/*

* Copyright (c) 2002 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: 

*     Utility class for HTML converter

*

*/

#ifndef CMSGMAILVIEWERHTMLCONV_H

#define CMSGMAILVIEWERHTMLCONV_H

//  INCLUDES

#include <e32base.h>

#include <txtrich.h>

// FORWARD DECLARATIONS

class CMsgBodyControl;

class CCnvCharacterSetConverter;

// CLASS DECLARATION

/**

*  Utility class for HTML converter. 

*  A pair of two strings.

*/

class CStringPair : public CBase

    {

    public:

        /**

        * A constructor.

        * @param aName a HTML macro, e.g. lt

        * @param aValue a character that is represented by a macro e.g. <

        * @return created object.

        */

        static CStringPair* NewLC(const TDesC& aName, const TDesC& aValue);

        /**

        * Destructor

        */

        ~CStringPair();

        /**

        * @return a name of the macro

        */

        HBufC* GetName() const;

        /**

        * @return a value of the macro

        */

        HBufC* GetValue() const;

        /**

        * Compares if two pairs are same. Names are compared.

        * @return as in TBufC::Compare.

        */

        static TInt Compare(const CStringPair& aPair1, 

            const CStringPair& aPair2);

    private:

        /**

        * A constructor        

        */

        CStringPair();

        /**

        * A 2nd phase constructor

        * @param aName a HTML macro, e.g. lt

        * @param aValue a character that is represented by a macro e.g. <

        */

        void ConstructL(const TDesC& aName, const TDesC& aValue);

    private:

        /// Name of the macro. Owns.

        HBufC* iName;

        /// Value of the macro. Owns.

        HBufC* iValue;

    };

/**

*  HTML converter.

*  This class is used in Mail viewer application to convert

*  messages with HTML-formatting to plain text.

*/

class CMsgMailViewerHtmlConv : public CActive

    {

    public:  // Constructors and destructor                

        /**

        * Two-phased constructor.

        * @param aHandle a handle to HTML-file.

        * @param aCharset Characterset ID

        * @param aForced forse converter to use passed Character set id

        * otherwise converter tries to use character set defined in HTML content

        * If zero character set id is tried to find out from the HTML content.

        */            

        static CMsgMailViewerHtmlConv* NewLC(

        	RFile& aHandle, TUint aCharset, TBool aForced);

        static CMsgMailViewerHtmlConv* NewL(

            RFile& aHandle, TUint aCharset, TBool aForced);

        /**

        * Destructor.

        */

        virtual ~CMsgMailViewerHtmlConv();

    public: // New functions

        /**

        * Removes HTML-tags and replaces macros with real characters.

        * @return KErrNone if part of the conversion has been successful.

        * Returns KErrEof when conversion is done.

        */

        TInt Convert();

        /**

        * Removes HTML-tags and replaces macros with real characters.  

        * Does the conversion asynchronously in low priority.

        * 

        * @param aStatus Generic request status.

        *        KErrNone when the convertion is succesful. 

        *        Other error codes are used to indicate an error during conversion. 

        */

        void Convert( TRequestStatus* aStatus );

        /**

        * Returns a stripped text.

        * @return stripped text object.

        */

        HBufC* GetText() const;

        /**

        * Return file id array of inline images.

        * @return Reference to array.

        * Ownership is transferred to caller

        **/

        RPointerArray<HBufC>* FileIdArray();       

        /**

        * Checks if the charset name and identifiers were autoparsed

        */

        TBool AutoParsedCharSetNameAndIdentifier() const;

        /**

        * Returns the auto parsed charset identifier

        */

        TUint AutoParsedCharSetIdentifier() const;    

    private:

        /**

        * C++ default constructor.

        */

        CMsgMailViewerHtmlConv();

        /**

        * By default Symbian OS constructor is private.

        * @param aHandle file handle to HTML content

        * @param aCharSet characterset id

        */

        void ConstructL(RFile& aHandle, TUint aCharSet);

        /**

        * Deletes aLen characters beginning from aPos in iStrippedText.

        * @param aLen how many characters will be deleted.

        * @return New length of the message.

        */

        TInt Delete(const TInt aLen);

        /**

        * Inserts characters beginning from aPos in iStrippedText.

        * @param aChars characters to be inserted.

        * @return New length of the message.

        */

        TInt InsertTextL(const TDesC& aChars);

        /**

        * Replaces macro with real text

        * @return New length of the message.

        */

        TInt ReplaceMacroL();

        /**

        * Fills a map of macros with name, value pairs.

        */

        void InitMacroArrayL();

        /**

        * Converts unnumbered list to a text.

        * @param Indentation of the items.

        * @return New length of the message.

        */

        TInt HandleUListL(const TInt aIndent);

        /**

        * Converts ordinal list to a text.

        * @param Indentation of the items.

        * @return New length of the message.

        */

        TInt HandleOListL(const TInt aIndent);

        /**

        * Converts definition list to a text.

        * @param Indentation of the items.

        * @return New length of the message.

        */

        TInt HandleDListL(const TInt aIndent);

        /**

        * Converts lists into a text.

        * @param aIndent Indentation of the items

        * @param aNumbered, ETrue if ordinal list, EFalse otherwise

        * @return New length of the message

        */

        TInt HandleListL(const TInt aIndent, const TBool aNumbered);

        /**

        * Converts HTML tags to plain text.

        * @param indentation of the lists.

        * @return New length of the message.

        */

        TInt HandleTagL(const TInt aIndent);

        /**

        * Removes characters from iPos to >-character. Shows an error

        * and interrupts conversion if it is not found.

        * @return New length of the message.

        */

        TInt RemoveTagL();

        /**

        * Adds an error message to end of the message 

        * and shows an information note.

        */

        void ShowErrorL();

        /**

        * Adds a linefeed into a text.

        */

        void InsertLinefeedL();

        /**

        * Performs a character conversion for area started with 

        * BeginConvertL();

        */

        void DoConvertL();

        /**

        * Main loop

        */

        void DoConversionL();

        /**

         * Continue asynchronous conversion in next scheduler loop

         */

        void ContinueAsyncConvert();

    protected: // From CActive

        void RunL();

        void DoCancel();

    private:    // Data

        /**

        * Contains a text read from file which is stripped (Owned).

        */

        HBufC *iOrigText;

        /**

        * A position in text.

        */

        TInt iPos;

        /**

        * An array which contains all HTML macro definitions which

        * are read from a resource file.

        */

        RPointerArray<CStringPair> *iMacros;

        /**

        * An array which contains places for line feeds. These will 

        * be inserted to a RTF object.

        */

        RArray<TInt> *iNewLines;

        /**

        * Status of the conversion

        */

        TInt iReturnValue;

        /**

        * Position where an error occured

        */

        TInt iErrorPos;

        /**

        * Own: Character converter instance.

        */

        CCnvCharacterSetConverter* iCharConv;

        /**

        * State conversion is in.

        */

        TInt iConversionState;

        /**

        * An array containing inline image names

        */

        RPointerArray<HBufC>* iFileIdArray;

        /**

        * Characterset name

        */

        HBufC* iCharSetName;

        /**

        * Characterset id

        */

        TUint iCharacterSetId;

        /**

        * Status flags

        */

        TUint iStatusFlags;

        /**

         * Asynchronous convert request status 

         */

        TRequestStatus* iReqStatus;

    };

#include "MsgMailViewerHtmlConv.inl" // inline functions

#endif      // CMSGMAILVIEWERHTMLCONV_H

// End of File