// Copyright (c) 2007-2009 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// under the terms of "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:

// CMSVCACHEINDEXTABLEENTRY.CPP

// HEADER FILES

// 

//

#include "msvcacheindextableentry.h"

#include "msventryfreepool.h"

#include "msvcacheentry.h"

#if (defined SYMBIAN_MSGS_ENHANCED_REMOVABLE_MEDIA_SUPPORT)	

	#include "msvindexadapter.h"

#endif

/**

 * FUNCTION DEFINITION

 */

//****************************

//CMsvCacheIndexTableEntry

//****************************

/**

 * NewL()

 * @param None.

 * @return The newly created index table entry

 * 

 * It returns an instance of the CMsvCacheIndexTableEntry class, i.e. a newly 

 * constructed index table with no entries in it.

 */

CMsvCacheIndexTableEntry* CMsvCacheIndexTableEntry::NewL()

	{

	CMsvCacheIndexTableEntry *self = new(ELeave) CMsvCacheIndexTableEntry();

	return self;

	}

/**

 * NewL()

 * @param CMsvCacheEntry& : a new cache entry

 * @return The newly created index table entry

 * 

 * It returns an instance of the CMsvCacheIndexTableEntry class with the passed entry

 * added.

 */

CMsvCacheIndexTableEntry* CMsvCacheIndexTableEntry::NewL(CMsvCacheEntry*& aEntry)

	{

	CMsvCacheIndexTableEntry *self = CMsvCacheIndexTableEntry::NewLC(aEntry);

	CleanupStack::Pop();

	return self;

	}

/**

 * NewLC()

 * @param CMsvCacheEntry& : a new cache entry

 * @return The newly created index table entry

 * 

 * It returns an instance of the CMsvCacheIndexTableEntry class 

 * with the passed entry added. It leaves the object into cleanup stack.

 */

CMsvCacheIndexTableEntry* CMsvCacheIndexTableEntry::NewLC(CMsvCacheEntry*& aEntry)

	{

	CMsvCacheIndexTableEntry *self = new(ELeave) CMsvCacheIndexTableEntry();

	CleanupStack::PushL(self);

	self->AddEntryL(aEntry);

	return self;

	}

/**

 * NewL()

 * @param RPointerArrayCMsvCacheEntry>& : RPointerArray reference to child entries

 * @return The newly created index table entry

 * 

 * It returns an instance of the CMsvCacheIndexTableEntry class filled with child

 * entries.

 */

CMsvCacheIndexTableEntry* CMsvCacheIndexTableEntry::NewL(RPointerArray<CMsvCacheEntry>& aEntries, TInt aInitIndex /*(DEFALUT=0)*/, TInt aCount /* DEFAULT = -1*/)

	{

	CMsvCacheIndexTableEntry *self = CMsvCacheIndexTableEntry::NewLC(aEntries, aInitIndex, aCount);

	CleanupStack::Pop();

	return self;

	}

/**

 * NewLC()

 * @param RPointerArrayCMsvCacheEntry>& : RPointerArray reference to child entries

 * @return The newly created index table entry

 * 

 * It returns an instance of the CMsvCacheIndexTableEntry class filled with child

 * entries. It leaves the object into cleanup stack.

 */

CMsvCacheIndexTableEntry* CMsvCacheIndexTableEntry::NewLC(RPointerArray<CMsvCacheEntry>& aEntries, TInt aInitIndex /*(DEFALUT=0)*/, TInt aCount /* DEFAULT = -1*/)

	{

	CMsvCacheIndexTableEntry *self = new(ELeave) CMsvCacheIndexTableEntry();

	CleanupStack::PushL(self);

	self->AddEntrySetL(aEntries, aInitIndex, aCount);

	return self;

	}

/**

 * CMsvCacheIndexTableEntry()

 * @param None.

 * @return None.

 * 

 * Constructor

 */

CMsvCacheIndexTableEntry::CMsvCacheIndexTableEntry()

:iMinMsvId(0), iMaxMsvId(0), iFlags(EMsvCacheIndexTableClearFlag)

	{

	iTimeStamp.HomeTime(); //set the timestamp to number of seconds since Epoc.

	iBlockPtr = NULL;

	}

/**

 * ~CMsvCacheIndexTableEntry()

 * @param None.

 * @return None.

 * 

 * Destructor - releases the block to the cache free pool and sets it to NULL.

 */

CMsvCacheIndexTableEntry::~CMsvCacheIndexTableEntry()

	{

	//destructor should delete everything no matter if entries are locked or not

	ReleaseBlock(ETrue);

	}

/**

 * AddEntryL()

 * @param CMsvCacheEntry& : reference to the CMsvCacheEntry to be added.

