHandleSize);
        break;
    }
    case BottomRight:
        // pixmap all opaque
        ret = rect ();
        break;

    default:
        return TQRect ();
    }

    return (toGlobal ? TQRect (mapToGlobal (ret.topLeft ()),
                              mapToGlobal (ret.bottomRight ()))
                     : ret);
}


// public
bool kpGrip::isDrawing () const
{
    return (m_startPoint != KP_INVALID_POINT);
}


// public
TQString kpGrip::haventBegunDrawUserMessage () const
{
    return i18n ("Left drag the handle to resize the image.");
}


// public
TQString kpGrip::userMessage () const
{
    return m_userMessage;
}

// public
void kpGrip::setUserMessage (const TQString &message)
{
    // Don't do NOP checking here since another grip might have changed
    // the message so an apparent NOP for this grip is not a NOP in the
    // global sense (kpViewScrollableContainer::slotGripStatusMessageChanged()).

    m_userMessage = message;
    emit statusMessageChanged (message);
}


// protected
void kpGrip::updatePixmap ()
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpGrip::updatePixmap() rect=" << rect () << endl;
#endif
    if (width () <= 0 || height () <= 0)
        return;

    TQPixmap pixmap (width (), height ());
    pixmap.fill (colorGroup ().highlight ());
    kpPixmapFX::ensureTransparentAt (&pixmap, pixmap.rect ());
    const TQRect hr = hotRect ();
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "\thotRect=" << hr << endl;
#endif
    if (hr.isValid ())
        kpPixmapFX::ensureOpaqueAt (&pixmap, hr);

    setBackgroundPixmap (pixmap);
    if (pixmap.mask ())
        setMask (*pixmap.mask ());
}


// protected
void kpGrip::cancel ()
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpGrip::cancel()" << endl;
#endif
    if (m_currentPoint == KP_INVALID_POINT)
        return;

    m_startPoint = KP_INVALID_POINT;
    m_currentPoint = KP_INVALID_POINT;

    setUserMessage (i18n ("Resize Image: Let go of all the mouse buttons."));
    setCursor (TQt::arrowCursor);
    m_shouldReleaseMouseButtons = true;

    releaseKeyboard ();
    emit cancelledDraw ();
}


// protected virtual [base TQWidget]
void kpGrip::keyReleaseEvent (TQKeyEvent *e)
{
    if (m_startPoint != KP_INVALID_POINT &&
        e->key () == TQt::Key_Escape)
    {
        cancel ();
    }
}

// protected virtual [base TQWidget]
void kpGrip::mousePressEvent (TQMouseEvent *e)
{
    if (m_startPoint == KP_INVALID_POINT &&
        (e->stateAfter () & Qt::MouseButtonMask) == Qt::LeftButton)
    {
        m_startPoint = e->pos ();
        m_currentPoint = e->pos ();
        emit beganDraw ();
        grabKeyboard ();

        setUserMessage (i18n ("Resize Image: Right click to cancel."));
        setCursor (cursorForType (m_type));
    }
    else
    {
        if (m_startPoint != KP_INVALID_POINT)
            cancel ();
    }
}

// public
TQPoint kpGrip::viewDeltaPoint () const
{
    if (m_startPoint == KP_INVALID_POINT)
        return KP_INVALID_POINT;

    const TQPoint point = mapFromGlobal (TQCursor::pos ());

    // TODO: this is getting out of sync with m_currentPoint

    return TQPoint (((m_type & Right) ? point.x () - m_startPoint.x () : 0),
                   ((m_type & Bottom) ? point.y () - m_startPoint.y () : 0));

}

// public
void kpGrip::mouseMovedTo (const TQPoint &point, bool dueToDragScroll)
{
    if (m_startPoint == KP_INVALID_POINT)
        return;

    m_currentPoint = point;

    emit continuedDraw (((m_type & Right) ? point.x () - m_startPoint.x () : 0),
                        ((m_type & Bottom) ? point.y () - m_startPoint.y () : 0),
                        dueToDragScroll);
}

