/*

* Copyright (c) 2004-2007 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:  An interface for contact views.

*

*/

#ifndef MVPBKCONTACTVIEWBASE_H

#define MVPBKCONTACTVIEWBASE_H

// INCLUDES

#include <e32cmn.h>

#include <vpbkcontactview.hrh>

#include <bamdesca.h>

// FORWARD DECLARATIONS

class MVPbkContactViewObserver;

class MVPbkViewContact;

class MVPbkContactLink;

class MVPbkFieldTypeList;

class MVPbkContactBookmark;

class MVPbkContactViewFiltering;

// CLASS DECLARATIONS

/**

 * An common interface for different contact views.

 * 

 * The contact view interface has many implementations. It can be a view from

 * a single contact store or it can be a composite of contact/group views from

 * different stores. It's also possible that it contains folding items that

 * are not from any store. The client defines the view structure.

 * 

 * The most common usage is that client uses CVPbkContactManager 

 * for creating a contact view and defines the structure of the view.

 * @see CVPbkContactManager::CreateContactViewLC

 */

class MVPbkContactViewBase

    {

    public:  // Destructor

        /**

         * Destructor.

         */

        virtual ~MVPbkContactViewBase() { }

    public:  // New functions

        /**

         * Returns type of this contact view.

         *

         * @return A contact view type.

         */

        virtual TVPbkContactViewType Type() const = 0;

        /**

         * Changes sort order of the view asynchronously.

         *

         * Clients of this view will get an event via MVPbkContactViewObserver

         * interface when the order has been updated. The leaf view sends

         * a pair of events. First it sends ContactViewUnavailable and then

         * after the order has been changed ContactViewReady. However if

         * the view is of type EVPbkCompositeView the client doesn't necessary

         * receive ContactViewUnavailable at all because it might be that

         * there is always some subview ready in the composite.

         *

         * @param aSortOrder A new sort order for this view.

         * @exception KErrArgument Possible reasons: a client tries to change

         *                         a sort order of platform defined shared

         *                         view against the platform setting.

         * @see CVPbkSortOrder

         */

        virtual void ChangeSortOrderL(

                const MVPbkFieldTypeList& aSortOrder ) = 0;

        /**

         * Returns the current sort order of the view.

         *

         * The sort order is a sub set of master field types from

         * CVPbkContactManager.

         *

         * @return The sort order of the view.

         */

        virtual const MVPbkFieldTypeList& SortOrder() const = 0;

        /**

         * Refreshes the view contents asynchronously.

         * 

         * All handles to this view's contacts are invalidated.

         * Clients of this view will get an event via MVPbkContactViewObserver

         * interface when the view has been refreshed.

         */

        virtual void RefreshL() = 0;

        /**

         * Returns the number of contacts in this view.

         *

         * @return The number of contacts.

         */

        virtual TInt ContactCountL() const = 0;

        /**

         * Returns a contact in this view. 

         *

         * The returned reference may be invalidated when this 

         * function is called again. For that reason clients should prefer

         * not to save references to the contacts retrieved from this function.

         *

         * @param aIndex An index of the contact in this view.

         * @return A reference to a contact in this view at aIndex.

         * @precond aIndex >= 0

         *              VPbkError::Panic(VPbkError::EInvalidContactIndex)

         *              is raised if the precondition does not hold.

         * @exception KErrArgument if aIndex >= ContactCountL()

         */

        virtual const MVPbkViewContact& ContactAtL(

                TInt aIndex ) const = 0;

        /**

         * Creates and returns a link that points to contact at aIndex.

         *

         * NOTE: If the view contact is not from any store it can return

         *       also NULL. E.g. if the view contact is a folding 

         *       contact view that it's not saved to any store.

         *       The NULL is not pushed onto the cleanup stack.

         *

         * @param aIndex An index of the contact for which the link

         *               is created.

         * @return A new link object pointing to contact at aIndex or NULL if

         *          the link can't be created (e.g. a folder).

         * @precond aIndex >= 0

         *          VPbkError::Panic(VPbkError::EInvalidContactIndex)

         *          is raised if the precondition does not hold.

