/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (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.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Mozilla XForms support.
 *
 * The Initial Developer of the Original Code is
 * IBM Corporation.
 * Portions created by the Initial Developer are Copyright (C) 2004
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *  Brian Ryner <bryner@brianryner.com>
 *  Allan Beaufour <abeaufour@novell.com>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

#ifndef nsXFormsUtils_h_
#define nsXFormsUtils_h_

#include "prtypes.h"
#include "nsCOMPtr.h"
#include "nsIDOMXPathResult.h"

class nsIDOMNode;
class nsIDOMElement;
class nsIXFormsModelElement;
class nsIURI;
class nsString;

#define NS_NAMESPACE_XFORMS              "http://www.w3.org/2002/xforms"
#define NS_NAMESPACE_XHTML               "http://www.w3.org/1999/xhtml"
#define NS_NAMESPACE_XML_SCHEMA          "http://www.w3.org/2001/XMLSchema"
#define NS_NAMESPACE_XML_SCHEMA_INSTANCE "http://www.w3.org/2001/XMLSchema-instance"

/**
 * XForms event types
 *
 * @see http://www.w3.org/TR/xforms/slice4.html#rpm-events
 */

enum nsXFormsEvent {
  eEvent_ModelConstruct,
  eEvent_ModelConstructDone,
  eEvent_Ready,
  eEvent_ModelDestruct,
  eEvent_Previous,
  eEvent_Next,
  eEvent_Focus,
  eEvent_Help,
  eEvent_Hint,
  eEvent_Rebuild,
  eEvent_Refresh,
  eEvent_Revalidate,
  eEvent_Recalculate,
  eEvent_Reset,
  eEvent_Submit,
  eEvent_DOMActivate,
  eEvent_ValueChanged,
  eEvent_Select,
  eEvent_Deselect,
  eEvent_ScrollFirst,
  eEvent_ScrollLast,
  eEvent_Insert,
  eEvent_Delete,
  eEvent_Valid,
  eEvent_Invalid,
  eEvent_DOMFocusIn,
  eEvent_DOMFocusOut,
  eEvent_Readonly,
  eEvent_Readwrite,
  eEvent_Required,
  eEvent_Optional,
  eEvent_Enabled,
  eEvent_Disabled,
  eEvent_InRange,
  eEvent_OutOfRange,
  eEvent_SubmitDone,
  eEvent_SubmitError,
  eEvent_BindingException,
  eEvent_LinkException,
  eEvent_LinkError,
  eEvent_ComputeException
};

/**
 * This class has static helper methods that don't fit into a specific place
 * in the class hierarchy.
 */
class nsXFormsUtils
{
public:

  /**
   * Possible values for any |aElementFlags| parameters.  These may be
   * bitwise OR'd together.
   */
  enum {
    /**
     * The element has a "model" attribute.
     */
    ELEMENT_WITH_MODEL_ATTR = 1 << 0
  };

  /**
   * Initialize nsXFormsUtils.
   */
  static NS_HIDDEN_(nsresult)
    Init();

  /**
   * Locate the model that is a parent of |aElement|.  This method walks up the
   * content tree looking for the containing model.
   */
  static NS_HIDDEN_(void)
    GetParentModel(nsIDOMElement *aElement, nsIDOMNode **aModel);

  /**
   * Find the evaluation context for an element.
   *
   * That is, the model it is bound to (|aModel|), and if applicable the
   * \<bind\> element that it uses (|aBindElement| and the context node
   * (|aContextNode|).
   *
   * @param aElement          The element
   * @param aElementFlags     Flags describing characteristics of aElement
   * @param aModel            The \<model\> for the element
   * @param aBindElement      The \<bind\> the element is bound to (if any)
   * @param aContextNode      The context node for the element
   */
  static NS_HIDDEN_(nsresult)
    GetNodeContext(nsIDOMElement  *aElement,
                   PRUint32        aElementFlags,
                   nsIDOMNode    **aModel,
                   nsIDOMElement **aBindElement,
                   nsIDOMElement **aContextNode,
                   PRInt32        *aContextPosition = nsnull,
                   PRInt32        *aContextSize = nsnull);

  /**
   * Locate the model for an element.
   *
   * @note Actually it is just a shortcut for GetNodeContext().
   *
   * @param aElement          The element
   * @param aElementFlags     Flags describing characteristics of aElement
   * @return                  The model
   */
  static NS_HIDDEN_(already_AddRefed<nsIDOMNode>)
    GetModel(nsIDOMElement  *aElement,
             PRUint32        aElementFlags = ELEMENT_WITH_MODEL_ATTR);

