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/*
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 * However, the following notice accompanied the original version of this
 * file:
 *
 * Copyright (c) 2007-2012, Stephen Colebourne & Michael Nascimento Santos
 *
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package java.time;

import static java.time.temporal.ChronoField.DAY_OF_WEEK;
import static java.time.temporal.ChronoUnit.DAYS;

import java.time.format.DateTimeFormatterBuilder;
import java.time.format.TextStyle;
import java.time.temporal.ChronoField;
import java.time.temporal.Temporal;
import java.time.temporal.TemporalAccessor;
import java.time.temporal.TemporalAdjuster;
import java.time.temporal.TemporalField;
import java.time.temporal.TemporalQueries;
import java.time.temporal.TemporalQuery;
import java.time.temporal.UnsupportedTemporalTypeException;
import java.time.temporal.ValueRange;
import java.time.temporal.WeekFields;
import java.util.Locale;

/**
 * A day-of-week, such as 'Tuesday'.
 * <p>
 * {@code DayOfWeek} is an enum representing the 7 days of the week -
 * Monday, Tuesday, Wednesday, Thursday, Friday, Saturday and Sunday.
 * <p>
 * In addition to the textual enum name, each day-of-week has an {@code int} value.
 * The {@code int} value follows the ISO-8601 standard, from 1 (Monday) to 7 (Sunday).
 * It is recommended that applications use the enum rather than the {@code int} value
 * to ensure code clarity.
 * <p>
 * This enum provides access to the localized textual form of the day-of-week.
 * Some locales also assign different numeric values to the days, declaring
 * Sunday to have the value 1, however this class provides no support for this.
 * See {@link WeekFields} for localized week-numbering.
 * <p>
 * <b>Do not use {@code ordinal()} to obtain the numeric representation of {@code DayOfWeek}.
 * Use {@code getValue()} instead.</b>
 * <p>
 * This enum represents a common concept that is found in many calendar systems.
 * As such, this enum may be used by any calendar system that has the day-of-week
 * concept defined exactly equivalent to the ISO calendar system.
 *
 * @implSpec
 * This is an immutable and thread-safe enum.
 *
 * @since 1.8
 */
public enum DayOfWeek implements TemporalAccessor, TemporalAdjuster {

 /**
 * The singleton instance for the day-of-week of Monday.
 * This has the numeric value of {@code 1}.
 */
 MONDAY,
 /**
 * The singleton instance for the day-of-week of Tuesday.
 * This has the numeric value of {@code 2}.
 */
 TUESDAY,
 /**
 * The singleton instance for the day-of-week of Wednesday.
 * This has the numeric value of {@code 3}.
 */
 WEDNESDAY,
 /**
 * The singleton instance for the day-of-week of Thursday.
 * This has the numeric value of {@code 4}.
 */
 THURSDAY,
 /**
 * The singleton instance for the day-of-week of Friday.
 * This has the numeric value of {@code 5}.
 */
 FRIDAY,
 /**
 * The singleton instance for the day-of-week of Saturday.
 * This has the numeric value of {@code 6}.
 */
 SATURDAY,
 /**
 * The singleton instance for the day-of-week of Sunday.
 * This has the numeric value of {@code 7}.
 */
 SUNDAY;
 /**
 * Private cache of all the constants.
 */
 private static final DayOfWeek[] ENUMS = DayOfWeek.values();

 //-----------------------------------------------------------------------
 /**
 * Obtains an instance of {@code DayOfWeek} from an {@code int} value.
 * <p>
 * {@code DayOfWeek} is an enum representing the 7 days of the week.
 * This factory allows the enum to be obtained from the {@code int} value.
 * The {@code int} value follows the ISO-8601 standard, from 1 (Monday) to 7 (Sunday).
 *
 * @param dayOfWeek the day-of-week to represent, from 1 (Monday) to 7 (Sunday)
 * @return the day-of-week singleton, not null
 * @throws DateTimeException if the day-of-week is invalid
 */
 public static DayOfWeek of(int dayOfWeek) {
 if (dayOfWeek < 1 || dayOfWeek > 7) {
 throw new DateTimeException("Invalid value for DayOfWeek: " + dayOfWeek);
 }
 return ENUMS[dayOfWeek - 1];
 }

 //-----------------------------------------------------------------------
 /**
 * Obtains an instance of {@code DayOfWeek} from a temporal object.
 * <p>
 * This obtains a day-of-week based on the specified temporal.
 * A {@code TemporalAccessor} represents an arbitrary set of date and time information,
 * which this factory converts to an instance of {@code DayOfWeek}.
 * <p>
 * The conversion extracts the {@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} field.
 * <p>
 * This method matches the signature of the functional interface {@link TemporalQuery}
 * allowing it to be used as a query via method reference, {@code DayOfWeek::from}.
 *
 * @param temporal the temporal object to convert, not null
 * @return the day-of-week, not null
 * @throws DateTimeException if unable to convert to a {@code DayOfWeek}
 */
 public static DayOfWeek from(TemporalAccessor temporal) {
 if (temporal instanceof DayOfWeek) {
 return (DayOfWeek) temporal;
 }
 try {
 return of(temporal.get(DAY_OF_WEEK));
 } catch (DateTimeException ex) {
 throw new DateTimeException("Unable to obtain DayOfWeek from TemporalAccessor: " +
 temporal + " of type " + temporal.getClass().getName(), ex);
 }
 }

