visible_units.cpp

最新Nokia手机浏览器全套源代码完美版。

    NodeImpl *node = p.node();
    if (!node || !node->getDocument())
        return VisiblePosition();
    
    node->getDocument()->updateLayout();

    RenderObject *renderer = node->renderer();
    if (!renderer)
        return VisiblePosition();

    RenderBlock *containingBlock = 0;
    RootInlineBox *root = 0;
    InlineBox *box = renderer->inlineBox(p.offset(), c.affinity());
    if (box) {
        root = box->root()->nextRootBox();
        if (root)
            containingBlock = renderer->containingBlock();
    }

    if (!root) {
        // This containing editable block does not have a next line.
        // Need to move forward to next containing editable block in this root editable
        // block and find the first root line box in that block.
        NodeImpl *startBlock = node->enclosingBlockFlowElement();
        NodeImpl *n = node->nextEditable();
        while (n && startBlock == n->enclosingBlockFlowElement())
            n = n->nextEditable();
        while (n) {
            if (!n->inSameRootEditableElement(node))
                break;
            Position pos(n, n->caretMinOffset());
            if (pos.inRenderedContent()) {
                assert(n->renderer());
                box = n->renderer()->inlineBox(n->caretMinOffset());
                if (box) {
                    // next root line box found
                    root = box->root();
                    containingBlock = n->renderer()->containingBlock();
                    break;
                }

                return VisiblePosition(pos, DOWNSTREAM);
            }
            n = n->nextEditable();
        }
    }
    
    if (root) {
        int absx, absy;
        containingBlock->absolutePosition(absx, absy);
        RenderObject *renderer = root->closestLeafChildForXPos(x, absx)->object();
        return renderer->positionForCoordinates(x, absy + root->topOverflow());
    }    

    // Could not find a next line. This means we must already be on the last line.
    // Move to the end of the content in this block, which effectively moves us
    // to the end of the line we're on.
    ElementImpl *rootElement = node->rootEditableElement();
    return VisiblePosition(rootElement, rootElement ? rootElement->childNodeCount() : 0, DOWNSTREAM);
}

// ---------

static unsigned startSentenceBoundary(const QChar *characters, unsigned length)
{
    int start, end;
    findSentenceBoundary(characters, length, length, &start, &end);
    return start;
}

VisiblePosition startOfSentence(const VisiblePosition &c)
{
    return previousBoundary(c, startSentenceBoundary);
}

static unsigned endSentenceBoundary(const QChar *characters, unsigned length)
{
    int start, end;
    findSentenceBoundary(characters, length, 0, &start, &end);
    return end;
}

VisiblePosition endOfSentence(const VisiblePosition &c)
{
    return nextBoundary(c, endSentenceBoundary);
}

static unsigned previousSentencePositionBoundary(const QChar *characters, unsigned length)
{
    return nextSentenceFromIndex(characters, length, length, false);
}

VisiblePosition previousSentencePosition(const VisiblePosition &c, int x)
{
    return previousBoundary(c, previousSentencePositionBoundary);
}

static unsigned nextSentencePositionBoundary(const QChar *characters, unsigned length)
{
    return nextSentenceFromIndex(characters, length, 0, true);
}

VisiblePosition nextSentencePosition(const VisiblePosition &c, int x)
{
    return nextBoundary(c, nextSentencePositionBoundary);
}

VisiblePosition startOfParagraph(const VisiblePosition &c)
{
    Position p = c.deepEquivalent();
    NodeImpl *startNode = p.node();
    if (!startNode)
        return VisiblePosition();

    NodeImpl *startBlock = startNode->enclosingBlockFlowElement();

    NodeImpl *node = startNode;
    long offset = p.offset();

    for (NodeImpl *n = startNode; n; n = n->traversePreviousNodePostOrder(startBlock)) {
        RenderObject *r = n->renderer();
        if (!r)
            continue;
        RenderStyle *style = r->style();
        if (style->visibility() != VISIBLE)
            continue;
        if (r->isBR() || r->isBlockFlow())
            break;
        if (r->isText()) {
            if (style->whiteSpace() == PRE) {
                QChar *text = static_cast<RenderText *>(r)->text();
                long i = static_cast<RenderText *>(r)->length();
                long o = offset;
                if (n == startNode && o < i)
                    i = kMax(0L, o);
                while (--i >= 0)
                    if (text[i] == '\n')
                        return VisiblePosition(n, i + 1, DOWNSTREAM);
            }
            node = n;
            offset = 0;
        } else if (r->isReplaced()) {
            node = n;
            offset = 0;
        }
    }

    return VisiblePosition(node, offset, DOWNSTREAM);
}

VisiblePosition endOfParagraph(const VisiblePosition &c, EIncludeLineBreak includeLineBreak)
{
    Position p = c.deepEquivalent();

