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	/*
	* Copyright (c) 1996, 2019, 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
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	/*
	* (C) Copyright Taligent, Inc. 1996, 1997 - All Rights Reserved
	* (C) Copyright IBM Corp. 1996 - 1998 - All Rights Reserved
	*
	* The original version of this source code and documentation is copyrighted
	* and owned by Taligent, Inc., a wholly-owned subsidiary of IBM. These
	* materials are provided under terms of a License Agreement between Taligent
	* and Sun. This technology is protected by multiple US and International
	* patents. This notice and attribution to Taligent may not be removed.
	* Taligent is a registered trademark of Taligent, Inc.
	*
	*/

	package java.text;

	import java.io.InvalidObjectException;
	import java.io.IOException;
	import java.io.ObjectInputStream;
	import java.util.Arrays;

	/**
	* A {@code ChoiceFormat} allows you to attach a format to a range of numbers.
	* It is generally used in a {@code MessageFormat} for handling plurals.
	* The choice is specified with an ascending list of doubles, where each item
	* specifies a half-open interval up to the next item:
	* <blockquote>
	* <pre>
	* X matches j if and only if limit[j] ≤ X < limit[j+1]
	* </pre>
	* </blockquote>
	* If there is no match, then either the first or last index is used, depending
	* on whether the number (X) is too low or too high. If the limit array is not
	* in ascending order, the results of formatting will be incorrect. ChoiceFormat
	* also accepts <code>\u221E</code> as equivalent to infinity(INF).
	*
	* <p>
	* <strong>Note:</strong>
	* {@code ChoiceFormat} differs from the other {@code Format}
	* classes in that you create a {@code ChoiceFormat} object with a
	* constructor (not with a {@code getInstance} style factory
	* method). The factory methods aren't necessary because {@code ChoiceFormat}
	* doesn't require any complex setup for a given locale. In fact,
	* {@code ChoiceFormat} doesn't implement any locale specific behavior.
	*
	* <p>
	* When creating a {@code ChoiceFormat}, you must specify an array of formats
	* and an array of limits. The length of these arrays must be the same.
	* For example,
	* <ul>
	* <li>
	* <em>limits</em> = {1,2,3,4,5,6,7}<br>
	* <em>formats</em> = {"Sun","Mon","Tue","Wed","Thur","Fri","Sat"}
	* <li>
	* <em>limits</em> = {0, 1, ChoiceFormat.nextDouble(1)}<br>
	* <em>formats</em> = {"no files", "one file", "many files"}<br>
	* ({@code nextDouble} can be used to get the next higher double, to
	* make the half-open interval.)
	* </ul>
	*
	* <p>
	* Here is a simple example that shows formatting and parsing:
	* <blockquote>
	* <pre>{@code
	* double[] limits = {1,2,3,4,5,6,7};
	* String[] dayOfWeekNames = {"Sun","Mon","Tue","Wed","Thur","Fri","Sat"};
	* ChoiceFormat form = new ChoiceFormat(limits, dayOfWeekNames);
	* ParsePosition status = new ParsePosition(0);
	* for (double i = 0.0; i <= 8.0; ++i) {
	* status.setIndex(0);
	* System.out.println(i + " -> " + form.format(i) + " -> "
	* + form.parse(form.format(i),status));
	* }
	* }</pre>
	* </blockquote>
	* Here is a more complex example, with a pattern format:
	* <blockquote>
	* <pre>{@code
	* double[] filelimits = {0,1,2};
	* String[] filepart = {"are no files","is one file","are {2} files"};
	* ChoiceFormat fileform = new ChoiceFormat(filelimits, filepart);
	* Format[] testFormats = {fileform, null, NumberFormat.getInstance()};
	* MessageFormat pattform = new MessageFormat("There {0} on {1}");
	* pattform.setFormats(testFormats);
	* Object[] testArgs = {null, "ADisk", null};
	* for (int i = 0; i < 4; ++i) {
	* testArgs[0] = new Integer(i);
	* testArgs[2] = testArgs[0];
	* System.out.println(pattform.format(testArgs));
	* }
	* }</pre>
	* </blockquote>
	* <p>
	* Specifying a pattern for ChoiceFormat objects is fairly straightforward.
	* For example:
	* <blockquote>
	* <pre>{@code
	* ChoiceFormat fmt = new ChoiceFormat(
	* "-1#is negative\| 0#is zero or fraction \| 1#is one \|1.0<is 1+ \|2#is two \|2<is more than 2.");
	* System.out.println("Formatter Pattern : " + fmt.toPattern());
	*
	* System.out.println("Format with -INF : " + fmt.format(Double.NEGATIVE_INFINITY));
	* System.out.println("Format with -1.0 : " + fmt.format(-1.0));
	* System.out.println("Format with 0 : " + fmt.format(0));
	* System.out.println("Format with 0.9 : " + fmt.format(0.9));
	* System.out.println("Format with 1.0 : " + fmt.format(1));
	* System.out.println("Format with 1.5 : " + fmt.format(1.5));
	* System.out.println("Format with 2 : " + fmt.format(2));
	* System.out.println("Format with 2.1 : " + fmt.format(2.1));
	* System.out.println("Format with NaN : " + fmt.format(Double.NaN));
	* System.out.println("Format with +INF : " + fmt.format(Double.POSITIVE_INFINITY));
	* }</pre>
	* </blockquote>
	* And the output result would be like the following:
	* <blockquote>
	* <pre>{@code
	* Format with -INF : is negative
	* Format with -1.0 : is negative
	* Format with 0 : is zero or fraction
	* Format with 0.9 : is zero or fraction
	* Format with 1.0 : is one
	* Format with 1.5 : is 1+
	* Format with 2 : is two
	* Format with 2.1 : is more than 2.
	* Format with NaN : is negative
	* Format with +INF : is more than 2.
	* }</pre>
	* </blockquote>
	*
	* <h2><a id="synchronization">Synchronization</a></h2>
	*
	* <p>
	* Choice formats are not synchronized.
	* It is recommended to create separate format instances for each thread.
	* If multiple threads access a format concurrently, it must be synchronized
	* externally.
	*
	*
	* @see DecimalFormat
	* @see MessageFormat
	* @author Mark Davis
	* @since 1.1
	*/
	public class ChoiceFormat extends NumberFormat {

