001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.tools.date;
003
004import java.text.DateFormat;
005import java.text.ParsePosition;
006import java.text.SimpleDateFormat;
007import java.time.Instant;
008import java.time.ZoneId;
009import java.time.ZoneOffset;
010import java.time.ZonedDateTime;
011import java.time.format.DateTimeFormatter;
012import java.util.Date;
013import java.util.Locale;
014import java.util.TimeZone;
015
016import javax.xml.datatype.DatatypeConfigurationException;
017import javax.xml.datatype.DatatypeFactory;
018
019import org.openstreetmap.josm.Main;
020import org.openstreetmap.josm.data.preferences.BooleanProperty;
021import org.openstreetmap.josm.tools.CheckParameterUtil;
022import org.openstreetmap.josm.tools.UncheckedParseException;
023
024/**
025 * A static utility class dealing with:
026 * <ul>
027 * <li>parsing XML date quickly and formatting a date to the XML UTC format regardless of current locale</li>
028 * <li>providing a single entry point for formatting dates to be displayed in JOSM GUI, based on user preferences</li>
029 * </ul>
030 * @author nenik
031 */
032public final class DateUtils {
033
034    /**
035     * The UTC time zone.
036     */
037    public static final TimeZone UTC = TimeZone.getTimeZone("UTC");
038
039    /**
040     * Property to enable display of ISO dates globally.
041     * @since 7299
042     */
043    public static final BooleanProperty PROP_ISO_DATES = new BooleanProperty("iso.dates", false);
044
045    private static final DatatypeFactory XML_DATE;
046
047    static {
048        DatatypeFactory fact = null;
049        try {
050            fact = DatatypeFactory.newInstance();
051        } catch (DatatypeConfigurationException ce) {
052            Main.error(ce);
053        }
054        XML_DATE = fact;
055    }
056
057    protected DateUtils() {
058        // Hide default constructor for utils classes
059    }
060
061    /**
062     * Parses XML date quickly, regardless of current locale.
063     * @param str The XML date as string
064     * @return The date
065     * @throws UncheckedParseException if the date does not match any of the supported date formats
066     */
067    public static synchronized Date fromString(String str) {
068        return new Date(tsFromString(str));
069    }
070
071    /**
072     * Parses XML date quickly, regardless of current locale.
073     * @param str The XML date as string
074     * @return The date in milliseconds since epoch
075     * @throws UncheckedParseException if the date does not match any of the supported date formats
076     */
077    public static synchronized long tsFromString(String str) {
078        // "2007-07-25T09:26:24{Z|{+|-}01[:00]}"
079        if (checkLayout(str, "xxxx-xx-xxTxx:xx:xxZ") ||
080                checkLayout(str, "xxxx-xx-xxTxx:xx:xx") ||
081                checkLayout(str, "xxxx:xx:xx xx:xx:xx") ||
082                checkLayout(str, "xxxx-xx-xx xx:xx:xx UTC") ||
083                checkLayout(str, "xxxx-xx-xxTxx:xx:xx+xx") ||
084                checkLayout(str, "xxxx-xx-xxTxx:xx:xx-xx") ||
085                checkLayout(str, "xxxx-xx-xxTxx:xx:xx+xx:00") ||
086                checkLayout(str, "xxxx-xx-xxTxx:xx:xx-xx:00")) {
087            final ZonedDateTime local = ZonedDateTime.of(
088                parsePart4(str, 0),
089                parsePart2(str, 5),
090                parsePart2(str, 8),
091                parsePart2(str, 11),
092                parsePart2(str, 14),
093                parsePart2(str, 17),
094                0,
095                // consider EXIF date in default timezone
096                checkLayout(str, "xxxx:xx:xx xx:xx:xx") ? ZoneId.systemDefault() : ZoneOffset.UTC
097            );
098            if (str.length() == 22 || str.length() == 25) {
099                final int plusHr = parsePart2(str, 20);
100                final long mul = str.charAt(19) == '+' ? -1 : 1;
101                return local.plusHours(plusHr * mul).toInstant().toEpochMilli();
102            }
103            return local.toInstant().toEpochMilli();
104        } else if (checkLayout(str, "xxxx-xx-xxTxx:xx:xx.xxxZ") ||
105                checkLayout(str, "xxxx-xx-xxTxx:xx:xx.xxx") ||
