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	/*
	* Copyright (c) 2003, 2006, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package sun.font;

	/* remember that the API requires a Font use a
	* consistent glyph id. for a code point, and this is a
	* problem if a particular strike uses native scaler sometimes
	* and T2K others. That needs to be dealt with somewhere, but
	* here we can just always get the same glyph code without
	* needing a strike.
	*
	* The C implementation would cache the results of anything up
	* to the maximum surrogate pair code point.
	* This implementation will not cache as much, since the storage
	* requirements are not justifiable. Even so it still can use up
	* to 2162564 bytes of storage per composite font. If an app
	* calls canDisplay on this range for all 20 composite fonts that's
	* over 1Mb of cached data. May need to employ WeakReferences if
	* this appears to cause problems.
	*/

	public class CompositeGlyphMapper extends CharToGlyphMapper {

	public static final int SLOTMASK = 0xff000000;
	public static final int GLYPHMASK = 0x00ffffff;

	public static final int NBLOCKS = 216;
	public static final int BLOCKSZ = 256;
	public static final int MAXUNICODE = NBLOCKS*BLOCKSZ;


	CompositeFont font;
	CharToGlyphMapper slotMappers[];
	int[][] glyphMaps;
	private boolean hasExcludes;

	public CompositeGlyphMapper(CompositeFont compFont) {
	font = compFont;
	initMapper();
	/* This is often false which saves the overhead of a
	* per-mapped char method call.
	*/
	hasExcludes = compFont.exclusionRanges != null &&
	compFont.maxIndices != null;
	}

	public final int compositeGlyphCode(int slot, int glyphCode) {
	return (slot << 24 \| (glyphCode & GLYPHMASK));
	}

	private final void initMapper() {
	if (missingGlyph == CharToGlyphMapper.UNINITIALIZED_GLYPH) {
	if (glyphMaps == null) {
	glyphMaps = new int[NBLOCKS][];
	}
	slotMappers = new CharToGlyphMapper[font.numSlots];
	/* This requires that slot 0 is never empty. */
	missingGlyph = font.getSlotFont(0).getMissingGlyphCode();
	missingGlyph = compositeGlyphCode(0, missingGlyph);
	}
	}

	private int getCachedGlyphCode(int unicode) {
	if (unicode >= MAXUNICODE) {
	return UNINITIALIZED_GLYPH; // don't cache surrogates
	}
	int[] gmap;
	if ((gmap = glyphMaps[unicode >> 8]) == null) {
	return UNINITIALIZED_GLYPH;
	}
	return gmap[unicode & 0xff];
	}

	private void setCachedGlyphCode(int unicode, int glyphCode) {
	if (unicode >= MAXUNICODE) {
	return; // don't cache surrogates
	}
	int index0 = unicode >> 8;
	if (glyphMaps[index0] == null) {
	glyphMaps[index0] = new int[BLOCKSZ];
	for (int i=0;i<BLOCKSZ;i++) {
	glyphMaps[index0][i] = UNINITIALIZED_GLYPH;
	}
	}
	glyphMaps[index0][unicode & 0xff] = glyphCode;
	}

	private final CharToGlyphMapper getSlotMapper(int slot) {
	CharToGlyphMapper mapper = slotMappers[slot];
	if (mapper == null) {
	mapper = font.getSlotFont(slot).getMapper();
	slotMappers[slot] = mapper;
	}
	return mapper;
	}

	private final int convertToGlyph(int unicode) {

	for (int slot = 0; slot < font.numSlots; slot++) {
	if (!hasExcludes \|\| !font.isExcludedChar(slot, unicode)) {
	CharToGlyphMapper mapper = getSlotMapper(slot);
	int glyphCode = mapper.charToGlyph(unicode);
	if (glyphCode != mapper.getMissingGlyphCode()) {
	glyphCode = compositeGlyphCode(slot, glyphCode);
	setCachedGlyphCode(unicode, glyphCode);
	return glyphCode;
	}
	}
	}
	return missingGlyph;
	}

