/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-

 *

 * 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 _nsDiskCacheDevice_h_

#define _nsDiskCacheDevice_h_

#include "mozilla/MemoryReporting.h"

#include "nsCacheDevice.h"

#include "nsDiskCacheBinding.h"

#include "nsDiskCacheBlockFile.h"

#include "nsDiskCacheEntry.h"

#include "nsIFile.h"

#include "nsIObserver.h"

#include "nsCOMArray.h"

class nsDiskCacheMap;

class nsDiskCacheDevice final : public nsCacheDevice {

public:

    nsDiskCacheDevice();

    virtual ~nsDiskCacheDevice();

    virtual nsresult        Init() override;

    virtual nsresult        Shutdown() override;

    virtual const char *    GetDeviceID(void) override;

    virtual nsCacheEntry *  FindEntry(nsCString * key, bool *collision) override;

    virtual nsresult        DeactivateEntry(nsCacheEntry * entry) override;

    virtual nsresult        BindEntry(nsCacheEntry * entry) override;

    virtual void            DoomEntry( nsCacheEntry * entry ) override;

    virtual nsresult OpenInputStreamForEntry(nsCacheEntry *    entry,

                                             nsCacheAccessMode mode,

                                             uint32_t          offset,

                                             nsIInputStream ** result) override;

    virtual nsresult OpenOutputStreamForEntry(nsCacheEntry *     entry,

                                              nsCacheAccessMode  mode,

                                              uint32_t           offset,

                                              nsIOutputStream ** result) override;

    virtual nsresult        GetFileForEntry(nsCacheEntry *    entry,

                                            nsIFile **        result) override;

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

    virtual nsresult        Visit(nsICacheVisitor * visitor) override;

    virtual nsresult        EvictEntries(const char * clientID) override;

    bool                    EntryIsTooBig(int64_t entrySize);

    size_t                 SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf);

    /**

     * Preference accessors

     */

    void                    SetCacheParentDirectory(nsIFile * parentDir);

    void                    SetCapacity(uint32_t  capacity);

    void                    SetMaxEntrySize(int32_t  maxSizeInKilobytes);

/* private: */

    void                    getCacheDirectory(nsIFile ** result);

    uint32_t                getCacheCapacity();

    uint32_t                getCacheSize();

    uint32_t                getEntryCount();

    nsDiskCacheMap *        CacheMap()    { return &mCacheMap; }

private:

    friend class nsDiskCacheDeviceDeactivateEntryEvent;

    friend class nsEvictDiskCacheEntriesEvent;

    friend class nsDiskCacheMap;

    /**

     *  Private methods

     */

    inline bool IsValidBinding(nsDiskCacheBinding *binding)

    {

        NS_ASSERTION(binding, "  binding == nullptr");

        NS_ASSERTION(binding->mDeactivateEvent == nullptr,

                     "  entry in process of deactivation");

        return (binding && !binding->mDeactivateEvent);

    }

    bool                    Initialized() { return mInitialized; }

    nsresult                Shutdown_Private(bool flush);

    nsresult                DeactivateEntry_Private(nsCacheEntry * entry,

                                                    nsDiskCacheBinding * binding);

    nsresult                OpenDiskCache();

    nsresult                ClearDiskCache();

    nsresult                EvictDiskCacheEntries(uint32_t  targetCapacity);

    /**

     *  Member variables

     */

    nsCOMPtr<nsIFile>       mCacheDirectory;

    nsDiskCacheBindery      mBindery;

    uint32_t                mCacheCapacity;     // Unit is KiB's

    int32_t                 mMaxEntrySize;      // Unit is bytes internally

    // XXX need soft/hard limits, currentTotal

    nsDiskCacheMap          mCacheMap;

    bool                    mInitialized;

    bool                    mClearingDiskCache;

};

#endif // _nsDiskCacheDevice_h_