// protected virtual [base TQWidget]
void kpGrip::mouseMoveEvent (TQMouseEvent *e)
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpGrip::mouseMoveEvent() m_startPoint=" << m_startPoint
               << " stateAfter=" << e->stateAfter ()
               << endl;
#endif

    if (m_startPoint == KP_INVALID_POINT)
    {
        if ((e->stateAfter () & Qt::MouseButtonMask) == 0)
            setUserMessage (haventBegunDrawUserMessage ());
        return;
    }

    mouseMovedTo (e->pos (), false/*not due to drag scroll*/);
}

// protected virtual [base TQWidget]
void kpGrip::mouseReleaseEvent (TQMouseEvent *e)
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpGrip::mouseReleaseEvent() m_startPoint=" << m_startPoint
               << " stateAfter=" << e->stateAfter ()
               << endl;
#endif

    if (m_startPoint != KP_INVALID_POINT)
    {
        const int dx = m_currentPoint.x () - m_startPoint.x (),
                  dy = m_currentPoint.y () - m_startPoint.y ();

        m_currentPoint = KP_INVALID_POINT;
        m_startPoint = KP_INVALID_POINT;

        releaseKeyboard ();
        emit endedDraw ((m_type & Right) ? dx : 0,
                        (m_type & Bottom) ? dy : 0);
    }

    if ((e->stateAfter () & Qt::MouseButtonMask) == 0)
    {
        m_shouldReleaseMouseButtons = false;
        setUserMessage (TQString());
        setCursor (cursorForType (m_type));

        releaseKeyboard ();
        emit releasedAllButtons ();
    }
}


// protected virtual [base TQWidget]
void kpGrip::resizeEvent (TQResizeEvent *)
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpGrip::resizeEvent()" << endl;
#endif
    updatePixmap ();
}


// protected virtual [base TQWidget]
void kpGrip::enterEvent (TQEvent * /*e*/)
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpGrip::enterEvent()"
               << " m_startPoint=" << m_startPoint
               << " shouldReleaseMouseButtons="
               << m_shouldReleaseMouseButtons << endl;
#endif

    if (m_startPoint == KP_INVALID_POINT &&
        !m_shouldReleaseMouseButtons)
    {
    #if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
        kdDebug () << "\tsending message" << endl;
    #endif
        setUserMessage (haventBegunDrawUserMessage ());
    }
}

// protected virtual [base TQWidget]
void kpGrip::leaveEvent (TQEvent * /*e*/)
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpGrip::leaveEvent()"
               << " m_startPoint=" << m_startPoint
               << " shouldReleaseMouseButtons="
               << m_shouldReleaseMouseButtons << endl;
#endif
    if (m_startPoint == KP_INVALID_POINT &&
        !m_shouldReleaseMouseButtons)
    {
        setUserMessage (TQString());
    }
}


// protected virtual [base TQWidget]
void kpGrip::paintEvent (TQPaintEvent *e)
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER && 0
    kdDebug () << "kpGrip::paintEvent(" << e->rect () << ")" << endl;
#endif
    TQWidget::paintEvent (e);
}


// TODO: Are we checking for m_view == 0 often enough?
kpViewScrollableContainer::kpViewScrollableContainer (kpMainWindow *parent,
                                                      const char *name)
    : TQScrollView ((TQWidget *) parent, name, TQt::WStaticContents | TQt::WNoAutoErase),
      m_mainWindow (parent),
      m_contentsXSoon (-1), m_contentsYSoon (-1),
      m_view (0),
      m_bottomGrip (new kpGrip (kpGrip::Bottom, viewport (), "Bottom Grip")),
      m_rightGrip (new kpGrip (kpGrip::Right, viewport (), "Right Grip")),
      m_bottomRightGrip (new kpGrip (kpGrip::BottomRight, viewport (), "BottomRight Grip")),
      m_docResizingGrip (0),
      m_dragScrollTimer (new TQTimer (this)),
      m_zoomLevel (100),
      m_scrollTimerRunOnce (false),
      m_resizeRoundedLastViewX (-1), m_resizeRoundedLastViewY (-1),
      m_resizeRoundedLastViewDX (0), m_resizeRoundedLastViewDY (0),
      m_haveMovedFromOriginalDocSize (false)

{
    m_bottomGrip->setFixedHeight (GripSize);
    m_bottomGrip->hide ();
    addChild (m_bottomGrip);
    connectGripSignals (m_bottomGrip);

    m_rightGrip->setFixedWidth (GripSize);
    m_rightGrip->hide ();
    addChild (m_rightGrip);
    connectGripSignals (m_rightGrip);

    m_bottomRightGrip->setFixedSize (GripSize, GripSize);
    m_bottomRightGrip->hide ();
    addChild (m_bottomRightGrip);
    connectGripSignals (m_bottomRightGrip);


    connect (this, TQT_SIGNAL (contentsMoving (int, int)),
             this, TQT_SLOT (slotContentsMoving (int, int)));

    connect (m_dragScrollTimer, TQT_SIGNAL (timeout ()),
             this, TQT_SLOT (slotDragScroll ()));
}

kpViewScrollableContainer::~kpViewScrollableContainer ()
{
}


// public
int kpViewScrollableContainer::contentsXSoon ()
{
    if (m_contentsXSoon < 0)
        return contentsX ();
    else
        return m_contentsXSoon;
}

