/* -*- Mode: C++; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_net_MemoryDownloader_h__

#define mozilla_net_MemoryDownloader_h__

#include "mozilla/UniquePtr.h"

#include "nsCOMPtr.h"

#include "nsIStreamListener.h"

#include "nsTArray.h"

/**

 * mozilla::net::MemoryDownloader

 *

 * This class is similar to nsIDownloader, but stores the downloaded

 * stream in memory instead of a file.  Ownership of the temporary

 * memory is transferred to the observer when download is complete;

 * there is no need to retain a reference to the downloader.

 */

namespace mozilla {

namespace net {

class MemoryDownloader final : public nsIStreamListener

{

public:

  NS_DECL_ISUPPORTS

  NS_DECL_NSIREQUESTOBSERVER

  NS_DECL_NSISTREAMLISTENER

  typedef mozilla::UniquePtr<FallibleTArray<uint8_t>> Data;

  class IObserver : public nsISupports {

  public:

    // Note: aData may be null if (and only if) aStatus indicates failure.

    virtual void OnDownloadComplete(MemoryDownloader* aDownloader,

                                    nsIRequest* aRequest,

                                    nsISupports* aCtxt,

                                    nsresult aStatus,

                                    Data aData) = 0;

  };

  explicit MemoryDownloader(IObserver* aObserver);

private:

  virtual ~MemoryDownloader() = default;

  static nsresult ConsumeData(nsIInputStream *in,

                              void           *closure,

                              const char     *fromRawSegment,

                              uint32_t        toOffset,

                              uint32_t        count,

                              uint32_t       *writeCount);

  RefPtr<IObserver> mObserver;

  Data mData;

  nsresult mStatus;

};

} // namespace net

} // namespace mozilla

#endif // mozilla_net_MemoryDownloader_h__