	// Proclaim serial compatibility with 1.1 FCS
	@java.io.Serial
	private static final long serialVersionUID = 1795184449645032964L;

	/**
	* Sets the pattern.
	* @param newPattern See the class description.
	* @throws NullPointerException if {@code newPattern}
	* is {@code null}
	*/
	public void applyPattern(String newPattern) {
	StringBuffer[] segments = new StringBuffer[2];
	for (int i = 0; i < segments.length; ++i) {
	segments[i] = new StringBuffer();
	}
	double[] newChoiceLimits = new double[30];
	String[] newChoiceFormats = new String[30];
	int count = 0;
	int part = 0;
	double startValue = 0;
	double oldStartValue = Double.NaN;
	boolean inQuote = false;
	for (int i = 0; i < newPattern.length(); ++i) {
	char ch = newPattern.charAt(i);
	if (ch=='\'') {
	// Check for "''" indicating a literal quote
	if ((i+1)<newPattern.length() && newPattern.charAt(i+1)==ch) {
	segments[part].append(ch);
	++i;
	} else {
	inQuote = !inQuote;
	}
	} else if (inQuote) {
	segments[part].append(ch);
	} else if (ch == '<' \|\| ch == '#' \|\| ch == '\u2264') {
	if (segments[0].length() == 0) {
	throw new IllegalArgumentException("Each interval must"
	+ " contain a number before a format");
	}

