michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim: set ts=2 et sw=2 tw=80: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "nsISupports.idl"
michael@0: 
michael@0: typedef short TextBoundaryType;
michael@0: typedef short PivotMoveReason;
michael@0: 
michael@0: interface nsIAccessible;
michael@0: interface nsIAccessibleText;
michael@0: interface nsIAccessibleTraversalRule;
michael@0: interface nsIAccessiblePivotObserver;
michael@0: 
michael@0: /**
michael@0:  * The pivot interface encapsulates a reference to a single place in an accessible
michael@0:  * subtree. The pivot is a point or a range in the accessible tree. This interface
michael@0:  * provides traversal methods to move the pivot to next/prev state that complies 
michael@0:  * to a given rule.
michael@0:  */
michael@0: [scriptable, uuid(c2938033-e240-4fe5-9cb6-e7ad649ccd10)]
michael@0: interface nsIAccessiblePivot : nsISupports
michael@0: {
michael@0:   const TextBoundaryType CHAR_BOUNDARY = 0;
michael@0:   const TextBoundaryType WORD_BOUNDARY = 1;
michael@0:   const TextBoundaryType LINE_BOUNDARY = 2;
michael@0:   const TextBoundaryType ATTRIBUTE_RANGE_BOUNDARY = 3;
michael@0: 
michael@0:   const PivotMoveReason REASON_NONE = 0;
michael@0:   const PivotMoveReason REASON_NEXT = 1;
michael@0:   const PivotMoveReason REASON_PREV = 2;
michael@0:   const PivotMoveReason REASON_FIRST = 3;
michael@0:   const PivotMoveReason REASON_LAST = 4;
michael@0:   const PivotMoveReason REASON_TEXT = 5;
michael@0:   const PivotMoveReason REASON_POINT = 6;
michael@0: 
michael@0:   /**
michael@0:    * The accessible the pivot is currently pointed at.
michael@0:    */
michael@0:   attribute nsIAccessible position;
michael@0: 
michael@0:   /**
michael@0:    * The root of the subtree in which the pivot traverses.
michael@0:    */
michael@0:   readonly attribute nsIAccessible root;
michael@0: 
michael@0:   /**
michael@0:    * The temporary modal root to which traversal is limited to.
michael@0:    */
michael@0:   attribute nsIAccessible modalRoot;
michael@0: 
michael@0:   /**
michael@0:    * The start offset of the text range the pivot points at, otherwise -1.
michael@0:    */
michael@0:   readonly attribute long startOffset;
michael@0: 
michael@0:   /**
michael@0:    * The end offset of the text range the pivot points at, otherwise -1.
michael@0:    */
michael@0:   readonly attribute long endOffset;
michael@0: 
michael@0:   /**
michael@0:    * Set the pivot's text range in a text accessible.
michael@0:    *
michael@0:    * @param aTextAccessible [in] the text accessible that contains the desired
michael@0:    *                        range.
michael@0:    * @param aStartOffset    [in] the start offset to set.
michael@0:    * @param aEndOffset      [in] the end offset to set.
michael@0:    * @throws NS_ERROR_INVALID_ARG when the offset exceeds the accessible's
michael@0:    *   character count.
michael@0:    */
michael@0:   void setTextRange(in nsIAccessibleText aTextAccessible,
michael@0:                     in long aStartOffset, in long aEndOffset);
michael@0: 
michael@0:   /**
michael@0:    * Move pivot to next object, from current position or given anchor,
michael@0:    * complying to given traversal rule.
michael@0:    *
michael@0:    * @param aRule         [in] traversal rule to use.
michael@0:    * @param aAnchor       [in] accessible to start search from, if not provided,
michael@0:    *                           current position will be used.
michael@0:    * @param aIncludeStart [in] include anchor accessible in search.
michael@0:    * @return true on success, false if there are no new nodes to traverse to.
michael@0:    */
michael@0:   [optional_argc] boolean moveNext(in nsIAccessibleTraversalRule aRule,
michael@0:                                    [optional] in nsIAccessible aAnchor,
michael@0:                                    [optional] in boolean aIncludeStart);
michael@0: 
michael@0:   /**
michael@0:    * Move pivot to previous object, from current position or given anchor,
michael@0:    * complying to given traversal rule.
michael@0:    *
michael@0:    * @param aRule         [in] traversal rule to use.
michael@0:    * @param aAnchor       [in] accessible to start search from, if not provided,
michael@0:    *                           current position will be used.
michael@0:    * @param aIncludeStart [in] include anchor accessible in search.
michael@0:    * @return true on success, false if there are no new nodes to traverse to.
michael@0:    */
michael@0:   [optional_argc] boolean movePrevious(in nsIAccessibleTraversalRule aRule,
michael@0:                                        [optional] in nsIAccessible aAnchor,
michael@0:                                        [optional] in boolean aIncludeStart);
michael@0: 
michael@0:   /**
michael@0:    * Move pivot to first object in subtree complying to given traversal rule.
michael@0:    *
michael@0:    * @param aRule [in] traversal rule to use.
michael@0:    * @return true on success, false if there are no new nodes to traverse to.
michael@0:    */
michael@0:   boolean moveFirst(in nsIAccessibleTraversalRule aRule);
michael@0: 
michael@0:   /**
michael@0:    * Move pivot to last object in subtree complying to given traversal rule.
michael@0:    *
michael@0:    * @param aRule [in] traversal rule to use.
michael@0:    * @return true on success, false if there are no new nodes to traverse to.
michael@0:    */
michael@0:   boolean moveLast(in nsIAccessibleTraversalRule aRule);
michael@0: 
michael@0:   /**
michael@0:    * Move pivot to next text range.
