PRBool HasRTLChars(nsAString& aString)
{
PRInt32 length = aString.Length();
for (PRInt32 i = 0; i < length; i++) {
if ((UCS2_CHAR_IS_BIDI(aString.CharAt(i)) ) ||
((NS_IS_HIGH_SURROGATE(aString.CharAt(i))) &&
(++i < length) &&
(NS_IS_LOW_SURROGATE(aString.CharAt(i))) &&
(UTF32_CHAR_IS_BIDI(SURROGATE_TO_UCS4(aString.CharAt(i-1),
aString.CharAt(i)))))) {
return PR_TRUE;
}
}
return PR_FALSE;
}
void
nsTextBoxFrame::CalculateTitleForWidth(nsPresContext* aPresContext,
nsIRenderingContext& aRenderingContext,
nscoord aWidth)
{
if (mTitle.IsEmpty())
return;
nsLayoutUtils::SetFontFromStyle(&aRenderingContext, GetStyleContext());
// see if the text will completely fit in the width given
mTitleWidth = nsLayoutUtils::GetStringWidth(this, &aRenderingContext,
mTitle.get(), mTitle.Length());
if (mTitleWidth <= aWidth) {
mCroppedTitle = mTitle;
#ifdef IBMBIDI
if (HasRTLChars(mTitle)) {
mState |= NS_FRAME_IS_BIDI;
}
#endif // IBMBIDI
return; // fits, done.
}
const nsDependentString& kEllipsis = nsContentUtils::GetLocalizedEllipsis();
// start with an ellipsis
mCroppedTitle.Assign(kEllipsis);
// see if the width is even smaller than the ellipsis
// if so, clear the text (XXX set as many '.' as we can?).
aRenderingContext.SetTextRunRTL(PR_FALSE);
aRenderingContext.GetWidth(kEllipsis, mTitleWidth);
if (mTitleWidth > aWidth) {
mCroppedTitle.SetLength(0);
mTitleWidth = 0;
return;
}
// if the ellipsis fits perfectly, no use in trying to insert
if (mTitleWidth == aWidth)
return;
aWidth -= mTitleWidth;
// XXX: This whole block should probably take surrogates into account
// XXX and clusters!
// ok crop things
switch (mCropType)
{
case CropNone:
case CropRight:
{
nscoord cwidth;
nscoord twidth = 0;
int length = mTitle.Length();
int i;
for (i = 0; i < length; ++i) {
PRUnichar ch = mTitle.CharAt(i);
// still in LTR mode
aRenderingContext.GetWidth(ch,cwidth);
if (twidth + cwidth > aWidth)
break;
twidth += cwidth;
#ifdef IBMBIDI
if (UCS2_CHAR_IS_BIDI(ch) ) {
mState |= NS_FRAME_IS_BIDI;
}
#endif // IBMBIDI
}
if (i == 0)
return;
// insert what character we can in.
nsAutoString title( mTitle );
title.Truncate(i);
mCroppedTitle.Insert(title, 0);
}
break;
case CropLeft:
{
nscoord cwidth;
nscoord twidth = 0;
int length = mTitle.Length();
int i;
for (i=length-1; i >= 0; --i) {
PRUnichar ch = mTitle.CharAt(i);
aRenderingContext.GetWidth(ch,cwidth);
if (twidth + cwidth > aWidth)
break;
twidth += cwidth;
#ifdef IBMBIDI
if (UCS2_CHAR_IS_BIDI(ch) ) {
mState |= NS_FRAME_IS_BIDI;
}
#endif // IBMBIDI
}
if (i == length-1)
return;
nsAutoString copy;
mTitle.Right(copy, length-1-i);
mCroppedTitle += copy;
}
break;
case CropCenter:
{
nscoord stringWidth =
nsLayoutUtils::GetStringWidth(this, &aRenderingContext,
mTitle.get(), mTitle.Length());
if (stringWidth <= aWidth) {
// the entire string will fit in the maximum width
mCroppedTitle.Insert(mTitle, 0);
break;
}
// determine how much of the string will fit in the max width
nscoord charWidth = 0;
nscoord totalWidth = 0;
PRUnichar ch;
int leftPos, rightPos;
nsAutoString leftString, rightString;
rightPos = mTitle.Length() - 1;
aRenderingContext.SetTextRunRTL(PR_FALSE);
for (leftPos = 0; leftPos <= rightPos;) {
// look at the next character on the left end
ch = mTitle.CharAt(leftPos);
aRenderingContext.GetWidth(ch, charWidth);
totalWidth += charWidth;
if (totalWidth > aWidth)
// greater than the allowable width
break;
leftString.Insert(ch, leftString.Length());
#ifdef IBMBIDI
if (UCS2_CHAR_IS_BIDI(ch))
mState |= NS_FRAME_IS_BIDI;
#endif
// look at the next character on the right end
if (rightPos > leftPos) {
// haven't looked at this character yet
ch = mTitle.CharAt(rightPos);
aRenderingContext.GetWidth(ch, charWidth);
totalWidth += charWidth;
if (totalWidth > aWidth)
// greater than the allowable width
break;
rightString.Insert(ch, 0);
#ifdef IBMBIDI
if (UCS2_CHAR_IS_BIDI(ch))
mState |= NS_FRAME_IS_BIDI;
#endif
}
// look at the next two characters
leftPos++;
rightPos--;
}
mCroppedTitle = leftString + kEllipsis + rightString;
}
break;
}
mTitleWidth = nsLayoutUtils::GetStringWidth(this, &aRenderingContext,
mCroppedTitle.get(), mCroppedTitle.Length());
}