/*

* Copyright (c) 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:  Visual template class for alfred widget model.

*      This class creates and updates visual tree.

*

*/

#ifndef I_ALFVISUALTEMPLATE_H

#define I_ALFVISUALTEMPLATE_H

#include <alf/ialfinterfacebase.h>

#include <alf/alftypes.h>

#include <osn/ustring.h>

#include <alf/alflayout.h>

class CAlfVisual;

class CAlfControl;

class CAlfBrush;

class CAlfLayout;

namespace duiuimodel

    {

    //FORWARD DECLARATIONS

    class DuiNode;	

    }	

using namespace duiuimodel;

using namespace osncore;

namespace Alf

    {

// FORWARD DECLARATIONS

class IAlfMap;

class IAlfAttributeSetter;

class IAlfElement;

class AlfAttributeContainer;

class AlfCustomInitDataBase;  

namespace alfvisualtemplate

    {

static const IfId ident =

    {

    0, "alfvisualtemplate"

    };

    }

//INTERFACE DECLARATIONS

/**

 * An interface for visual templates.

 *

 * A visual template hierarchy can be formed using visual template objects. From a visual template

 * hierarchy a concrete visual tree can be constructed that composes of toolkit visuals.

 * Produced concrete visual tree will match the visual template hierarchy constructed by

 * adding visual templates as children of each other. User can create any number of identical 

 * visual trees from one visual template hierarchy. Each visual template object creates 

 * one visual in the produced concrete visual tree.

 *

 * A visual template can be owned by a widget element (Alf::IAlfElement).

 * Only root visual templates of a visual template hierarchy can be owned by an element.

 * As a consequence of this an owner element of a visual template and a parent visual template

 * are mutually exclusive properties. That is, if a visual template is a child of

 * another visual template it cannot be owned by an element. Also if an element

 * owns a visual template it cannot be a child of another visual template.

 *

 * If a child visual template is set to an element the connection between child visual template

 * and its parent is removed thus making the visual template a root of the visual template hierarchy

 * below it. Similarly if a visual template owned by an element is set as a child to a visual template

 * the ownership of that visual template by its element is removed leaving the element with no visual

 * template. 

 *

 * Concrete visual trees can be produced using createVisualTree() method. Existing concrete visual

 * trees can be updated using the updateVisualTree() method. Attributes of the produced concrete 

 * visuals can be manipulated through attribute setters and containers assigned to visual template

 * using method addAttributeSetter(). Data that is passed to the createVisualTree() and updateVisualTree()

 * methods contain the attribute values that are set to the concrete visuals giving users a 

 * possibility to customize the produced concrete visual trees.

 *

 * @see Alf::IAlfElement

 *

 * @lib alfwidgetmodel.lib

 * @since S60 ?S60_version

 * @status Draft

 */

class IAlfVisualTemplate : public IAlfInterfaceBase

    {

public:

    /**

     * Getter for the type identifier of this interface.

     *

     * @since S60 ?S60_version

     * @return Identifier of this interface.

     */

    static inline const IfId& type()

        {

        return alfvisualtemplate::ident;

        }

    /** Virtual destructor. */

    virtual ~IAlfVisualTemplate() {}

    /**

     * Sets the owner element. User should not call this method directly. It will

     * be called implicitly by Alf::IAlfElement::setVisualTemplate() method.

     * Call to this method cannot throw an exception.

     *

     * @see Alf::IAlfElement::setVisualTemplate()

     *

     * @since S60 ?S60_version

     *

     * @param aOwner Element that owns this root visual template.

     */

    virtual void setOwner(IAlfElement* aElement) throw() = 0;

    /**

     * Returns the owner element. Call to this method cannot

     * throw an exception.

     *

     * @see Alf::IAlfElement::setVisualTemplate()

     *

     * @since S60 ?S60_version

     *

     * @return The owner element of a visual template, if this visual template is owned

     *         by an element. NULL if visual template is not owned by an element.

     */

    virtual IAlfElement* owner() const throw() = 0;

    /**

     * Set name of the visual. This name is used when creating

     * concrete visual trees. Name is assigned to each of the produced concrete

     * visuals as a tag. Note thus that all concrete visual

     * trees produced from this visual template share the same tag.

     *

     * @see name()

     *

     * @exception std::bad_alloc thrown if heap memory allocation fails.