// public
int kpViewScrollableContainer::contentsYSoon ()
{
    if (m_contentsYSoon < 0)
        return contentsY ();
    else
        return m_contentsYSoon;
}


// protected
void kpViewScrollableContainer::connectGripSignals (kpGrip *grip)
{
    connect (grip, TQT_SIGNAL (beganDraw ()),
             this, TQT_SLOT (slotGripBeganDraw ()));
    connect (grip, TQT_SIGNAL (continuedDraw (int, int, bool)),
             this, TQT_SLOT (slotGripContinuedDraw (int, int, bool)));
    connect (grip, TQT_SIGNAL (cancelledDraw ()),
             this, TQT_SLOT (slotGripCancelledDraw ()));
    connect (grip, TQT_SIGNAL (endedDraw (int, int)),
             this, TQT_SLOT (slotGripEndedDraw (int, int)));

    connect (grip, TQT_SIGNAL (statusMessageChanged (const TQString &)),
             this, TQT_SLOT (slotGripStatusMessageChanged (const TQString &)));

    connect (grip, TQT_SIGNAL (releasedAllButtons ()),
             this, TQT_SLOT (recalculateStatusMessage ()));
}


// public
TQSize kpViewScrollableContainer::newDocSize () const
{
    return newDocSize (m_resizeRoundedLastViewDX,
                       m_resizeRoundedLastViewDY);
}

// public
bool kpViewScrollableContainer::haveMovedFromOriginalDocSize () const
{
    return m_haveMovedFromOriginalDocSize;
}

// public
TQString kpViewScrollableContainer::statusMessage () const
{
    return m_gripStatusMessage;
}

// public
void kpViewScrollableContainer::clearStatusMessage ()
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER && 1
    kdDebug () << "kpViewScrollableContainer::clearStatusMessage()" << endl;
#endif
    m_bottomRightGrip->setUserMessage (TQString());
    m_bottomGrip->setUserMessage (TQString());
    m_rightGrip->setUserMessage (TQString());
}


// protected
TQSize kpViewScrollableContainer::newDocSize (int viewDX, int viewDY) const
{
    if (!m_view)
        return TQSize ();

    if (!docResizingGrip ())
        return TQSize ();

    const int docX = (int) m_view->transformViewToDocX (m_view->width () + viewDX);
    const int docY = (int) m_view->transformViewToDocY (m_view->height () + viewDY);

    return TQSize (TQMAX (1, docX), TQMAX (1, docY));
}


// protected
void kpViewScrollableContainer::calculateDocResizingGrip ()
{
    if (m_bottomRightGrip->isDrawing ())
        m_docResizingGrip = m_bottomRightGrip;
    else if (m_bottomGrip->isDrawing ())
        m_docResizingGrip = m_bottomGrip;
    else if (m_rightGrip->isDrawing ())
        m_docResizingGrip = m_rightGrip;
    else
        m_docResizingGrip = 0;
}

// protected
kpGrip *kpViewScrollableContainer::docResizingGrip () const
{
    return m_docResizingGrip;
}


// protected
int kpViewScrollableContainer::bottomResizeLineWidth () const
{
    if (!docResizingGrip ())
        return -1;

    if (!m_view)
        return -1;

    if (docResizingGrip ()->type () & kpGrip::Bottom)
        return TQMAX (m_view->zoomLevelY () / 100, 1);
    else
        return 1;
}

// protected
int kpViewScrollableContainer::rightResizeLineWidth () const
{
    if (!docResizingGrip ())
        return -1;

    if (!m_view)
        return -1;

    if (docResizingGrip ()->type () & kpGrip::Right)
        return TQMAX (m_view->zoomLevelX () / 100, 1);
    else
        return 1;
}


// protected
TQRect kpViewScrollableContainer::bottomResizeLineRect () const
{
    if (m_resizeRoundedLastViewX < 0 || m_resizeRoundedLastViewY < 0)
        return TQRect ();

    return TQRect (TQPoint (0,
                          m_resizeRoundedLastViewY),
                  TQPoint (m_resizeRoundedLastViewX - 1,
                          m_resizeRoundedLastViewY + bottomResizeLineWidth () - 1));
}

// protected
TQRect kpViewScrollableContainer::rightResizeLineRect () const
{
    if (m_resizeRoundedLastViewX < 0 || m_resizeRoundedLastViewY < 0)
        return TQRect ();

    return TQRect (TQPoint (m_resizeRoundedLastViewX,
                          0),
                  TQPoint (m_resizeRoundedLastViewX + rightResizeLineWidth () - 1,
                          m_resizeRoundedLastViewY - 1));
}