    NodeImpl *startNode = p.node();
    if (!startNode)
        return VisiblePosition();

    NodeImpl *startBlock = startNode->enclosingBlockFlowElement();
    NodeImpl *stayInsideBlock = includeLineBreak ? 0 : startBlock;
    
    NodeImpl *node = startNode;
    long offset = p.offset();

    for (NodeImpl *n = startNode; n; n = n->traverseNextNode(stayInsideBlock)) {
        if (n->isContentEditable() != startNode->isContentEditable())
            break;
        RenderObject *r = n->renderer();
        if (!r)
            continue;
        RenderStyle *style = r->style();
        if (style->visibility() != VISIBLE)
            continue;
        if (r->isBR()) {
            if (includeLineBreak)
                return VisiblePosition(n, 1, DOWNSTREAM);
            break;
        }
        if (r->isBlockFlow()) {
            if (includeLineBreak)
                return VisiblePosition(n, 0, DOWNSTREAM);
            break;
        }
        // FIXME: We avoid returning a position where the renderer can't accept the caret.
        // We should probably do this in other cases such as startOfParagraph.
        if (r->isText() && r->caretMaxRenderedOffset() > 0) {
            if (includeLineBreak && !n->isAncestor(startBlock))
                return VisiblePosition(n, 0, DOWNSTREAM);
            long length = static_cast<RenderText *>(r)->length();
            if (style->whiteSpace() == PRE) {
                QChar *text = static_cast<RenderText *>(r)->text();
                long o = 0;
                if (n == startNode && offset < length)
                    o = offset;
                for (long i = o; i < length; ++i)
                    if (text[i] == '\n')
                        return VisiblePosition(n, i + includeLineBreak, DOWNSTREAM);
            }
            node = n;
            offset = length;
        } else if (r->isReplaced()) {
            node = n;
            offset = 1;
            if (includeLineBreak && !n->isAncestor(startBlock))
                break;
        }
    }

    return VisiblePosition(node, offset, DOWNSTREAM);
}

bool inSameParagraph(const VisiblePosition &a, const VisiblePosition &b)
{
    return a.isNotNull() && startOfParagraph(a) == startOfParagraph(b);
}

bool isStartOfParagraph(const VisiblePosition &pos)
{
    return pos.isNotNull() && isEqualIgnoringAffinity(pos, startOfParagraph(pos));
}

bool isEndOfParagraph(const VisiblePosition &pos)
{
    return pos.isNotNull() && isEqualIgnoringAffinity(pos, endOfParagraph(pos, DoNotIncludeLineBreak));
}

VisiblePosition previousParagraphPosition(const VisiblePosition &p, int x)
{
    VisiblePosition pos = p;
    do {
        VisiblePosition n = previousLinePosition(pos, x);
        if (n.isNull() || n == pos) {
            return p;
        }
        pos = n;
    } while (inSameParagraph(p, pos));
    return pos;
}

VisiblePosition nextParagraphPosition(const VisiblePosition &p, int x)
{
    VisiblePosition pos = p;
    do {
        VisiblePosition n = nextLinePosition(pos, x);
        if (n.isNull() || n == pos) {
            return p;
        }
        pos = n;
    } while (inSameParagraph(p, pos));
    return pos;
}

// ---------

VisiblePosition startOfBlock(const VisiblePosition &c)
{
    Position p = c.deepEquivalent();
    NodeImpl *startNode = p.node();
    if (!startNode)
        return VisiblePosition();
    return VisiblePosition(Position(startNode->enclosingBlockFlowElement(), 0), DOWNSTREAM);
}

// written, but not yet tested
VisiblePosition endOfBlock(const VisiblePosition &c, EIncludeLineBreak includeLineBreak)
{
    Position p = c.deepEquivalent();

    NodeImpl *startNode = p.node();
    if (!startNode)
        return VisiblePosition();

    NodeImpl *startBlock = startNode->enclosingBlockFlowElement();
    NodeImpl *stayInsideBlock = includeLineBreak ? 0 : startBlock;
    
