WebCore/editing/InsertTextCommand.cpp

/*
 * Copyright (C) 2005 Apple Computer, Inc.  All rights reserved.
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#include "config.h"
#include "InsertTextCommand.h"

#include "CSSMutableStyleDeclaration.h"
#include "Document.h"
#include "Element.h"
#include "EditingText.h"
#include "Frame.h"
#include "Logging.h"
#include "HTMLInterchange.h"
#include "htmlediting.h"
#include "TextIterator.h"
#include "visible_units.h"

namespace WebCore {

InsertTextCommand::InsertTextCommand(Document *document) 
    : CompositeEditCommand(document), m_charactersAdded(0)
{
}

void InsertTextCommand::doApply()
{
}

Position InsertTextCommand::prepareForTextInsertion(const Position& pos)
{
    // Prepare for text input by looking at the specified position.
    // It may be necessary to insert a text node to receive characters.
    // FIXME: What is the rootEditable() check about?  Seems like it
    // assumes that the content before (or after) pos.node() is editable
    // (i.e. pos is at an editable/non-editable boundary).  That seems
    // like a bad assumption.
    if (!pos.node()->isTextNode()) {
        RefPtr<Node> textNode = document()->createEditingTextNode("");

        // Now insert the node in the right place
        if (pos.node()->rootEditableElement() != NULL) {
            insertNodeAt(textNode.get(), pos.node(), pos.offset());
        } else if (pos.node()->caretMinOffset() == pos.offset()) {
            insertNodeBefore(textNode.get(), pos.node());
        } else if (pos.node()->caretMaxOffset() == pos.offset()) {
            insertNodeAfter(textNode.get(), pos.node());
        } else
            ASSERT_NOT_REACHED();
        
        return Position(textNode.get(), 0);
    }

    if (isTabSpanTextNode(pos.node())) {
        RefPtr<Node> textNode = document()->createEditingTextNode("");
        insertNodeAtTabSpanPosition(textNode.get(), pos);
        return Position(textNode.get(), 0);
    }

    return pos;
}

void InsertTextCommand::input(const String &text, bool selectInsertedText)
{
    assert(text.find('\n') == -1);

    Selection selection = endingSelection();
    // FIXME: I don't see how "start of line" could possibly be the right check here.
    // It depends on line breaks which depends on the way things are current laid out,
    // window width, etc. This needs to be rethought.
    bool adjustDownstream = isStartOfLine(VisiblePosition(selection.start().downstream(), DOWNSTREAM));

    // Delete the current selection, or collapse whitespace, as needed
    if (selection.isRange())
        deleteSelection();
    
    // Delete any insignificant text that could get in the way of whitespace turning
    // out correctly after the insertion.
    selection = endingSelection();
    deleteInsignificantTextDownstream(selection.end().trailingWhitespacePosition(selection.affinity()));

    // Figure out the startPosition
    Position startPosition = selection.start();
    Position endPosition;
    if (adjustDownstream)
        startPosition = startPosition.downstream();
    else
        startPosition = startPosition.upstream();
    startPosition = positionAvoidingSpecialElementBoundary(startPosition);
    
    if (text == "\t") {
        endPosition = insertTab(startPosition);
        startPosition = endPosition.previous();
        removeBlockPlaceholder(startPosition.node()->enclosingBlockFlowElement());
        m_charactersAdded += 1;
    } else {
        // Make sure the document is set up to receive text
        startPosition = prepareForTextInsertion(startPosition);
        removeBlockPlaceholder(startPosition.node()->enclosingBlockFlowElement());
        Text *textNode = static_cast<Text *>(startPosition.node());
        int offset = startPosition.offset();

        insertTextIntoNode(textNode, offset, text);
        endPosition = Position(textNode, offset + text.length());

        // The insertion may require adjusting adjacent whitespace, if it is present.
        rebalanceWhitespaceAt(endPosition);
        // Rebalancing on both sides isn't necessary if we've inserted a space.
        if (text != " ") 
            rebalanceWhitespaceAt(startPosition);
            
        m_charactersAdded += text.length();
    }

    setEndingSelection(Selection(startPosition, endPosition, DOWNSTREAM));

    // Handle the case where there is a typing style.
    // FIXME: Improve typing style.
    // See this bug: <rdar://problem/3769899> Implementation of typing style needs improvement
    CSSMutableStyleDeclaration* typingStyle = document()->frame()->typingStyle();
    if (typingStyle && typingStyle->length() > 0)
        applyStyle(typingStyle);

    if (!selectInsertedText)
        setEndingSelection(endingSelection().end(), endingSelection().affinity());
}

WebCore::Position InsertTextCommand::insertTab(Position pos)
{
    Position insertPos = VisiblePosition(pos, DOWNSTREAM).deepEquivalent();
    Node *node = insertPos.node();
    unsigned int offset = insertPos.offset();

    // keep tabs coalesced in tab span
    if (isTabSpanTextNode(node)) {
        insertTextIntoNode(static_cast<Text *>(node), offset, "\t");
        return Position(node, offset + 1);
    }
    
    // create new tab span
    RefPtr<Element> spanNode = createTabSpanElement(document());
    
    // place it
    if (!node->isTextNode()) {
        insertNodeAt(spanNode.get(), node, offset);
    } else {
        Text *textNode = static_cast<Text *>(node);
        if (offset >= textNode->length()) {
            insertNodeAfter(spanNode.get(), textNode);
        } else {
            // split node to make room for the span
            // NOTE: splitTextNode uses textNode for the
            // second node in the split, so we need to
            // insert the span before it.
            if (offset > 0)
                splitTextNode(textNode, offset);
            insertNodeBefore(spanNode.get(), textNode);
        }
    }
    
    // return the position following the new tab
    return Position(spanNode->lastChild(), spanNode->lastChild()->caretMaxOffset());
}

bool InsertTextCommand::isInsertTextCommand() const
{
    return true;
}

}