/*
 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
 *           (C) 1999 Antti Koivisto (koivisto@kde.org)
 * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2013 Apple Inc. All
 * rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

#include "core/dom/CharacterData.h"

#include "bindings/core/v8/ExceptionState.h"
#include "core/dom/Document.h"
#include "core/dom/ExceptionCode.h"
#include "core/dom/MutationObserverInterestGroup.h"
#include "core/dom/MutationRecord.h"
#include "core/dom/ProcessingInstruction.h"
#include "core/dom/Text.h"
#include "core/editing/FrameSelection.h"
#include "core/events/MutationEvent.h"
#include "core/inspector/InspectorInstrumentation.h"
#include "wtf/CheckedNumeric.h"

namespace blink {

void CharacterData::atomize() {
  m_data = AtomicString(m_data);
}

void CharacterData::setData(const String& data) {
  const String& nonNullData = !data.isNull() ? data : emptyString();
  if (m_data == nonNullData)
    return;

  unsigned oldLength = length();

  setDataAndUpdate(nonNullData, 0, oldLength, nonNullData.length(),
                   UpdateFromNonParser);
  document().didRemoveText(this, 0, oldLength);
}

String CharacterData::substringData(unsigned offset,
                                    unsigned count,
                                    ExceptionState& exceptionState) {
  if (offset > length()) {
    exceptionState.throwDOMException(
        IndexSizeError, "The offset " + String::number(offset) +
                            " is greater than the node's length (" +
                            String::number(length()) + ").");
    return String();
  }

  return m_data.substring(offset, count);
}

void CharacterData::parserAppendData(const String& data) {
  String newStr = m_data + data;

  setDataAndUpdate(newStr, m_data.length(), 0, data.length(), UpdateFromParser);
}

void CharacterData::appendData(const String& data) {
  String newStr = m_data + data;

  setDataAndUpdate(newStr, m_data.length(), 0, data.length(),
                   UpdateFromNonParser);

  // FIXME: Should we call textInserted here?
}

void CharacterData::insertData(unsigned offset,
                               const String& data,
                               ExceptionState& exceptionState) {
  if (offset > length()) {
    exceptionState.throwDOMException(
        IndexSizeError, "The offset " + String::number(offset) +
                            " is greater than the node's length (" +
                            String::number(length()) + ").");
    return;
  }

  String newStr = m_data;
  newStr.insert(data, offset);

  setDataAndUpdate(newStr, offset, 0, data.length(), UpdateFromNonParser);

  document().didInsertText(this, offset, data.length());
}

static bool validateOffsetCount(unsigned offset,
                                unsigned count,
                                unsigned length,
                                unsigned& realCount,
                                ExceptionState& exceptionState) {
  if (offset > length) {
    exceptionState.throwDOMException(
        IndexSizeError, "The offset " + String::number(offset) +
                            " is greater than the node's length (" +
                            String::number(length) + ").");
    return false;
  }

  CheckedNumeric<unsigned> offsetCount = offset;
  offsetCount += count;

  if (!offsetCount.IsValid() || offset + count > length)
    realCount = length - offset;
  else
    realCount = count;

  return true;
}

void CharacterData::deleteData(unsigned offset,
                               unsigned count,
                               ExceptionState& exceptionState) {
  unsigned realCount = 0;
  if (!validateOffsetCount(offset, count, length(), realCount, exceptionState))
    return;

  String newStr = m_data;
  newStr.remove(offset, realCount);

  setDataAndUpdate(newStr, offset, realCount, 0, UpdateFromNonParser);

  document().didRemoveText(this, offset, realCount);
}

void CharacterData::replaceData(unsigned offset,
                                unsigned count,
                                const String& data,
                                ExceptionState& exceptionState) {
  unsigned realCount = 0;
  if (!validateOffsetCount(offset, count, length(), realCount, exceptionState))
    return;

  String newStr = m_data;
  newStr.remove(offset, realCount);
  newStr.insert(data, offset);

  setDataAndUpdate(newStr, offset, realCount, data.length(),
                   UpdateFromNonParser);

  // update the markers for spell checking and grammar checking
  document().didRemoveText(this, offset, realCount);
  document().didInsertText(this, offset, data.length());
}

String CharacterData::nodeValue() const {
  return m_data;
}

bool CharacterData::containsOnlyWhitespace() const {
  return m_data.containsOnlyWhitespace();
}

void CharacterData::setNodeValue(const String& nodeValue) {
  setData(nodeValue);
}

void CharacterData::setDataAndUpdate(const String& newData,
                                     unsigned offsetOfReplacedData,
                                     unsigned oldLength,
                                     unsigned newLength,
                                     UpdateSource source) {
  if (source != UpdateFromParser)
    document().dataWillChange(*this);

  String oldData = m_data;
  m_data = newData;

  DCHECK(!layoutObject() || isTextNode());
  if (isTextNode())
    toText(this)->updateTextLayoutObject(offsetOfReplacedData, oldLength);

  if (source != UpdateFromParser) {
    if (getNodeType() == kProcessingInstructionNode)
      toProcessingInstruction(this)->didAttributeChanged();

    document().notifyUpdateCharacterData(this, offsetOfReplacedData, oldLength,
                                         newLength);

    if (document().frame())
      document().frame()->selection().didUpdateCharacterData(
          this, offsetOfReplacedData, oldLength, newLength);
  }

  document().incDOMTreeVersion();
  didModifyData(oldData, source);
}

void CharacterData::didModifyData(const String& oldData, UpdateSource source) {
  if (MutationObserverInterestGroup* mutationRecipients =
          MutationObserverInterestGroup::createForCharacterDataMutation(*this))
    mutationRecipients->enqueueMutationRecord(
        MutationRecord::createCharacterData(this, oldData));

  if (parentNode()) {
    ContainerNode::ChildrenChange change = {
        ContainerNode::TextChanged, this, previousSibling(), nextSibling(),
        ContainerNode::ChildrenChangeSourceAPI};
    parentNode()->childrenChanged(change);
  }

  // Skip DOM mutation events if the modification is from parser.
  // Note that mutation observer events will still fire.
  // Spec: https://html.spec.whatwg.org/multipage/syntax.html#insert-a-character
  if (source != UpdateFromParser && !isInShadowTree()) {
    if (document().hasListenerType(Document::DOMCHARACTERDATAMODIFIED_LISTENER))
      dispatchScopedEvent(
          MutationEvent::create(EventTypeNames::DOMCharacterDataModified, true,
                                nullptr, oldData, m_data));
    dispatchSubtreeModifiedEvent();
  }
  InspectorInstrumentation::characterDataModified(this);
}

int CharacterData::maxCharacterOffset() const {
  return static_cast<int>(length());
}

}  // namespace blink