// Token: 0x06005698 RID: 22168 RVA: 0x0017F0C4 File Offset: 0x0017D2C4
internal static Size StackMeasureHelper(IStackMeasure measureElement, IStackMeasureScrollData scrollData, Size constraint)
{
Size size = default(Size);
UIElementCollection internalChildren = measureElement.InternalChildren;
Size availableSize = constraint;
bool flag = measureElement.Orientation == Orientation.Horizontal;
int num = -1;
int i;
double num2;
if (flag)
{
availableSize.Width = double.PositiveInfinity;
if (measureElement.IsScrolling && measureElement.CanVerticallyScroll)
{
availableSize.Height = double.PositiveInfinity;
}
i = (measureElement.IsScrolling ? StackPanel.CoerceOffsetToInteger(scrollData.Offset.X, internalChildren.Count) : 0);
num2 = constraint.Width;
}
else
{
availableSize.Height = double.PositiveInfinity;
if (measureElement.IsScrolling && measureElement.CanHorizontallyScroll)
{
availableSize.Width = double.PositiveInfinity;
}
i = (measureElement.IsScrolling ? StackPanel.CoerceOffsetToInteger(scrollData.Offset.Y, internalChildren.Count) : 0);
num2 = constraint.Height;
}
int j = 0;
int count = internalChildren.Count;
while (j < count)
{
UIElement uielement = internalChildren[j];
if (uielement != null)
{
uielement.Measure(availableSize);
Size desiredSize = uielement.DesiredSize;
double num3;
if (flag)
{
size.Width += desiredSize.Width;
size.Height = Math.Max(size.Height, desiredSize.Height);
num3 = desiredSize.Width;
}
else
{
size.Width = Math.Max(size.Width, desiredSize.Width);
size.Height += desiredSize.Height;
num3 = desiredSize.Height;
}
if (measureElement.IsScrolling && num == -1 && j >= i)
{
num2 -= num3;
if (DoubleUtil.LessThanOrClose(num2, 0.0))
{
num = j;
}
}
}
j++;
}
if (measureElement.IsScrolling)
{
Size viewport = constraint;
Size extent = size;
Vector offset = scrollData.Offset;
if (num == -1)
{
num = internalChildren.Count - 1;
}
while (i > 0)
{
double num4 = num2;
if (flag)
{
num4 -= internalChildren[i - 1].DesiredSize.Width;
}
else
{
num4 -= internalChildren[i - 1].DesiredSize.Height;
}
if (DoubleUtil.LessThan(num4, 0.0))
{
break;
}
i--;
num2 = num4;
}
int count2 = internalChildren.Count;
int num5 = num - i;
if (num5 == 0 || DoubleUtil.GreaterThanOrClose(num2, 0.0))
{
num5++;
}
if (flag)
{
scrollData.SetPhysicalViewport(viewport.Width);
viewport.Width = (double)num5;
extent.Width = (double)count2;
offset.X = (double)i;
offset.Y = Math.Max(0.0, Math.Min(offset.Y, extent.Height - viewport.Height));
}
else
{
scrollData.SetPhysicalViewport(viewport.Height);
viewport.Height = (double)num5;
extent.Height = (double)count2;
offset.Y = (double)i;
offset.X = Math.Max(0.0, Math.Min(offset.X, extent.Width - viewport.Width));
}
size.Width = Math.Min(size.Width, constraint.Width);
size.Height = Math.Min(size.Height, constraint.Height);
StackPanel.VerifyScrollingData(measureElement, scrollData, viewport, extent, offset);
}
return(size);
}