106                checkLayout(str, "xxxx:xx:xx xx:xx:xx.xxx") ||
107                checkLayout(str, "xxxx-xx-xxTxx:xx:xx.xxx+xx:00") ||
108                checkLayout(str, "xxxx-xx-xxTxx:xx:xx.xxx-xx:00")) {
109            final ZonedDateTime local = ZonedDateTime.of(
110                parsePart4(str, 0),
111                parsePart2(str, 5),
112                parsePart2(str, 8),
113                parsePart2(str, 11),
114                parsePart2(str, 14),
115                parsePart2(str, 17),
116                parsePart3(str, 20) * 1_000_000,
117                // consider EXIF date in default timezone
118                checkLayout(str, "xxxx:xx:xx xx:xx:xx.xxx") ? ZoneId.systemDefault() : ZoneOffset.UTC
119            );
120            if (str.length() == 29) {
121                final int plusHr = parsePart2(str, 24);
122                final long mul = str.charAt(23) == '+' ? -1 : 1;
123                return local.plusHours(plusHr * mul).toInstant().toEpochMilli();
124            }
125            return local.toInstant().toEpochMilli();
126        } else {
127            // example date format "18-AUG-08 13:33:03"
128            SimpleDateFormat f = new SimpleDateFormat("dd-MMM-yy HH:mm:ss");
129            Date d = f.parse(str, new ParsePosition(0));
130            if (d != null)
131                return d.getTime();
132        }
133
134        try {
135            return XML_DATE.newXMLGregorianCalendar(str).toGregorianCalendar().getTimeInMillis();
136        } catch (IllegalArgumentException ex) {
137            throw new UncheckedParseException("The date string (" + str + ") could not be parsed.", ex);
138        }
139    }
140
141    /**
142     * Formats a date to the XML UTC format regardless of current locale.
143     * @param timestamp number of seconds since the epoch
144     * @return The formatted date
145     */
146    public static synchronized String fromTimestamp(int timestamp) {
147        final ZonedDateTime temporal = Instant.ofEpochMilli(timestamp * 1000L).atZone(ZoneOffset.UTC);
148        return DateTimeFormatter.ISO_OFFSET_DATE_TIME.format(temporal);
149    }
150
151    /**
152     * Formats a date to the XML UTC format regardless of current locale.
153     * @param date The date to format
154     * @return The formatted date
155     */
156    public static synchronized String fromDate(Date date) {
157        final ZonedDateTime temporal = date.toInstant().atZone(ZoneOffset.UTC);
158        return DateTimeFormatter.ISO_OFFSET_DATE_TIME.format(temporal);
159    }
160
161    private static boolean checkLayout(String text, String pattern) {
162        if (text.length() != pattern.length())
163            return false;
164        for (int i = 0; i < pattern.length(); i++) {
165            char pc = pattern.charAt(i);
166            char tc = text.charAt(i);
167            if (pc == 'x' && Character.isDigit(tc))
168                continue;
169            else if (pc == 'x' || pc != tc)
170                return false;
171        }
172        return true;
173    }
174
175    private static int num(char c) {
176        return c - '0';
177    }
178
179    private static int parsePart2(String str, int off) {
180        return 10 * num(str.charAt(off)) + num(str.charAt(off + 1));
181    }
182
183    private static int parsePart3(String str, int off) {
184        return 100 * num(str.charAt(off)) + 10 * num(str.charAt(off + 1)) + num(str.charAt(off + 2));
185    }
186
187    private static int parsePart4(String str, int off) {
188        return 1000 * num(str.charAt(off)) + 100 * num(str.charAt(off + 1)) + 10 * num(str.charAt(off + 2)) + num(str.charAt(off + 3));
189    }
190
191    /**
192     * Returns a new {@code SimpleDateFormat} for date only, according to <a href="https://en.wikipedia.org/wiki/ISO_8601">ISO 8601</a>.
193     * @return a new ISO 8601 date format, for date only.
194     * @since 7299
195     */
196    public static SimpleDateFormat newIsoDateFormat() {
197        return new SimpleDateFormat("yyyy-MM-dd");
198    }
199
200    /**
201     * Returns a new {@code SimpleDateFormat} for date and time, according to <a href="https://en.wikipedia.org/wiki/ISO_8601">ISO 8601</a>.
202     * @return a new ISO 8601 date format, for date and time.
