/*

* 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:    List of media items

*

*/

#ifndef C_GLXMEDIALIST_H

#define C_GLXMEDIALIST_H

#include <e32std.h>

#include <mpxattributespecs.h>

#include <mpxcollectionobserver.h>

#include "mglxmedialist.h"

#include "mglxnavigablelistobserver.h"

#include "mglxmediauser.h"

// Forward declarations

class CGlxCacheManager;

class CGlxErrorPoster;

class CGlxNavigableList;

class CMPXCollectionPath;

class MGlxFetchContext;

class MMPXCollection;

class MMPXCollectionUtility;

class TGlxMedia;

class CGlxMediaListArray;

namespace NGlxMediaList

    {

    class TNotificationStrategy;

    }

/**

 * CGlxMediaList

 *

 * Interface for reading lists of media items

 *

 * @ingroup mlm_media_list_manager_design

 * @lib glxmedialists.lib

 */

class CGlxMediaList :

    public CBase, public MGlxMediaList, public MMPXCollectionObserver, 

        public MGlxNavigableListObserver, public MGlxMediaUser    

    {

public:

    /**

     * Return a reference-counted instance of CGlxMediaList. User MUST Close() this when finished with it.

     *

     * @param aPath Path to the collection

     * @param aHierarchyId Id of the client hierarchy

     * @param aFilter Filter on the collection

     * @return instance of media list object

     */

    static CGlxMediaList* InstanceL(const CMPXCollectionPath& aPath, 

        const TGlxHierarchyId& aHierarchyId = KGlxIdNone, CMPXFilter* aFilter = NULL);

    /**

     * Gives an array of all media lists in current use

     *

     * @return The array of media lists

     */

    static RPointerArray<CGlxMediaList>& MediaListsL();

public:

    /**

     * Media object is available. The list picks up the pointer to the media object 

     * if it has a matching item, and adds itself as a user of the media object

     * The index into the list is also stored, to allow clients that

     * are processing users of a media, to index directly into the list

     * Note: The function assumes that a reservation for at least one list has been

     * made in each CGlxMedia::iUsedByLists array, and this object can use that 

     * reservation

     *

     * @param aItems media items to offer to list

     */

    void OfferMedia(const TGlxIdSpaceId& aIdSpaceId, CGlxMedia* aItems);

    /**

     * Ask if the list has any requests to place

     *

     * @param aItemIndexes Indexes of the items to request attributes for

     * @param aItemIds Ids of the items to request attributes for

     * @param aAttributes attributes to request for the items

     * @param aDetailedSpecs attribute specifications

     */

    /**

     * Ordering function for attributes

     *

     * @see TLinearOrder

     *

     * @param aItem1 first item to order

     * @param aItem2 second item to order

     * @return TInt indicating ordering

     */

    static TInt AttributeOrder(const TMPXAttribute& aItem1, const TMPXAttribute& aItem2);

    /**

     * Ordering function for attributes

     *

     * @see TLinearOrder

     *

     * @param aItem1 first item to order

     * @param aItem2 second item to order

     * @return TInt indicating ordering

     */

    static TInt AttributeOrderReversed(const TMPXAttribute& aItem1, const TMPXAttribute& aItem2);

public: // From MGlxMediaList

    /// See @ref MGlxMediaList::Close

    void Close();

    /// See @ref MGlxMediaList::Id

    TGlxMediaListId Id() const;

    /// See @ref MGlxMediaList::Count

    TInt Count(NGlxListDefs::TCountType aType = NGlxListDefs::ECountAll) const;

    /// See @ref MGlxMediaList::FocusIndex

    TInt FocusIndex() const;

    /// See @ref MGlxMediaList::SetFocusL

    void SetFocusL(NGlxListDefs::TFocusSetType aType, TInt aValue);

    /// See @ref MGlxMediaList::Item

    const TGlxMedia& Item(TInt aIndex) const;

    /// See @ref MGlxMediaList::Index

    TInt Index(const TGlxIdSpaceId& aIdSpaceId, const TGlxMediaId& aId) const;

    /// See @ref MGlxMediaList::AddMediaListObserverL

    void AddMediaListObserverL(MGlxMediaListObserver* aObserver);

    /// See @ref MGlxMediaList::RemoveMediaListObserver

    void RemoveMediaListObserver(MGlxMediaListObserver* aObserver);

    /// See @ref MGlxMediaList::AddContext

    void AddContextL(const MGlxFetchContext* aContext, TInt aPriority);

    /// See @ref MGlxMediaList::RemoveContext

    void RemoveContext(const MGlxFetchContext* aContext);

    /// See @ref MGlxMediaList::Collection

    MMPXCollection& Collection() const;

    /// See @ref MGlxMediaList::PathLC

    CMPXCollectionPath* PathLC(NGlxListDefs::TPathType aType = NGlxListDefs::EPathAllOrSelection) const;

    /// See @ref MGlxMediaList::IsSelected

    TBool IsSelected(TInt aIndex) const;

