#include "config.h"
#include "ScrollBar.h"
#include <algorithm>
using std::max;
using std::min;
namespace WebCore {
Scrollbar::Scrollbar(ScrollbarClient* client, ScrollbarOrientation orientation, ScrollbarControlSize controlSize)
: m_client(client)
, m_orientation(orientation)
, m_controlSize(controlSize)
, m_visibleSize(0)
, m_totalSize(0)
, m_currentPos(0)
, m_lineStep(0)
, m_pageStep(0)
, m_pixelStep(1)
{
}
bool Scrollbar::setValue(int v)
{
v = max(min(v, m_totalSize - m_visibleSize), 0);
if (value() == v)
return false; m_currentPos = v;
updateThumbPosition();
if (client())
client()->valueChanged(this);
return true;
}
void Scrollbar::setProportion(int visibleSize, int totalSize)
{
if (visibleSize == m_visibleSize && totalSize == m_totalSize)
return;
m_visibleSize = visibleSize;
m_totalSize = totalSize;
updateThumbProportion();
}
void Scrollbar::setSteps(int lineStep, int pageStep, int pixelsPerStep)
{
m_lineStep = lineStep;
m_pageStep = pageStep;
m_pixelStep = 1.0f / pixelsPerStep;
}
bool Scrollbar::scroll(ScrollDirection direction, ScrollGranularity granularity, float multiplier)
{
float step = 0;
if ((direction == ScrollUp && m_orientation == VerticalScrollbar) || (direction == ScrollLeft && m_orientation == HorizontalScrollbar))
step = -1;
else if ((direction == ScrollDown && m_orientation == VerticalScrollbar) || (direction == ScrollRight && m_orientation == HorizontalScrollbar))
step = 1;
if (granularity == ScrollByLine)
step *= m_lineStep;
else if (granularity == ScrollByPage)
step *= m_pageStep;
else if (granularity == ScrollByDocument)
step *= m_totalSize;
else if (granularity == ScrollByPixel)
step *= m_pixelStep;
float newPos = m_currentPos + step * multiplier;
float maxPos = m_totalSize - m_visibleSize;
newPos = max(min(newPos, maxPos), 0.0f);
if (newPos == m_currentPos)
return false;
int oldValue = value();
m_currentPos = newPos;
updateThumbPosition();
if (value() != oldValue && client())
client()->valueChanged(this);
return true;
}
}