 * @return None.

 * 

 * The function adds an entry into the index table. The entity who passes the entry

 * to the function will give up ownership of the same and hence cannot modify or 

 * delete it.

 * 1. If the block is NULL, it creates a new one and appends the entry to the block

 *    and accordingly sets the TMsvId ranges.

 * 2. If block is not NULL, then append the entry to it.

 * 	2.1 If the entry already exists in the block then release the old entry from the block and

 *		append the new one.

 * 	2.2 If the entry fits only at the end of the last block then we need to change

 *      the iMaxMsvid.

 *      If the indextable has not been created and if the folder has just one block, and this block contains

 * 		random entries, then we may need to set the iMinMsvId.

 */

void CMsvCacheIndexTableEntry::AddEntryL(CMsvCacheEntry*& aEntry, TBool aReplace /* DEFAULT = EFalse*/)

	{

	TMsvId entryId = aEntry->GetId();

	//	1. If the block is NULL, it creates a new one and appends the entry to the block

	//     and accordingly sets the TMsvId ranges.

	if(NULL == iBlockPtr)

		{

		iBlockPtr = new(ELeave) RPointerArray<CMsvCacheEntry>;

		iBlockPtr->AppendL(aEntry);

		SetMinMsvIdRange(entryId);

		SetMaxMsvIdRange(entryId);

		} //if(NULL == iBlockPtr)

	//	2. If block is not NULL:

	else

		{

		// 2.1 If the entry already exists in the block then release the old entry from the

		//	   block and append the new one.

		TInt blockSize = Size();

		for(TInt blockIndex = 0; blockIndex < blockSize; ++blockIndex)

			{

			if((*iBlockPtr)[blockIndex]->GetId() == aEntry->GetId())

				{

				if(!aReplace)

					{

					CMsvEntryFreePool::Instance()->ReleaseEntry(aEntry);

					aEntry = (*iBlockPtr)[blockIndex];

					return;

					}

				CMsvEntryFreePool::Instance()->ReleaseEntry((*iBlockPtr)[blockIndex]);

				iBlockPtr->Remove(blockIndex);

				iBlockPtr->Insert(aEntry, blockIndex);

				return;

				}

			}

		iBlockPtr->AppendL(aEntry);

		// 2.2 If the entry fits only at the end of the last block then we need to

		//     change the iMaxMsvid.

		//     If the indextable has not been created and if the folder has just

		//     one block, and this block contains random entries, then we may need to 

		//     set the iMinMsvId.

		if(entryId > iMaxMsvId)

			{

			SetMaxMsvIdRange(entryId);

			}

		if(entryId < iMinMsvId)

			{

			SetMinMsvIdRange(entryId);

			}

		} //else

	iTimeStamp.HomeTime();

	}

/**

 * AddEntrySetL()

 * @param RPointerArray<CMsvCacheEntry>& : reference to the new entry set to be added.

 * 										   These entries can either be immediate children

 * 										   or non-immediate children, but not both.

 * @param TInt aInitIndex : Start index of the entry to be added in the entryList.

 * @param TInt aCount     : Number of entries that should be added.

 * @return None.

 * 

 * The function adds a set of entries to the index table. The caller who passes the 

 * array of entries to the function will give up ownership of the entries in the array.

 * 1. When the block is NULL:

 * 	1.1 If children of a non-immediate folder are present in the array then set the 

 *      grandchildren and dirty flags.

 * 	1.2 If there aren't, then clear the above two flags.

 * 	1.3 Assign the new entry set to the block, but reset the passed set so that

 *	   the caller cannot modify or delete the cache entries.

 * 2. When the block is not NULL:

 *  2.1 If children of a non-immediate folder are present in the array then

 *	    set the grandchildren flag and simply append entries to the block.

 *  2.2 If there aren't, append entries avoiding duplication.

 * 		2.2.1 Search for each entry that is present in the current block in the

 *			  new set passed. If the entry is present then release it from the

 *			  current block. If not then append to the new set.

 * 		2.2.2 All entries are now in the passed array. Reset the current block,

 *			  allocate space for it and copy the entries to it. Also reset the 

 *			  passed array so that callers do not have access to the cache

 *			  entries after the addition.

 * 3. Calculate and set the maximum and minimum TMsvId ranges in the newly added set.

 */

void CMsvCacheIndexTableEntry::AddEntrySetL(RPointerArray<CMsvCacheEntry>& aEntries, TInt aInitIndex /*(DEFAULT=0)*/, TInt aCount /* DEFAULT=-1 */)

	{

	// Add all entries if aCount is -1.

