diff -r 000000000000 -r c53acadfccc6 contextengine/inc/contextengineao.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/contextengine/inc/contextengineao.h	Mon Jan 18 20:34:07 2010 +0200
@@ -0,0 +1,247 @@
+/*
+* 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:
+*
+*/
+
+
+#ifndef CONTEXTENGINEAO_H
+#define CONTEXTENGINEAO_H
+
+// system include
+#include <e32base.h>
+
+// user include
+#include "contextplugin.h"
+#include "mpropertyobserver.h"
+
+// forward declarations
+class CContextSnapshotItem;
+class MContextInitializationObserver;
+class MContextSnapshotObserver;
+class CMdESession;
+class CPropertyWatcher;
+
+/**
+* This class implements an active object for collecting context metadata
+* asyncronously from the context plugins.
+*/
+NONSHARABLE_CLASS( CContextEngineAO ) : public CActive, 
+									    public MContextPluginObserver,
+										public MKeyObserver
+  	{
+public:
+
+	/**
+	 * State for context engine (=this active object).
+	 * Possible states: Ready for snapshot, initializing plugins or taking a snapshot.
+	 */
+	enum TContextEngineState { EReady = 0, EInitialization, ESnapshot };
+
+	/**
+	 * Creates and constructs a new instance of CContextEngineAO.
+	 *
+	 * @return A pointer to the new instance.
+	 */
+	static CContextEngineAO* NewL( MContextInitializationObserver* aInitObserver,
+		MContextSnapshotObserver* aSnapshotObserver );
+
+	/**
+	 * Destructor.
+	 */
+	virtual ~CContextEngineAO();
+
+public:
+	/**
+	 * Set a pointer to MdESession. The pointer is given forward to context plugins.
+	 * Session must be set in order to successfully harvest context data.
+	 *
+	 * @param aSession Session pointer to set.
+	 */
+	void SetMdeSession( CMdESession* aSession );
+
+	/**
+	 * Start taking a context snapshot (for multiple objects).
+	 *
+	 * @param aItem  Observer to inform about snapshot completion
+	 *               and MdE objects the snapshot is taken to.
+	 */
+	void StartSnapshot( CContextSnapshotItem* aItem );
+
+	/**
+	 * Method used to clarify how many plug-ins are loaded.
+	 *
+	 * @return Amount of plug-ins loaded.
+	 */
+	TInt PluginCount();
+
+public:   // from base class CActive
+
+	/**
+	 * From CActive.
+	 * Every call takes a context snapshot from one plug-in.
+	 */
+	void RunL();
+
+	/**
+	 * From CActive.
+	 * Handles a leave occurring in the request completion event handler RunL().
+	 *
+	 * @param aError  An error code.
+	 * @return An error code.
+	 */
+	TInt RunError( TInt aError );
+
+	/**
+	 * From CActive.
+	 * Cancels ????.
+	 */
+	void DoCancel();
+
+public:   // from MContextPluginObserver
+
+	/**
+	 * From MContextPluginObserver.
+	 * This is derived from MContextPluginObserver and it is called
+	 * by each plug-in when they have initialized.
+	 * Error code for the first encountered error is returned as a parameter.
+	 *
+	 * @param aErrorCode  Error code for the first error occurred during initialization.
+	 */
+	void PluginInitializationStatus( TInt aErrorCode );
+	
+	/**
+	 * From MContextPluginObserver.
+	 * This is derived from MContextPluginObserver and it is called
+	 * by each plug-in when they have taken the context snapshot.
+	 * Error code for the first encountered error is returned as a parameter.
+	 *
+	 * @param aErrorCode  Error code for the first error occurred while taking the snapshot.
+	 */
+	void PluginSnapshotStatus( CHarvesterData* aHD );
+        
+public: // From MKeyObserver.   	
+
+	/**
+	 * Method NotifyKeyL from MKeyObserver get notifications when
+	 * property key has changed.
+	 */
+	void NotifyKeyL( 
+			const TInt aKeyValue,
+			const TUid aPropertyCategory,
+			const TUint aKey );     
+
+private:
+
+	/**
+	 * Default constructor, implicitly called by NewL().
+	 */
+	CContextEngineAO( MContextInitializationObserver* aInitObserver,
+		MContextSnapshotObserver* aSnapshotObserver );
+
+	/**
+	 * 2nd phase construction, called by NewL().
+	 */
+	void ConstructL();
+
+	/**
+	 * Load context plugins.
+	 */
+	void LoadPluginsL();
+
+	/**
+	 * Initialize this object. Thus load and initialize context plugins.
+	 */
+	void InitializeL();
+
+	/**
+	  * Called when
+	  * Backup&Restore is backing up or restoring.
+	  */
+	 void BackupRestoreStart();
+
+	 /**
+	  * Called when
+	  * Backup&Restore has finished backup or restore.
+	  */
+	 void BackupRestoreReady();
+
+	/**
+	 * Method HandleBackupRestoreKeyActionL.
+	 * If user make full restore sets restore flag on.
+	 */
+	void HandleBackupRestoreKeyAction( const TUint aKeyValue );
+    
+private: // data
+
+	/**
+	 * This observer is used to inform the client application about
+	 * finishing plug-in initializations.
+	 */
+	MContextInitializationObserver* iInitializationObserver;
+	
+	/**
+	 * This observer is used to inform Context Engine about
+	 * finishing a context snapshot.
+	 */
+	MContextSnapshotObserver* iContextSnapshotObserver;
+
+	/**
+	 * Plug-in array contains the plug-ins.
+	 */
+	RPointerArray<CContextPlugin> iPlugins;
+
+	/**
+	 * Number of plug-ins currently not being initialized yet.
+	 */
+	TInt iUninitializedPluginsCount;
+	
+	/**
+	 * Number of HDs currently not completed the snapshot yet.
+	 */
+	TInt iPluginSnapshotsLacking;
+	
+	/**
+	 * Item to which we are currently doing a snapshot for.
+	 */
+	CContextSnapshotItem* iItem;
+	
+	/**
+	 * State of this active object.
+	 */
+	TContextEngineState iState;
+	
+	/** First error code encountered in initialization is cached here and returned later. */
+	TInt iInitializationError;
+	
+	/** First error code encountered in snapshot is cached here and returned later. */
+	TInt iSnapshotError;
+	
+	/**
+	  * iMdESession - MDE session.
+	  */
+	CMdESession* iMdESession;
+
+	/**
+	 * iPropertyWatcher - constains observed key's, owned by this class.
+	 */
+	CPropertyWatcher* iPropertyWatcher;
+	
+    /**
+     * iPropertyWatcher - used to check if only one plugin has not finished work.
+     */
+    TBool iLastPlugin;
+    };
+
+#endif // CONTEXTENGINEAO_H