text: // -------------------------------------------------
  // BlinKit - BlinKit Library
  // -------------------------------------------------
  //   File Name: BlobData.cpp
  // Description: BlobData Class
  //      Author: Ziming Li
  //     Created: 2021-07-27
  // -------------------------------------------------
  // Copyright (C) 2021 MingYang Software Technology.
  // -------------------------------------------------
  
  /*
   * Copyright (C) 2010 Google 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:
   *
   *     * Redistributions of source code must retain the above copyright
   * notice, this list of conditions and the following disclaimer.
   *     * 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.
   *     * Neither the name of Google Inc. nor the names of its
   * contributors may be used to endorse or promote products derived from
   * this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "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 THE COPYRIGHT
   * OWNER 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 "platform/blob/BlobData.h"
  
  #include "platform/UUID.h"
  // BKTODO: #include "platform/blob/BlobRegistry.h"
  #include "platform/text/LineEnding.h"
  #include "wtf/OwnPtr.h"
  #include "wtf/PassRefPtr.h"
  #include "wtf/RefPtr.h"
  #include "wtf/Vector.h"
  #include "wtf/text/CString.h"
  #include "wtf/text/TextEncoding.h"
  
  namespace blink {
  
  namespace {
  
  // All consecutive items that are accumulate to < this number will have the
  // data appended to the same item.
  static const size_t kMaxConsolidatedItemSizeInBytes = 15 * 1024;
  
  // http://dev.w3.org/2006/webapi/FileAPI/#constructorBlob
  bool isValidBlobType(const String& type)
  {
      for (unsigned i = 0; i < type.length(); ++i) {
          UChar c = type[i];
          if (c < 0x20 || c > 0x7E)
              return false;
      }
      return true;
  }
  
  }
  
  const long long BlobDataItem::toEndOfFile = -1;
  
  RawData::RawData()
  {
  }
  
  void RawData::detachFromCurrentThread()
  {
  }
  
  void BlobDataItem::detachFromCurrentThread()
  {
      data->detachFromCurrentThread();
      path = path.isolatedCopy();
      ASSERT(false); // BKTODO: fileSystemURL = fileSystemURL.copy();
  }
  
  PassOwnPtr<BlobData> BlobData::create()
  {
      return adoptPtr(new BlobData());
  }
  
  void BlobData::detachFromCurrentThread()
  {
      m_contentType = m_contentType.isolatedCopy();
      for (size_t i = 0; i < m_items.size(); ++i)
          m_items.at(i).detachFromCurrentThread();
  }
  
  void BlobData::setContentType(const String& contentType)
  {
      if (isValidBlobType(contentType))
          m_contentType = contentType;
      else
          m_contentType = "";
  }
  
  void BlobData::appendData(PassRefPtr<RawData> data, long long offset, long long length)
  {
      m_items.append(BlobDataItem(data, offset, length));
  }
  
  void BlobData::appendFile(const String& path)
  {
      m_items.append(BlobDataItem(path));
  }
  
  void BlobData::appendFile(const String& path, long long offset, long long length, double expectedModificationTime)
  {
      m_items.append(BlobDataItem(path, offset, length, expectedModificationTime));
  }
  
  void BlobData::appendBlob(PassRefPtr<BlobDataHandle> dataHandle, long long offset, long long length)
  {
      m_items.append(BlobDataItem(dataHandle, offset, length));
  }
  
  void BlobData::appendFileSystemURL(const KURL& url, long long offset, long long length, double expectedModificationTime)
  {
      m_items.append(BlobDataItem(url, offset, length, expectedModificationTime));
  }
  
  void BlobData::appendText(const String& text, bool doNormalizeLineEndingsToNative)
  {
      CString utf8Text = UTF8Encoding().encode(text, WTF::EntitiesForUnencodables);
      RefPtr<RawData> data = nullptr;
      Vector<char>* buffer;
      if (canConsolidateData(text.length())) {
          buffer = m_items.last().data->mutableData();
      } else {
          data = RawData::create();
          buffer = data->mutableData();
      }
  
      if (doNormalizeLineEndingsToNative) {
          normalizeLineEndingsToNative(utf8Text, *buffer);
      } else {
          buffer->append(utf8Text.data(), utf8Text.length());
      }
  
      if (data)
          m_items.append(BlobDataItem(data.release()));
  }
  
  void BlobData::appendBytes(const void* bytes, size_t length)
  {
      if (canConsolidateData(length)) {
          m_items.last().data->mutableData()->append(
              static_cast<const char*>(bytes),
              length);
          return;
      }
      RefPtr<RawData> data = RawData::create();
      Vector<char>* buffer = data->mutableData();
      buffer->append(static_cast<const char *>(bytes), length);
      m_items.append(BlobDataItem(data.release()));
  }
  
  long long BlobData::length() const
  {
      long long length = 0;
  
      for (Vector<BlobDataItem>::const_iterator it = m_items.begin(); it != m_items.end(); ++it) {
          const BlobDataItem& item = *it;
          if (item.length != BlobDataItem::toEndOfFile) {
              ASSERT(item.length >= 0);
              length += item.length;
              continue;
          }
  
          switch (item.type) {
          case BlobDataItem::Data:
              length += item.data->length();
              break;
          case BlobDataItem::File:
          case BlobDataItem::Blob:
          case BlobDataItem::FileSystemURL:
              return BlobDataItem::toEndOfFile;
          }
      }
      return length;
  }
  
  bool BlobData::canConsolidateData(size_t length)
  {
      if (m_items.isEmpty())
          return false;
      BlobDataItem& lastItem = m_items.last();
      if (lastItem.type != BlobDataItem::Data)
          return false;
      if (lastItem.data->length() + length > kMaxConsolidatedItemSizeInBytes)
          return false;
      return true;
  }
  
  BlobDataHandle::BlobDataHandle()
      : m_uuid(createCanonicalUUIDString())
      , m_size(0)
  {
      ASSERT(false); // BKTODO: BlobRegistry::registerBlobData(m_uuid, BlobData::create());
  }
  
  BlobDataHandle::BlobDataHandle(PassOwnPtr<BlobData> data, long long size)
      : m_uuid(createCanonicalUUIDString())
      , m_type(data->contentType().isolatedCopy())
      , m_size(size)
  {
      ASSERT(false); // BKTODO: BlobRegistry::registerBlobData(m_uuid, std::move(data));
  }
  
  BlobDataHandle::BlobDataHandle(const String& uuid, const String& type, long long size)
      : m_uuid(uuid.isolatedCopy())
      , m_type(isValidBlobType(type) ? type.isolatedCopy() : "")
      , m_size(size)
  {
      ASSERT(false); // BKTODO: BlobRegistry::addBlobDataRef(m_uuid);
  }
  
  BlobDataHandle::~BlobDataHandle()
  {
      ASSERT(false); // BKTODO: BlobRegistry::removeBlobDataRef(m_uuid);
  }
  
  } // namespace blink
  