	TInt arrSize = aEntries.Count();

	if(-1 == aCount)

		{

		aCount = arrSize;

		}

	if(aInitIndex < 0 || aInitIndex >= arrSize)

		{

		return;

		}

	// 1. When the block is NULL:

	if(NULL == iBlockPtr)

		{

		//     Assign the new entry set to the block, but reset the passed set so that

		//	   the caller cannot modify or delete the cache entries.

		//	   Update the ranges of the block.

		iBlockPtr = new(ELeave) RPointerArray<CMsvCacheEntry>;

		for(TInt listIndex = 0; (listIndex < aCount) && (arrSize > listIndex+aInitIndex); ++listIndex)

			{

			iBlockPtr->AppendL(aEntries[listIndex+aInitIndex]);

			}

		} //if(NULL == iBlockPtr)

	// 2. When the block is not NULL append the entries. If there is a duplicate entry,

	//	  discard the new entry.

	else

		{

		TBool entryFound = EFalse;

		TInt blockSize = Size();

		for(TInt listCount = 0; (listCount < aCount) && (arrSize > listCount+aInitIndex); ++listCount)

			{

			entryFound = EFalse;

			for(TInt blockIndex = 0; blockIndex < blockSize; ++blockIndex)

				{

				if(aEntries[listCount+aInitIndex]->GetId() == (*iBlockPtr)[blockIndex]->GetId())

					{

					CMsvEntryFreePool::Instance()->ReleaseEntry(aEntries[listCount+aInitIndex]);

					aEntries.Remove(listCount+aInitIndex);

					aEntries.Insert((*iBlockPtr)[blockIndex], listCount+aInitIndex);

					entryFound = ETrue;

					break;

					}

				}   //for()

			if(!entryFound)

				{

				iBlockPtr->AppendL(aEntries[listCount+aInitIndex]);

				}			

			}   //for()

		} //else

	iTimeStamp.HomeTime();

	}

/**

 * GetEntry()

 * @param TMsvId : the TMsvId of the entry to be fetched.

 * @param CMsvCacheEntry*& : output parameter for the entry.

 * @return TBool.

 * 

 * The function fetches the entry with the specified TMsvId.

 * 1. If the block is NULL, there is no entry that can be fetched. Return EFalse.

 * 2. Iterate through the block searching for the TMsvId and return ETrue for a hit

 * 3. Return EFalse if the entry is not present in the block.

 */

TBool CMsvCacheIndexTableEntry::GetEntry(TMsvId aId, CMsvCacheEntry*& aEntry)

	{

	// 1. If the block is NULL, there is no entry that can be fetched. Return EFalse.

	if(NULL == iBlockPtr)

		{

		aEntry = NULL;

		return EFalse;

		}

	//	2. Iterate through the block searching for the TMsvId and return ETrue for a hit.

	TInt blockSize = Size();

	for(TInt index = 0 ; index < blockSize ; ++index)

		{

		if((*iBlockPtr)[index]->GetId() ==  aId)

			{

			aEntry = (*iBlockPtr)[index];

			iTimeStamp.HomeTime();

			return ETrue;

			}

		} //for

	//	3. Return EFalse if the entry is not present in the block.

	return EFalse;

	}

/**

 * GetChildrenL()

 * @param TMsvId : TMsvId of the parent entry of the entries to be fetched.

 * @param RPointerArray<CMsvCacheEntry>*& : output parameter for the entries to be

 *        fetched.

 * @return None.

 * 

 * The function fetches a set of entries with the specified parent TMsvId.

 * 1. Check if there are grandchildren present in the block.

 * 	1.1. If yes, then fetch only those entries with parent Id as aParentId.

 * 		 If the array of entries is NULL, then allocate space for it.

 * 	1.2. If not, then return a copy of the whole block.

 */

void CMsvCacheIndexTableEntry::GetChildrenL(TMsvId aParentId, RPointerArray<CMsvCacheEntry>& aEntries) /*const*/

	{ 

	// 1. Check if there are grandchildren present in the block.

	if(IsGrandChildPresent())

		{

		// 1.1 If yes, then fetch only those entries with parent Id as aParentId.

		//       If the array of entries is NULL, then allocate space for it.

		TInt blockSize = Size();

		for(TInt index = 0 ; index < blockSize ; ++index)

			{

			if((*iBlockPtr)[index]->Entry().Parent() == aParentId)

				{

				aEntries.AppendL((*iBlockPtr)[index]);

				}

			}

		} //if(IsGrandChildPresent())

	else

		{

		// 1.2 If not, then return a copy of the whole block.

		TInt blockSize = Size();

		for(TInt index = 0 ; index < blockSize ; ++index)

			{

			aEntries.AppendL((*iBlockPtr)[index]);

			}

		} //else

	iTimeStamp.HomeTime();

	}

/**

 * DeleteEntryL()

 * @param TMsvId : the TMsvId of the entry to be deleted.