    /// See @ref MGlxMediaList::SetSelectedL

    void SetSelectedL(TInt aIndex, TBool aSelected);

    /// See @ref MGlxMediaList::SelectionCount

    TInt SelectionCount() const;

    /// See @ref MGlxMediaList::SelectedItemIndex

    TInt SelectedItemIndex(TInt aSelectionIndex) const;

    /// See @ref MGlxMediaList::CommandL

    void CommandL(CMPXCommand& aCommand);

    /// See @ref MGlxMediaList::CancelCommand

    void CancelCommand();

    /// See @ref MGlxMediaList::IsCommandActive

    TBool IsCommandActive();

    /// See @ref MGlxMediaList::SetFilterL

    void SetFilterL(CMPXFilter* aFilter);

    /// See @ref MGlxMediaList::Filter

    CMPXFilter* Filter() const;

    /// See @ref MGlxMediaList::IdSpaceId

    TGlxIdSpaceId IdSpaceId(TInt aIndex) const;

    /// See @ref MGlxMediaList::IsPopulated

    TBool IsPopulated() const;

    /// See @ref MGlxMediaList::AddStaticItemL

    void AddStaticItemL( CGlxMedia* aStaticItem,

        NGlxListDefs::TInsertionPosition aTargetPosition );

    /// See @ref MGlxMediaList::RemoveStaticItem

      void RemoveStaticItem(const TGlxMediaId& aItemId);

    /// See @ref MGlxMediaList::SetStaticItemsEnabled

    void SetStaticItemsEnabled( TBool aEnabled );

    /// See @ref MGlxMediaList::IsStaticItemsEnabled

    TBool IsStaticItemsEnabled() const;

    /// See @ref MGlxMediaList::SetFocusInitialPosition

    void SetFocusInitialPosition(NGlxListDefs::TFocusInitialPosition aFocusInitialPosition);

    /// See @ref MGlxMediaList::ResetFocus

    void ResetFocus();

    /// See @ref MGlxMediaList::SetVisibleWindowIndex  

    void SetVisibleWindowIndexL( TInt aIndex );

    /// See @ref MGlxMediaList::VisibleWindowIndex

    TInt VisibleWindowIndex() const;

	/// See @ref MGlxMediaList::CancelPreviousRequests

    void  CancelPreviousRequests();

public: // From MMPXCollectionObserver

    /// See @ref MMPXCollectionObserver::HandleCollectionMessageL

    void HandleCollectionMessageL(const CMPXMessage& aMessage);

    /// See @ref MMPXCollectionObserver::HandleOpenL

    void HandleOpenL(const CMPXMedia& aEntries, TInt aIndex, TBool aComplete, TInt aError);

    /// See @ref MMPXCollectionObserver::HandleOpenL

    void HandleOpenL(const CMPXCollectionPlaylist& aPlaylist, TInt aError);  

    /// See @ref MMPXCollectionObserver::HandleCollectionMediaL

    void HandleCollectionMediaL(const CMPXMedia& aMedia, TInt aError);

    /// See @ref MMPXCollectionObserver::HandleCommandComplete

    void HandleCommandComplete(CMPXCommand* aCommandResult, TInt aError);

    // from MGlxNavigableListObserver

    void HandleItemsAdded( TInt aAddedAtIndex, TInt aCount );

    void HandleItemsRemoved( TInt aRemovedFromIndex, TInt aCount );

    void HandleFocusChanged( NGlxListDefs::TFocusChangeType aType, 

        TInt aNewIndex, TInt aOldIndex );

    void HandleItemSelected( TInt aIndex, TBool aSelected );

    // From MGlxMediaUser

    void HandleAttributesAvailableL( TInt aIndex, const RArray< TMPXAttribute >& aAttributes );

    void GetRequiredAttributesL( TInt aIndex, RArray<TMPXAttribute>& aAttributes );

    void RemoveReference( TInt aIndex );

    void HandleError(TInt aError);

private:

    /**

     * Two phase constructor

     */

    static CGlxMediaList* NewLC(const TGlxHierarchyId& aHierarchyId);

    /**

     * Constructor

     */

    CGlxMediaList(const TGlxHierarchyId& aHierarchyId);

    /**

     * Destructor

     */

    virtual ~CGlxMediaList();

    /**

     * 2nd phase constructor

     */

    void ConstructL();

    /**

     * Initialize the media list

     * Copies the levels from the path, and retrieves the 

     * contents from MPX Collection Server

     *

     * @param aPath path that this list refers to

     */

    void OpenL(const CMPXCollectionPath& aPath);

    /**

     * Add a reference

     *

     * @return new reference count

     */

    TInt AddReference();

    /**

     * Remove a reference

     *

     * @return new reference count

     */

    TInt RemoveReference();

    /**

     * Current number of references

     *

     * @return new reference count

     */

    TInt ReferenceCount() const;