	public int getNumGlyphs() {
	int numGlyphs = 0;
	/* The number of glyphs in a composite is affected by
	* exclusion ranges and duplicates (ie the same code point is
	* mapped by two different fonts) and also whether or not to
	* count fallback fonts. A nearly correct answer would be very
	* expensive to generate. A rough ballpark answer would
	* just count the glyphs in all the slots. However this would
	* initialize mappers for all slots when they aren't necessarily
	* needed. For now just use the first slot as JDK 1.4 did.
	*/
	for (int slot=0; slot<1 /font.numSlots/; slot++) {
	CharToGlyphMapper mapper = slotMappers[slot];
	if (mapper == null) {
	mapper = font.getSlotFont(slot).getMapper();
	slotMappers[slot] = mapper;
	}
	numGlyphs += mapper.getNumGlyphs();
	}
	return numGlyphs;
	}

	public int charToGlyph(int unicode) {

	int glyphCode = getCachedGlyphCode(unicode);
	if (glyphCode == UNINITIALIZED_GLYPH) {
	glyphCode = convertToGlyph(unicode);
	}
	return glyphCode;
	}

	public int charToGlyph(int unicode, int prefSlot) {
	if (prefSlot >= 0) {
	CharToGlyphMapper mapper = getSlotMapper(prefSlot);
	int glyphCode = mapper.charToGlyph(unicode);
	if (glyphCode != mapper.getMissingGlyphCode()) {
	return compositeGlyphCode(prefSlot, glyphCode);
	}
	}
	return charToGlyph(unicode);
	}

	public int charToGlyph(char unicode) {

	int glyphCode = getCachedGlyphCode(unicode);
	if (glyphCode == UNINITIALIZED_GLYPH) {
	glyphCode = convertToGlyph(unicode);
	}
	return glyphCode;
	}

	/* This variant checks if shaping is needed and immediately
	* returns true if it does. A caller of this method should be expecting
	* to check the return type because it needs to know how to handle
	* the character data for display.
	*/
	public boolean charsToGlyphsNS(int count, char[] unicodes, int[] glyphs) {

	for (int i=0; i<count; i++) {
	int code = unicodes[i]; // char is unsigned.

	if (code >= HI_SURROGATE_START &&
	code <= HI_SURROGATE_END && i < count - 1) {
	char low = unicodes[i + 1];

	if (low >= LO_SURROGATE_START &&
	low <= LO_SURROGATE_END) {
	code = (code - HI_SURROGATE_START) *
	0x400 + low - LO_SURROGATE_START + 0x10000;
	glyphs[i + 1] = INVISIBLE_GLYPH_ID;
	}
	}

	int gc = glyphs[i] = getCachedGlyphCode(code);
	if (gc == UNINITIALIZED_GLYPH) {
	glyphs[i] = convertToGlyph(code);
	}

	if (code < FontUtilities.MIN_LAYOUT_CHARCODE) {
	continue;
	}
	else if (FontUtilities.isComplexCharCode(code)) {
	return true;
	}
	else if (code >= 0x10000) {
	i += 1; // Empty glyph slot after surrogate
	continue;
	}
	}

	return false;
	}

	/* The conversion is not very efficient - looping as it does, converting
	* one char at a time. However the cache should fill very rapidly.
	*/
	public void charsToGlyphs(int count, char[] unicodes, int[] glyphs) {
	for (int i=0; i<count; i++) {
	int code = unicodes[i]; // char is unsigned.

	if (code >= HI_SURROGATE_START &&
	code <= HI_SURROGATE_END && i < count - 1) {
	char low = unicodes[i + 1];

	if (low >= LO_SURROGATE_START &&
	low <= LO_SURROGATE_END) {
	code = (code - HI_SURROGATE_START) *
	0x400 + low - LO_SURROGATE_START + 0x10000;

	int gc = glyphs[i] = getCachedGlyphCode(code);
	if (gc == UNINITIALIZED_GLYPH) {
	glyphs[i] = convertToGlyph(code);
	}
	i += 1; // Empty glyph slot after surrogate
	glyphs[i] = INVISIBLE_GLYPH_ID;
	continue;
	}
	}

	int gc = glyphs[i] = getCachedGlyphCode(code);
	if (gc == UNINITIALIZED_GLYPH) {
	glyphs[i] = convertToGlyph(code);
	}
	}
	}

	public void charsToGlyphs(int count, int[] unicodes, int[] glyphs) {
	for (int i=0; i<count; i++) {
	int code = unicodes[i];

	glyphs[i] = getCachedGlyphCode(code);
	if (glyphs[i] == UNINITIALIZED_GLYPH) {
	glyphs[i] = convertToGlyph(code);
	}
	}
	}

	}

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