phantomknight287/aero

public

Update dependencies and enhance flight information model0844da02 years ago135 lines · 4.3 KB

1	import 'package:timezone/timezone.dart' as tz;
2	import 'package:timezone/data/latest.dart' as tz;
3	import 'package:intl/intl.dart';
4
5	/// Calculates the duration between two dates in different timezones
6	///
7	/// Parameters:
8	/// - date1: First date string (supports multiple formats including ISO 8601)
9	/// - timezone1: IANA timezone for first date
10	/// - date2: Second date string
11	/// - timezone2: IANA timezone for second date
12	/// - format: Optional custom format for non-ISO dates
13	Duration calculateTimezoneDifference({
14	required String date1,
15	required String timezone1,
16	required String date2,
17	required String timezone2,
18	String? format,
19	}) {
20	// Initialize timezone database
21	try {
22	tz.initializeTimeZones();
23	} catch (e) {
24	throw TimeZoneInitException('Failed to initialize timezone database: $e
25	}
26
27	try {
28	// Parse dates using appropriate method
29	final parsedDate1 = _parseDateTime(date1
30	final parsedDate2 = _parseDateTime(date2
31
32	// Get timezone locations
33	final location1 = tz.getLocation
34	final location2 = tz.getLocation
35
36	// Convert to TZDateTime for each timezone
37	final tzDateTime1 = tz.TZDateTime
38	final tzDateTime2 = tz.TZDateTime
39
40	// Calculate difference
41	return tzDateTime2.difference(tzDateTime1);
42	} on tz.LocationNotFoundException catch (e) {
43	throw TimeZoneNotFoundException('Invalid timezone identifier: $e
44	} catch (e) {
45	throw Exception('Error calculating timezone difference: $e
46	}
47	}
48
49	/// Helper function to parse datetime strings in various formats
50	DateTime _parseDateTime(String dateStr
51	try {
52	// First try parsing as ISO 8601
53	return DateTime.parse
54	} catch (_) {
55	// If ISO parsing fails and format is provided, try using the format
56	if (format != null) {
57	try {
58	return DateFormat(format).parse
59	} catch (e) {
60	throw DateParseException('Could not parse "$dateStr
61	'Error: $e');
62	}
63	}
64
65	// If no format provided, try common formats
66	final commonFormats = [
67	"yyyy-MM-dd HH:mm",
68	"yyyy-MM-dd hh:mm a",
69	"MM/dd/yyyy HH:mm",
70	"dd-MM-yyyy HH:mm",
71	"yyyy/MM/dd HH:mm",
72	];
73
74	for (final fmt in commonFormats) {
75	try {
76	return DateFormat(fmt).parse
77	} catch (_) {
78	continue;
79	}
80	}
81
82	throw DateParseException('Could not parse "$dateStr
83	'or specify a custom format.');
84	}
85	}
86
87	/// Custom exception classes (same as before)
88	class DateParseException implements Exception
89	final String message;
90	DateParseException(this.message);
91
92	@override
93	String toString() => message
94	}
95
96	class TimeZoneInitException implements Exception
97	final String message;
98	TimeZoneInitException(this.message);
99
100	@override
101	String toString() => message
102	}
103
104	class TimeZoneNotFoundException implements Exception
105	final String message;
106	TimeZoneNotFoundException(this.message);
107
108	@override
109	String toString() => message
110	}
111
112	// Example usage with different date formats
113	void main() {
114	try {
115	// Example 1: Using ISO 8601 format
116	final duration1 = calculateTimezoneDifference(date1
117	print('Duration 1: ${duration1.
118
119	// Example 2: Using custom format
120	final duration2 = calculateTimezoneDifference(date1
121	print('Duration 2: ${duration2.
122
123	// Example 3: Using common format without specifying format string
124	final duration3 = calculateTimezoneDifference(date1
125	print('Duration 3: ${duration3.
126	} on DateParseException catch (e) {
127	print('Date parsing error: $e'
128	} on TimeZoneNotFoundException catch (e) {
129	print('Timezone error: $e'
130	} on TimeZoneInitException catch (e) {
131	print('Initialization error: $e'
132	} catch (e) {
133	print('Unexpected error: $e'
134	}
135	}