// protected
TQRect kpViewScrollableContainer::bottomRightResizeLineRect () const
{
    if (m_resizeRoundedLastViewX < 0 || m_resizeRoundedLastViewY < 0)
        return TQRect ();

    return TQRect (TQPoint (m_resizeRoundedLastViewX,
                          m_resizeRoundedLastViewY),
                  TQPoint (m_resizeRoundedLastViewX + rightResizeLineWidth () - 1,
                          m_resizeRoundedLastViewY + bottomResizeLineWidth () - 1));
}


// TODO: are these 2 correct?  Remember that viewport()->x() == 1, viewport()->y() == 1

// protected
TQPoint kpViewScrollableContainer::mapViewToViewport (const TQPoint &viewPoint)
{
    return viewPoint - TQPoint (contentsX (), contentsY ());
}

// protected
TQRect kpViewScrollableContainer::mapViewToViewport (const TQRect &viewRect)
{
    if (!viewRect.isValid ())
        return TQRect ();

    TQRect ret = viewRect;
    ret.moveBy (-contentsX (), -contentsY ());
    return ret;
}


// protected
TQRect kpViewScrollableContainer::mapViewportToGlobal (const TQRect &viewportRect)
{
    return kpWidgetMapper::toGlobal (viewport (), viewportRect);
}

// protected
TQRect kpViewScrollableContainer::mapViewToGlobal (const TQRect &viewRect)
{
    return mapViewportToGlobal (mapViewToViewport (viewRect));
}


// protected
void kpViewScrollableContainer::repaintWidgetAtResizeLineViewRect (
    TQWidget *widget, const TQRect &resizeLineViewRect)
{
    const TQRect resizeLineGlobalRect = mapViewToGlobal (resizeLineViewRect);
    const TQRect widgetGlobalRect = kpWidgetMapper::toGlobal (widget,
                                                             widget->rect ());

    const TQRect redrawGlobalRect =
        resizeLineGlobalRect.intersect (widgetGlobalRect);

    const TQRect redrawWidgetRect =
        kpWidgetMapper::fromGlobal (widget, redrawGlobalRect);


    if (redrawWidgetRect.isValid ())
    {
        // TODO: should be "!widget->testWFlags (TQt::WRepaintNoErase)"
        //       but for some reason, doesn't work for viewport().
        const bool erase = !dynamic_cast <kpView *> (widget);
        widget->repaint (redrawWidgetRect, erase);
    }
}

// protected
void kpViewScrollableContainer::repaintWidgetAtResizeLines (TQWidget *widget)
{
    repaintWidgetAtResizeLineViewRect (widget, rightResizeLineRect ());
    repaintWidgetAtResizeLineViewRect (widget, bottomResizeLineRect ());
    repaintWidgetAtResizeLineViewRect (widget, bottomRightResizeLineRect ());
}

// protected
void kpViewScrollableContainer::eraseResizeLines ()
{
    if (m_resizeRoundedLastViewX >= 0 && m_resizeRoundedLastViewY >= 0)
    {
        repaintWidgetAtResizeLines (viewport ());
        repaintWidgetAtResizeLines (m_view);

        repaintWidgetAtResizeLines (m_bottomGrip);
        repaintWidgetAtResizeLines (m_rightGrip);
        repaintWidgetAtResizeLines (m_bottomRightGrip);
    }
}


// protected
void kpViewScrollableContainer::drawResizeLines ()
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER && 0
    kdDebug () << "kpViewScrollableContainer::drawResizeLines()"
               << " lastViewX=" << m_resizeRoundedLastViewX
               << " lastViewY=" << m_resizeRoundedLastViewY
               << endl;
#endif


    TQPainter p (viewport (), true/*unclipped*/);
    p.setRasterOp (TQt::NotROP);

    const TQRect rightRect = rightResizeLineRect ();
    if (rightRect.isValid ())
        p.fillRect (mapViewToViewport (rightRect), TQt::white);

    const TQRect bottomRect = bottomResizeLineRect ();
    if (bottomRect.isValid ())
        p.fillRect (mapViewToViewport (bottomRect), TQt::white);

    const TQRect bottomRightRect = bottomRightResizeLineRect ();
    if (bottomRightRect.isValid ())
        p.fillRect (mapViewToViewport (bottomRightRect), TQt::white);

