/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

/*
 * XSEC
 *
 * DSIGTransformC14n := Class that holds information about C14n transforms
 *
 * $Id$
 *
 */

#include <xsec/dsig/DSIGTransform.hpp>

/**
 * @ingroup pubsig
 */

/**
 * @brief Transform holder for C14n based transforms.
 *
 * The DSIGTransformC14n class is used to hold C14n \<Transform\> elements
 * within a document.  This includes Exclusive and Comment options
 *
 *
 * @see TXFMC14n
 * @see DSIGTransform
 *
 */

class XSEC_EXPORT DSIGTransformC14n : public DSIGTransform {

public:

    /** @name Constructors and Destructors */
    //@{

    /**
     * \brief Contructor used for existing XML signatures.
     *
     * The Node structure already exists, so read the nodes in.
     *
     * @param env The operating environment
     * @param node The DOM node (within doc) that is to be used as the base of the Transform.
     * @see #load
     */

    DSIGTransformC14n(const XSECEnv* env, XERCES_CPP_NAMESPACE_QUALIFIER DOMNode* node);

    /**
     * \brief Contructor used for new signatures.
     *
     * The Node structure will have to be created.
     *
     * @note DSIGTransform structures should only ever be created via calls to a
     * DSIGTransformList object.
     *
     * @param env The operating environment
     * @see createBlankTransform
     */

    DSIGTransformC14n(const XSECEnv* env);

    /**
     * \brief Destructor.
     *
     * Destroy the DSIGSignature elements.
     *
     * Does not destroy any associated DOM Nodes
     */

    virtual ~DSIGTransformC14n();

    //@}

    /** @name Interface Methods */

    //@{

    /**
     * \brief Create the Canonicalising transformer element.
     *
     * Implemented by each Transform class and used by the DSIGSignature
     * when consructing a TXFM List that includes canonicalisation (nearly always)
     */

    virtual void appendTransformer(TXFMChain* input);

    /**
     * \brief Construct blank Canonicalisation Transform element.
     *
     * Instruct the implementation to create the required
     * transform and return the newly constructed DOMNode structure
     *
     * @note By default creates a non-comment non-exclusive C14n transform.
     */

    virtual XERCES_CPP_NAMESPACE_QUALIFIER DOMElement* createBlankTransform(
        XERCES_CPP_NAMESPACE_QUALIFIER DOMDocument* parentDoc);

    /**
     * \brief Load a DOM structure
     *
     * (Re)read the DOM structure into the Signature structures
     *
     */

    virtual void load();

    //@}

    /** @name C14n Specific Methods */

    //@{

    /**
     * \brief Set canonicalization method.
     *
     * Set the canonicalization method to the type indicated.  If this changes
     * the transform from Exclusive to Standard C14n, any associated
     * InclusiveNamespaces children will be removed.
     *
     * If this is moving from one form of Exclusive to another, any InclusiveNamespace
     * children will remain.
     *
     * @param uri Type of canonicalizer required.
     */

    void setCanonicalizationMethod(const XMLCh* uri);

    /**
     * \brief Get canonicalization method.
     *
     * Return the type of canonicalization to the caller.
     *
     * @returns Canonicalization type.
     */

    const XMLCh* getCanonicalizationMethod() const;

    /**
     * \brief Add a namespace prefix to the InclusiveNamespaces list
     *
     * Exclusive canonicalization includes the ability to define a PrefixList of
     * namespace prefixes that will not be treated exclusively, rather they will
     * be handled as per normal C14n.
     *
     * This function allows a caller to add a prefix to this list
     * @param ns The prefix to add.
     */

    void addInclusiveNamespace(const char* ns);

    /**
     * \brief Set the namespace list
     *
     * Deletes current PrefixList (if any) and sets the list to the space
     * separated list of namespace prefixes provided in ns.
     *
     * @note No checking is done on the string passed in.
     *
     * @param ns The (space separated) list of prefixes to set.
     */

    void setInclusiveNamespaces(const XMLCh* ns);

    /**
     * \brief Get the string containing the inclusive namespaces.
     *
     * Get the string containing a list of (space separated) prefixes that will
     * be handled non-exclusively in an exclusive C14n transform.
     *
     * @returns A pointer to the string held in the node (NULL if no namespaces defined).
     * @note The pointer returned is owned by the Transform structure - do not delete.
     */

     const XMLCh* getPrefixList() const;

     /**
      * \brief Delete all inclusive namespaces.
      *
      * Deletes the structures (including the DOM nodes) that hold the inclusive
      * namespaces list.
      */

     void clearInclusiveNamespaces();

    //@}

private:
    DSIGTransformC14n();
    DSIGTransformC14n(const DSIGTransformC14n& theOther);

    void createInclusiveNamespaceNode();

    const XMLCh* m_cMethod;                                     // The method
    XERCES_CPP_NAMESPACE_QUALIFIER DOMElement* mp_inclNSNode;   // Node holding the inclusive Namespaces
    const XMLCh* mp_inclNSStr;                                  // String holding the namespaces

    bool m_exclusive;                                           // C14N method characteristics
    bool m_comments;
    bool m_onedotone;
};