Date_Time

Date and Time

Conversion to UTC

Converting from one timezone to UTC timezone.

/// Convert user timezone to UTC
public static func dateTimeToUTC(_ date: Date,
								 timezone: TimeZone) -> Date {
	print("Current date passed \(date)")
	// First convert Device time zone into User saved timezone
	let userProfileRegion = Region(calendar: date.calendar, zone: timezone)
	// Generate date components from user profile date for year, month, day
	let components = DateInRegion(date, region: userProfileRegion).dateComponents
	// Confirm date contained valid components
	guard let year = components.year,
		  let month = components.month,
		  let day = components.day else { return date }
	print("Conversion USer PRofile TimeZone to UTC")
	print(components)
	
	let userProfileRegion2 = Region(calendar: date.calendar, zone: Calendar.current.timeZone)
	let defaultComponents = DateInRegion(Date(), region: userProfileRegion2).dateComponents
	// Confirm date contained valid components
	guard let hour = defaultComponents.hour,
		  let minute = defaultComponents.minute else { return date }
	
	print(" printing components \(hour) \(minute)" )
	
	// Translate user profile date back into UTC date, keeping year, month, day
	let newRegion = Region(calendar: date.calendar, zone: Calendar.current.timeZone)
	
	let dateTestDummy = Date(year: year,
							 month: month,
							 day: day,
							 hour: hour,
							 minute: minute,
							 region: newRegion)
	
	print("Printing TestDummy with region diff")
	print(dateTestDummy)
	let dateDummy2 = Calendar.current.dateComponents(in: TimeZone(secondsFromGMT: 0)!, from: dateTestDummy)
	print(" Printing direct conversion \(dateDummy2)"  )
	return dateTestDummy
}

public static func dateFromUTCToUserProfileTimezone(_ date: Date,
												  timezone: TimeZone) -> Date {
	
	let convertedString = DateUtils.string(date, timezone: timezone)
	print("Converting date string \(convertedString)")
	
	let secondsFromGMT = timezone.secondsFromGMT()
	print("seconds from GMT \(secondsFromGMT)")
	let userTZDateComponents = Calendar.current.dateComponents(in: TimeZone(secondsFromGMT: secondsFromGMT)!, from: date)
	print("Converted date components UTC to user timezone")
	print(userTZDateComponents)
	
	// Confirm date contained valid components
	guard let year = userTZDateComponents.year,
		  let month = userTZDateComponents.month,
		  let day = userTZDateComponents.day,
		  let hour = userTZDateComponents.hour,
		  let minute = userTZDateComponents.minute else { return date }
	print(day)
	print(hour)
	let dateTestDummy = Date(year: year,
				month: month,
				day: day,
				hour: hour,
				minute: minute)
	print("Converted Date components into Date Object")
	print(dateTestDummy)
	return dateTestDummy
}

Time

Mutating time object so that you can work around certain scenarios about it.

// Checking for custom refreshToken override

var customExpirationDate: Date?

if let storedExpiredToken = UserDefaults.standard.value(forKey: UserDefaults.Keys.customRefreshTokenValue) {
	print("Value was found")
	if let retrievedDate = storedExpiredToken as? Date {
		customExpirationDate = retrievedDate
	}
} else {
	// Assuming the user has logged in - which is correct since `Mission Control`
	// setupRefreshTokenExpirationBindings checks if auth object is present and then .unwraps()
	// it which makes sure that auth object is present in order to override the expirationDate() in User Defaults.
	customExpirationDate = Date().addingTimeInterval(60)
	UserDefaults.standard.set(customExpirationDate, forKey: UserDefaults.Keys.customRefreshTokenValue)
}

Date range ... operator to define a Range(startDate...endDate)

let easementDate = expirationDate.addingTimeInterval(Constant.easementTimeInternal)
let easementWindow = easementDate...expirationDate
print(easementWindow)
print("Easement window range \(easementWindow.contains(Date()))")

Check whether the date is way past current date.

let isCustomDateExpiredCheck = Date().isAfterDate(expirationDate, granularity: .minute)
print("My custom Expiration check: \(isCustomDateExpiredCheck)")

Formatting

Formatting time interval in swift using build in DateComponentsFormatter()
& TimeInterval.

cocoa-fundamentals-formatting-a-time-interval-in-swift

Formatting UTC Date

Timezone Help

Also you can have Clock in your local timezone and UTC as mac os widgets or phone widgets.

Just adopt the ISO 8601 format for Date Time

Converter to not kill yourself

Different Timezone abbreviations

Swift ISO date creation

CMTime

Code

var videoStartTime: CMTime = CMTimeMake(value: 10, timescale: 1)

It is fractional so 10/1 = 10 secs
These two values are a fraction. The value is the numerator, and timescale is the denominator.

Time precision with Floats and new struct type needed
understanding-cmtime

cmtime-for-human-beings

coremedia cmtime-u58 documentation apple

swiftui | handbook-controls-with-avplayer

References

Convert String to Date

convert string to date cocoacasts

swift-date

CMTime