/// <summary>
/// Adjust calculated imsak, fajr, maghrib and isha prayer times to high latitude adjustment.
/// </summary>
private static PrayersInDouble AdjustAllForHighLatitude(PrayersInDouble raw, PrayerCalculationSettings settings)
{
//
// Do not apply adjustment if none option is specified.
if (settings.HighLatitudeAdjustment == HighLatitudeAdjustment.None)
{
return(raw);
}
// Copy reference.
var method = settings.HighLatitudeAdjustment;
var imsak = raw.Imsak;
var fajr = raw.Fajr;
var sunrise = raw.Sunrise;
var sunset = raw.Sunset;
var maghrib = raw.Maghrib;
var isha = raw.Isha;
var imsakParameterValue = settings.ImsakParameter.Value;
var fajrParameterValue = settings.CalculationMethod.FajrParameter.Value;
var maghribParameterValue = settings.CalculationMethod.MaghribParameter.Value;
var ishaParameterValue = settings.CalculationMethod.IshaParameter.Value;
// Compute sunrise to sunset difference.
var diff = DateTimeMath.ComputeDuration(raw.Sunrise, raw.Sunset);
// Adjust.
raw.Imsak = AdjustForHighLatitude(method, imsak, sunrise, imsakParameterValue, diff, Direction.CounterClockwise);
raw.Fajr = AdjustForHighLatitude(method, fajr, sunrise, fajrParameterValue, diff, Direction.CounterClockwise);
raw.Maghrib = AdjustForHighLatitude(method, maghrib, sunset, maghribParameterValue, diff, Direction.Clockwise);
raw.Isha = AdjustForHighLatitude(method, isha, sunset, ishaParameterValue, diff, Direction.Clockwise);
return(raw);
}
/// <summary>
/// Apply adjustments to given calculated prayer time.
/// </summary>
private static PrayersInDouble AdjustTime(PrayersInDouble raw, PrayerCalculationSettings settings, double longitude, double timeZone)
{
// Adjust imsak if minute adjustment parameter is used.
if (settings.ImsakParameter.Type == PrayerCalculationParameterType.MinutesAdjust)
{
raw.Imsak = raw.Fajr + (settings.ImsakParameter.Value / 60.0);
}
// Adjust maghrib if minute adjustment parameter is used.
// This is Sunni method which maghrib equals to sunset. As precaution, this
// library add 1 minute to the sunset time.
if (settings.CalculationMethod.MaghribParameter.Type == PrayerCalculationParameterType.MinutesAdjust)
{
raw.Maghrib = raw.Sunset + 0.016666666666666667 + (settings.CalculationMethod.MaghribParameter.Value / 60.0);
}
// Adjust isha if minute adjustment parameter is used.
if (settings.CalculationMethod.IshaParameter.Type == PrayerCalculationParameterType.MinutesAdjust)
{
raw.Isha = raw.Maghrib + (settings.CalculationMethod.IshaParameter.Value / 60.0);
}
// Adjust to time zone.
raw = AdjustAllToTimeZone(raw, longitude, timeZone);
raw = AdjustAllForHighLatitude(raw, settings);
raw = MinuteAdjustAll(raw, settings);
return(raw);
}
/// <summary>
/// Apply time zone adjustment to given calculated prayer time.
/// </summary>
private static PrayersInDouble MinuteAdjustAll(PrayersInDouble raw, PrayerCalculationSettings settings)
{
raw.Imsak = raw.Imsak + (settings.ImsakMinutesAdjustment / 60.0);
raw.Fajr = raw.Fajr + (settings.FajrMinutesAdjustment / 60.0);
raw.Sunrise = raw.Sunrise + (settings.SunriseMinutesAdjustment / 60.0);
raw.Dhuha = raw.Dhuha + (settings.DhuhaMinutesAdjustment / 60.0);
raw.Zuhr = raw.Zuhr + (settings.ZuhrMinutesAdjustment / 60.0);
raw.Asr = raw.Asr + (settings.AsrMinutesAdjustment / 60.0);
raw.Maghrib = raw.Maghrib + (settings.MaghribMinutesAdjustment / 60.0);
raw.Isha = raw.Isha + (settings.IshaMinutesAdjustment / 60.0);
return(raw);
}
/// <summary>
/// Generate after later prayer time.
