// Copyright (c) 2008-2009 Nokia Corporation and/or its subsidiary(-ies).
// All rights reserved.
// This component and the accompanying materials are made available
// under the terms of the License "Eclipse Public License v1.0"
// which accompanies this distribution, and is available
// at the URL "http://www.eclipse.org/legal/epl-v10.html".
//
// Initial Contributors:
// Nokia Corporation - initial contribution.
//
// Contributors:
//
// Description:
// f32\sfat32\inc\sl_leafdir_cache.h
// 
//

/**
 @file
 @internalTechnology
*/

//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
//!!
//!! WARNING!! DO NOT edit this file !! '\sfat' component is obsolete and is not being used. '\sfat32'replaces it
//!!
//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!


#ifndef SL_LEAFDIR_CACHE_H
#define SL_LEAFDIR_CACHE_H

//---------------------------------------------------------------------------------------------------------------------------------

class CLeafDirTree;

/*
A data structure to define the location of a direcotry 
*/
class TLeafDirData
    {
public:
    TLeafDirData();
    TLeafDirData(TUint aClusterNum);
    TLeafDirData(TUint aClusterNum, const TEntryPos& aMRUPos);
    inline TBool operator==(const TLeafDirData &aDirPos) const;
    inline TBool operator!=(const TLeafDirData &aDirPos) const;
public:
    TUint       iClusterNum;
    TEntryPos   iMRUPos;
    };

/*
Class definition for the nodes of the leaf dir cache
All cached direcotries are stored as nodes in a tree structure
 
*/
class CLeafDirTreeNode : public CBase
    {
public:
    // Types of the nodes
    enum  TLeafDirTreeNodeType
        {
        ERoot,              // Represents the root node, i.e. the root path
        ELeaf,              // Represents a pure 'leaf' nodes, no child
        ELeafIntermediary,  // Represents a 'leaf' node, but has at least one child
        EPureIntermediary,  // Represents a pure 'intermediary' node, which only exists to share the common path of other nodes
        };

    static CLeafDirTreeNode* NewL(CLeafDirTree* aOwnerTree, const TDesC& aPathName, const TLeafDirData& aDirPos, TLeafDirTreeNodeType aType);
    ~CLeafDirTreeNode();
    inline CLeafDirTreeNode* Parent();
    inline void SetParent(CLeafDirTreeNode* aNode);
    inline RPointerArray<CLeafDirTreeNode>& Children();
    void MakeItChildL(CLeafDirTreeNode* aNode);
    TInt RemoveChild(CLeafDirTreeNode* aNode);
    inline const TLeafDirData& LeafDirData() const;
    inline TUint32 StartClusterNum() const;
    inline void SetLeafDirData(const TLeafDirData& aLeafDirData);
    inline const TDesC& Path() const;
    void SetPathL(const TDesC& aPathData);
    void SetType(const CLeafDirTreeNode::TLeafDirTreeNodeType aType);
    inline TBool IsRoot() const;
    inline TBool IsLeaf();
    inline TBool IsLeafIntermediary();
    inline TBool IsPureIntermediary();

private:
    void ConstructL(CLeafDirTree* aOwnerTree, const TDesC& aPathName);
    CLeafDirTreeNode(const TLeafDirData& aDirPos , TLeafDirTreeNodeType aType);
    CLeafDirTreeNode(const CLeafDirTreeNode& aLeafDirTreeNode);
    CLeafDirTreeNode* operator=(CLeafDirTreeNode& aLeafDirTreeNode);

private:
    CLeafDirTree* iOwnerTree;                   // A pointer to the owner of this node.
    CLeafDirTreeNode* iParent;                  // The parent of this node 
    RPointerArray<CLeafDirTreeNode> iChildren;  // The children of this node
    RBuf iPath;                                 // The path of the direcotry this node represents
    TLeafDirData iLeafDirData;                  // The position of the direcotry this node represents
    TLeafDirTreeNodeType iNodeType;             // The type of the node
    };