         * @exception KErrArgument if aIndex >= ContactCountL()

         */

        virtual MVPbkContactLink* CreateLinkLC(

                TInt aIndex ) const = 0;

        /**

         * Returns The index of the aContactLink in this view.

         *

         * If the identifier is not found from the view then

         * KErrNotFound is returned. If the view is not from

         * any store (e.g. a folding view) then it will also

         * return KErrNotFound.

         *

         * NOTE: the implementation of this function probably

         *       must loop the view which means that calling

         *       this function frequently or in a loop can

         *       be slow when there are lots of contacts.

         *

         * @param aContactLink A link whose index is searched for.

         * @return The index of the link or KErrNotFound.

         */

        virtual TInt IndexOfLinkL(

                const MVPbkContactLink& aContactLink ) const = 0;

        /**

         * Adds an observer to this contact view asynchronously. 

         *

         * The observer will be notified after it has been added

         * to the view.

         *

         * @param aObserver A new observer for the view.

         */

        virtual void AddObserverL(

                MVPbkContactViewObserver& aObserver ) = 0;

        /**

         * Removes an observer from this contact view.

         *

         * This method can be called even if aObserver has not been

         * previously added. In that case, no observers are removed.

         *

         * @param aObserver The observer to be removed.

         */

        virtual void RemoveObserver(

                MVPbkContactViewObserver& aObserver ) = 0;

        /**

         * Returns ETrue if this view is from a store identified 

         * by aContactStoreUri.

         *

         * @param aContactStoreUri The whole URI of the contact store.

         * @return ETrue if the view was from the given store.

         *

         * @see TVPbkContactStoreUriPtr::UriDes

         */

        virtual TBool MatchContactStore(

                const TDesC& aContactStoreUri ) const = 0;

        /**

         * Returns ETrue if this view is from a store domain identified 

         * by aContactStoreDomain.

         *

         * @param aContactStoreDomain The domain part of the contact store URI.

         *                            The domain can be retrieved from the 

         *                            whole contact store URI using class 

         *                            TVPbkContactStoreUriPtr and 

         *                            EContactStoreUriStoreType.

         *                            An implementation compares the

         *                            EContactStoreUriStoreType part of 

         *                            its own URI to aContactStoreDomain.

         *                            

         * @return ETrue if the view was from the same store domain.

         * @see TVPbkContactStoreUriPtr

         */

        virtual TBool MatchContactStoreDomain(

                const TDesC& aContactStoreDomain ) const = 0;

        /**

         * Creates and returns a bookmark that points to the

         * view contact at aIndex.

         *

         * @param aIndex An index of the contact in the view.

         * @return A new bookmark to the view item.

         * @precond aIndex >= 0

         *          VPbkError::Panic(VPbkError::EInvalidContactIndex)

         *          is raised if the precondition does not hold.

         */

        virtual MVPbkContactBookmark* CreateBookmarkLC(

                TInt aIndex ) const = 0;

        /**

         * Returns an index of the contact in the view.

         *

         * If the identifier is not found from the view then

         * KErrNotFound is returned.

         *

         * NOTE: the implementation of this function probably

         *       must loop the view which means that calling

         *       this function frequently or in a loop can

         *       be slow when there are lots of contacts.

         *

         * @param aContactBookmark A bookmark that identifies

         *                         a contact in the view.

         * @return An index of the contact in the view or KErrNotFound.

         */

        virtual TInt IndexOfBookmarkL(

                const MVPbkContactBookmark& aContactBookmark ) const = 0;

        /**

         * Returns an interface for text based contact filtering support.

         *

         * If the view doesn't support filtering then this returns NULL. 

         * Filtering must be supported in all views created from a contact

         * store. However, it's possible to implement a view that doesn't

         * need a filtering support and therefore clients must always check

         * the returned pointer.

         *

         * @return A filtering interface or NULL

         */

        virtual MVPbkContactViewFiltering* ViewFiltering() = 0;

        /**

         * Returns an extension point for this interface or NULL.

         *

         * @param aExtensionUid no extensions defined currently.

         * @return an extension point for this interface or NULL.

         */

        virtual TAny* ContactViewBaseExtension(TUid /*aExtensionUid*/) 

                { return NULL; }

    };

#endif // MVPBKCONTACTVIEWBASE_H

// End of File