/* 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/. */

include protocol PBackground;
include protocol PBackgroundSessionStorageManager;
include PBackgroundSharedTypes;

namespace mozilla {
namespace dom {

struct SSSetItemInfo
{
  nsString key;
  nsString value;
};

struct SSRemoveItemInfo
{
  nsString key;
};

struct SSClearInfo
{
};

/**
 * Union of SessionStorage mutation types.
 */
union SSWriteInfo
{
  SSSetItemInfo;
  SSRemoveItemInfo;
  SSClearInfo;
};

struct SSCacheCopy {
  nsCString originKey;
  PrincipalInfo principalInfo;
  SSSetItemInfo[] data;
};

[ChildImpl=virtual, ParentImpl=virtual]
sync protocol PBackgroundSessionStorageCache
{
 manager PBackgroundSessionStorageManager;

 parent:
  async DeleteMe();

  /**
    * Copy SessionStorageCache from the parent process to the content process.
    * See SessionStorageManager documentation for more details.
    *
    * This needs to be synchronous because SessionStorage's semantics are
    * synchronous. Note that the BackgroundSessionStorageManager in the
    * PBackground parent already has the answers to this request immediately
    * available without needing to consult any other threads or perform any I/O.
    */
  sync Load()
       returns (SSSetItemInfo[] aData);

  /**
   * Send changes for SessionStorageCache from a content process to the parent
   * process so that the data in the parent can be updated to be in sync with
   * the content. See SessionStorageManager documentation for more details.
   */
  async Checkpoint(SSWriteInfo[] aWriteInfos);

 child:
   async __delete__();
};

} // namespace dom
} // namespace mozilla