    p.end ();
}


// protected
void kpViewScrollableContainer::updateResizeLines (int viewX, int viewY,
                                                   int viewDX, int viewDY)
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER && 0
    kdDebug () << "kpViewScrollableContainer::updateResizeLines("
               << viewX << "," << viewY << ")"
               << " oldViewX=" << m_resizeRoundedLastViewX
               << " oldViewY=" << m_resizeRoundedLastViewY
               << " viewDX=" << viewDX
               << " viewDY=" << viewDY
               << endl;
#endif

    eraseResizeLines ();


    if (viewX >= 0 && viewY >= 0)
    {
        m_resizeRoundedLastViewX = (int) m_view->transformDocToViewX ((int) m_view->transformViewToDocX (viewX));
        m_resizeRoundedLastViewY = (int) m_view->transformDocToViewY ((int) m_view->transformViewToDocY (viewY));

        m_resizeRoundedLastViewDX = viewDX;
        m_resizeRoundedLastViewDY = viewDY;
    }
    else
    {
        m_resizeRoundedLastViewX = -1;
        m_resizeRoundedLastViewY = -1;

        m_resizeRoundedLastViewDX = 0;
        m_resizeRoundedLastViewDY = 0;
    }

    // TODO: This is suboptimal since if another window pops up on top of
    //       KolourPaint then disappears, the lines are not redrawn
    //       (although this doesn't happen very frequently since we grab the
    //       keyboard and mouse when resizing):
    //
    //         e.g. sleep 5 && gedit & sleep 10 && killall gedit
    //
    //       Should be done in the paintEvent's of every child of the
    //       scrollview.
    drawResizeLines ();
}


// protected slot
void kpViewScrollableContainer::slotGripBeganDraw ()
{
    if (!m_view)
        return;

    calculateDocResizingGrip ();

    m_haveMovedFromOriginalDocSize = false;

    updateResizeLines (m_view->width (), m_view->height (),
                       0/*viewDX*/, 0/*viewDY*/);

    emit beganDocResize ();
}

// protected slot
void kpViewScrollableContainer::slotGripContinuedDraw (int inViewDX, int inViewDY,
                                                       bool dueToDragScroll)
{
    int viewDX = inViewDX,
        viewDY = inViewDY;

#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpViewScrollableContainer::slotGripContinuedDraw("
               << viewDX << "," << viewDY << ") size="
               << newDocSize (viewDX, viewDY)
               << " dueToDragScroll=" << dueToDragScroll
               << endl;
#endif

    if (!m_view)
        return;

    if (!dueToDragScroll &&
        beginDragScroll (TQPoint (), TQPoint (), m_view->zoomLevelX ()))
    {
        const TQPoint newViewDeltaPoint = docResizingGrip ()->viewDeltaPoint ();
        viewDX = newViewDeltaPoint.x ();
        viewDY = newViewDeltaPoint.y ();
    #if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
        kdDebug () << "\tdrag scrolled - new view delta point="
                   << newViewDeltaPoint
                   << endl;
    #endif
    }

    m_haveMovedFromOriginalDocSize = true;

    updateResizeLines (TQMAX (1, TQMAX (m_view->width () + viewDX, (int) m_view->transformDocToViewX (1))),
                       TQMAX (1, TQMAX (m_view->height () + viewDY, (int) m_view->transformDocToViewY (1))),
                       viewDX, viewDY);

    emit continuedDocResize (newDocSize ());
}

// protected slot
void kpViewScrollableContainer::slotGripCancelledDraw ()
{
    m_haveMovedFromOriginalDocSize = false;

    updateResizeLines (-1, -1, 0, 0);

    calculateDocResizingGrip ();

    emit cancelledDocResize ();

    endDragScroll ();
}

// protected slot
void kpViewScrollableContainer::slotGripEndedDraw (int viewDX, int viewDY)
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpViewScrollableContainer::slotGripEndedDraw("
               << viewDX << "," << viewDY << ") size="
               << newDocSize (viewDX, viewDY)
               << endl;
#endif

    if (!m_view)
        return;

    const TQSize newSize = newDocSize (viewDX, viewDY);

    m_haveMovedFromOriginalDocSize = false;

    // must erase lines before view size changes
    updateResizeLines (-1, -1, 0, 0);

    calculateDocResizingGrip ();

    emit endedDocResize (newSize);

    endDragScroll ();
}


// protected slot
void kpViewScrollableContainer::slotGripStatusMessageChanged (const TQString &string)
{
    if (string == m_gripStatusMessage)
        return;

    m_gripStatusMessage = string;
    emit statusMessageChanged (string);
}


// public slot
void kpViewScrollableContainer::recalculateStatusMessage ()
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpViewScrollabelContainer::recalculateStatusMessage()" << endl;
    kdDebug () << "\tTQCursor::pos=" << TQCursor::pos ()
               << " global visibleRect="
               << kpWidgetMapper::toGlobal (this,
                      TQRect (0, 0, visibleWidth (), visibleHeight ()))
               << " brGrip.hotRect=" << m_bottomRightGrip->hotRect (true)
               << " bGrip.hotRect=" << m_bottomGrip->hotRect (true)
               << " rGrip.hotRect=" << m_rightGrip->hotRect (true)
               << endl;
#endif

