sl@0: /*
sl@0:  **********************************************************************
sl@0:  *   Copyright (C) 1998-2004, International Business Machines
sl@0:  *   Corporation and others.  All Rights Reserved.
sl@0:  **********************************************************************
sl@0:  */
sl@0: 
sl@0: #ifndef __LEINSERTIONLIST_H
sl@0: #define __LEINSERTIONLIST_H
sl@0: 
sl@0: #include "LETypes.h"
sl@0: 
sl@0: U_NAMESPACE_BEGIN
sl@0: 
sl@0: struct InsertionRecord;
sl@0: 
sl@0: /**
sl@0:  * This class encapsulates the callback used by <code>LEInsertionList</code>
sl@0:  * to apply an insertion from the insertion list.
sl@0:  *
sl@0:  * @internal
sl@0:  */
sl@0: class LEInsertionCallback
sl@0: {
sl@0: public:
sl@0:     /**
sl@0:      * This method will be called by <code>LEInsertionList::applyInsertions</code> for each
sl@0:      * entry on the insertion list.
sl@0:      *
sl@0:      * @param atPosition the position of the insertion
sl@0:      * @param count the number of glyphs to insert
sl@0:      * @param newGlyphs the address of the glyphs to insert
sl@0:      *
sl@0:      * @return <code>TRUE</code> if <code>LEInsertions::applyInsertions</code> should
sl@0:      *         stop after applying this insertion.
sl@0:      *
sl@0:      * @internal
sl@0:      */
sl@0:     virtual le_bool applyInsertion(le_int32 atPosition, le_int32 count, LEGlyphID newGlyphs[]) = 0;
sl@0: };
sl@0: 
sl@0: /**
sl@0:  * This class is used to keep track of insertions to an array of
sl@0:  * <code>LEGlyphIDs</code>. The insertions are kept on a linked
sl@0:  * list of <code>InsertionRecords</code> so that the glyph array
sl@0:  * doesn't have to be grown for each insertion. The insertions are
sl@0:  * stored on the list from leftmost to rightmost to make it easier
sl@0:  * to do the insertions.
sl@0:  *
sl@0:  * The insertions are applied to the array by calling the
sl@0:  * <code>applyInsertions</code> method, which calls a client
sl@0:  * supplied <code>LEInsertionCallback</code> object to actually
sl@0:  * apply the individual insertions.
sl@0:  *
sl@0:  * @internal
sl@0:  */
sl@0: class LEInsertionList : public UObject
sl@0: {
sl@0: public:
sl@0:     /**
sl@0:      * Construct an empty insertion list.
sl@0:      *
sl@0:      * @param rightToLeft <code>TRUE</code> if the glyphs are stored
sl@0:      *                    in the array in right to left order.
sl@0:      *
sl@0:      * @internal
sl@0:      */
sl@0:     LEInsertionList(le_bool rightToLeft);
sl@0: 
sl@0:     /**
sl@0:      * The destructor.
sl@0:      */
sl@0:     ~LEInsertionList();
sl@0: 
sl@0:     /**
sl@0:      * Add an entry to the insertion list.
sl@0:      *
sl@0:      * @param position the glyph at this position in the array will be
sl@0:      *                 replaced by the new glyphs.
sl@0:      * @param count the number of new glyphs
sl@0:      * @param success set to an error code if the auxillary data cannot be retrieved.
sl@0:      *
sl@0:      * @return the address of an array in which to store the new glyphs. This will
sl@0:      *         <em>not</em> be in the glyph array.
sl@0:      *
sl@0:      * @internal
sl@0:      */
sl@0:     LEGlyphID *insert(le_int32 position, le_int32 count,
sl@0:         LEErrorCode &success);
sl@0: 
sl@0:     /**
sl@0:      * Return the number of new glyphs that have been inserted.
sl@0:      *
sl@0:      * @return the number of new glyphs which have been inserted
sl@0:      *
sl@0:      * @internal
sl@0:      */
sl@0:     le_int32 getGrowAmount();
sl@0: 
sl@0:     /**
sl@0:      * Call the <code>LEInsertionCallback</code> once for each
sl@0:      * entry on the insertion list.
sl@0:      *
sl@0:      * @param callback the <code>LEInsertionCallback</code> to call for each insertion.
sl@0:      *
sl@0:      * @return <code>TRUE</code> if <code>callback</code> returned <code>TRUE</code> to
sl@0:      *         terminate the insertion list processing.
sl@0:      *
sl@0:      * @internal
sl@0:      */
sl@0:     le_bool applyInsertions(LEInsertionCallback *callback);
sl@0: 
sl@0:     /**
sl@0:      * Empty the insertion list and free all associated
sl@0:      * storage.
sl@0:      *
sl@0:      * @internal
sl@0:      */
sl@0:     void reset();
sl@0: 
sl@0:     /**
sl@0:      * ICU "poor man's RTTI", returns a UClassID for the actual class.
sl@0:      *
sl@0:      * @stable ICU 2.8
sl@0:      */
sl@0:     virtual UClassID getDynamicClassID() const;
sl@0: 
sl@0:     /**
sl@0:      * ICU "poor man's RTTI", returns a UClassID for this class.
sl@0:      *
sl@0:      * @stable ICU 2.8
sl@0:      */
sl@0:     static UClassID getStaticClassID();
sl@0: 
sl@0: private:
sl@0: 
sl@0:     /**
sl@0:      * The head of the insertion list.
sl@0:      *
sl@0:      * @internal
sl@0:      */
sl@0:     InsertionRecord *head;
sl@0: 
sl@0:     /**
sl@0:      * The tail of the insertion list.
sl@0:      *
sl@0:      * @internal
sl@0:      */
sl@0:     InsertionRecord *tail;
sl@0: 
sl@0:     /**
sl@0:      * The total number of new glyphs on the insertion list.
sl@0:      *
sl@0:      * @internal
sl@0:      */
sl@0:     le_int32 growAmount;
sl@0: 
sl@0:     /**
sl@0:      * Set to <code>TRUE</code> if the glyphs are in right
sl@0:      * to left order. Since we want the rightmost insertion
sl@0:      * to be first on the list, we need to append the
sl@0:      * insertions in this case. Otherwise they're prepended.
sl@0:      *
sl@0:      * @internal
sl@0:      */
sl@0:     le_bool  append;
sl@0: };
sl@0: 
sl@0: U_NAMESPACE_END
sl@0: #endif
sl@0: