third_party/WebKit/Source/core/layout/LayoutQuote.cpp

/**
 * Copyright (C) 2011 Nokia Inc.  All rights reserved.
 * Copyright (C) 2012 Google 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/layout/LayoutQuote.h"

#include "core/layout/LayoutTextFragment.h"
#include "core/layout/LayoutView.h"
#include "wtf/StdLibExtras.h"
#include "wtf/text/AtomicString.h"

#include <algorithm>

namespace blink {

LayoutQuote::LayoutQuote(Document* node, QuoteType quote)
    : LayoutInline(nullptr),
      m_type(quote),
      m_depth(0),
      m_next(nullptr),
      m_previous(nullptr),
      m_attached(false) {
  setDocumentForAnonymous(node);
}

LayoutQuote::~LayoutQuote() {
  ASSERT(!m_attached);
  ASSERT(!m_next && !m_previous);
}

void LayoutQuote::willBeDestroyed() {
  detachQuote();
  LayoutInline::willBeDestroyed();
}

void LayoutQuote::willBeRemovedFromTree() {
  LayoutInline::willBeRemovedFromTree();
  detachQuote();
}

void LayoutQuote::styleDidChange(StyleDifference diff,
                                 const ComputedStyle* oldStyle) {
  LayoutInline::styleDidChange(diff, oldStyle);
  updateText();
}

struct Language {
  const char* lang;
  UChar open1;
  UChar close1;
  UChar open2;
  UChar close2;
  QuotesData* data;

  bool operator<(const Language& b) const { return strcmp(lang, b.lang) < 0; }
};

// Table of quotes from
// http://www.whatwg.org/specs/web-apps/current-work/multipage/rendering.html#quote
Language languages[] = {
    {"af", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"agq", 0x201e, 0x201d, 0x201a, 0x2019, 0},
    {"ak", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"am", 0x00ab, 0x00bb, 0x2039, 0x203a, 0},
    {"ar", 0x201d, 0x201c, 0x2019, 0x2018, 0},
    {"asa", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"az-cyrl", 0x00ab, 0x00bb, 0x2039, 0x203a, 0},
    {"bas", 0x00ab, 0x00bb, 0x201e, 0x201c, 0},
    {"bem", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"bez", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"bg", 0x201e, 0x201c, 0x201a, 0x2018, 0},
    {"bm", 0x00ab, 0x00bb, 0x201c, 0x201d, 0},
    {"bn", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"br", 0x00ab, 0x00bb, 0x2039, 0x203a, 0},
    {"brx", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"bs-cyrl", 0x201e, 0x201c, 0x201a, 0x2018, 0},
    {"ca", 0x201c, 0x201d, 0x00ab, 0x00bb, 0},
    {"cgg", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"chr", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"cs", 0x201e, 0x201c, 0x201a, 0x2018, 0},
    {"da", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"dav", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"de", 0x201e, 0x201c, 0x201a, 0x2018, 0},
    {"de-ch", 0x00ab, 0x00bb, 0x2039, 0x203a, 0},
    {"dje", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"dua", 0x00ab, 0x00bb, 0x2018, 0x2019, 0},
    {"dyo", 0x00ab, 0x00bb, 0x201c, 0x201d, 0},
    {"dz", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"ebu", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"ee", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"el", 0x00ab, 0x00bb, 0x201c, 0x201d, 0},
    {"en", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"en-gb", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"es", 0x201c, 0x201d, 0x00ab, 0x00bb, 0},
    {"et", 0x201e, 0x201c, 0x201a, 0x2018, 0},
    {"eu", 0x201c, 0x201d, 0x00ab, 0x00bb, 0},
    {"ewo", 0x00ab, 0x00bb, 0x201c, 0x201d, 0},
    {"fa", 0x00ab, 0x00bb, 0x2039, 0x203a, 0},
    {"ff", 0x201e, 0x201d, 0x201a, 0x2019, 0},
    {"fi", 0x201d, 0x201d, 0x2019, 0x2019, 0},
    {"fr", 0x00ab, 0x00bb, 0x00ab, 0x00bb, 0},
    {"fr-ca", 0x00ab, 0x00bb, 0x2039, 0x203a, 0},
    {"fr-ch", 0x00ab, 0x00bb, 0x2039, 0x203a, 0},
    {"gsw", 0x00ab, 0x00bb, 0x2039, 0x203a, 0},
    {"gu", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"guz", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"ha", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"he", 0x0022, 0x0022, 0x0027, 0x0027, 0},
    {"hi", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"hr", 0x201e, 0x201c, 0x201a, 0x2018, 0},
    {"hu", 0x201e, 0x201d, 0x00bb, 0x00ab, 0},
    {"id", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"ig", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"it", 0x00ab, 0x00bb, 0x201c, 0x201d, 0},
    {"ja", 0x300c, 0x300d, 0x300e, 0x300f, 0},
    {"jgo", 0x00ab, 0x00bb, 0x2039, 0x203a, 0},
    {"jmc", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"kab", 0x00ab, 0x00bb, 0x201c, 0x201d, 0},
    {"kam", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"kde", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"kea", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"khq", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"ki", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"kkj", 0x00ab, 0x00bb, 0x2039, 0x203a, 0},
    {"kln", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"km", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"kn", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"ko", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"ksb", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"ksf", 0x00ab, 0x00bb, 0x2018, 0x2019, 0},
    {"lag", 0x201d, 0x201d, 0x2019, 0x2019, 0},
    {"lg", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"ln", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"lo", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"lt", 0x201e, 0x201c, 0x201e, 0x201c, 0},
    {"lu", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"luo", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"luy", 0x201e, 0x201c, 0x201a, 0x2018, 0},
    {"lv", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"mas", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"mer", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"mfe", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"mg", 0x00ab, 0x00bb, 0x201c, 0x201d, 0},
    {"mgo", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"mk", 0x201e, 0x201c, 0x201a, 0x2018, 0},
    {"ml", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"mr", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"ms", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"mua", 0x00ab, 0x00bb, 0x201c, 0x201d, 0},
    {"my", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"naq", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"nb", 0x00ab, 0x00bb, 0x2018, 0x2019, 0},
    {"nd", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"nl", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"nmg", 0x201e, 0x201d, 0x00ab, 0x00bb, 0},
    {"nn", 0x00ab, 0x00bb, 0x2018, 0x2019, 0},
    {"nnh", 0x00ab, 0x00bb, 0x201c, 0x201d, 0},
    {"nus", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"nyn", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"pl", 0x201e, 0x201d, 0x00ab, 0x00bb, 0},
    {"pt", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"pt-pt", 0x00ab, 0x00bb, 0x201c, 0x201d, 0},
    {"rn", 0x201d, 0x201d, 0x2019, 0x2019, 0},
    {"ro", 0x201e, 0x201d, 0x00ab, 0x00bb, 0},
    {"rof", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"ru", 0x00ab, 0x00bb, 0x201e, 0x201c, 0},
    {"rw", 0x00ab, 0x00bb, 0x2018, 0x2019, 0},
    {"rwk", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"saq", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"sbp", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"seh", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"ses", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"sg", 0x00ab, 0x00bb, 0x201c, 0x201d, 0},
    {"shi", 0x00ab, 0x00bb, 0x201e, 0x201d, 0},
    {"shi-tfng", 0x00ab, 0x00bb, 0x201e, 0x201d, 0},
    {"si", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"sk", 0x201e, 0x201c, 0x201a, 0x2018, 0},
    {"sl", 0x201e, 0x201c, 0x201a, 0x2018, 0},
    {"sn", 0x201d, 0x201d, 0x2019, 0x2019, 0},
    {"so", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"sq", 0x201e, 0x201c, 0x201a, 0x2018, 0},
    {"sr", 0x201e, 0x201c, 0x201a, 0x2018, 0},
    {"sr-latn", 0x201e, 0x201c, 0x201a, 0x2018, 0},
    {"sv", 0x201d, 0x201d, 0x2019, 0x2019, 0},
    {"sw", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"swc", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"ta", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"te", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"teo", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"th", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"ti-er", 0x2018, 0x2019, 0x201c, 0x201d, 0},
    {"to", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"tr", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"twq", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"tzm", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"uk", 0x00ab, 0x00bb, 0x201e, 0x201c, 0},
    {"ur", 0x201d, 0x201c, 0x2019, 0x2018, 0},
    {"vai", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"vai-latn", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"vi", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"vun", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"xh", 0x2018, 0x2019, 0x201c, 0x201d, 0},
    {"xog", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"yav", 0x00ab, 0x00bb, 0x00ab, 0x00bb, 0},
    {"yo", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"zh", 0x201c, 0x201d, 0x2018, 0x2019, 0},
    {"zh-hant", 0x300c, 0x300d, 0x300e, 0x300f, 0},
    {"zu", 0x201c, 0x201d, 0x2018, 0x2019, 0},
};

const QuotesData* quotesDataForLanguage(const AtomicString& lang) {
  if (lang.isNull())
    return nullptr;

