/*
 * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 */

/*
 *
 *
 *
 *
 *
 * Copyright (c) 2008-2012, Stephen Colebourne & Michael Nascimento Santos
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * * Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * * 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.
 *
 * * Neither the name of JSR-310 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 OWNER 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.
 */
package java.time.format;

import java.text.DecimalFormatSymbols;
import java.util.Collections;
import java.util.HashSet;
import java.util.Locale;
import java.util.Objects;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;

/**
 * Localized decimal style used in date and time formatting.
 * <p>
 * A significant part of dealing with dates and times is the localization.
 * This class acts as a central point for accessing the information.
 *
 * @implSpec
 * This class is immutable and thread-safe.
 *
 * @since 1.8
 */
public final class DecimalStyle {

 /**
 * The standard set of non-localized decimal style symbols.
 * <p>
 * This uses standard ASCII characters for zero, positive, negative and a dot for the decimal point.
 */
 public static final DecimalStyle STANDARD = new DecimalStyle('0', '+', '-', '.');
 /**
 * The cache of DecimalStyle instances.
 */
 private static final ConcurrentMap<Locale, DecimalStyle> CACHE = new ConcurrentHashMap<>(16, 0.75f, 2);

 /**
 * The zero digit.
 */
 private final char zeroDigit;
 /**
 * The positive sign.
 */
 private final char positiveSign;
 /**
 * The negative sign.
 */
 private final char negativeSign;
 /**
 * The decimal separator.
 */
 private final char decimalSeparator;

 //-----------------------------------------------------------------------
 /**
 * Lists all the locales that are supported.
 * <p>
 * The locale 'en_US' will always be present.
 *
 * @return a Set of Locales for which localization is supported
 */
 public static Set<Locale> getAvailableLocales() {
 Locale[] l = DecimalFormatSymbols.getAvailableLocales();
 Set<Locale> locales = new HashSet<>(l.length);
 Collections.addAll(locales, l);
 return locales;
 }

 /**
 * Obtains the DecimalStyle for the default
 * {@link java.util.Locale.Category#FORMAT FORMAT} locale.
 * <p>
 * This method provides access to locale sensitive decimal style symbols.
 * <p>
 * This is equivalent to calling
 * {@link #of(Locale)
 * of(Locale.getDefault(Locale.Category.FORMAT))}.
 *
 * @see java.util.Locale.Category#FORMAT
 * @return the decimal style, not null
 */
 public static DecimalStyle ofDefaultLocale() {
 return of(Locale.getDefault(Locale.Category.FORMAT));
 }

 /**
 * Obtains the DecimalStyle for the specified locale.
 * <p>
 * This method provides access to locale sensitive decimal style symbols.
 * If the locale contains "nu" (Numbering System) and/or "rg"
 * (Region Override) <a href="../../util/Locale.html#def_locale_extension">
 * Unicode extensions</a>, returned instance will reflect the values specified with
 * those extensions. If both "nu" and "rg" are specified, the value from
 * the "nu" extension supersedes the implicit one from the "rg" extension.
 *
 * @param locale the locale, not null
 * @return the decimal style, not null
 */
 public static DecimalStyle of(Locale locale) {
 Objects.requireNonNull(locale, "locale");
 DecimalStyle info = CACHE.get(locale);
 if (info == null) {
 info = create(locale);
 CACHE.putIfAbsent(locale, info);
 info = CACHE.get(locale);
 }
 return info;
 }

 private static DecimalStyle create(Locale locale) {
 DecimalFormatSymbols oldSymbols = DecimalFormatSymbols.getInstance(locale);
 char zeroDigit = oldSymbols.getZeroDigit();
 char positiveSign = '+';
 char negativeSign = oldSymbols.getMinusSign();
 char decimalSeparator = oldSymbols.getDecimalSeparator();
 if (zeroDigit == '0' && negativeSign == '-' && decimalSeparator == '.') {
 return STANDARD;
 }
 return new DecimalStyle(zeroDigit, positiveSign, negativeSign, decimalSeparator);
 }

 //-----------------------------------------------------------------------
 /**
 * Restricted constructor.
 *
 * @param zeroChar the character to use for the digit of zero
 * @param positiveSignChar the character to use for the positive sign
 * @param negativeSignChar the character to use for the negative sign
 * @param decimalPointChar the character to use for the decimal point
 */
 private DecimalStyle(char zeroChar, char positiveSignChar, char negativeSignChar, char decimalPointChar) {
 this.zeroDigit = zeroChar;
 this.positiveSign = positiveSignChar;
 this.negativeSign = negativeSignChar;
 this.decimalSeparator = decimalPointChar;
 }

 //-----------------------------------------------------------------------
 /**
 * Gets the character that represents zero.
 * <p>
 * The character used to represent digits may vary by culture.
 * This method specifies the zero character to use, which implies the characters for one to nine.
 *
 * @return the character for zero
 */
 public char getZeroDigit() {
 return zeroDigit;
 }