    // HACK: After dragging to a new size, handles move so that they are now
    //       under the mouse pointer but no mouseMoveEvent() is generated for
    //       any grip.  This also handles the case of cancelling over any
    //       grip.
    //
    if (kpWidgetMapper::toGlobal (this,
                                  TQRect (0, 0, visibleWidth (), visibleHeight ()))
            .contains (TQCursor::pos ()))
    {
        if (m_bottomRightGrip->isShown () &&
            m_bottomRightGrip->hotRect (true/*to global*/)
                .contains (TQCursor::pos ()))
        {
            m_bottomRightGrip->setUserMessage (i18n ("Left drag the handle to resize the image."));
        }
        else if (m_bottomGrip->isShown () &&
                m_bottomGrip->hotRect (true/*to global*/)
                    .contains (TQCursor::pos ()))
        {
            m_bottomGrip->setUserMessage (i18n ("Left drag the handle to resize the image."));
        }
        else if (m_rightGrip->isShown () &&
                m_rightGrip->hotRect (true/*to global*/)
                    .contains (TQCursor::pos ()))
        {
            m_rightGrip->setUserMessage (i18n ("Left drag the handle to resize the image."));
        }
        else
        {
            clearStatusMessage ();
        }
    }
    else
    {
        clearStatusMessage ();
    }
}


// protected slot
void kpViewScrollableContainer::slotContentsMoving (int x, int y)
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpViewScrollableContainer::slotContentsMoving("
               << x << "," << y << ")"
               << " contentsX=" << contentsX ()
               << " contentsY=" << contentsY () << endl;
#endif

    m_contentsXSoon = x, m_contentsYSoon = y;
    emit contentsMovingSoon (m_contentsXSoon, m_contentsYSoon);

    // Reduce flicker - don't let TQScrollView scroll to-be-erased lines
    eraseResizeLines ();

    TQTimer::singleShot (0, this, TQT_SLOT (slotContentsMoved ()));
}

// protected slot
void kpViewScrollableContainer::slotContentsMoved ()
{
    m_contentsXSoon = m_contentsYSoon = -1;

    kpGrip *grip = docResizingGrip ();
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpViewScrollableContainer::slotContentsMoved()"
               << " grip=" << grip
               << " contentsX=" << contentsX ()
               << " contentsY=" << contentsY () << endl;
#endif
    if (!grip)
        return;

    grip->mouseMovedTo (grip->mapFromGlobal (TQCursor::pos ()),
                        true/*moved due to drag scroll*/);
}


// protected
void kpViewScrollableContainer::disconnectViewSignals ()
{
    disconnect (m_view, TQT_SIGNAL (sizeChanged (const TQSize &)),
                this, TQT_SLOT (updateGrips ()));
    disconnect (m_view, TQT_SIGNAL (destroyed ()),
                this, TQT_SLOT (slotViewDestroyed ()));
}

// protected
void kpViewScrollableContainer::connectViewSignals ()
{
    connect (m_view, TQT_SIGNAL (sizeChanged (const TQSize &)),
             this, TQT_SLOT (updateGrips ()));
    connect (m_view, TQT_SIGNAL (destroyed ()),
             this, TQT_SLOT (slotViewDestroyed ()));
}


// public virtual [base TQScrollView]
void kpViewScrollableContainer::addChild (TQWidget *widget, int x, int y)
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpViewScrollableContainer::addChild(" << widget
               << "," << x << "," << y << endl;
#endif

    TQScrollView::addChild (widget, x, y);

    kpView *view = dynamic_cast <kpView *> (widget);
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "\tcast to kpView: " << view << endl;
#endif
    if (view)
    {
        setView (view);
    }
}


// public
kpView *kpViewScrollableContainer::view () const
{
    return m_view;
}