 //-----------------------------------------------------------------------
 /**
 * Gets the day-of-week {@code int} value.
 * <p>
 * The values are numbered following the ISO-8601 standard, from 1 (Monday) to 7 (Sunday).
 * See {@link java.time.temporal.WeekFields#dayOfWeek()} for localized week-numbering.
 *
 * @return the day-of-week, from 1 (Monday) to 7 (Sunday)
 */
 public int getValue() {
 return ordinal() + 1;
 }

 //-----------------------------------------------------------------------
 /**
 * Gets the textual representation, such as 'Mon' or 'Friday'.
 * <p>
 * This returns the textual name used to identify the day-of-week,
 * suitable for presentation to the user.
 * The parameters control the style of the returned text and the locale.
 * <p>
 * If no textual mapping is found then the {@link #getValue() numeric value} is returned.
 *
 * @param style the length of the text required, not null
 * @param locale the locale to use, not null
 * @return the text value of the day-of-week, not null
 */
 public String getDisplayName(TextStyle style, Locale locale) {
 return new DateTimeFormatterBuilder().appendText(DAY_OF_WEEK, style).toFormatter(locale).format(this);
 }

 //-----------------------------------------------------------------------
 /**
 * Checks if the specified field is supported.
 * <p>
 * This checks if this day-of-week can be queried for the specified field.
 * If false, then calling the {@link #range(TemporalField) range} and
 * {@link #get(TemporalField) get} methods will throw an exception.
 * <p>
 * If the field is {@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} then
 * this method returns true.
 * All other {@code ChronoField} instances will return false.
 * <p>
 * If the field is not a {@code ChronoField}, then the result of this method
 * is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)}
 * passing {@code this} as the argument.
 * Whether the field is supported is determined by the field.
 *
 * @param field the field to check, null returns false
 * @return true if the field is supported on this day-of-week, false if not
 */
 @Override
 public boolean isSupported(TemporalField field) {
 if (field instanceof ChronoField) {
 return field == DAY_OF_WEEK;
 }
 return field != null && field.isSupportedBy(this);
 }

 /**
 * Gets the range of valid values for the specified field.
 * <p>
 * The range object expresses the minimum and maximum valid values for a field.
 * This day-of-week is used to enhance the accuracy of the returned range.
 * If it is not possible to return the range, because the field is not supported
 * or for some other reason, an exception is thrown.
 * <p>
 * If the field is {@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} then the
 * range of the day-of-week, from 1 to 7, will be returned.
 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
 * <p>
 * If the field is not a {@code ChronoField}, then the result of this method
 * is obtained by invoking {@code TemporalField.rangeRefinedBy(TemporalAccessor)}
 * passing {@code this} as the argument.
 * Whether the range can be obtained is determined by the field.
 *
 * @param field the field to query the range for, not null
 * @return the range of valid values for the field, not null
 * @throws DateTimeException if the range for the field cannot be obtained
 * @throws UnsupportedTemporalTypeException if the field is not supported
 */
 @Override
 public ValueRange range(TemporalField field) {
 if (field == DAY_OF_WEEK) {
 return field.range();
 }
 return TemporalAccessor.super.range(field);
 }

 /**
 * Gets the value of the specified field from this day-of-week as an {@code int}.
 * <p>
 * This queries this day-of-week for the value of the specified field.
 * The returned value will always be within the valid range of values for the field.
 * If it is not possible to return the value, because the field is not supported
 * or for some other reason, an exception is thrown.
 * <p>
 * If the field is {@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} then the
 * value of the day-of-week, from 1 to 7, will be returned.
 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
 * <p>
 * If the field is not a {@code ChronoField}, then the result of this method
 * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
 * passing {@code this} as the argument. Whether the value can be obtained,
 * and what the value represents, is determined by the field.
 *
 * @param field the field to get, not null
 * @return the value for the field, within the valid range of values
 * @throws DateTimeException if a value for the field cannot be obtained or
 * the value is outside the range of valid values for the field
 * @throws UnsupportedTemporalTypeException if the field is not supported or
 * the range of values exceeds an {@code int}
 * @throws ArithmeticException if numeric overflow occurs
 */
 @Override
 public int get(TemporalField field) {
 if (field == DAY_OF_WEEK) {
 return getValue();
 }
 return TemporalAccessor.super.get(field);
 }