  /**
   * Evaluate a 'bind' or |aBindingAttr| attribute on |aElement|.
   * |aResultType| is used as the desired result type for the XPath evaluation.
   * The model and bind elements (if applicable) are located as part of this
   * evaluation, and are returned (addrefed) in |aModel| and |aBind|.
   *
   * The return value is an XPathResult as returned from
   * nsIDOMXPathEvaluator::Evaluate().
   */
  static NS_HIDDEN_(already_AddRefed<nsIDOMXPathResult>)
    EvaluateNodeBinding(nsIDOMElement  *aElement,
                        PRUint32        aElementFlags,
                        const nsString &aBindingAttr,
                        const nsString &aDefaultRef,
                        PRUint16        aResultType,
                        nsIDOMNode    **aModel,
                        nsIDOMElement **aBind);


  /**
   * Given a bind element |aElement|, return the nodeset that it applies to.
   * |aResultType| is used as the desired result type for the XPath
   * evaluation.
   */
  static NS_HIDDEN_(already_AddRefed<nsIDOMXPathResult>)
    EvaluateNodeset(nsIDOMElement *aElement, PRUint16 aResultType);

  /**
   * Given a bind element |aElement|, find the context node to be used
   * for evaluating its nodeset.
   */
  static NS_HIDDEN_(already_AddRefed<nsIDOMNode>)
    FindBindContext(nsIDOMElement         *aBindElement,
                    nsIXFormsModelElement *aModelElement);

  /**
   * Convenience method for doing XPath evaluations.  This gets a
   * nsIDOMXPathEvaluator from |aContextNode|'s ownerDocument, and calls
   * nsIDOMXPathEvaluator::Evalute using the given expression, context node,
   * namespace resolver, and result type.
   */
  static NS_HIDDEN_(already_AddRefed<nsIDOMXPathResult>)
    EvaluateXPath(const nsAString &aExpression,
                  nsIDOMNode      *aContextNode,
                  nsIDOMNode      *aResolverNode,
                  PRUint16         aResultType,
                  PRInt32          aContextPosition = 1,
                  PRInt32          aContextSize = 1);

  /**
   * Given a node in the instance data, get its string value according
   * to section 8.1.1 of the XForms specification.
   */
  static NS_HIDDEN_(void) GetNodeValue(nsIDOMNode *aDataNode,
                                       nsString   &aNodeValue);

  /**
   * Given a node in the instance data and a string, store the value according
   * to section 10.1.9 of the XForms specification.
   */
  static NS_HIDDEN_(void) SetNodeValue(nsIDOMNode     *aDataNode,
                                       const nsString &aNodeValue);

  /**
   * Convenience method for doing XPath evaluations to get string value
   * for an element.
   * Returns PR_TRUE if the evaluation succeeds.
   */
  static NS_HIDDEN_(PRBool)
    GetSingleNodeBindingValue(nsIDOMElement* aElement, nsString& aValue);

  /**
   * Dispatch an XForms event. 
   */
  static NS_HIDDEN_(nsresult)
    DispatchEvent(nsIDOMNode* aTarget, nsXFormsEvent aEvent);
  
  /**
   * Returns PR_TRUE, if aEvent is an XForms event, and sets the values
   * of aCancelable and aBubbles parameters according to the event type.
   */
  static NS_HIDDEN_(PRBool)
    IsXFormsEvent(const nsAString& aEvent,
                  PRBool& aCancelable,
                  PRBool& aBubbles);

  /**
   * Checks if aEvent is a predefined event and sets the values
   * of aCancelable and aBubbles parameters according to the event type.
   */
  static NS_HIDDEN_(void)
    GetEventDefaults(const nsAString& aEvent,
                     PRBool& aCancelable,
                     PRBool& aBubbles);

  /**
   * Clone the set of IIDs in |aIIDList| into |aOutArray|.
   * |aOutCount| is set to |aIIDCount|.
   */
  static NS_HIDDEN_(nsresult) CloneScriptingInterfaces(const nsIID *aIIDList,
                                                       unsigned int aIIDCount,
                                                       PRUint32 *aOutCount,
                                                       nsIID ***aOutArray);

  /**
   * Returns the context for the element, if set by a parent node.
   *
   * Controls inheriting from nsIXFormsContextControl sets the context for its children.
   *
   * @param aElement          The document element of the caller
   * @param aModel            The model for |aElement| (if (!*aModel), it is set)
   * @param aContextNode      The resulting context node
   * @param aContextPosition  The resulting context position
   * @param aContextSize      The resulting context size
   */
  static NS_HIDDEN_(nsresult) FindParentContext(nsIDOMElement  *aElement,
                                                nsIDOMNode    **aModel,
                                                nsIDOMElement **aContextNode,
                                                PRInt32        *aContextPosition,
                                                PRInt32        *aContextSize);

  /**
   * @return true if aTestURI has the same origin as aBaseURI
   */
  static NS_HIDDEN_(PRBool) CheckSameOrigin(nsIURI *aBaseURI,
                                            nsIURI *aTestURI);

  /**
   * @return true if aNode is element, its namespace URI is 
   * "http://www.w3.org/2002/xforms" and its name is aName.
   */
  static NS_HIDDEN_(PRBool) IsXFormsElement(nsIDOMNode* aNode, 
                                            const nsAString& aName);
};

#endif