/// </summary>
/// <param name="clock">
/// <see cref="IClock" /> interface object for getting after later <see cref="Instant" /> value.
/// </param>
/// <param name="settings">
/// Settings containing parameters for calculating prayer times.
/// </param>
/// <param name="coordinate">
/// Location's coordinate.
/// </param>
/// <param name="timeZone">
/// Location's time zone.
/// </param>
/// <returns>
/// <see cref="Prayer" /> object containing after later prayer time data.
/// </returns>
internal static Prayer GetAfterLaterPrayerTime(IClock clock, PrayerCalculationSettings settings, Geocoordinate coordinate, double timeZone)
{
var now = clock.GetCurrentInstant();
var today = GetPrayerTimesForOneDay(now, settings, coordinate, timeZone);
var tomorrow = GetPrayerTimesForOneDay(now + Duration.FromDays(1), settings, coordinate, timeZone);
if (now < today.Imsak)
{
return(new Prayer(PrayerType.Sunrise, today.Sunrise));
}
if (now < today.Fajr)
{
return(new Prayer(PrayerType.Dhuha, today.Dhuha));
}
if (now < today.Sunrise)
{
return(new Prayer(PrayerType.Zuhr, today.Zuhr));
}
if (now < today.Dhuha)
{
return(new Prayer(PrayerType.Asr, today.Asr));
}
if (now < today.Zuhr)
{
return(new Prayer(PrayerType.Maghrib, today.Maghrib));
}
if (now < today.Asr)
{
return(new Prayer(PrayerType.Isha, today.Isha));
}
if (now < today.Maghrib)
{
return(new Prayer(PrayerType.Imsak, today.Imsak));
}
if (now < today.Isha)
{
return(new Prayer(PrayerType.Fajr, tomorrow.Fajr));
}
return(new Prayer(PrayerType.Sunrise, tomorrow.Sunrise));
}
/// <summary>
/// Generate prayer times for one day at given date.
/// </summary>
/// <param name="when">
/// <see cref="Instant" /> value which represents the date.
/// </param>
/// <param name="settings">
/// Settings containing parameters for calculating prayer times.
/// </param>
/// <param name="coordinate">
/// Location's coordinate.
/// </param>
/// <param name="timeZone">
/// Location's time zone.
/// </param>
/// <returns>
/// <see cref="Prayers" /> object containing prayer times for one day at given date.
/// </returns>
internal static Prayers GetPrayerTimesForOneDay(Instant when, [NotNull] PrayerCalculationSettings settings, Geocoordinate coordinate, double timeZone)
{
if (settings == null)
{
throw new ArgumentNullException(nameof(settings));
}
var utc = when.InUtc();
var year = utc.Year;
var month = utc.Month;
var day = utc.Day;
var local = new LocalDate(year, month, day);
var newUtc = new ZonedDateTime(local.AtMidnight(), DateTimeZone.Utc, Offset.Zero);
var jd = newUtc.ToInstant().ToJulianDate() - (coordinate.Longitude / 360.0);
var raw = ComputeRaw(jd, settings, coordinate.Latitude, coordinate.Altitude);
var afterAdjustment = AdjustTime(raw, settings, coordinate.Longitude, timeZone);
// Calculate midnight.
var fajr = afterAdjustment.Fajr;
var sunrise = afterAdjustment.Sunrise;
var sunset = afterAdjustment.Sunset;
afterAdjustment.Midnight = ComputeMidnightTime(settings.CalculationMethod.MidnightMethod, fajr, sunrise, sunset);
// Convert.
var converted = ConvertFromFloatingPointFormat(afterAdjustment, year, month, day, timeZone);
// Round.
var rounded = new Prayers(RoundPrayerTime(converted.Imsak),
RoundPrayerTime(converted.Fajr),
RoundPrayerTime(converted.Sunrise),
RoundPrayerTime(converted.Dhuha),
RoundPrayerTime(converted.Zuhr),
RoundPrayerTime(converted.Asr),
RoundPrayerTime(converted.Sunset),
RoundPrayerTime(converted.Maghrib),
RoundPrayerTime(converted.Isha),
RoundPrayerTime(converted.Midnight));
return(rounded);
}
/// <summary>
/// Compute all prayer times at given Julian Date and return the raw results.