/*
Class definition for the tree structure of the leaf dir cache
All cached direcotries are stored as nodes in a tree structure

*/
class CLeafDirTree : public CBase
    {
public:
    static CLeafDirTree* NewL(TUint32 aSize);
    ~CLeafDirTree();

public:
    TInt Search(const TDesC& aPath, CLeafDirTreeNode*& aNodeFound, TLeafDirData& aDirPos); 
    TInt DoSearch(const TDesC& aPath, CLeafDirTreeNode* aNodeToStart, CLeafDirTreeNode*& aNodeFound, TLeafDirData& aDirPos);
    void InsertL(const TDesC& aPath, const TLeafDirData& aDirPos, CLeafDirTreeNode*& aNodeInserted);
    void DoInsertL(CLeafDirTreeNode* aNodeToStart, const TDesC& aPath, const TLeafDirData& aDirPos, CLeafDirTreeNode*& aNodeInserted);
    void RemoveDirL(const TLeafDirData& aDirPos);
    void UpdateMRUPos(const TLeafDirData& aLeafDirData);
    void RemoveFromCacheL(CLeafDirTreeNode* aNodeToDelete);
    CLeafDirTreeNode* FindLeftestLeafNode(CLeafDirTreeNode* aNodeToStart) const;
    void DeleteSubTreeL(CLeafDirTreeNode* aNodeToStart);
    void Reset();
    CLeafDirTreeNode* LruNode();
    void AddOntoLruL(CLeafDirTreeNode* aNodeToAdd);
    TInt RemoveFromLru(CLeafDirTreeNode* aNodeToRemove);
    TInt MakeMostRecentlyUsed(CLeafDirTreeNode* aNodeUsed);
    inline TInt LruCount() const;
    void CheckLimitL();
    
    // For debugging & testing only
    #ifdef _DEBUG
        TInt ObjectCount() const {return iContainer.Count();};
        void AddToObjectContainerL(CLeafDirTreeNode* aNode);
        void RemoveFromObjectContainerL(CLeafDirTreeNode* aNode);
        void DumpTreeContentL() const;
    #endif  //_DEBUG

private:
    void ConstructL();
    CLeafDirTree(TUint32 aSize);

private:
    CLeafDirTreeNode* iRoot;                    // The root node
    RPointerArray<CLeafDirTreeNode> iLruList;   // The list containing all the LRU cached nodes
    TUint32 iSize;                              // The maximum number of items allowed to cache 

    // For debugging & testing only
    #ifdef _DEBUG
        RPointerArray<CLeafDirTreeNode> iContainer; // The container containing all nodes
    #endif  //_DEBUG
    };

/*
Class definition for leaf directory cache.
Acting as an interface class for CFatMountCB to use.

*/
class CLeafDirCache : public CBase
    {
public: 
    static CLeafDirCache* NewL(TUint32 aLimit);
    ~CLeafDirCache();
    void Reset();
    TInt FindInCache(const TDesC& aLeafDirName, TLeafDirData& aDirPos) const; 
    void AddToCacheL(const TDesC& aLeafDirName, const TLeafDirData& aDirPos);
    void RemoveDirL(const TLeafDirData& aDirPos); 
    void UpdateMRUPos(const TLeafDirData& aLeafDirData);
    TInt CacheCount() const;

    // For debugging & testing only
    #ifdef _DEBUG
        void DumpCacheContentL() const;
        TInt NodeCount() const;
    #endif  //_DEBUG

private:
    CLeafDirCache(TUint32 aLimit);
    void ConstructL();

private:
    TUint32 iSize;          // The cache size
    CLeafDirTree* iTree;    // The cache content, represented as a tree structure
    };

//---------------------------------------------------------------------------------------------------------------------------------

#include"sl_leafdir_cache.inl"

#endif //SL_LEAFDIR_CACHE_H