// public
void kpViewScrollableContainer::setView (kpView *view)
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpViewScrollableContainer::setView(" << view << ")" << endl;
#endif

    if (m_view == view)
        return;

    if (m_view)
    {
        disconnectViewSignals ();
    }

    m_view = view;

    updateGrips ();

    if (m_view)
    {
        connectViewSignals ();
    }
}


// public slot
void kpViewScrollableContainer::updateGrips ()
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpViewScrollableContainer::updateGrips() m_view="
               << m_view << endl;
#endif

    if (m_view)
    {
        m_bottomGrip->setFixedWidth (m_view->width ());
        moveChild (m_bottomGrip, 0, m_view->height ());

        m_rightGrip->setFixedHeight (m_view->height ());
        moveChild (m_rightGrip, m_view->width (), 0);

        moveChild (m_bottomRightGrip, m_view->width (), m_view->height ());
    }

    m_bottomGrip->setShown (bool (m_view));
    m_rightGrip->setShown (bool (m_view));
    m_bottomRightGrip->setShown (bool (m_view));

#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "\tcontentsRect=" << contentsRect ()
               << " visibleRect=" << visibleRect ()
               << " viewportRect=" << viewport ()->rect ()
               << endl;
#endif

    if (m_view)
    {
        resizeContents (m_view->width () + m_rightGrip->width (),
                        m_view->height () + m_bottomGrip->height ());
    }
    else
    {
        resizeContents (0, 0);
    }

    recalculateStatusMessage ();
}

// protected slot
void kpViewScrollableContainer::slotViewDestroyed ()
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpViewScrollableContainer::slotViewDestroyed() m_view="
               << m_view << endl;
#endif

    m_view = 0;
    updateGrips ();
}


// public slot
bool kpViewScrollableContainer::beginDragScroll (const TQPoint &/*docPoint*/,
                                                 const TQPoint &/*lastDocPoint*/,
                                                 int zoomLevel,
                                                 bool *didSomething)
{
    if (didSomething)
        *didSomething = false;

    m_zoomLevel = zoomLevel;

    const TQPoint p = mapFromGlobal (TQCursor::pos ());

#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpViewScrollableContainer::beginDragScroll() p=" << p
               << " dragScrollTimerRunOnce=" << m_scrollTimerRunOnce
               << endl;
#endif

    bool stopDragScroll = true;
    bool scrolled = false;

    if (!noDragScrollRect ().contains (p))
    {
        if (m_dragScrollTimer->isActive ())
        {
            if (m_scrollTimerRunOnce)
            {
                scrolled = slotDragScroll ();
            }
        }
        else
        {
            m_scrollTimerRunOnce = false;
            m_dragScrollTimer->start (DragScrollInitialInterval);
        }

        stopDragScroll = false;
    }

    if (stopDragScroll)
        m_dragScrollTimer->stop ();

    if (didSomething)
        *didSomething = scrolled;

    return scrolled;
}

// public slot
bool kpViewScrollableContainer::beginDragScroll (const TQPoint &docPoint,
                                                 const TQPoint &lastDocPoint,
                                                 int zoomLevel)
{
    return beginDragScroll (docPoint, lastDocPoint, zoomLevel,
                            0/*don't want scrolled notification*/);
}


// public slot
bool kpViewScrollableContainer::endDragScroll ()
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpViewScrollableContainer::endDragScroll()" << endl;
#endif

    if (m_dragScrollTimer->isActive ())
    {
        m_dragScrollTimer->stop ();
        return true;
    }
    else
    {
        return false;
    }
}


static const int distanceFromRectToMultiplier (int dist)
{
    if (dist < 0)
        return 0;
    else if (dist < DragDistanceFromRectMaxFor1stMultiplier)
        return 1;
    else if (dist < DragDistanceFromRectMaxFor2ndMultiplier)
        return 2;
    else
        return 4;
}


// protected slot
bool kpViewScrollableContainer::slotDragScroll (bool *didSomething)
{
    bool scrolled = false;

    if (didSomething)
        *didSomething = false;


    const TQRect rect = noDragScrollRect ();
    const TQPoint pos = mapFromGlobal (TQCursor::pos ());

#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpViewScrollableContainer::slotDragScroll()"
                  << " noDragScrollRect=" << rect
                  << " pos=" << pos
                  << " contentsX=" << contentsX ()
                  << " contentsY=" << contentsY () << endl;
#endif

    int dx = 0, dy = 0;
    int dxMultiplier = 0, dyMultiplier = 0;

    if (pos.x () < rect.left ())
    {
        dx = -DragScrollNumPixels;
        dxMultiplier = distanceFromRectToMultiplier (rect.left () - pos.x ());
    }
    else if (pos.x () > rect.right ())
    {
        dx = +DragScrollNumPixels;
        dxMultiplier = distanceFromRectToMultiplier (pos.x () - rect.right ());
    }

    if (pos.y () < rect.top ())
    {
        dy = -DragScrollNumPixels;
        dyMultiplier = distanceFromRectToMultiplier (rect.top () - pos.y ());
    }
    else if (pos.y () > rect.bottom ())
    {
        dy = +DragScrollNumPixels;
        dyMultiplier = distanceFromRectToMultiplier (pos.y () - rect.bottom ());
    }