	String tempBuffer = segments[0].toString();
	if (tempBuffer.equals("\u221E")) {
	startValue = Double.POSITIVE_INFINITY;
	} else if (tempBuffer.equals("-\u221E")) {
	startValue = Double.NEGATIVE_INFINITY;
	} else {
	startValue = Double.parseDouble(tempBuffer);
	}

	if (ch == '<' && startValue != Double.POSITIVE_INFINITY &&
	startValue != Double.NEGATIVE_INFINITY) {
	startValue = nextDouble(startValue);
	}
	if (startValue <= oldStartValue) {
	throw new IllegalArgumentException("Incorrect order of"
	+ " intervals, must be in ascending order");
	}
	segments[0].setLength(0);
	part = 1;
	} else if (ch == '\|') {
	if (count == newChoiceLimits.length) {
	newChoiceLimits = doubleArraySize(newChoiceLimits);
	newChoiceFormats = doubleArraySize(newChoiceFormats);
	}
	newChoiceLimits[count] = startValue;
	newChoiceFormats[count] = segments[1].toString();
	++count;
	oldStartValue = startValue;
	segments[1].setLength(0);
	part = 0;
	} else {
	segments[part].append(ch);
	}
	}
	// clean up last one
	if (part == 1) {
	if (count == newChoiceLimits.length) {
	newChoiceLimits = doubleArraySize(newChoiceLimits);
	newChoiceFormats = doubleArraySize(newChoiceFormats);
	}
	newChoiceLimits[count] = startValue;
	newChoiceFormats[count] = segments[1].toString();
	++count;
	}
	choiceLimits = new double[count];
	System.arraycopy(newChoiceLimits, 0, choiceLimits, 0, count);
	choiceFormats = new String[count];
	System.arraycopy(newChoiceFormats, 0, choiceFormats, 0, count);
	}

	/**
	* Gets the pattern.
	*
	* @return the pattern string
	*/
	public String toPattern() {
	StringBuilder result = new StringBuilder();
	for (int i = 0; i < choiceLimits.length; ++i) {
	if (i != 0) {
	result.append('\|');
	}
	// choose based upon which has less precision
	// approximate that by choosing the closest one to an integer.
	// could do better, but it's not worth it.
	double less = previousDouble(choiceLimits[i]);
	double tryLessOrEqual = Math.abs(Math.IEEEremainder(choiceLimits[i], 1.0d));
	double tryLess = Math.abs(Math.IEEEremainder(less, 1.0d));

	if (tryLessOrEqual < tryLess) {
	result.append(choiceLimits[i]);
	result.append('#');
	} else {
	if (choiceLimits[i] == Double.POSITIVE_INFINITY) {
	result.append("\u221E");
	} else if (choiceLimits[i] == Double.NEGATIVE_INFINITY) {
	result.append("-\u221E");
	} else {
	result.append(less);
	}
	result.append('<');
	}
	// Append choiceFormats[i], using quotes if there are special characters.
	// Single quotes themselves must be escaped in either case.
	String text = choiceFormats[i];
	boolean needQuote = text.indexOf('<') >= 0
	\|\| text.indexOf('#') >= 0
	\|\| text.indexOf('\u2264') >= 0
	\|\| text.indexOf('\|') >= 0;
	if (needQuote) result.append('\'');
	if (text.indexOf('\'') < 0) result.append(text);
	else {
	for (int j=0; j<text.length(); ++j) {
	char c = text.charAt(j);
	result.append(c);
	if (c == '\'') result.append(c);
	}
	}
	if (needQuote) result.append('\'');
	}
	return result.toString();
	}

	/**
	* Constructs with limits and corresponding formats based on the pattern.
	*
	* @param newPattern the new pattern string
	* @throws NullPointerException if {@code newPattern} is
	* {@code null}
	* @see #applyPattern
	*/
	public ChoiceFormat(String newPattern) {
	applyPattern(newPattern);
	}

	/**
	* Constructs with the limits and the corresponding formats.
	*
	* @param limits limits in ascending order
	* @param formats corresponding format strings
	* @throws NullPointerException if {@code limits} or {@code formats}
	* is {@code null}
	* @see #setChoices
	*/
	public ChoiceFormat(double[] limits, String[] formats) {
	setChoices(limits, formats);
	}