/// </summary>
private static PrayersInDouble ComputeRaw(double jd, PrayerCalculationSettings settings, double latitude, double altitude)
{
var raw = new PrayersInDouble();
// Compute imsak.
if (settings.ImsakParameter.Type == PrayerCalculationParameterType.Angle)
{
// raw.imsak = _computeImsakTime(jd, settings.imsakParameter.value, latitude);
// NOTE: Do imsak time can be calculated using angle parameter?
throw new PrayerCalculationException("Imsak calculation parameter type must be the type of minute adjust.");
}
// Check fajr parameter type.
if (settings.CalculationMethod.FajrParameter.Type == PrayerCalculationParameterType.MinutesAdjust)
{
throw new PrayerCalculationException("Fajr calculation parameter type must be the type of angle.");
}
// Compute fajr, sunrise, dhuha, zuhr, asr and sunset.
raw.Fajr = ComputeFajrTime(jd, settings.CalculationMethod.FajrParameter.Value, latitude);
raw.Sunrise = ComputeSunriseTime(jd, latitude, altitude);
raw.Dhuha = ComputeDhuhaTime(raw.Fajr, raw.Sunrise);
raw.Zuhr = ComputeZuhrTime(jd);
raw.Asr = ComputeAsrTime(jd, settings.JuristicMethod.TimeOfShadow, latitude);
raw.Sunset = ComputeSunsetTime(jd, latitude, altitude);
// Compute maghrib.
if (settings.CalculationMethod.MaghribParameter.Type == PrayerCalculationParameterType.Angle)
{
raw.Maghrib = ComputeMaghribTime(jd, settings.CalculationMethod.MaghribParameter.Value, latitude);
}
// Compute isha.
if (settings.CalculationMethod.IshaParameter.Type == PrayerCalculationParameterType.Angle)
{
raw.Isha = ComputeIshaTime(jd, settings.CalculationMethod.IshaParameter.Value, latitude);
}
return(raw);
}
/// <summary>
/// Get next prayer time.
/// </summary>
/// <param name="settings">
/// Settings containing parameters for calculating prayer times.
/// </param>
/// <param name="coordinate">
/// Location's coordinate.
/// </param>
/// <param name="timeZone">
/// Location's time zone.
/// </param>
/// <param name="clock">
/// <see cref="IClock" /> interface object for getting current <see cref="Instant" /> value.
/// </param>
/// <returns>
/// <see cref="Prayer" /> object containing next prayer time data.
/// </returns>
public static Prayer Next(PrayerCalculationSettings settings, Geocoordinate coordinate, double timeZone, IClock clock)
{
return(PrayerCalculator.GetNextPrayerTime(clock, settings, coordinate, timeZone));
}
/// <summary>
/// Get prayer times for given date.
/// </summary>
/// <param name="when">
/// <see cref="Instant" /> value which represents the date.
/// </param>
/// <param name="settings">
/// Settings containing parameters for calculating prayer times.
/// </param>
/// <param name="coordinate">
/// Location's coordinate.
/// </param>
/// <param name="timeZone">
/// Location's time zone.
/// </param>
/// <returns>
/// <see cref="Prayers" /> object containing prayer times for given date.
/// </returns>
public static Prayers On(Instant when, PrayerCalculationSettings settings, Geocoordinate coordinate, double timeZone)
{
return(PrayerCalculator.GetPrayerTimesForOneDay(when, settings, coordinate, timeZone));
}
/// <summary>
/// Get prayer times for today.
/// </summary>
/// <param name="settings">
/// Settings containing parameters for calculating prayer times.
/// </param>
/// <param name="coordinate">
/// Location's coordinate.
/// </param>
/// <param name="timeZone">
/// Location's time zone.
/// </param>
/// <param name="clock">
/// <see cref="IClock" /> interface object for getting current <see cref="Instant" /> value.
/// </param>
/// <returns>
/// <see cref="Prayers" /> object containing prayer times for today.
/// </returns>
public static Prayers Today(PrayerCalculationSettings settings, Geocoordinate coordinate, double timeZone, IClock clock)
{
var now = clock.GetCurrentInstant();
return(PrayerCalculator.GetPrayerTimesForOneDay(now, settings, coordinate, timeZone));
}