michael@0:    *
michael@0:    * @param aBoundary [in] type of boundary for next text range, character, word,
michael@0:    *                  etc.
michael@0:    * @return true on success, false if there are is no more text.
michael@0:    */
michael@0:   boolean moveNextByText(in TextBoundaryType aBoundary);
michael@0:   
michael@0:   /**
michael@0:    * Move pivot to previous text range.
michael@0:    *
michael@0:    * @param aBoundary [in] type of boundary for previous text range, character,
michael@0:    *                  word, etc.
michael@0:    * @return true on success, false if there are is no more text.
michael@0:    */
michael@0:   boolean movePreviousByText(in TextBoundaryType aBoundary);
michael@0: 
michael@0:   /**
michael@0:    * Move pivot to given coordinate in screen pixels.
michael@0:    *
michael@0:    * @param aRule          [in]  raversal rule to use.
michael@0:    * @param aX             [in]  screen's x coordinate
michael@0:    * @param aY             [in]  screen's y coordinate
michael@0:    * @param aIgnoreNoMatch [in]  don't unset position if no object was found at
michael@0:    *                       point.
michael@0:    * @return true on success, false if the pivot has not been moved.
michael@0:    */
michael@0:   boolean moveToPoint(in nsIAccessibleTraversalRule aRule,
michael@0:                       in long aX, in long aY,
michael@0:                       in boolean aIgnoreNoMatch);
michael@0: 
michael@0:   /**
michael@0:    * Add an observer for pivot changes.
michael@0:    *
michael@0:    * @param aObserver [in] the observer object to be notified of pivot changes.
michael@0:    */
michael@0:   void addObserver(in nsIAccessiblePivotObserver aObserver);
michael@0: 
michael@0:   /**
michael@0:    * Remove an observer for pivot changes.
michael@0:    *
michael@0:    * @param aObserver [in] the observer object to remove from being notified.
michael@0:    */
michael@0:   void removeObserver(in nsIAccessiblePivotObserver aObserver);
michael@0: };
michael@0: 
michael@0: /**
michael@0:  * An observer interface for pivot changes.
michael@0:  */
michael@0: [scriptable, uuid(b6508c5e-c081-467d-835c-613eedf9ee9b)]
michael@0: interface nsIAccessiblePivotObserver : nsISupports
michael@0: {
michael@0:   /**
michael@0:    * Called when the pivot changes.
michael@0:    *
michael@0:    * @param aPivot         [in] the pivot that has changed.
michael@0:    * @param aOldAccessible [in] the old pivot position before the change, or null.
michael@0:    * @param aOldStart      [in] the old start offset, or -1.
michael@0:    * @param aOldEnd        [in] the old end offset, or -1.
michael@0:    * @param aReason        [in] the reason for the pivot change.
michael@0:    */
michael@0:   void onPivotChanged(in nsIAccessiblePivot aPivot,
michael@0:                       in nsIAccessible aOldAccessible,
michael@0:                       in long aOldStart, in long aOldEnd,
michael@0:                       in PivotMoveReason aReason);
michael@0: };
michael@0: 
michael@0: [scriptable, uuid(4d9c4352-20f5-4c54-9580-0c77bb6b1115)]
michael@0: interface nsIAccessibleTraversalRule : nsISupports
michael@0: {
michael@0:   /* Ignore this accessible object */
michael@0:   const unsigned short FILTER_IGNORE = 0x0;
michael@0:   /* Accept this accessible object */
michael@0:   const unsigned short FILTER_MATCH = 0x1;
michael@0:   /* Don't traverse accessibles children */
michael@0:   const unsigned short FILTER_IGNORE_SUBTREE = 0x2;
michael@0: 
michael@0:   /* Pre-filters */
michael@0:   const unsigned long PREFILTER_INVISIBLE     = 0x00000001;
michael@0:   const unsigned long PREFILTER_OFFSCREEN     = 0x00000002;
michael@0:   const unsigned long PREFILTER_NOT_FOCUSABLE = 0x00000004;
michael@0:   const unsigned long PREFILTER_ARIA_HIDDEN   = 0x00000008;
michael@0:   const unsigned long PREFILTER_TRANSPARENT   = 0x00000010;
michael@0: 
michael@0:   /**
michael@0:    * Pre-filter bitfield to filter out obviously ignorable nodes and lighten
michael@0:    * the load on match().
michael@0:    */
michael@0:   readonly attribute unsigned long preFilter;
michael@0: 
michael@0:   /**
michael@0:    * Retrieve a list of roles that the traversal rule should test for. Any node
michael@0:    * with a role not in this list will automatically be ignored. An empty list
michael@0:    * will match all roles. It should be assumed that this method is called once
michael@0:    * at the start of a traversal, so changing the method's return result after
michael@0:    * that would have no affect.
michael@0:    *
michael@0:    * @param aRoles [out] an array of the roles to match.
michael@0:    * @param aCount [out] the length of the array.
michael@0:    */
michael@0:   void getMatchRoles([array, size_is(aCount)]out unsigned long aRoles,
michael@0:                      [retval]out unsigned long aCount);
michael@0: 
michael@0:   /**
michael@0:    * Determines if a given accessible is to be accepted in our traversal rule
michael@0:    *
michael@0:    * @param aAccessible [in] accessible to examine.
michael@0:    * @return a bitfield of FILTER_MATCH and FILTER_IGNORE_SUBTREE.
michael@0:    */
michael@0:   unsigned short match(in nsIAccessible aAccessible);
michael@0: };