 * @param aParentIdOfEntry

 * @param aForceDelete TBool, it indicates whether the entry needs to be locked while deleting.

 * @return None.

 * 

 * The function deletes an entry from the cache releasing the entry to the cache free

 * pool. The function is called when the entry is being deleted from both the DB and

 * cache.

 * 1. Return if the block is NULL.

 * 2. Iterate through the block searching for the TMsvId.

 *	2.1 If the entry exists, remove it and release to the free pool. Deletion

 *		 is possible only if the entry is locked in the cache, otherwise the function

 * 		 returns KErrAccessDenied.

 * 		 2.1.1 If the entry deleted was the last entry in the block, delete the

 *		        block.

 * 3. Leave with KErrNotFound if the entry does not exist in the block.	

 */

void CMsvCacheIndexTableEntry::DeleteEntryL(TMsvId aId, TMsvId& aParentIdOfEntry /*DEFAULT = NULL*/, TBool aForceDelete /*DEFAULT=EFalse*/)

	{ 

	// 1. Return if the block is NULL.

	if(NULL == iBlockPtr)

		{

		User::Leave(KErrNotFound);

		}

	//	2. Iterate through the block searching for the TMsvId.

	TInt blockSize = Size();

	for(TInt index = 0 ; index < blockSize ; ++index)

		{

		//	2.1 If the entry exists, remove it and release to the free pool. Deletion

		//		 is possible only if the entry is locked in the cache.

		if((*iBlockPtr)[index]->GetId() ==  aId)

			{

			if(aForceDelete || (*iBlockPtr)[index]->IsEntryLocked())

				{

				aParentIdOfEntry = (*iBlockPtr)[index]->Entry().Parent();

				CMsvEntryFreePool::Instance()->ReleaseEntry((*iBlockPtr)[index]);

				iBlockPtr->Remove(index);

				// 2.1.1. If the entry deleted was the last entry in the block,

				//        delete the block.

				if(iBlockPtr->Count() == 0)

					{

					iBlockPtr->Close();

					delete iBlockPtr;

					iBlockPtr = NULL;

					}

				iTimeStamp.HomeTime();

				}

			else

				{

				User::Leave(KErrAccessDenied);

				}

			return;

			}

		} //for

	// 3. Leave with KErrNotFound if the entry does not exist in the block.

	User::Leave(KErrNotFound);

	}

/**

 * ReleaseBlock()

 * @param TBool: internally used flag which is used by destructor to forcibly swap out

 * 				 the block even if entries have been locked.

 * @return TBool: EFalse if block cannot be released as a result of entries having been

 * 				  locked in the cache, ETrue if otherwise.

 * 

 * The function releases a block to the cache free pool.

 * 1. Return EFalse if any of the entries in the block have been locked. Do not

 *    swap out the block to the free pool if so.

 * 2. No entries are locked and/or the block is to be swapped out forcibly.

 *  2.1 Release the entries to the free pool.

 *  2.2 Free the memory allocated to the block itself.

 *  2.3 Set the dirty flag.

 */

TBool CMsvCacheIndexTableEntry::ReleaseBlock(TBool aForceRelease /*DEFAULT = EFalse*/)

	{ 

	if(NULL == iBlockPtr)

		{

		return ETrue;

		}

	// 1. Return EFalse if any of the entries in the block have been locked. Do not

	//	  swap out the block to the free pool if so.

	if(!aForceRelease)

		{

		TInt blockSize = Size();

		for(TInt index = 0; index < blockSize; ++index)

			{

			if(!(*iBlockPtr)[index]->IsEntrySwappable())

				{

				return EFalse;

				}

			}

		}

	// 2. No entries are locked and the block can be swapped out safely.

	CMsvEntryFreePool::Instance()->ReleaseEntrySet(*iBlockPtr);

	iBlockPtr->Close();

	delete iBlockPtr;

	iBlockPtr = NULL;

	SetDirty();

	return ETrue;

	}

/**

 * CompareOrder()

 * @param const CMsvCacheEntry& : the first operand

 * @param const CMsvCacheEntry& : the second operand

 * @return TInt : the order (-1/0/+1)

 * 

 * The function returns the order for the sort operation.

 */

static TInt CompareOrder(const CMsvCacheEntry& aFirst, const CMsvCacheEntry& aSecond)

	{

	return aFirst.GetId() - aSecond.GetId();

	}

/**

 * SortBlockL()

 * @param None.

 * @return None.

 * 

 * The function is called by a background active object to sort the index table

 * according to TMsvIds of the entries.

 * 1. Sort based on the order in the TLinearOrder package.

 */