/*************************************************************************
 *
 *  File Name (AccessibleHyperlink.idl)
 *
 *  IAccessible2 IDL Specification
 *
 *  Copyright (c) 2007, 2010 Linux Foundation
 *  Copyright (c) 2006 IBM Corporation
 *  Copyright (c) 2000, 2006 Sun Microsystems, Inc.
 *  All rights reserved.
 *
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
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 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *   2. Redistributions in binary form must reproduce the above
 *      copyright notice, this list of conditions and the following
 *      disclaimer in the documentation and/or other materials
 *      provided with the distribution.
 *
 *   3. Neither the name of the Linux Foundation nor the names of its
 *      contributors may be used to endorse or promote products
 *      derived from this software without specific prior written
 *      permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
 *  CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 *  INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 *  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
 *  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 *  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 *  OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 *  EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *  This BSD License conforms to the Open Source Initiative "Simplified
 *  BSD License" as published at:
 *  http://www.opensource.org/licenses/bsd-license.php
 *
 *  IAccessible2 is a trademark of the Linux Foundation. The IAccessible2
 *  mark may be used in accordance with the Linux Foundation Trademark
 *  Policy to indicate compliance with the IAccessible2 specification.
 *
 ************************************************************************/

import "objidl.idl";
import "oaidl.idl";
import "oleacc.idl";
import "AccessibleAction.idl";

/** @brief This interface represents hyperlinks.

 This interface represents a hyperlink associated with a single substring
  of text or single non-text object.  Non-text objects can have either a
  single link or a collection of links such as when the non-text object is
  an image map.

 Linked objects and anchors are implementation dependent. This interface is derived
  from IAccessibleAction.  IAccessibleAction::nActions is one greater than the
  maximum value for the indices used with the methods of this interface.

 Furthermore, the object that implements this interface has to be connected
  implicitly or explicitly with an object that implements IAccessibleText.
  IAccessibleHyperlink::startIndex and IAccessibleHyperlink::endIndex are
  indices with respect to the text exposed by IAccessibleText.

 This interface provides access to a single object which can have multiple actions.
  An example is an image map which is an image with multiple links each of which is
  associated with a separate non-overlapping area of the image.  This interface could
  also be applied to other kinds of objects with multiple actions such as "smart tags"
  which are objects, typically strings, which have multiple actions such as
  "Activate URI", "Bookmark URI", etc.

 An interesting use case is an image map where each area is associated with multiple
  actions, e.g. an image map of smart tags.  In this case you would have to implement
  two levels of accessible hyperlinks.  The first level hyperlinks would only implement
  anchor and anchorTarget.  The anchors would all reference the image object.  The
  anchorTargets would reference the second level accessible hyperlink objects.  None
  of the IAccessibleAction methods would be implemented on the first level hyperlink
  objects.  The second level hyperlink objects would implement the IAccessibleAction
  methods.  Their anchors would also reference the image object and their anchorTargets
  would reference URLs or the objects that would be activated.

 This use case demonstrates that in some cases there is no need for IAccessibleHyperlink
  to derive from IAccessibleAction.  As a result it may be removed in a later version of
  the IDL and it is suggested that implementations should not rely on the inheritance.

*/
[object, uuid(01C20F2B-3DD2-400f-949F-AD00BDAB1D41)]
interface IAccessibleHyperlink : IAccessibleAction
{

  /** @brief Returns an object that represents the link anchor, as appropriate
   for the link at the specified index.
   @param [in] index
    A 0 based index identifies the anchor when, as in the case of an image map,
    there is more than one link represented by this object.  The valid maximal
    index is indicated by IAccessibleAction::nActions.
   @param [out] anchor
    This is an implementation dependent value.  For example, for a text link this
    method could return the substring of the containing string where the substring
    is overridden with link behavior, and for an image link this method could return
    an IUnknown VARIANT for IAccessibleImage.  See the section about
    @ref _variants "VARIANTs" for additional information.
   @retval S_OK
   @retval E_INVALIDARG if bad [in] passed
  */
  [propget] HRESULT anchor
    (
     [in] long index,
     [out, retval] VARIANT *anchor
    );

  /** @brief Returns an object representing the target of the link, as appropriate
   for the link at the specified index.
   @param [in] index
    A 0 based index identifies the anchor when, as in the case of an image map,
    there is more than one link represented by this object.  The valid maximal
    index is indicated by IAccessibleAction::nActions.
   @param [out] anchorTarget
    This is an implementation dependent value.  For example this method could
    return a BSTR VARIANT of the URI.  Alternatively this method could return an
    IUnknown VARIANT of a COM interface representing a target object to be
    activated when the link is activated.  See the section about
    @ref _variants "VARIANTs" for additional information.
   @retval S_OK
   @retval E_INVALIDARG if bad [in] passed
  */
  [propget] HRESULT anchorTarget
    (
     [in] long index,
     [out, retval] VARIANT *anchorTarget
    );

  /** @brief Returns the 0 based character offset at which the textual representation of the hyperlink starts.

   The returned value is related to the IAccessibleText interface of the object that
   owns this hyperlink.
   @param [out] index
   @retval S_OK
  */
  [propget] HRESULT startIndex
    (
     [out, retval] long *index
    );

  /** @brief Returns the 0 based character offset at which the textual representation of the hyperlink ends.

   The returned value is related to the IAccessibleText interface of the object that
   owns this hyperlink. The character at the index is not part of the hypertext.
   @param [out] index
   @retval S_OK
  */
  [propget] HRESULT endIndex
    (
     [out, retval] long *index
    );

  /** @brief Returns whether the target object referenced by this link is still valid.

   This is a volatile state that may change without sending an appropriate event.
   Returns TRUE if the referenced target is still valid and FALSE otherwise.

   This has also been used to indicate whether or not the URI of the anchorTarget
   is malformed.

   @param [out] valid
    If false, one or more of the object's links are invalid.
    If true, all of the object's links are valid.
   @retval S_OK
   @retval S_FALSE if there is nothing to return, [out] value is FALSE
   @note This method is not being used, is deprecated, and should not be implemented or
    used.  It is likely that this method will be removed in a later version of the IDL.
  */
  [propget] HRESULT valid
    (
     [out, retval] boolean *valid
    );
}
