// 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 "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:

// mmcamerapolicymanager.cpp

// 

//

/**

 @file

 @internalComponent

*/

#include "mmcameraserversession.h"

#include "mmcameraserverpolicymanager.h"

#include "mmcameraservercontroller.h"

CMMCameraServerPolicyManager* CMMCameraServerPolicyManager::NewL()

	{

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

	CleanupStack::PushL(self);

	self->ConstructL();

	CleanupStack::Pop(self);

	return self;	

	}

CMMCameraServerPolicyManager::CMMCameraServerPolicyManager() : iReservedSessionQ(_FOFF(CMMCameraServerSession,iCamSessionLink)),

												iIter(iReservedSessionQ)

	{

	}

void CMMCameraServerPolicyManager::ConstructL()

	{

	}

CMMCameraServerPolicyManager::~CMMCameraServerPolicyManager()

	{	

	}

/**

 * Enforces client connection policies.

 * 

 * Called by the server as the client connects

 */

void CMMCameraServerPolicyManager::OnConnectL(const RMessage2& aMessage)

	{

	// All users must have UserEnvironment capability

	if (!KMMCameraServerPolicyUserEnvironment.CheckPolicy(aMessage, __PLATSEC_DIAGNOSTIC_STRING("CMMCameraServerPolicyManager::OnConnectL KMMCameraServerPolicyUserEnvironment")))

		{

		User::Leave(KErrPermissionDenied);

		}

	}

/**

 * Performs further MultimediaDD policy check on clients connecting to the server.

 * 

 * Called at the start of the Sessions ServiceL routine

 */

void CMMCameraServerPolicyManager::ServiceHandlerL(const RMessage2& aMessage)

	{

	// If client is connecting to the server, make sure correct capabilities are set

	if (aMessage.Function() == ECamOpenCamera)

		{

		// Insert MMCapability into message buffer

		TOpenCamera parameters;

		TOpenCameraPckg openCamBuf(parameters);

		aMessage.ReadL(TInt(0), openCamBuf);

		parameters = openCamBuf();

		if (KMMCameraServerPolicyMultimediaDD.CheckPolicy(aMessage, __PLATSEC_DIAGNOSTIC_STRING ("CMMCameraServerPolicyManager::ServiceHandlerL KMMCameraServerPolicyMultimediaDD")))

			{

			parameters.iMMCapability = ETrue;

			}

		else

			{

			parameters.iMMCapability = EFalse;

			}

	    TOpenCameraPckg buf(parameters);

	    aMessage.WriteL(TInt(0), buf);	

		}

	// Add code here if necessary to check

	// clients ability to access particular

	// functions

	}

/**

 * Used by ReserveClient() to find first reserved client session.

 */

CMMCameraServerSession* CMMCameraServerPolicyManager::FindFirstInQue(TInt aIndex)

	{

	CMMCameraServerSession* pS = NULL;

	iIter.SetToFirst();

	while ((pS = iIter++) != NULL)

		{

		if (pS->CameraIndex() == aIndex)

			{

			break;

			}

		}

	return pS;

	}

/**

 * Used by CheckControlOvertaking() to find last client in queue that has reserved the camera.

 */

CMMCameraServerSession* CMMCameraServerPolicyManager::FindLastInQue(TInt aIndex)

	{

	CMMCameraServerSession *pS, *ret = NULL;

	iIter.SetToFirst();

	while ((pS = iIter++) != NULL)

		{

		if (pS->CameraIndex() == aIndex)

			{

			ret = pS;

			}

		}

	return ret;

	}

/**

 * Attempts to reserve the specific camera which the client requested.

 */

TBool CMMCameraServerPolicyManager::ReserveClient(CMMCameraServerSession* aSession)

	{

	TInt camIndex = aSession->CameraIndex();

	// Check if this is the first client reserving the camera device

	if (FindFirstInQue(camIndex) == NULL)

		{

		ReserveUpdate(aSession);

		return ETrue;

		}

	else 

		{

		// If not first client, check if it is a collaborative client with the one which has already reseved the camera

		if(aSession->CollaborativeClient())

			{

			// Get the First session in the queue

			// All collaborative clients require the same MMCapability

			CMMCameraServerSession* firstSession = FindFirstInQue(camIndex);

			if (aSession->MMCapability() == firstSession->MMCapability())

				{

				// Set the priority of the collaborative client to that of the first client

				aSession->SetPriority(firstSession->Priority());

				iReservedSessionQ.AddLast(*aSession);

				return ETrue;

				}

			}

		// See if new client has higher priority than current client

		if(CheckControlOvertaking(aSession)) 

			{

			CMMCameraServerSession* pS = NULL;

			iIter.SetToFirst();

			aSession->CameraController()->Reset();

			while ((pS = iIter++) != NULL)

				{

				// We Deque and overthrow those clients that 

				// belong to the same camIndex as this client

				if (pS->CameraIndex() == camIndex)

					{

					// set reserve status of previously reserved client to EFalse. 

					pS->SetReserved(EFalse);

					pS->CompleteOverthrow();

					//removes from controller's 'reserved session' queue

					pS->iCamSessionLink.Deque();

					pS->iCamSessionLink.iNext = NULL;

					}

				}

			// update details wrt new reserved client. 

			ReserveUpdate(aSession);

			return ETrue;

			}

		}

	return EFalse;

	}

/**

 * Updates reserve status of clients. Used by ReserveClient().

 */

void CMMCameraServerPolicyManager::ReserveUpdate(CMMCameraServerSession* aSession)

	{

	aSession->SetHandle(aSession->CameraController()->CameraHandle());

	iReservedSessionQ.AddLast(*aSession);

	}

/**

 * Determines whether overthrowing client has higher priority than current client.

 * Used by ReserveClient().

 */

TBool CMMCameraServerPolicyManager::CheckControlOvertaking(CMMCameraServerSession* aSession)

	{

	TInt camIndex = aSession->CameraIndex();

	CMMCameraServerSession* lastSession = FindLastInQue(camIndex);

	if(aSession->MMCapability() && !(lastSession->MMCapability()))  

		{

		return ETrue;

		}

	if(aSession->MMCapability() == lastSession->MMCapability())

		{

		if(aSession->Priority() > lastSession->Priority())

			{

			return ETrue;

			}

		}

	return EFalse;

	}

/**

 * Releases the camera device.

 */

void CMMCameraServerPolicyManager::ReleaseClient(CMMCameraServerSession* aSession)

	{

	if(!iReservedSessionQ.IsEmpty())

		{

		aSession->iCamSessionLink.Deque();

		aSession->iCamSessionLink.iNext = NULL;

		}

	}