/* -*- Mode: C++; tab-width: 4; 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 _nsCacheDevice_h_
#define _nsCacheDevice_h_

#include "nspr.h"
#include "nsError.h"
#include "nsICache.h"
#include "nsStringFwd.h"

class nsIFile;
class nsCacheEntry;
class nsICacheVisitor;
class nsIInputStream;
class nsIOutputStream;

/******************************************************************************
 * nsCacheDevice
 *******************************************************************************/
class nsCacheDevice {
 public:
  nsCacheDevice() { MOZ_COUNT_CTOR(nsCacheDevice); }
  virtual ~nsCacheDevice() { MOZ_COUNT_DTOR(nsCacheDevice); }

  virtual nsresult Init() = 0;
  virtual nsresult Shutdown() = 0;

  virtual const char *GetDeviceID(void) = 0;
  virtual nsCacheEntry *FindEntry(nsCString *key, bool *collision) = 0;

  virtual nsresult DeactivateEntry(nsCacheEntry *entry) = 0;
  virtual nsresult BindEntry(nsCacheEntry *entry) = 0;
  virtual void DoomEntry(nsCacheEntry *entry) = 0;

  virtual nsresult OpenInputStreamForEntry(nsCacheEntry *entry,
                                           nsCacheAccessMode mode,
                                           uint32_t offset,
                                           nsIInputStream **result) = 0;

  virtual nsresult OpenOutputStreamForEntry(nsCacheEntry *entry,
                                            nsCacheAccessMode mode,
                                            uint32_t offset,
                                            nsIOutputStream **result) = 0;

  virtual nsresult GetFileForEntry(nsCacheEntry *entry, nsIFile **result) = 0;

  virtual nsresult OnDataSizeChange(nsCacheEntry *entry, int32_t deltaSize) = 0;

  virtual nsresult Visit(nsICacheVisitor *visitor) = 0;

  /**
   * Device must evict entries associated with clientID.  If clientID ==
   * nullptr, all entries must be evicted.  Active entries must be doomed,
   * rather than evicted.
   */
  virtual nsresult EvictEntries(const char *clientID) = 0;
};

#endif  // _nsCacheDevice_h_