203     * @since 7299
204     */
205    public static SimpleDateFormat newIsoDateTimeFormat() {
206        return new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssX");
207    }
208
209    /**
210     * Returns a new {@code SimpleDateFormat} for date and time, according to format used in OSM API errors.
211     * @return a new date format, for date and time, to use for OSM API error handling.
212     * @since 7299
213     */
214    public static SimpleDateFormat newOsmApiDateTimeFormat() {
215        // Example: "2010-09-07 14:39:41 UTC".
216        // Always parsed with US locale regardless of the current locale in JOSM
217        return new SimpleDateFormat("yyyy-MM-dd HH:mm:ss z", Locale.US);
218    }
219
220    /**
221     * Returns the date format to be used for current user, based on user preferences.
222     * @param dateStyle The date style as described in {@link DateFormat#getDateInstance}. Ignored if "ISO dates" option is set
223     * @return The date format
224     * @since 7299
225     */
226    public static DateFormat getDateFormat(int dateStyle) {
227        if (PROP_ISO_DATES.get()) {
228            return newIsoDateFormat();
229        } else {
230            return DateFormat.getDateInstance(dateStyle, Locale.getDefault());
231        }
232    }
233
234    /**
235     * Formats a date to be displayed to current user, based on user preferences.
236     * @param date The date to display. Must not be {@code null}
237     * @param dateStyle The date style as described in {@link DateFormat#getDateInstance}. Ignored if "ISO dates" option is set
238     * @return The formatted date
239     * @since 7299
240     */
241    public static String formatDate(Date date, int dateStyle) {
242        CheckParameterUtil.ensureParameterNotNull(date, "date");
243        return getDateFormat(dateStyle).format(date);
244    }
245
246    /**
247     * Returns the time format to be used for current user, based on user preferences.
248     * @param timeStyle The time style as described in {@link DateFormat#getTimeInstance}. Ignored if "ISO dates" option is set
249     * @return The time format
250     * @since 7299
251     */
252    public static DateFormat getTimeFormat(int timeStyle) {
253        if (PROP_ISO_DATES.get()) {
254            // This is not strictly conform to ISO 8601. We just want to avoid US-style times such as 3.30pm
255            return new SimpleDateFormat("HH:mm:ss");
256        } else {
257            return DateFormat.getTimeInstance(timeStyle, Locale.getDefault());
258        }
259    }
260
261    /**
262     * Formats a time to be displayed to current user, based on user preferences.
263     * @param time The time to display. Must not be {@code null}
264     * @param timeStyle The time style as described in {@link DateFormat#getTimeInstance}. Ignored if "ISO dates" option is set
265     * @return The formatted time
266     * @since 7299
267     */
268    public static String formatTime(Date time, int timeStyle) {
269        CheckParameterUtil.ensureParameterNotNull(time, "time");
270        return getTimeFormat(timeStyle).format(time);
271    }
272
273    /**
274     * Returns the date/time format to be used for current user, based on user preferences.
275     * @param dateStyle The date style as described in {@link DateFormat#getDateTimeInstance}. Ignored if "ISO dates" option is set
276     * @param timeStyle The time style as described in {@code DateFormat.getDateTimeInstance}. Ignored if "ISO dates" option is set
277     * @return The date/time format
278     * @since 7299
279     */
280    public static DateFormat getDateTimeFormat(int dateStyle, int timeStyle) {
281        if (PROP_ISO_DATES.get()) {
282            // This is not strictly conform to ISO 8601. We just want to avoid US-style times such as 3.30pm
283            // and we don't want to use the 'T' separator as a space character is much more readable
284            return new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
285        } else {
286            return DateFormat.getDateTimeInstance(dateStyle, timeStyle, Locale.getDefault());
287        }
288    }
289
290    /**
291     * Formats a date/time to be displayed to current user, based on user preferences.
292     * @param datetime The date/time to display. Must not be {@code null}
293     * @param dateStyle The date style as described in {@link DateFormat#getDateTimeInstance}. Ignored if "ISO dates" option is set
294     * @param timeStyle The time style as described in {@code DateFormat.getDateTimeInstance}. Ignored if "ISO dates" option is set
295     * @return The formatted date/time
296     * @since 7299
297     */
298    public static String formatDateTime(Date datetime, int dateStyle, int timeStyle) {
299        CheckParameterUtil.ensureParameterNotNull(datetime, "datetime");
300        return getDateTimeFormat(dateStyle, timeStyle).format(datetime);
301    }
302}