#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER && 0
    kdDebug () << "kpViewScrollableContainer::slotDragScroll()"
                  << " dx=" << dx << " * " << dxMultiplier
                  << " dy=" << dy << " * " << dyMultiplier
                  << " zoomLevel=" << m_zoomLevel
                  << endl;
#endif

    dx *= dxMultiplier;// * TQMAX (1, m_zoomLevel / 100);
    dy *= dyMultiplier;// * TQMAX (1, m_zoomLevel / 100);

    if (dx || dy)
    {
        const int oldContentsX = contentsX (),
                  oldContentsY = contentsY ();

        scrollBy (dx, dy);

    #if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER && 1
        kdDebug () << "\tafter scrollBy():"
                   << " contentsX=" << contentsX ()
                   << " contentsY=" << contentsY () << endl;
    #endif

        scrolled = (oldContentsX != contentsX () ||
                    oldContentsY != contentsY ());

        if (scrolled)
        {
            TQRegion region = TQRect (contentsX (), contentsY (),
                                    visibleWidth (), visibleHeight ());
            region -= TQRect (oldContentsX, oldContentsY,
                             visibleWidth (), visibleHeight ());

            // Repaint newly exposed region immediately to reduce tearing
            // of scrollView.
            m_view->repaint (region, false/*no erase*/);
        }
    }


    m_dragScrollTimer->changeInterval (DragScrollInterval);
    m_scrollTimerRunOnce = true;


    if (didSomething)
        *didSomething = scrolled;

    return scrolled;
}

// protected virtual [base TQScrollView]
void kpViewScrollableContainer::contentsDragMoveEvent (TQDragMoveEvent *e)
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpViewScrollableContainer::contentsDragMoveEvent"
               << e->pos ()
               << endl;
#endif

    TQScrollView::contentsDragMoveEvent (e);
}

// protected slot
bool kpViewScrollableContainer::slotDragScroll ()
{
    return slotDragScroll (0/*don't want scrolled notification*/);
}


// protected virtual [base TQScrollView]
void kpViewScrollableContainer::contentsMouseMoveEvent (TQMouseEvent *e)
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpViewScrollableContainer::contentsMouseMoveEvent"
               << e->pos ()
               << endl;
#endif

    TQScrollView::contentsMouseMoveEvent (e);
}

// protected virtual [base TQScrollView]
void kpViewScrollableContainer::mouseMoveEvent (TQMouseEvent *e)
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpViewScrollableContainer::mouseMoveEvent"
               << e->pos ()
               << endl;
#endif

    TQScrollView::mouseMoveEvent (e);
}


// protected virtual [base TQScrollView]
void kpViewScrollableContainer::contentsWheelEvent (TQWheelEvent *e)
{
    e->ignore ();
    
    if (m_view)
        m_view->wheelEvent (e);
        
    if (!e->isAccepted ())
        TQScrollView::contentsWheelEvent (e);
}


TQRect kpViewScrollableContainer::noDragScrollRect () const
{
    return TQRect (DragScrollLeftTopMargin, DragScrollLeftTopMargin,
                  width () - DragScrollLeftTopMargin - DragScrollRightBottomMargin,
                  height () - DragScrollLeftTopMargin - DragScrollRightBottomMargin);
}

// protected virtual [base TQScrollView]
bool kpViewScrollableContainer::eventFilter (TQObject *watchedObject, TQEvent *event)
{
    return TQScrollView::eventFilter (watchedObject, event);
}

// protected virtual [base TQScrollView]
void kpViewScrollableContainer::viewportPaintEvent (TQPaintEvent *e)
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER
    kdDebug () << "kpViewScrollableContainer::viewportPaintEvent("
               << e->rect ()
               << ")" << endl;
#endif

    TQScrollView::viewportPaintEvent (e);
}

// protected virtual [base TQFrame]
void kpViewScrollableContainer::paintEvent (TQPaintEvent *e)
{
#if DEBUG_KP_VIEW_SCROLLABLE_CONTAINER && 0
    kdDebug () << "kpViewScrollableContainer::paintEvent("
               << e->rect ()
               << ")" << endl;
#endif

    TQScrollView::paintEvent (e);
}

// protected virtual [base TQScrollView]
void kpViewScrollableContainer::resizeEvent (TQResizeEvent *e)
{
    TQScrollView::resizeEvent (e);

    emit resized ();
}


#include <kpviewscrollablecontainer.moc>