 /**
 * Gets the value of the specified field from this day-of-week as a {@code long}.
 * <p>
 * This queries this day-of-week for the value of the specified field.
 * If it is not possible to return the value, because the field is not supported
 * or for some other reason, an exception is thrown.
 * <p>
 * If the field is {@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} then the
 * value of the day-of-week, from 1 to 7, will be returned.
 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
 * <p>
 * If the field is not a {@code ChronoField}, then the result of this method
 * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
 * passing {@code this} as the argument. Whether the value can be obtained,
 * and what the value represents, is determined by the field.
 *
 * @param field the field to get, not null
 * @return the value for the field
 * @throws DateTimeException if a value for the field cannot be obtained
 * @throws UnsupportedTemporalTypeException if the field is not supported
 * @throws ArithmeticException if numeric overflow occurs
 */
 @Override
 public long getLong(TemporalField field) {
 if (field == DAY_OF_WEEK) {
 return getValue();
 } else if (field instanceof ChronoField) {
 throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
 }
 return field.getFrom(this);
 }

 //-----------------------------------------------------------------------
 /**
 * Returns the day-of-week that is the specified number of days after this one.
 * <p>
 * The calculation rolls around the end of the week from Sunday to Monday.
 * The specified period may be negative.
 * <p>
 * This instance is immutable and unaffected by this method call.
 *
 * @param days the days to add, positive or negative
 * @return the resulting day-of-week, not null
 */
 public DayOfWeek plus(long days) {
 int amount = (int) (days % 7);
 return ENUMS[(ordinal() + (amount + 7)) % 7];
 }

 /**
 * Returns the day-of-week that is the specified number of days before this one.
 * <p>
 * The calculation rolls around the start of the year from Monday to Sunday.
 * The specified period may be negative.
 * <p>
 * This instance is immutable and unaffected by this method call.
 *
 * @param days the days to subtract, positive or negative
 * @return the resulting day-of-week, not null
 */
 public DayOfWeek minus(long days) {
 return plus(-(days % 7));
 }

 //-----------------------------------------------------------------------
 /**
 * Queries this day-of-week using the specified query.
 * <p>
 * This queries this day-of-week using the specified query strategy object.
 * The {@code TemporalQuery} object defines the logic to be used to
 * obtain the result. Read the documentation of the query to understand
 * what the result of this method will be.
 * <p>
 * The result of this method is obtained by invoking the
 * {@link TemporalQuery#queryFrom(TemporalAccessor)} method on the
 * specified query passing {@code this} as the argument.
 *
 * @param <R> the type of the result
 * @param query the query to invoke, not null
 * @return the query result, null may be returned (defined by the query)
 * @throws DateTimeException if unable to query (defined by the query)
 * @throws ArithmeticException if numeric overflow occurs (defined by the query)
 */
 @SuppressWarnings("unchecked")
 @Override
 public <R> R query(TemporalQuery<R> query) {
 if (query == TemporalQueries.precision()) {
 return (R) DAYS;
 }
 return TemporalAccessor.super.query(query);
 }

 /**
 * Adjusts the specified temporal object to have this day-of-week.
 * <p>
 * This returns a temporal object of the same observable type as the input
 * with the day-of-week changed to be the same as this.
 * <p>
 * The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}
 * passing {@link ChronoField#DAY_OF_WEEK} as the field.
 * Note that this adjusts forwards or backwards within a Monday to Sunday week.
 * See {@link java.time.temporal.WeekFields#dayOfWeek()} for localized week start days.
 * See {@code TemporalAdjuster} for other adjusters with more control,
 * such as {@code next(MONDAY)}.
 * <p>
 * In most cases, it is clearer to reverse the calling pattern by using
 * {@link Temporal#with(TemporalAdjuster)}:
 * <pre>
 * // these two lines are equivalent, but the second approach is recommended
 * temporal = thisDayOfWeek.adjustInto(temporal);
 * temporal = temporal.with(thisDayOfWeek);
 * </pre>
 * <p>
 * For example, given a date that is a Wednesday, the following are output:
 * <pre>
 * dateOnWed.with(MONDAY); // two days earlier
 * dateOnWed.with(TUESDAY); // one day earlier
 * dateOnWed.with(WEDNESDAY); // same date
 * dateOnWed.with(THURSDAY); // one day later
 * dateOnWed.with(FRIDAY); // two days later
 * dateOnWed.with(SATURDAY); // three days later
 * dateOnWed.with(SUNDAY); // four days later
 * </pre>
 * <p>
 * This instance is immutable and unaffected by this method call.
 *
 * @param temporal the target object to be adjusted, not null
 * @return the adjusted object, not null
 * @throws DateTimeException if unable to make the adjustment
 * @throws ArithmeticException if numeric overflow occurs
 */
 @Override
 public Temporal adjustInto(Temporal temporal) {
 return temporal.with(DAY_OF_WEEK, getValue());
 }

}