String StylePropertySet::get4Values(const StylePropertyShorthand& shorthand) const
{
// Assume the properties are in the usual order top, right, bottom, left.
int topValueIndex = findPropertyIndex(shorthand.properties()[0]);
int rightValueIndex = findPropertyIndex(shorthand.properties()[1]);
int bottomValueIndex = findPropertyIndex(shorthand.properties()[2]);
int leftValueIndex = findPropertyIndex(shorthand.properties()[3]);
if (topValueIndex == -1 || rightValueIndex == -1 || bottomValueIndex == -1 || leftValueIndex == -1)
return String();
PropertyReference top = propertyAt(topValueIndex);
PropertyReference right = propertyAt(rightValueIndex);
PropertyReference bottom = propertyAt(bottomValueIndex);
PropertyReference left = propertyAt(leftValueIndex);
// All 4 properties must be specified.
if (!top.value() || !right.value() || !bottom.value() || !left.value())
return String();
if (top.isInherited() && right.isInherited() && bottom.isInherited() && left.isInherited())
return getValueName(CSSValueInherit);
if (top.value()->isInitialValue() || right.value()->isInitialValue() || bottom.value()->isInitialValue() || left.value()->isInitialValue()) {
if (top.value()->isInitialValue() && right.value()->isInitialValue() && bottom.value()->isInitialValue() && left.value()->isInitialValue() && !top.isImplicit()) {
// All components are "initial" and "top" is not implicit.
return getValueName(CSSValueInitial);
}
return String();
}
if (top.isImportant() != right.isImportant() || right.isImportant() != bottom.isImportant() || bottom.isImportant() != left.isImportant())
return String();
bool showLeft = !right.value()->equals(*left.value());
bool showBottom = !top.value()->equals(*bottom.value()) || showLeft;
bool showRight = !top.value()->equals(*right.value()) || showBottom;
StringBuilder result;
result.append(top.value()->cssText());
if (showRight) {
result.append(' ');
result.append(right.value()->cssText());
}
if (showBottom) {
result.append(' ');
result.append(bottom.value()->cssText());
}
if (showLeft) {
result.append(' ');
result.append(left.value()->cssText());
}
return result.toString();
}