  // This could be just a hash table, but doing that adds 200k to LayoutQuote.o
  Language* languagesEnd = languages + WTF_ARRAY_LENGTH(languages);
  CString lowercaseLang = lang.lower().utf8();
  Language key = {lowercaseLang.data(), 0, 0, 0, 0, 0};
  Language* match = std::lower_bound(languages, languagesEnd, key);
  if (match == languagesEnd || strcmp(match->lang, key.lang))
    return nullptr;

  if (!match->data)
    match->data = QuotesData::create(match->open1, match->close1, match->open2,
                                     match->close2)
                      .leakRef();

  return match->data;
}

static const QuotesData* basicQuotesData() {
  // FIXME: The default quotes should be the fancy quotes for "en".
  DEFINE_STATIC_REF(QuotesData, staticBasicQuotes,
                    (QuotesData::create('"', '"', '\'', '\'')));
  return staticBasicQuotes;
}

void LayoutQuote::updateText() {
  String text = computeText();
  if (m_text == text)
    return;

  m_text = text;

  LayoutTextFragment* fragment = findFragmentChild();
  if (fragment) {
    fragment->setStyle(mutableStyle());
    fragment->setContentString(m_text.impl());
  } else {
    fragment = new LayoutTextFragment(&document(), m_text.impl());
    fragment->setStyle(mutableStyle());
    addChild(fragment);
  }
}

LayoutTextFragment* LayoutQuote::findFragmentChild() const {
  // We walk from the end of the child list because, if we've had a first-letter
  // LayoutObject inserted then the remaining text will be at the end.
  while (LayoutObject* child = lastChild()) {
    if (child->isText() && toLayoutText(child)->isTextFragment())
      return toLayoutTextFragment(child);
  }

  return nullptr;
}

String LayoutQuote::computeText() const {
  switch (m_type) {
    case NO_OPEN_QUOTE:
    case NO_CLOSE_QUOTE:
      return emptyString();
    case CLOSE_QUOTE:
      return quotesData()->getCloseQuote(m_depth - 1).impl();
    case OPEN_QUOTE:
      return quotesData()->getOpenQuote(m_depth).impl();
  }
  ASSERT_NOT_REACHED();
  return emptyString();
}

const QuotesData* LayoutQuote::quotesData() const {
  if (const QuotesData* customQuotes = style()->quotes())
    return customQuotes;

  if (const QuotesData* quotes = quotesDataForLanguage(style()->locale()))
    return quotes;

  return basicQuotesData();
}

void LayoutQuote::attachQuote() {
  ASSERT(view());
  ASSERT(!m_attached);
  ASSERT(!m_next && !m_previous);
  ASSERT(isRooted());

  if (!view()->layoutQuoteHead()) {
    view()->setLayoutQuoteHead(this);
    m_attached = true;
    return;
  }

  for (LayoutObject* predecessor = previousInPreOrder(); predecessor;
       predecessor = predecessor->previousInPreOrder()) {
    // Skip unattached predecessors to avoid having stale m_previous pointers
    // if the previous node is never attached and is then destroyed.
    if (!predecessor->isQuote() || !toLayoutQuote(predecessor)->isAttached())
      continue;
    m_previous = toLayoutQuote(predecessor);
    m_next = m_previous->m_next;
    m_previous->m_next = this;
    if (m_next)
      m_next->m_previous = this;
    break;
  }

  if (!m_previous) {
    m_next = view()->layoutQuoteHead();
    view()->setLayoutQuoteHead(this);
    if (m_next)
      m_next->m_previous = this;
  }
  m_attached = true;

  for (LayoutQuote* quote = this; quote; quote = quote->m_next)
    quote->updateDepth();

  ASSERT(!m_next || m_next->m_attached);
  ASSERT(!m_next || m_next->m_previous == this);
  ASSERT(!m_previous || m_previous->m_attached);
  ASSERT(!m_previous || m_previous->m_next == this);
}

void LayoutQuote::detachQuote() {
  ASSERT(!m_next || m_next->m_attached);
  ASSERT(!m_previous || m_previous->m_attached);
  if (!m_attached)
    return;

  // Reset our attached status at this point because it's possible for
  // updateDepth() to call into attachQuote(). Attach quote walks the layout
  // tree looking for quotes that are attached and does work on them.
  m_attached = false;

  if (m_previous)
    m_previous->m_next = m_next;
  else if (view())
    view()->setLayoutQuoteHead(m_next);
  if (m_next)
    m_next->m_previous = m_previous;
  if (!documentBeingDestroyed()) {
    for (LayoutQuote* quote = m_next; quote; quote = quote->m_next)
      quote->updateDepth();
  }
  m_next = nullptr;
  m_previous = nullptr;
  m_depth = 0;
}

void LayoutQuote::updateDepth() {
  ASSERT(m_attached);
  int oldDepth = m_depth;
  m_depth = 0;
  if (m_previous) {
    m_depth = m_previous->m_depth;
    switch (m_previous->m_type) {
      case OPEN_QUOTE:
      case NO_OPEN_QUOTE:
        m_depth++;
        break;
      case CLOSE_QUOTE:
      case NO_CLOSE_QUOTE:
        if (m_depth)
          m_depth--;
        break;
    }
  }
  if (oldDepth != m_depth)
    updateText();
}

}  // namespace blink