     *

     * @since S60 ?S60_version

     *

     * @param aName The name of the visual.

     */

    virtual void setName(const char* aName) = 0;

    /**

     * Returns the name of the visual. Call to this method

     * cannot throw an exception.

     *

     * @see setName()

     *

     * @since S60 ?S60_version

     *

     * @return aName The name of the visual.

     */

    virtual const char* name() const throw() = 0;

    /**

     * Get the number of child visual templates.

     * This returns the number of child visual templates directly

     * under this visual template in the visual template

     * hierarchy. Call to this method cannot throw an exception.

     *

     * @since S60 ?S60_version

     *

     * @return The number of direct child visual templates

     *         under this visual template in the visual template hierarchy.

     */

    virtual int numChildTemplates() const throw() = 0;

    /**

     * Returns a child visual template at a given index.

     *

     * @exception osncore::AlfException thrown with error code osncore::EInvalidArrayIndex if

     *            the index is out of bounds.

     *

     * @since S60 ?S60_version

     *

     * @param aIndex The index of the child visual template.

     *

     * @return Reference to the child visual template object.

     */

    virtual IAlfVisualTemplate& childTemplate(int aIndex) const = 0;

    /**

     * Set the visual type. Every visual template maps to

     * one concrete visual or layout type. Each visual template

     * node in the visual template hierarchy can produce

     * only visuals that match its type. Container nodes

     * in the visual template hierarchy map to layouts

     * and leaf visual template nodes map to visuals.

     *

     * Call to this method will make this visual template 

     * a visual type. The type can thus change from layout

     * type to a visual type.

     *

     * @see setLayoutType()

     * @see visualType()

     * @see layoutType()

     *

     * @since S60 ?S60_version

     *

     * @param aType Type of visual

     */

    virtual void setVisualType(TAlfVisualType aType) = 0;

    /**

     * Get the visual type or a negative integer

     * if this visual template is of layout type.

     * Call to this method cannot throw an exception.

     *

     * @see setVisualType()

     *

     * @since S60 ?S60_version

     *

     * @return Type of visual that this visual template produces

     *         or a negative integer if this visual template

     *         produces layouts.

     */

    virtual int visualType() const throw() = 0;

    /**

     * Set the layout type. Every visual template maps to

     * one concrete visual or layout type. Each visual template

     * node in the visual template hierarchy can produce

     * only visuals that match its type. Container nodes

     * in the visual template hierarchy map to layouts

     * and leaf visual template nodes map to visuals.

     *

     * Call to this method will make this visual template 

     * a layout type. The type can thus change from visual

     * producer to a layout producer.

     *

     * @see setVisualType()

     * @see visualType()

     * @see layoutType()

     *

     * @since S60 ?S60_version

     *

     * @param aType Type of layout

     */

    virtual void setLayoutType(TAlfLayoutType aType) = 0;

    /**

     * Get the layout type or a negative integer

     * if this visual template is of visual type.

     * Call to this method cannot throw an exception.

     *

     * @since S60 ?S60_version

     *

     * @return Type of layout that this visual template produces

     *         or a negative integer if this visual template

     *         produces visuals.

     */

    virtual int layoutType() const throw() = 0;

    /**

     * Adds brush to the brush array.

     *

     * All brushes added to a visual template will be applied to

     * the produced concrete visual when one is produced. The same

     * brush array is shared across all concrete visual instancies

     * created from same visual template.

     * 

     * @see brush()

     * @see numBrushes()

     *

     * @exception std::bad_alloc thrown if a heap memory allocation fails.

     *

     * @since S60 ?S60_version

     *

     * @param aBrush Brush to be added

     */

    virtual void addBrush(CAlfBrush& aBrush) = 0;

    /**

     * Returns the number of brushes in the brush array.

     *

     * @since S60 ?S60_version

     *

     * @return The number of brushes

     */

    virtual int numBrushes() const = 0;

    /**

     * Returns a brush instance from the array of brushes.

     *

     * @see addBrush()

     * @see numBrushes()

     *

     * @exception osncore::AlfException thrown with error code osncore::EInvalidArrayIndex if

     *            the given index is out of bounds.

     *     

     * @since S60 ?S60_version

     *

     * @param aIndex The index into the array of brushes.

     *

     * @return Reference to the brush object instance at the given array index.

