Added Year, Month, Week feature

lib/date_time.dart

@@ -3,7 +3,11 @@ library date_time;
 export 'src/date.dart';
 export 'src/date_range.dart';
 export 'src/date_time_error.dart';
+export 'src/date_time_range.dart';
 export 'src/extensions.dart';
+export 'src/month.dart';
 export 'src/overflowed_time.dart';
 export 'src/time.dart';
 export 'src/time_range.dart';
+export 'src/week.dart';
+export 'src/year.dart';

lib/src/date.dart

@@ -1,5 +1,8 @@
 import 'package:clock/clock.dart';
 import 'package:date_time/src/extensions.dart';
+import 'package:date_time/src/month.dart';
+import 'package:date_time/src/week.dart';
+import 'package:date_time/src/year.dart';
 import 'package:intl/intl.dart';
 import 'package:quiver/core.dart';
 
@@ -106,6 +109,11 @@ class Date {
 
  DateTime get asUtcDateTime => DateTime.utc(year, month, day);
 
+ ///////////////////////////////////// OPERATIONS
+
+ /// Return the difference in days
+ int difference(Date other) => asDateTime.difference(other.asDateTime).inDays;
+
  /// Add a [Duration] to this date
  Date add(Duration duration) {
  final t = asUtcDateTime.add(duration);
@@ -142,7 +150,9 @@ class Date {
  /// Add a certain amount of quarters to this date
  Date subQuarters(int amount) => addQuarters(-amount);
 
- // DateTime subWeeks(amount)
+ /// Subtracts an amount of weeks from this [Date]
+ Date subWeeks(int amount) => subDays(amount * 7);
+
  /// Subtracts an amount of years from this [Date]
  Date subYears(int amount) => addYears(-amount);
 
@@ -254,6 +264,29 @@ class Date {
  return woy;
  }
 
+ /// Returns the year of this [Date]'s week
+ int get yearOfWeek => addDays(1).yearOfISOWeek;
+
+ /// Returns the year for this [Date] ISO week
+ int get yearOfISOWeek {
+ final woy = (_ordinalDate - weekday + 10) ~/ 7;
+
+ // If the week number equals zero, it means that the given date belongs to the preceding (week-based) year.
+ if (woy == 0) {
+ // The 28th of December is always in the last week of the year
+ return year - 1;
+ }
+
+ // If the week number equals 53, one must check that the date is not actually in week 1 of the following year
+ if (woy == 53 &&
+ DateTime(year).weekday != DateTime.thursday &&
+ DateTime(year, 12, 31).weekday != DateTime.thursday) {
+ return year + 1;
+ }
+
+ return year;
+ }
+
  int get _ordinalDate {
  const offsets = [0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334];
  return offsets[month - 1] + day + (isLeapYear && month > 2 ? 1 : 0);
@@ -296,6 +329,22 @@ class Date {
  /// Return true if this date [isBefore] [Date.now]
  bool get isPast => isBefore(Date.today());
 
+ /// Return the start of day in [DateTime]
+ DateTime get startOfDay => asDateTime.startOfDay;
+
+ /// Return the end of day in [DateTime]
+ DateTime get endOfDay => asDateTime.endOfDay;
+
+ ///////////////////////////////////// COMPARISON
+
+ int compareTo(Date other) => asDateTime.compareTo(other.asDateTime);
+
+ /// Check if the date is within [start] and [end]
+ bool isWithinRange(Date start, Date end) => this >= start && this <= end;
+
+ /// Check if the date is out side [start] and [end]
+ bool isOutsideRange(Date start, Date end) => !isWithinRange(start, end);
+
  /// Check if this date is in the same day than other
  bool isSameDay(Date other) => this == other;
 
@@ -342,12 +391,16 @@ class Date {
  bool get isWeekend =>
  weekday == DateTime.saturday || weekday == DateTime.sunday;
 
+ /// Greater than
  bool operator >(Date other) => isAfter(other);
 
+ /// Greater than or equal
  bool operator >=(Date other) => isSameOrAfter(other);
 
+ /// Less than
  bool operator <(Date other) => isBefore(other);
 
+ /// Less than or equal
  bool operator <=(Date other) => isSameOrBefore(other);
 
  @override
@@ -374,4 +427,44 @@ class Date {
  day: day ?? this.day,
  );
  }
+
+ /// Convenient method to [DateFormat]
+ String format([String pattern = 'yMd', String? locale]) {
+ return DateFormat(pattern, locale).format(asDateTime);
+ }
+
+ /// Return enum value of day of week
+ DAY get getDAY => DAY.fromNumber(weekday);
+
+ /// Return a non iso [Week] object for this date
+ Week get week => Week.week(this);
+
+ /// Return the iso [Week] object for this date
+ Week get isoWeek => Week.isoWeek(this);
+
+ /// Return the [Month] object for this date.
+ Month get getMonth => Month.fromDate(this);
+
+ /// Get the enum value of month
+ MONTH get getMONTH => MONTH.fromNumber(month);
+
+ /// Return the [Year] object for this date.
+ Year get getYear => Year.fromDate(this);
+
+ /// Const value to signify the start of epoch that can be used as a default value
+ static const Date epoch = Date(year: 1970);
+
+ /// Const value to signify the start of time that can be used as a default value
+ static const Date startOfTime = Date(year: 1);
+
+ /// Const value to signify the end of time that can be used as a default value
+ static const Date endOfTime = Date(year: 9999, month: 12, day: 31);
+
+ ///////////////////////////////////// KEY
+
+ /// Convert [Date] to a unique id
+ String get key => format('yyyy-MM-dd');
+
+ /// Convert a unique id to [Date]
+ static Date? fromKey(String key) => tryParse(key, format: 'yyyy-MM-dd');
 }

lib/src/date_time_range.dart

@@ -0,0 +1,62 @@
+import 'package:date_time/src/extensions.dart';
+
+///
+class DateTimeRange {
+ ///
+ DateTimeRange({
+ required this.start,
+ required this.end,
+ }) : assert(!start.isAfter(end));
+
+ ///
+ final DateTime start;
+
+ ///
+ final DateTime end;
+
+ ///
+ bool get isValid => start <= end;
+
+ ///
+ Duration get duration => end.difference(start);
+
+ @override
+ bool operator ==(Object other) =>
+ other is DateTimeRange && other.start == start && other.end == end;
+
+ @override
+ int get hashCode => Object.hash(start, end);
+
+ @override
+ String toString() => '$start - $end';
+
+ ///
+ DateTimeRange expand(DateTime datetime) {
+ if (datetime.isBefore(start)) {
+ return copyWith(start: datetime);
+ } else if (datetime.isAfter(end)) {
+ return copyWith(end: datetime);
+ }
+ return this;
+ }
+
+ ///
+ DateTimeRange expandOther(DateTimeRange other) {
+ if (other.start.isBefore(start) && other.end.isAfter(end)) {
+ return copyWith(start: other.start, end: other.end);
+ } else if (other.start.isBefore(start)) {
+ return copyWith(start: other.start);
+ } else if (other.end.isAfter(end)) {
+ return copyWith(end: other.end);
+ }
+ return this;
+ }
+
+ ///
+ DateTimeRange copyWith({DateTime? start, DateTime? end}) {
+ return DateTimeRange(
+ start: start ?? this.start,
+ end: end ?? this.end,
+ );
+ }
+}