/*

 * Copyright (C) 2005 Apple Computer, Inc.  All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY

 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR

 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY

 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 

 */

#include "config.h"

#include "BreakBlockquoteCommand.h"

#include "HTMLElement.h"

#include "HTMLNames.h"

#include "RenderListItem.h"

#include "Text.h"

#include "VisiblePosition.h"

#include "htmlediting.h"

namespace WebCore {

using namespace HTMLNames;

BreakBlockquoteCommand::BreakBlockquoteCommand(Document *document)

    : CompositeEditCommand(document)

{

}

void BreakBlockquoteCommand::doApply()

{

    if (endingSelection().isNone())

        return;

    // Delete the current selection.

    if (endingSelection().isRange())

        deleteSelection(false, false);

    // This is a scenario that should never happen, but we want to

    // make sure we don't dereference a null pointer below.    

    ASSERT(!endingSelection().isNone());

    if (endingSelection().isNone())

        return;

    VisiblePosition visiblePos = endingSelection().visibleStart();

    // pos is a position equivalent to the caret.  We use downstream() so that pos will 

    // be in the first node that we need to move (there are a few exceptions to this, see below).

    Position pos = endingSelection().start().downstream();

    // Find the top-most blockquote from the start.

    Element* topBlockquote = 0;

    for (Node *node = pos.node()->parentNode(); node; node = node->parentNode()) {

        if (isMailBlockquote(node))

            topBlockquote = static_cast<Element*>(node);

    }

    if (!topBlockquote || !topBlockquote->parentNode())

        return;

    RefPtr<Element> breakNode = createBreakElement(document());

    bool isLastVisPosInNode = isLastVisiblePositionInNode(visiblePos, topBlockquote);

    // If the position is at the beginning of the top quoted content, we don't need to break the quote.

    // Instead, insert the break before the blockquote, unless the position is as the end of the the quoted content.

    if (isFirstVisiblePositionInNode(visiblePos, topBlockquote) && !isLastVisPosInNode) {

        insertNodeBefore(breakNode.get(), topBlockquote);

        setEndingSelection(VisibleSelection(Position(breakNode.get(), 0), DOWNSTREAM));

        rebalanceWhitespace();   

        return;

    }

    // Insert a break after the top blockquote.

    insertNodeAfter(breakNode.get(), topBlockquote);

    // If we're inserting the break at the end of the quoted content, we don't need to break the quote.

    if (isLastVisPosInNode) {

        setEndingSelection(VisibleSelection(Position(breakNode.get(), 0), DOWNSTREAM));

        rebalanceWhitespace();

        return;

    }

    // Don't move a line break just after the caret.  Doing so would create an extra, empty paragraph

    // in the new blockquote.

    if (lineBreakExistsAtVisiblePosition(visiblePos))

        pos = pos.next();

    // Adjust the position so we don't split at the beginning of a quote.  

    while (isFirstVisiblePositionInNode(VisiblePosition(pos), nearestMailBlockquote(pos.node())))

        pos = pos.previous();

    // startNode is the first node that we need to move to the new blockquote.

    Node* startNode = pos.node();

    // Split at pos if in the middle of a text node.

    if (startNode->isTextNode()) {

        Text* textNode = static_cast<Text*>(startNode);

        if ((unsigned)pos.deprecatedEditingOffset() >= textNode->length()) {

            startNode = startNode->traverseNextNode();

            ASSERT(startNode);

        } else if (pos.deprecatedEditingOffset() > 0)

            splitTextNode(textNode, pos.deprecatedEditingOffset());

    } else if (pos.deprecatedEditingOffset() > 0) {

        Node* childAtOffset = startNode->childNode(pos.deprecatedEditingOffset());

        startNode = childAtOffset ? childAtOffset : startNode->traverseNextNode();

        ASSERT(startNode);

    }

    // If there's nothing inside topBlockquote to move, we're finished.

    if (!startNode->isDescendantOf(topBlockquote)) {

        setEndingSelection(VisibleSelection(VisiblePosition(Position(startNode, 0))));

        return;

    }

    // Build up list of ancestors in between the start node and the top blockquote.

    Vector<Element*> ancestors;    

    for (Element* node = startNode->parentElement(); node && node != topBlockquote; node = node->parentElement())

        ancestors.append(node);

    // Insert a clone of the top blockquote after the break.

    RefPtr<Element> clonedBlockquote = topBlockquote->cloneElementWithoutChildren();

    insertNodeAfter(clonedBlockquote.get(), breakNode.get());

    // Clone startNode's ancestors into the cloned blockquote.

    // On exiting this loop, clonedAncestor is the lowest ancestor

    // that was cloned (i.e. the clone of either ancestors.last()

    // or clonedBlockquote if ancestors is empty).

    RefPtr<Element> clonedAncestor = clonedBlockquote;

    for (size_t i = ancestors.size(); i != 0; --i) {

        RefPtr<Element> clonedChild = ancestors[i - 1]->cloneElementWithoutChildren();

        // Preserve list item numbering in cloned lists.

        if (clonedChild->isElementNode() && clonedChild->hasTagName(olTag)) {

            Node* listChildNode = i > 1 ? ancestors[i - 2] : startNode;

            // The first child of the cloned list might not be a list item element, 

            // find the first one so that we know where to start numbering.

            while (listChildNode && !listChildNode->hasTagName(liTag))

                listChildNode = listChildNode->nextSibling();

            if (listChildNode && listChildNode->renderer())

                setNodeAttribute(static_cast<Element*>(clonedChild.get()), startAttr, String::number(toRenderListItem(listChildNode->renderer())->value()));

        }

        appendNode(clonedChild.get(), clonedAncestor.get());

        clonedAncestor = clonedChild;

    }

    // Move the startNode and its siblings.

    Node *moveNode = startNode;

    while (moveNode) {

        Node *next = moveNode->nextSibling();

        removeNode(moveNode);

        appendNode(moveNode, clonedAncestor.get());

        moveNode = next;

    }

    if (!ancestors.isEmpty()) {

        // Split the tree up the ancestor chain until the topBlockquote

        // Throughout this loop, clonedParent is the clone of ancestor's parent.

        // This is so we can clone ancestor's siblings and place the clones

        // into the clone corresponding to the ancestor's parent.

        Element* ancestor;

        Element* clonedParent;

        for (ancestor = ancestors.first(), clonedParent = clonedAncestor->parentElement();

             ancestor && ancestor != topBlockquote;

             ancestor = ancestor->parentElement(), clonedParent = clonedParent->parentElement()) {

            moveNode = ancestor->nextSibling();

            while (moveNode) {

                Node *next = moveNode->nextSibling();

                removeNode(moveNode);

                appendNode(moveNode, clonedParent);

                moveNode = next;

            }

        }

        // If the startNode's original parent is now empty, remove it

        Node* originalParent = ancestors.first();

        if (!originalParent->hasChildNodes())

            removeNode(originalParent);

    }

    // Make sure the cloned block quote renders.

    addBlockPlaceholderIfNeeded(clonedBlockquote.get());

    // Put the selection right before the break.

    setEndingSelection(VisibleSelection(Position(breakNode.get(), 0), DOWNSTREAM));

    rebalanceWhitespace();

}

} // namespace WebCore