dom_selection.cpp

khtml在gtk上的移植版本

    if (pos.inRenderedContent())
        return true;
        
    // not currently rendered, try moving to prev
    Position prev = pos.previousCharacterPosition();
    if (prev != pos && prev.node()->inSameContainingBlockFlowElement(pos.node())) {
        moveTo(prev);
        return true;
    }

    // could not be moved to prev, try next
    Position next = pos.nextCharacterPosition();
    if (next != pos && next.node()->inSameContainingBlockFlowElement(pos.node())) {
        moveTo(next);
        return true;
    }
    
    return false;
}

bool Selection::nodeIsBeforeNode(NodeImpl *n1, NodeImpl *n2) const
{
    if (!n1 || !n2) 
        return true;

    if (n1 == n2)
        return true;

    bool result = false;
    int n1Depth = 0;
    int n2Depth = 0;

    // First we find the depths of the two nodes in the tree (n1Depth, n2Depth)
    NodeImpl *n = n1;
    while (n->parentNode()) {
        n = n->parentNode();
        n1Depth++;
    }
    n = n2;
    while (n->parentNode()) {
        n = n->parentNode();
        n2Depth++;
    }
    // Climb up the tree with the deeper node, until both nodes have equal depth
    while (n2Depth > n1Depth) {
        n2 = n2->parentNode();
        n2Depth--;
    }
    while (n1Depth > n2Depth) {
        n1 = n1->parentNode();
        n1Depth--;
    }
    // Climb the tree with both n1 and n2 until they have the same parent
    while (n1->parentNode() != n2->parentNode()) {
        n1 = n1->parentNode();
        n2 = n2->parentNode();
    }
    // Iterate through the parent's children until n1 or n2 is found
    n = n1->parentNode() ? n1->parentNode()->firstChild() : n1->firstChild();
    while (n) {
        if (n == n1) {
            result = true;
            break;
        }
        else if (n == n2) {
            result = false;
            break;
        }
        n = n->nextSibling();
    }
    return result;
}

static bool firstRunAt(RenderObject *renderNode, int y, NodeImpl *&startNode, long &startOffset)
{
    for (RenderObject *n = renderNode; n; n = n->nextSibling()) {
        if (n->isText()) {
            RenderText *textRenderer = static_cast<khtml::RenderText *>(n);
            for (InlineTextBox* box = textRenderer->firstTextBox(); box; box = box->nextTextBox()) {
                if (box->m_y == y) {
                    startNode = textRenderer->element();
                    startOffset = box->m_start;
                    return true;
                }
            }
        }
        
        if (firstRunAt(n->firstChild(), y, startNode, startOffset)) {
            return true;
        }
    }
    
    return false;
}

static bool lastRunAt(RenderObject *renderNode, int y, NodeImpl *&endNode, long &endOffset)
{
    RenderObject *n = renderNode;
    if (!n) {
        return false;
    }
    RenderObject *next;
    while ((next = n->nextSibling())) {
        n = next;
    }
    
    while (1) {
        if (lastRunAt(n->firstChild(), y, endNode, endOffset)) {
            return true;
        }
    
        if (n->isText()) {
            RenderText *textRenderer =  static_cast<khtml::RenderText *>(n);
            for (InlineTextBox* box = textRenderer->lastTextBox(); box; box = box->prevTextBox()) {
                if (box->m_y == y) {
                    endNode = textRenderer->element();
                    endOffset = box->m_start + box->m_len;
                    return true;
                }
            }
        }
        
        if (n == renderNode) {
            return false;
        }
        
        n = n->previousSibling();
    }
}

static bool startAndEndLineNodesIncludingNode(NodeImpl *node, int offset, Selection &selection)
{
    if (node && (node->nodeType() == Node::TEXT_NODE || node->nodeType() == Node::CDATA_SECTION_NODE)) {
        int pos;
        int selectionPointY;
        RenderText *renderer = static_cast<RenderText *>(node->renderer());
        InlineTextBox * run = renderer->findNextInlineTextBox( offset, pos );
        DOMString t = node->nodeValue();
        
        if (!run)
            return false;
            
        selectionPointY = run->m_y;
        
        // Go up to first non-inline element.
        khtml::RenderObject *renderNode = renderer;
        while (renderNode && renderNode->isInline())
            renderNode = renderNode->parent();
        
        renderNode = renderNode->firstChild();
        
        NodeImpl *startNode = 0;
        NodeImpl *endNode = 0;
        long startOffset;
        long endOffset;
        
        // Look for all the first child in the block that is on the same line
        // as the selection point.
        if (!firstRunAt (renderNode, selectionPointY, startNode, startOffset))
            return false;
    
