/*

* 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:   Handles VPN command file parsing.

*

*/

#ifndef C_VPNCOMMANDFILEPARSER_H

#define C_VPNCOMMANDFILEPARSER_H

#include <e32base.h>

/**

 * Parser utility class for VPN command file (.vpn).

 * Public interface offers functions for parsing

 * and querying the parsed values. 

 * Internal implementation parses XML tree and extracts

 * found parameters to local container.

 *

 */

class CCmdFileParser : public CBase 

    {

// C'tors

public:

    /**

     * No need for two-phased construction

     */

    CCmdFileParser();

    ~CCmdFileParser();

// Public functions

public:

    /**

     * Parse an XML file and store parsed variables to local

     * structures.

     *

     * @param aInputData XML file in 8bit desc buffer.

     *

     * @leave Leaves with KErrCorrupt, if the data is not in 

     *        expected format.

     */

    void    ParseL(const TDesC8& aInputData);

    /**

     * Returns the a parsed string value. Control of the instantiated

     * object is transferred to the caller. If no value is found,

     * returns a NULL object.

     *

     * @param aUri The "full uri" of the requested value

     *

     * @ret HBufC* A pointer to a newly allocated 16bit descriptor containing

     *      the parsed value, or NULL if none found.

     *

     * @leave Leaves in case 

     */

    HBufC*  GetParsedValueStrL(const TDesC8& aUri);

    /**

     * Translates a parsed value to TInt and returns it.

     * Leaves if the operation cannot be accomplished.

     *

     * @param aUri The "full uri" of the requested value

     * @param aVal Used for TInt return value (if any)

     *

     * @leave Leaves if the operation fails.

     */

    void    GetParsedValueIntL(const TDesC8& aUri, TInt& aVal);

    /**

     * Translates a parsed value to TBool and returns it.

     * Leaves if the operation cannot be accomplished.

     *

     * @param aUri The "full uri" of the requested value

     * @param aVal Used for TBool return value (if any)

     *

     * @leave Leaves if the operation fails.

     */

    void    GetParsedValueBoolL(const TDesC8& aUri, TBool& aVal);

private:

    void    ReleaseResources();

    /**

     * Parse the input XML

     *

     */

    void    ParseXmlL(const TDesC8& aInputData);

    /**

     * Checks whether the encountered "closing" XML node is indeed 

     * the most recently opened.

     *

     * @param aName The name to check

     *

     * @return ETrue, iff the given name was found on the top 

     *         of the iParserStack

     *

     */

    TBool       IsTopmostNode(const TDesC8& aName) const;

    /**

     * Pushes an "opening" XML node on the parser stack. 

     * Instantiates a new stack object based on the given name.

     *

     * @param aName The name of the object to push

     *

     * @leave Leaves if OOM.

     */

    void        PushNodeL(const TDesC8& aName);

    /**

     * Pops the topmost node from the parser stack. 

     * No questions asked.

     *

     */

    void        PopNode();

    /**

     * Constructs a new string, containing the full "URI"

     * for the given text. It is assumed that the text is

     * located inside the node that is currently open (i.e.

     * on the top of the parser stack).

     * URI is of form "root/branch1/branch6/aText".

     *

     * @aText The text in the leafnode -- the last segment 

     *        of the uri

     *

     * @return Returns a new string containing the full uri

     *         of the leaf (text) node.

     *

     * @leave Leaves if OOM

     *

     */

    HBufC8*     ParseTreeUriL(const TDesC8& aText) const;

    /**

     * Checks whether the text segment in XML is valid. 

     * If it begins with CR/LF, it's not.

     *

     * @param aText The text to verify.

     *

     * @return ETrue only if the text is valid in that

     *         it's not a string beginning with CR/LF

     *

     */

    TBool       IsValidText(const TDesC8& aText) const;

    /**

     * Iterates through parsed values array and checks whether

     * the given URI is found. If it is, returns the leaf

     * value of the uri.

     * URI here must end with slash ("/"), so it must not contain

     * the related leaf node itself (representing the parameter's 

     * textual value).

     * Example: FindUri("root/node1/node2/") will return "666"

     * if there exists a URI "root/node1/node2/666" in the parsed

     * values array.

     *

     * @return A pointer to the found value or KNullDesC8 if none

     *         was found. 

     * 

     */

    TPtrC8      FindUri(const TDesC8& aUri) const;

// Private variables

private:

    HBufC*                          iFileName;

    HBufC*                          iFileContents;

    HBufC*                          iPKCS12Pwd;

    TInt                            iDevLockPolicy;

    TBool                           iDevLockRequired;

    TBool                           iParseReady;

    // Parser stack consisting of parse tree nodes

    CArrayFixFlat<HBufC8*>*         iParserStack;

    // Parsed stack, consisting of leaf values and their full

    // tree paths (root/branch1/branch6/leaf_value)

    CArrayFixFlat<HBufC8*>*         iParsedValuesArray;

    };

#endif // C_VPNPOLICYINSTALLER_H