/*

 * Copyright (c) 2000-2009 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 EDITORUNDO_H_

 #define EDITORUNDO_H_

 #include "unified_editor.h"

 namespace UndoSystem

 /**

 @internalTechnology

 */

 {

 class CCommandManager;

 class MNotUndoableGatekeeper;

 }

 class CEditorCommandFactory;

 /**

 MUnifiedEditor decorator that adds undo functionality.

 It passes commands transparently to the editor it is constructed upon, while

 storing the operations so that they can be undone and redone. Calling a

 non-const method of MUnifiedEditor wipes all 'Redo' operations.

 The undo and redo operations are only guaranteed to be accurate if the

 underlying editor satisfies certain conditions.

 @since App-frameworks6.1

 @internalAll

 */

 class CEditorWithUndo : public CBase,

 	public MUnifiedEditor,

 	private MUnifiedEditor::MStyleSupport,

 	private MUnifiedEditor::MPictureSupport,

 	private MUnifiedEditor::MClipboardSupport

 	{

 public:

 	~CEditorWithUndo();

 	/**

 	 * Creates a CEditorWithUndo. It does not own the aEditor.

 	 */

 	IMPORT_C static CEditorWithUndo* NewL(MUnifiedEditor& aEditor);

 	/**

 	 * Creates a CEditorWithUndo, using the aSharedUndoSystem. This allows

 	 * many objects to stay in synchronization when each is accessed

 	 * seperately.

 	 * The aEditor is not owned.

 	 */

 	IMPORT_C static CEditorWithUndo* NewL(MUnifiedEditor& aEditor,

 		UndoSystem::CCommandManager* aSharedUndoSystem);

 	/**

 	 * Undoes one operation or batch of operations. If one operation in the

 	 * middle of a batch leaves, this function will leave, but the underlying

 	 * editor will not necessarily be in the same state as it was in before

 	 * the call. However, all operations will still be stored, and so the

 	 * previous state is still recoverable with a call to RedoL() or a

 	 * further call to UndoL will complete the operation (resource acquisition

 	 * permitting).

 	 */

 	IMPORT_C void UndoL();

 	/**

 	 * Redoes one operation or batch of operations. If one operation in the

 	 * middle of a batch leaves, this function will leave, but the underlying

 	 * editor will not necessarily be in the same state as it was in before

 	 * the call. However, all operations will still be stored, and so the

 	 * previous state is still recoverable with a call to UndoL() or a

 	 * further call to RedoL will complete the operation (resource acquisition

 	 * permitting).

 	 */

 	IMPORT_C void RedoL();

 	/**

 	 * Returns ETrue iff UndoL() would have an effect

 	 */

 	IMPORT_C TBool CanUndo() const;

 	/**

 	 * Returns ETrue iff RedoL() would have an effect

 	 */

 	IMPORT_C TBool CanRedo() const;

 	/**

 	 * Wipes all undo and redo operations

 	 */

 	IMPORT_C void ResetUndo();

 	/**

 	 * Sets limits on the 'undo depth'. This is the numbet of times that

 	 * successive calls to UndoL() have an effect. When a depth of

 	 * aMaxItems is reached, the undo depth is reset to aMinItems.

 	 */

 	IMPORT_C void SetMaxItems(TInt aMaxItems);

 	/**

 	 * Sets a gatekeper for the undo system. This will be called whenever an

 	 * operation is attempted that cannot be undone for any reason.

 	 * The gatekeeper therefore has an oportunity to suppress execution and

 	 * keep the current undo operations stored.

 	 * NULL may be passed to restore default behaviour.

 	 * Returns the old gatekeeper.

 	 */

 	IMPORT_C UndoSystem::MNotUndoableGatekeeper*

 		SetGatekeeper(UndoSystem::MNotUndoableGatekeeper*);

 	// From MUnifiedEditor

 	MTmOptionalInterface* Interface(TUint aId);

 	void InsertTextL(TInt aPos, const TDesC& aText, const TDesC* aStyle,

 		const TTmCharFormatLayer*, const RTmParFormatLayer*);

 	void DeleteTextL(TInt aPos,TInt aLength);

 	void SetBaseFormatL(const TTmCharFormat&, const RTmParFormat&);

 	void SetCharFormatL(TInt aPos, TInt aLength, const TTmCharFormatLayer&);

 	void SetParFormatL(TInt aPos, TInt aLength, const RTmParFormatLayer&);

 	void DeleteCharFormatL(TInt aPos, TInt aLength);

 	void DeleteParFormatL(TInt aPos, TInt aLength);

 	TInt DocumentLength() const;

 	void GetText(TInt aPos, TPtrC& aText) const;

 	void GetBaseFormatL(TTmCharFormat&, RTmParFormat&) const;

 	void GetCharFormat(TInt aPos, TFormatLevel aLevel,

 		TTmCharFormatLayer& aFormat,TInt& aRunLength) const;

 	void GetParFormatL(TInt aPos, TFormatLevel aLevel,

 		RTmParFormatLayer& aFormat, TInt& aRunLength) const;

 private:

 	// from MStyleSupport

 	TInt CreateStyleL(const RTmStyle&);

 	TInt ChangeStyleL(const RTmStyle&);

 	TInt SetStyleL(TInt aPos, TInt aLength, const TDesC&);

 	TInt RenameStyleL(const TDesC& aOldName, const TDesC& aNewName);

 	TInt DeleteStyleL(const TDesC& aName);

 	TInt StyleCount() const;

 	void GetStyle(TInt aPos, TPtrC& aName, TInt& aRunLength) const;

 	TInt GetStyleByNameL(const TDesC& aName, RTmStyle&) const;

 	TInt GetStyleByIndexL(TInt aIndex, RTmStyle&) const;

 	// from MPictureSupport

 	void InsertPictureL(TInt aPos, const TPictureHeader&);

 	void DropPictureL(TInt aPos);

 	void Picture(TInt aPos, TPictureHeader&) const;

 	// from MClipboardSupport

 	void CopyToStoreL(CStreamStore& aStore, CStreamDictionary& aDictionary,

 		TInt aPos, TInt aLength) const;

 	void PasteFromStoreL(const CStreamStore& aStore,

 		const CStreamDictionary& aDictionary, TInt aPos);

 	CEditorWithUndo();

 	void ConstructL(MUnifiedEditor& aEditorBasedOn,

 		UndoSystem::CCommandManager* aSharedUndoSystem);

 	CEditorCommandFactory*			iFactory;

 	MUnifiedEditor*						iBaseEditor;

 	UndoSystem::CCommandManager*	iCommandManager;

 	};

 #endif	// EDITORUNDO_H_