        // Look for all the last child in the block that is on the same line
        // as the selection point.
        if (!lastRunAt (renderNode, selectionPointY, endNode, endOffset))
            return false;
        
        selection.moveTo(Position(startNode, startOffset), Position(endNode, endOffset));
        
        return true;
    }
    return false;
}

void Selection::debugRenderer(RenderObject *r, bool selected) const
{
    if (r->node()->isElementNode()) {
        ElementImpl *element = static_cast<ElementImpl *>(r->node());
        fprintf(stderr, "%s%s\n", selected ? "==> " : "    ", element->tagName().string().latin1());
    }
    else if (r->isText()) {
        RenderText *textRenderer = static_cast<RenderText *>(r);
        if (textRenderer->stringLength() == 0 || !textRenderer->firstTextBox()) {
            fprintf(stderr, "%s#text (empty)\n", selected ? "==> " : "    ");
            return;
        }
        
        static const int max = 36;
        QString text = DOMString(textRenderer->string()).string();
        int textLength = text.length();
        if (selected) {
            int offset = 0;
            if (r->node() == start().node())
                offset = start().offset();
            else if (r->node() == end().node())
                offset = end().offset();
                
            int pos;
            InlineTextBox *box = textRenderer->findNextInlineTextBox(offset, pos);
            text = text.mid(box->m_start, box->m_len);
            
            QString show;
            int mid = max / 2;
            int caret = 0;
            
            // text is shorter than max
            if (textLength < max) {
                show = text;
                caret = pos;
            }
            
            // too few characters to left
            else if (pos - mid < 0) {
                show = text.left(max - 3) + "...";
                caret = pos;
            }
            
            // enough characters on each side
            else if (pos - mid >= 0 && pos + mid <= textLength) {
                show = "..." + text.mid(pos - mid + 3, max - 6) + "...";
                caret = mid;
            }
            
            // too few characters on right
            else {
                show = "..." + text.right(max - 3);
                caret = pos - (textLength - show.length());
            }
            
            show = show.replace("\n", " ");
            show = show.replace("\r", " ");
            fprintf(stderr, "==> #text : \"%s\" at offset %d\n", show.latin1(), pos);
            fprintf(stderr, "           ");
            for (int i = 0; i < caret; i++)
                fprintf(stderr, " ");
            fprintf(stderr, "^\n");
        }
        else {
            if ((int)text.length() > max)
                text = text.left(max - 3) + "...";
            else
                text = text.left(max);
            fprintf(stderr, "    #text : \"%s\"\n", text.latin1());
        }
    }
}

void Selection::debugPosition() const
{
    if (!start().node())
        return;

    //static int context = 5;
    
    //RenderObject *r = 0;

    fprintf(stderr, "Selection =================\n");

    if (start() == end()) {
        Position pos = start();
        Position upstream = pos.equivalentUpstreamPosition();
        Position downstream = pos.equivalentDownstreamPosition();
        fprintf(stderr, "upstream:   %s %p:%d\n", getTagName(upstream.node()->id()).string().latin1(), upstream.node(), (int) upstream.offset());
        fprintf(stderr, "pos:        %s %p:%d\n", getTagName(pos.node()->id()).string().latin1(), pos.node(), (int) pos.offset());
        fprintf(stderr, "downstream: %s %p:%d\n", getTagName(downstream.node()->id()).string().latin1(), downstream.node(), (int) downstream.offset());
    }
    else {
        Position pos = start();
        Position upstream = pos.equivalentUpstreamPosition();
        Position downstream = pos.equivalentDownstreamPosition();
        fprintf(stderr, "upstream:   %s %p:%d\n", getTagName(upstream.node()->id()).string().latin1(), upstream.node(), (int) upstream.offset());
        fprintf(stderr, "start:      %s %p:%d\n", getTagName(pos.node()->id()).string().latin1(), pos.node(), (int) pos.offset());
        fprintf(stderr, "downstream: %s %p:%d\n", getTagName(downstream.node()->id()).string().latin1(), downstream.node(), (int) downstream.offset());
        fprintf(stderr, "-----------------------------------\n");
        pos = end();
        upstream = pos.equivalentUpstreamPosition();
        downstream = pos.equivalentDownstreamPosition();
        fprintf(stderr, "upstream:   %s %p:%d\n", getTagName(upstream.node()->id()).string().latin1(), upstream.node(), (int) upstream.offset());
        fprintf(stderr, "end:        %s %p:%d\n", getTagName(pos.node()->id()).string().latin1(), pos.node(), (int) pos.offset());
        fprintf(stderr, "downstream: %s %p:%d\n", getTagName(downstream.node()->id()).string().latin1(), downstream.node(), (int) downstream.offset());
        fprintf(stderr, "-----------------------------------\n");
    }
          
#if 0
    int back = 0;
    r = start().node()->renderer();
    for (int i = 0; i < context; i++, back++) {
        if (r->previousRenderer())
            r = r->previousRenderer();
        else
            break;
    }
    for (int i = 0; i < back; i++) {
        debugRenderer(r, false);
        r = r->nextRenderer();
    }


    fprintf(stderr, "\n");

    if (start().node() == end().node())
        debugRenderer(start().node()->renderer(), true);
    else
        for (r = start().node()->renderer(); r && r != end().node()->renderer(); r = r->nextRenderer())
            debugRenderer(r, true);
    
    fprintf(stderr, "\n");
    
    r = end().node()->renderer();
    for (int i = 0; i < context; i++) {
        if (r->nextRenderer()) {
            r = r->nextRenderer();
            debugRenderer(r, false);
        }
        else
            break;
    }
#endif

    fprintf(stderr, "================================\n");
}

} // namespace DOM