	/**
	* Set the choices to be used in formatting.
	* @param limits contains the top value that you want
	* parsed with that format, and should be in ascending sorted order. When
	* formatting X, the choice will be the i, where
	* limit[i] ≤ X {@literal <} limit[i+1].
	* If the limit array is not in ascending order, the results of formatting
	* will be incorrect.
	* @param formats are the formats you want to use for each limit.
	* They can be either Format objects or Strings.
	* When formatting with object Y,
	* if the object is a NumberFormat, then ((NumberFormat) Y).format(X)
	* is called. Otherwise Y.toString() is called.
	* @throws NullPointerException if {@code limits} or
	* {@code formats} is {@code null}
	*/
	public void setChoices(double[] limits, String formats[]) {
	if (limits.length != formats.length) {
	throw new IllegalArgumentException(
	"Array and limit arrays must be of the same length.");
	}
	choiceLimits = Arrays.copyOf(limits, limits.length);
	choiceFormats = Arrays.copyOf(formats, formats.length);
	}

	/**
	* Get the limits passed in the constructor.
	* @return the limits.
	*/
	public double[] getLimits() {
	double[] newLimits = Arrays.copyOf(choiceLimits, choiceLimits.length);
	return newLimits;
	}

	/**
	* Get the formats passed in the constructor.
	* @return the formats.
	*/
	public Object[] getFormats() {
	Object[] newFormats = Arrays.copyOf(choiceFormats, choiceFormats.length);
	return newFormats;
	}

	// Overrides

	/**
	* Specialization of format. This method really calls
	* {@code format(double, StringBuffer, FieldPosition)}
	* thus the range of longs that are supported is only equal to
	* the range that can be stored by double. This will never be
	* a practical limitation.
	*/
	public StringBuffer format(long number, StringBuffer toAppendTo,
	FieldPosition status) {
	return format((double)number, toAppendTo, status);
	}

	/**
	* Returns pattern with formatted double.
	* @param number number to be formatted and substituted.
	* @param toAppendTo where text is appended.
	* @param status ignore no useful status is returned.
	* @throws NullPointerException if {@code toAppendTo}
	* is {@code null}
	*/
	public StringBuffer format(double number, StringBuffer toAppendTo,
	FieldPosition status) {
	// find the number
	int i;
	for (i = 0; i < choiceLimits.length; ++i) {
	if (!(number >= choiceLimits[i])) {
	// same as number < choiceLimits, except catchs NaN
	break;
	}
	}
	--i;
	if (i < 0) i = 0;
	// return either a formatted number, or a string
	return toAppendTo.append(choiceFormats[i]);
	}

	/**
	* Parses a Number from the input text.
	* @param text the source text.
	* @param status an input-output parameter. On input, the
	* status.index field indicates the first character of the
	* source text that should be parsed. On exit, if no error
	* occurred, status.index is set to the first unparsed character
	* in the source text. On exit, if an error did occur,
	* status.index is unchanged and status.errorIndex is set to the
	* first index of the character that caused the parse to fail.
	* @return A Number representing the value of the number parsed.
	* @throws NullPointerException if {@code status} is {@code null}
	* or if {@code text} is {@code null} and the list of
	* choice strings is not empty.
	*/
	public Number parse(String text, ParsePosition status) {
	// find the best number (defined as the one with the longest parse)
	int start = status.index;
	int furthest = start;
	double bestNumber = Double.NaN;
	double tempNumber = 0.0;
	for (int i = 0; i < choiceFormats.length; ++i) {
	String tempString = choiceFormats[i];
	if (text.regionMatches(start, tempString, 0, tempString.length())) {
	status.index = start + tempString.length();
	tempNumber = choiceLimits[i];
	if (status.index > furthest) {
	furthest = status.index;
	bestNumber = tempNumber;
	if (furthest == text.length()) break;
	}
	}
	}
	status.index = furthest;
	if (status.index == start) {
	status.errorIndex = furthest;
	}
	return Double.valueOf(bestNumber);
	}