 /**
 * Returns a copy of the info with a new character that represents zero.
 * <p>
 * The character used to represent digits may vary by culture.
 * This method specifies the zero character to use, which implies the characters for one to nine.
 *
 * @param zeroDigit the character for zero
 * @return a copy with a new character that represents zero, not null
 */
 public DecimalStyle withZeroDigit(char zeroDigit) {
 if (zeroDigit == this.zeroDigit) {
 return this;
 }
 return new DecimalStyle(zeroDigit, positiveSign, negativeSign, decimalSeparator);
 }

 //-----------------------------------------------------------------------
 /**
 * Gets the character that represents the positive sign.
 * <p>
 * The character used to represent a positive number may vary by culture.
 * This method specifies the character to use.
 *
 * @return the character for the positive sign
 */
 public char getPositiveSign() {
 return positiveSign;
 }

 /**
 * Returns a copy of the info with a new character that represents the positive sign.
 * <p>
 * The character used to represent a positive number may vary by culture.
 * This method specifies the character to use.
 *
 * @param positiveSign the character for the positive sign
 * @return a copy with a new character that represents the positive sign, not null
 */
 public DecimalStyle withPositiveSign(char positiveSign) {
 if (positiveSign == this.positiveSign) {
 return this;
 }
 return new DecimalStyle(zeroDigit, positiveSign, negativeSign, decimalSeparator);
 }

 //-----------------------------------------------------------------------
 /**
 * Gets the character that represents the negative sign.
 * <p>
 * The character used to represent a negative number may vary by culture.
 * This method specifies the character to use.
 *
 * @return the character for the negative sign
 */
 public char getNegativeSign() {
 return negativeSign;
 }

 /**
 * Returns a copy of the info with a new character that represents the negative sign.
 * <p>
 * The character used to represent a negative number may vary by culture.
 * This method specifies the character to use.
 *
 * @param negativeSign the character for the negative sign
 * @return a copy with a new character that represents the negative sign, not null
 */
 public DecimalStyle withNegativeSign(char negativeSign) {
 if (negativeSign == this.negativeSign) {
 return this;
 }
 return new DecimalStyle(zeroDigit, positiveSign, negativeSign, decimalSeparator);
 }

 //-----------------------------------------------------------------------
 /**
 * Gets the character that represents the decimal point.
 * <p>
 * The character used to represent a decimal point may vary by culture.
 * This method specifies the character to use.
 *
 * @return the character for the decimal point
 */
 public char getDecimalSeparator() {
 return decimalSeparator;
 }

 /**
 * Returns a copy of the info with a new character that represents the decimal point.
 * <p>
 * The character used to represent a decimal point may vary by culture.
 * This method specifies the character to use.
 *
 * @param decimalSeparator the character for the decimal point
 * @return a copy with a new character that represents the decimal point, not null
 */
 public DecimalStyle withDecimalSeparator(char decimalSeparator) {
 if (decimalSeparator == this.decimalSeparator) {
 return this;
 }
 return new DecimalStyle(zeroDigit, positiveSign, negativeSign, decimalSeparator);
 }

 //-----------------------------------------------------------------------
 /**
 * Checks whether the character is a digit, based on the currently set zero character.
 *
 * @param ch the character to check
 * @return the value, 0 to 9, of the character, or -1 if not a digit
 */
 int convertToDigit(char ch) {
 int val = ch - zeroDigit;
 return (val >= 0 && val <= 9) ? val : -1;
 }

 /**
 * Converts the input numeric text to the internationalized form using the zero character.
 *
 * @param numericText the text, consisting of digits 0 to 9, to convert, not null
 * @return the internationalized text, not null
 */
 String convertNumberToI18N(String numericText) {
 if (zeroDigit == '0') {
 return numericText;
 }
 int diff = zeroDigit - '0';
 char[] array = numericText.toCharArray();
 for (int i = 0; i < array.length; i++) {
 array[i] = (char) (array[i] + diff);
 }
 return new String(array);
 }

 //-----------------------------------------------------------------------
 /**
 * Checks if this DecimalStyle is equal to another DecimalStyle.
 *
 * @param obj the object to check, null returns false
 * @return true if this is equal to the other date
 */
 @Override
 public boolean equals(Object obj) {
 if (this == obj) {
 return true;
 }
 if (obj instanceof DecimalStyle) {
 DecimalStyle other = (DecimalStyle) obj;
 return (zeroDigit == other.zeroDigit && positiveSign == other.positiveSign &&
 negativeSign == other.negativeSign && decimalSeparator == other.decimalSeparator);
 }
 return false;
 }

 /**
 * A hash code for this DecimalStyle.
 *
 * @return a suitable hash code
 */
 @Override
 public int hashCode() {
 return zeroDigit + positiveSign + negativeSign + decimalSeparator;
 }

 //-----------------------------------------------------------------------
 /**
 * Returns a string describing this DecimalStyle.
 *
 * @return a string description, not null
 */
 @Override
 public String toString() {
 return "DecimalStyle[" + zeroDigit + positiveSign + negativeSign + decimalSeparator + "]";
 }

}