     */

    virtual CAlfBrush& brush(int aIndex) const = 0;

    /**

     * Enables or disables selected child mode. By default

     * this is disabled and thus visual template creates or updates

     * all its children when createVisualTree() or updateVisualTree()

     * is called. If selected child mode is enabled the visual template 

     * will create or update only the selected child. The child which 

     * is affected in selected child mode is determined in the data passed

     * in the createVisualTree() or updateVisualTree() method. In the 

     * passed data map a search is done to match the child index 

     * field name with the keys in the map. If an entry is found its value

     * is used as an index to determine the child branch that is to be 

     * created or updated.

     *

     * @see createVisualTree()

     * @see updateVisualTree()

     *

     * @since S60 ?S60_version

     *

     * @param aSelectChild Set to true to enable the child mode or false to disable the child mode.

     * @param aChildIndFieldName Key in data map, from which entry the index of

     *                           the selected child is fetched.

     */

    virtual void setSelectChildMode(bool aSelectChild, const UString& aChildIndFieldName) = 0;

    /**

     * Add a child visual template. The visual templates may form

     * a tree structure to create and update a visual tree. The visuals

     * created by children are added to the layout created by this

     * visual template. This visual template acquires the ownership for the

     * child visual template passed as an argument.

     *

     * If a visual template added as a child to this visual template is owned

     * by an Alf::IAlfElement the connection between the child visual template

     * and its owner element is implicitly removed in this call when a 

     * parent-child connection is created. Effectively having a parent visual

     * template or being owned by an element are mutually exclusive properties

     * for a visual template. Elements can own only root visual templates and

     * if an owned root visual template becomes a child of another visual 

     * template the visual template will be removed from the associated owner

     * element.

     *

     * @see insertChildTemplate()

     *

     * @exception std::bad_alloc Thrown if memory allocation fails in appending the child

     *            visual template to child array of this visual template.

     * @exception osncore::AlfException thrown with error code osncore::EInvalidHierarchy if

     *            the call to this method would result in an invalid visual template hierarchy.

     *            This can occur if a child is added to a non-layout visual template or if a

     *            call would result in a parent becoming a descendant of it's child (a recursive

     *            tree).

     *

     * @since S60 ?S60_version

     *

     * @param aChild Child visual template to be appended to the children of this visual template.

     */

    virtual void addChildTemplate(IAlfVisualTemplate& aChild) = 0;

    /**

     * Inserts a child visual template at given index. The visual templates may form

     * a tree structure to create and update a concrete visual tree. The concrete visuals

     * created by children are added to the layout created by this

     * visual template. This visual template acquires the ownership of the inserted

     * child visual template.

     *

     * @see addChildTemplate()

     *     

     * @exception std::bad_alloc thrown if memory allocation fails in inserting the child visual

     *            template to the child list of this visual template.

     * @exception osncore::AlfException thrown with error code osncore::EInvalidArrayIndex when

     *            index supplied is out of range for array of visual templates.

     * @exception osncore::AlfException thrown with error code osncore::EInvalidHierarchy if

     *            the call to this method would result in an invalid visual template hierarchy.

     *            This can occur if a child is added to a non-layout visual template or if a

     *            call would result in a parent becoming a descendant of it's child (a recursive

     *            tree) or if the same child visual template is added to the hierarchy twice.

     *

     * @since S60 ?S60_version

     *

     * @param aChild  The child visual template.

     * @param aIndex  Position at which child template is to be added.

     */

    virtual void insertChildTemplate(IAlfVisualTemplate& aChild, int aIndex) = 0;

    /**

     * Removes and destroyes a child visual template from an index in the child list

     * of this visual template. This will recursively also destroy all child visual templates

     * in the hierarchy below the destroyed child visual template. This call is silently

     * ignored if the index is out of bounds. Call to this method cannot throw an

     * exception.

     *

     * @since S60 ?S60_version

     *

     * @param aIndex Position from which child visual template is to be removed.

     */

    virtual void destroyChildTemplate(int aIndex) throw() = 0;

    /**

     * Destroyes a child visual template with the given name and removes it from the children

     * of this visual template. This will recursively also destroy all child visual templates

     * in the hierarchy below the destroyed child visual template. This call is silently

     * ignored if a child visual template with the given name is not found. Call

     * to this method cannot throw an exception.

     *

     * @since S60 ?S60_version

     *

     * @param aName Name of child visual template to be destroyed.