	/**
	* Finds the least double greater than {@code d}.
	* If {@code NaN}, returns same value.
	* <p>Used to make half-open intervals.
	*
	* @implNote This is equivalent to calling
	* {@link Math#nextUp(double) Math.nextUp(d)}
	*
	* @param d the reference value
	* @return the least double value greather than {@code d}
	* @see #previousDouble
	*/
	public static final double nextDouble (double d) {
	return Math.nextUp(d);
	}

	/**
	* Finds the greatest double less than {@code d}.
	* If {@code NaN}, returns same value.
	*
	* @implNote This is equivalent to calling
	* {@link Math#nextDown(double) Math.nextDown(d)}
	*
	* @param d the reference value
	* @return the greatest double value less than {@code d}
	* @see #nextDouble
	*/
	public static final double previousDouble (double d) {
	return Math.nextDown(d);
	}

	/**
	* Overrides Cloneable
	*/
	public Object clone()
	{
	ChoiceFormat other = (ChoiceFormat) super.clone();
	// for primitives or immutables, shallow clone is enough
	other.choiceLimits = choiceLimits.clone();
	other.choiceFormats = choiceFormats.clone();
	return other;
	}

	/**
	* Generates a hash code for the message format object.
	*/
	public int hashCode() {
	int result = choiceLimits.length;
	if (choiceFormats.length > 0) {
	// enough for reasonable distribution
	result ^= choiceFormats[choiceFormats.length-1].hashCode();
	}
	return result;
	}

	/**
	* Equality comparison between two
	*/
	public boolean equals(Object obj) {
	if (obj == null) return false;
	if (this == obj) // quick check
	return true;
	if (getClass() != obj.getClass())
	return false;
	ChoiceFormat other = (ChoiceFormat) obj;
	return (Arrays.equals(choiceLimits, other.choiceLimits)
	&& Arrays.equals(choiceFormats, other.choiceFormats));
	}

	/**
	* After reading an object from the input stream, do a simple verification
	* to maintain class invariants.
	* @throws InvalidObjectException if the objects read from the stream is invalid.
	*/
	@java.io.Serial
	private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
	in.defaultReadObject();
	if (choiceLimits.length != choiceFormats.length) {
	throw new InvalidObjectException(
	"limits and format arrays of different length.");
	}
	}

	// ===============privates===========================

	/**
	* A list of lower bounds for the choices. The formatter will return
	* {@code choiceFormats[i]} if the number being formatted is greater than or equal to
	* {@code choiceLimits[i]} and less than {@code choiceLimits[i+1]}.
	* @serial
	*/
	private double[] choiceLimits;

	/**
	* A list of choice strings. The formatter will return
	* {@code choiceFormats[i]} if the number being formatted is greater than or equal to
	* {@code choiceLimits[i]} and less than {@code choiceLimits[i+1]}.
	* @serial
	*/
	private String[] choiceFormats;

	/**
	* Finds the least double greater than {@code d} (if {@code positive} is
	* {@code true}), or the greatest double less than {@code d} (if
	* {@code positive} is {@code false}).
	* If {@code NaN}, returns same value.
	*
	* @implNote This is equivalent to calling
	* {@code positive ? Math.nextUp(d) : Math.nextDown(d)}
	*
	* @param d the reference value
	* @param positive {@code true} if the least double is desired;
	* {@code false} otherwise
	* @return the least or greater double value
	*/
	public static double nextDouble (double d, boolean positive) {
	return positive ? Math.nextUp(d) : Math.nextDown(d);
	}

	private static double[] doubleArraySize(double[] array) {
	int oldSize = array.length;
	double[] newArray = new double[oldSize * 2];
	System.arraycopy(array, 0, newArray, 0, oldSize);
	return newArray;
	}

	private String[] doubleArraySize(String[] array) {
	int oldSize = array.length;
	String[] newArray = new String[oldSize * 2];
	System.arraycopy(array, 0, newArray, 0, oldSize);
	return newArray;
	}

	}

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