    /**

     * Determines if path is the same

     *

     * @param aPath collection path

     * @return ETrue if this media list refers to the path

     */

    TBool Equals(const CMPXCollectionPath& aPath) const;

    /**

     * Determines if this list has a filter applied

     *

     * @return Boolean indication if filter has been applied

     */

    TBool IsFiltered() const;

    /**

     * Synchronise the media list

     * Re-retrieves the contents from MPX Collection Server

     */

    void ReOpenL();

    /**

     * Populates the list with the items in the current path

     */

    void PopulateL();

    /**

     * Handles item modifications

     *

     * @param aId MPX item id

     * @param aAttributes Attributes that have been modified

     */

    void HandleItemModifiedL(TInt aId, const RArray<TMPXAttribute>& aAttributes);

    /**

     * Notify observers of media object being now available

     *

     * @param aListIndex index of item for which properties are available

     */

    void NotifyObserversOfMediaL(TInt aListIndex);

    /**

     * Notify observers, and reports errors to error manager

     */

    void NotifyObservers( NGlxMediaList::TNotificationStrategy& aStrategy );

    /**

     * Populates the path with hierarchy to parent

     *

     * @param aPath path to populate

     */

    void PathPopulateParentL(CMPXCollectionPath& aPath) const;

    /**

     * Populates the path with all items

     * and sets the focus

     *

     * @param aPath path to populate

     */

    void PathPopulateAllL(CMPXCollectionPath& aPath) const;

    /**

     * Populates the path with focused item

     * and sets the focus

     *

     * @param aPath path to populate

     */

    void PathPopulateFocusL(CMPXCollectionPath& aPath) const;

    /**

     * Populates the path with selected items

     * and selects all

     *

     * @param aPath path to populate

     */

    void PathPopulateSelectionL(CMPXCollectionPath& aPath) const;

    /*

     * Updates each media used by this media list with the current index

     */

    void UpdateMedia();

    /*

     * Updates each media used by this media list with the current index

     */

    void UpdateMediaInvalidateAttributesChangedByCounts(TGlxMedia& aItem);

    /**

     * Opens a collection at the appropriate level

     *

     * @param aPath used to determine which collection and level to open

     */

    void OpenCollectionL(const CMPXCollectionPath& aPath);

    /**

     * Handles the tasks after open completes

     */

    void HandleOpenL();

private:

    /** 

     * Enumeration to indicate pending sync status

     */ 

    enum TSyncStatus

        {

        KNonePending,

        KSyncPending,

        KResyncPending

        };

    /** 

     * TContext

     */ 

    struct TContext

        {

        /**

         * Find match by context pointer

         */

        static TBool Match(const TContext& a1, const TContext& a2);

        /**

         * Compare by comparing priority

         */

        static TInt Compare(const TContext& a1, const TContext& a2);

        const MGlxFetchContext* iContext; // Not owned

        TInt iPriority; // Priority, higher is more important

        };

private:

    /**

     * Number of users of this object

     */

    TInt iReferenceCount;

    /**

     * Manager of this list

     * Not owned

     */

    CGlxCacheManager* iManager;

    /**

     * Observers that will be notified if items get added or removed or if they change

     * Not owned

     */

    RPointerArray<MGlxMediaListObserver> iItemListObservers; 

    /**

     * Contexts that contain intelligence of attribute (e.g.,

     * thumbnail of URI) retrieving, incl. priorities.  Not owned

     */

    RArray<TContext> iContexts;

    /** List that contains items, focus, and selection */

    CGlxNavigableList* iItemList;

    /**

     * Collection utility that is bound to this list. 

     */

    MMPXCollectionUtility* iCollectionUtility; // own

    RArray<TGlxMediaId> iPath;

    /**

     * Indicates if a command has already been placed on the collection, which has not complete yet.

     * Currently, only one command can be made at a time

     * Stores the sessionId (client that issued the command)

     */

    TAny* iCommandPending;

    /**

     * Filter currently set on the collection.  Owned

     */

    CMPXFilter* iFilter;

    /// IdSpaceId for items in the list.

    TGlxIdSpaceId iIdSpaceId;

    TGlxHierarchyId iHierarchyId;

    /**

     * Is populated, set to ETrue

     * when the media list is first populated.

     */

    TBool iIsPopulated;

    /**

     * Singleton to post errors to

     */

    CGlxErrorPoster* iErrorPoster;

    /// Indicates that filter was set, so need to re-order contents

    TBool iReorderPending;

    /// Indicates that item(s) updated, so need to sync now or resync later

    TSyncStatus iSyncStatus;

    /**

     * Array of media lists

     * (singleton: should be closed, not deleted)

     */

    CGlxMediaListArray* iMediaListArray;

    /// Array of attributes to be invalidated when items are added or removed

    RArray<TMPXAttribute> iCountAttributes;

    /// VisibleWindow Index 

    TInt iVisibleWindowIndex;

    };

#endif // C_GLXMEDIALIST_H