     */

    virtual void destroyChildTemplate(const char* aName) throw() = 0;

    /**

     * Update an existing concrete visual tree with new values. The existing visual tree

     * should be produced from this visual template hierarchy using the createVisualTree() -

     * method.

     * 

     * @see createVisualTree()

     * @see setSelectChildMode()

     * @see addAttributeSetter()

     *

     * @since S60 ?S60_version

     *

     * @param aData A map containing new data for the visuals.

     * @param aOldData Old data, that will be replaced. This is used to for instance tear down

     *                 the old selected child branch before creating a new branch in the selected

     *                 child mode.

     * @param aVisual The root of the concrete visual tree that will be updated. This root visual

     *                needs to match this visual template and should have been created using this

     *                visual template.

     * @return Root visual of the updated concrete visual tree.

     */

    virtual CAlfVisual* updateVisualTree(IAlfMap* aData, IAlfMap* aOldData, CAlfVisual& aVisual) = 0;

    /**

     * Creates a new concrete visual tree from this visual template hierarchy and initializes the visuals.

     * Created visual tree matches the visual template hierarchy under this visual template.

     *

     * @see updateVisualTree()

     * @see setSelectChildMode()

     * @see addAttributeSetter()

     *

     * @since S60 ?S60_version

     *

     * @param aControl The owner control of the new concrete visual hierarchy.

     * @param aData A map containing data for the visuals. This is used to set the attributes of the

     *              produced concrete visuals using the attribute containers and attribute setters

     *              added through the addAttributeSetter() - method.

     * @param aParentLayout Concrete layout visual to insert the created concrete visual tree into.

     *                      Parent layout for a created visual.

     * @param aLayoutIndex Ordinal index, into where the created visual should be placed in the parent layout.

     *

     * @return Pointer to the root visual object of the concrete visual hierarchy that was constructed.

     */

    virtual CAlfVisual* createVisualTree(CAlfControl& aControl,

                                         IAlfMap* aData, CAlfLayout* aParentLayout, int aLayoutIndex) = 0;

    /**

     * Add a new attribute setter and associated attribute container to set visual attributes

     * of the concrete visual hierarchies created or updated with this visual template hierarchy.

     * This visual template object acquires ownership of both the passed attribute setter as well

     * as the attribute container. Attribute containers in a visual template are iterated through

     * whenever concrete visual trees are created or updated. Concrete visual tree attributes

     * are set from the data passed in through the createVisualTree() and updateVisualTree() methods

     * using the attribute setters and containers added into the visual template using this method.

     *

     * @see createVisualTree()

     * @see updateVisualTree()

     *

     * @exception std::bad_alloc thrown if heap memory allocation fails.

     *

     * @since S60 ?S60_version

     *

     * @param aSetter Attribute setter that will be used to set the attributes in the passed in

     *                container to concrete visuals.

     * @param aContainer Container holding the attribute value used by the attribute setter.

     */

    virtual void addAttributeSetter(IAlfAttributeSetter* aSetter, AlfAttributeContainer* aContainer) = 0;

    /**

     * Get the number of the attribute setters and the corresponding attribute containers.

     * Call to this method cannot throw an exception.

     *

     * @since S60 ?S60_version

     *

     * @return The number of the attribute setters and containers.

     */

    virtual int numAttributeSetters() const throw() = 0;

    /**

     * Returns an attribute setter maintained in this visual template from the given index.

     *

     * @exception osncore::AlfException thrown with error code osncore::EInvalidArrayIndex if

     *            the given index is out of bounds.

     *

     * @since S60 ?S60_version

     *

     * @param aIndex The index of the visual attribute setter.

     * @return Reference to the attribute setter object.

     */

    virtual IAlfAttributeSetter& attributeSetter(int aIndex) const = 0;

    /**

     * Returns an attribute container maintained in this visual template from the given index.

     *

     * @exception osncore::AlfException thrown with error code osncore::EInvalidArrayIndex if

     *            the given index is out of bounds.

     *

     * @since S60 ?S60_version

     *

     * @param aIndex The index of the visual attribute container.

     * @return Reference to the attribute container object.

     */

    virtual AlfAttributeContainer& attributeContainer(int aIndex) const = 0;

    /**

     * Retrieves pointer to the parent visual template.

     * Returns NULL if this is a root visual template of a visual template

     * hierarchy. Call to this method cannot throw an exception.

     *

     * @see addChildTemplate()