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

/* vim:set ts=2 sw=2 sts=2 et cindent: */

/* 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/. */

#if !defined(MediaSystemResourceService_h_)

#define MediaSystemResourceService_h_

#include <deque>

#include "MediaSystemResourceTypes.h"

#include "mozilla/StaticPtr.h"

#include "nsClassHashtable.h"

namespace mozilla {

namespace media {

class MediaSystemResourceManagerParent;

} // namespace media

/**

 * Manage media system resource allocation requests within system.

 */

class MediaSystemResourceService

{

public:

  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(MediaSystemResourceService)

  static MediaSystemResourceService* Get();

  static void Init();

  static void Shutdown();

  void Acquire(media::MediaSystemResourceManagerParent* aParent,

               uint32_t aId,

               MediaSystemResourceType aResourceType,

               bool aWillWait);

  void ReleaseResource(media::MediaSystemResourceManagerParent* aParent,

                       uint32_t aId,

                       MediaSystemResourceType aResourceType);

  void ReleaseResource(media::MediaSystemResourceManagerParent* aParent);

private:

  MediaSystemResourceService();

  ~MediaSystemResourceService();

  struct MediaSystemResourceRequest {

    MediaSystemResourceRequest()

      : mParent(nullptr), mId(-1) {}

    MediaSystemResourceRequest(media::MediaSystemResourceManagerParent* aParent, uint32_t aId)

      : mParent(aParent), mId(aId) {}

    media::MediaSystemResourceManagerParent* mParent;

    uint32_t mId;

  };

  struct MediaSystemResource {

    MediaSystemResource()

      : mResourceCount(0) {}

    explicit MediaSystemResource(uint32_t aResourceCount)

      : mResourceCount(aResourceCount) {}

    std::deque<MediaSystemResourceRequest> mWaitingRequests;

    std::deque<MediaSystemResourceRequest> mAcquiredRequests;

    uint32_t mResourceCount;

  };

  void Destroy();

  void RemoveRequest(media::MediaSystemResourceManagerParent* aParent,

                     uint32_t aId,

                     MediaSystemResourceType aResourceType);

  void RemoveRequests(media::MediaSystemResourceManagerParent* aParent,

                      MediaSystemResourceType aResourceType);

  void UpdateRequests(MediaSystemResourceType aResourceType);

  bool mDestroyed;

  nsClassHashtable<nsUint32HashKey, MediaSystemResource> mResources;

  static StaticRefPtr<MediaSystemResourceService> sSingleton;

};

} // namespace mozilla

#endif