    NodeImpl *node = startNode;
    long offset = p.offset();

    for (NodeImpl *n = startNode; n; n = n->traverseNextNode(stayInsideBlock)) {
        RenderObject *r = n->renderer();
        if (!r)
            continue;
        RenderStyle *style = r->style();
        if (style->visibility() != VISIBLE)
            continue;
        if (r->isBlockFlow()) {
            if (includeLineBreak)
                return VisiblePosition(n, 0, DOWNSTREAM);
            break;
        }
        if (r->isText()) {
            if (includeLineBreak && !n->isAncestor(startBlock))
                return VisiblePosition(n, 0, DOWNSTREAM);
            node = n;
            offset = static_cast<RenderText *>(r)->length();
        } else if (r->isReplaced()) {
            node = n;
            offset = 1;
            if (includeLineBreak && !n->isAncestor(startBlock))
                break;
        }
    }

    return VisiblePosition(node, offset, DOWNSTREAM);
}

bool inSameBlock(const VisiblePosition &a, const VisiblePosition &b)
{
    return a.isNotNull() && startOfBlock(a) == startOfBlock(b);
}

bool isStartOfBlock(const VisiblePosition &pos)
{
    return pos.isNotNull() && isEqualIgnoringAffinity(pos, startOfBlock(pos));
}

bool isEndOfBlock(const VisiblePosition &pos)
{
    return pos.isNotNull() && isEqualIgnoringAffinity(pos, endOfBlock(pos, DoNotIncludeLineBreak));
}

// ---------

VisiblePosition startOfDocument(const VisiblePosition &c)
{
    Position p = c.deepEquivalent();
    NodeImpl *node = p.node();
    if (!node)
        return VisiblePosition();

    DocumentImpl *doc = node->getDocument();
    if (!doc)
        return VisiblePosition();

    return VisiblePosition(doc->documentElement(), 0, DOWNSTREAM);
}

VisiblePosition endOfDocument(const VisiblePosition &c)
{
    Position p = c.deepEquivalent();
    NodeImpl *node = p.node();
    if (!node)
        return VisiblePosition();

    DocumentImpl *doc = node->getDocument();
    if (!doc)
        return VisiblePosition();

    NodeImpl *docElem = doc->documentElement();
    if (!node)
        return VisiblePosition();

    return VisiblePosition(docElem, docElem->childNodeCount(), DOWNSTREAM);
}

bool inSameDocument(const VisiblePosition &a, const VisiblePosition &b)
{
    Position ap = a.deepEquivalent();
    NodeImpl *an = ap.node();
    if (!an)
        return false;
    Position bp = b.deepEquivalent();
    NodeImpl *bn = bp.node();
    if (an == bn)
        return true;

    return an->getDocument() == bn->getDocument();
}

bool isStartOfDocument(const VisiblePosition &p)
{
    return p.isNotNull() && p.previous().isNull();
}

bool isEndOfDocument(const VisiblePosition &p)
{
    return p.isNotNull() && p.next().isNull();
}

// ---------

VisiblePosition startOfEditableContent(const VisiblePosition &c)
{
    Position p = c.deepEquivalent();
    NodeImpl *node = p.node();
    if (!node)
        return VisiblePosition();

    return VisiblePosition(node->rootEditableElement(), 0, DOWNSTREAM);
}

VisiblePosition endOfEditableContent(const VisiblePosition &c)
{
    Position p = c.deepEquivalent();
    NodeImpl *node = p.node();
    if (!node)
        return VisiblePosition();

    node = node->rootEditableElement();
    if (!node)
        return VisiblePosition();

    return VisiblePosition(node, node->childNodeCount(), DOWNSTREAM);
}

bool inSameEditableContent(const VisiblePosition &a, const VisiblePosition &b)
{
    Position ap = a.deepEquivalent();
    NodeImpl *an = ap.node();
    if (!an)
        return false;
        
    Position bp = b.deepEquivalent();
    NodeImpl *bn = bp.node();
    if (!bn)
        return false;
    
    if (!an->isContentEditable() || !bn->isContentEditable())
        return false;

    return an->rootEditableElement() == bn->rootEditableElement();
}

bool isStartOfEditableContent(const VisiblePosition &p)
{
    return inSameEditableContent(p, p.previous());
}

bool isEndOfEditableContent(const VisiblePosition &p)
{
    return inSameEditableContent(p, p.next());
}

} // namespace khtml