Merge pull request #7 from insha/insha-issue-6-wrong-prayer-times

Fixing the issue with the wrong prayer times

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "salah"
-version = "0.4.2"
+version = "0.5.0"
 authors = ["Farhan Ahmed <[email protected]>"]
 edition = "2018"
 description = "Islamic prayer time library for Rust"

README.md

@@ -15,7 +15,7 @@ Add the following to your `Cargo.toml` file under the `[dependencies]` section:
 
 ```
 [dependencies]
-salah = "0.4.2"
+salah = "0.5.0"
 ```
 
 To get prayer times, use the `PrayerSchedule` struct passing in coordinates, date, and calculation parameters.

src/astronomy/qiblah.rs

@@ -120,4 +120,12 @@ mod tests {
 
         assert_eq!(qiblah.0, 293.02072441441163);
     }
+
+    #[test]
+    fn qiblah_direction_from_jakarta_indonesia() {
+        let jakarta = Coordinates::new(-6.18233995, 106.84287154);
+        let qiblah = Qiblah::new(jakarta);
+
+        assert_that!(qiblah.0).is_close_to(295.1442983825265, 0.0000001f64);
+    }
 }

src/astronomy/solar.rs

@@ -194,14 +194,8 @@ impl SolarTime {
             let calculated_seconds =
                 ((value - (calculated_hours + calculated_minutes / 60.0)) * 60.0 * 60.0).floor();
 
-            // Adjust the hour to be within 0..=23,
-            // wrapping around as needed; otherwise
-            // chrono method will panic.
-            let (adjusted_hour, adjusted_date) = if calculated_hours >= 24.0 {
-                ((calculated_hours - 24.0) as u32, date.tomorrow())
-            } else {
-                (calculated_hours as u32, date.clone())
-            };
+            let (adjusted_hour, adjusted_date) =
+                SolarTime::hour_adjustment(calculated_hours, &date);
 
             // Round to the nearest minute
             let adjusted_mins = (calculated_minutes + calculated_seconds / 60.0).round() as u32;
@@ -222,6 +216,19 @@ impl SolarTime {
 
         adjusted_time
     }
+
+    fn hour_adjustment(calculated_hours: f64, date: &DateTime<Utc>) -> (u32, DateTime<Utc>) {
+        // Adjust the hour to be within 0..=23,
+        // wrapping around as needed; otherwise
+        // chrono method will panic.
+        if calculated_hours < 0.0 {
+            ((calculated_hours + 24.0) as u32, date.yesterday())
+        } else if calculated_hours >= 24.0 {
+            ((calculated_hours - 24.0) as u32, date.tomorrow())
+        } else {
+            (calculated_hours as u32, date.clone())
+        }
+    }
 }
 
 #[cfg(test)]

src/lib.rs

@@ -39,9 +39,9 @@ pub use chrono::{Date, DateTime, Datelike, Duration, Local, TimeZone, Timelike,
 /// A convenience module appropriate for glob imports (`use salah::prelude::*;`).
 pub mod prelude {
     #[doc(no_inline)]
-    pub use crate::astronomy::unit::{Coordinates, Stride};
+    pub use crate::astronomy::qiblah::Qiblah;
     #[doc(no_inline)]
-	pub use crate::astronomy::qiblah::Qiblah;
+    pub use crate::astronomy::unit::{Coordinates, Stride};
     #[doc(no_inline)]
     pub use crate::models::adjustments::{Adjustment, TimeAdjustment};
     #[doc(no_inline)]
@@ -61,6 +61,8 @@ pub mod prelude {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use crate::models::high_altitude_rule::HighLatitudeRule;
+    use chrono::prelude::*;
 
     #[test]
     fn calculate_prayer_times() {
@@ -168,7 +170,6 @@ mod tests {
     #[test]
     fn calculate_qiyam_times() {
         let date = Utc.ymd(2015, 7, 12);
-        // let qiyam_date  = Utc.ymd(2015, 7, 13);
         let params = Configuration::with(Method::NorthAmerica, Madhab::Hanafi);
         let coordinates = Coordinates::new(35.7750, -78.6336);
         let result = PrayerSchedule::new()
@@ -198,4 +199,100 @@ mod tests {
             Err(_err) => assert!(false),
         }
     }
+
+    #[test]
+    fn calculate_times_for_singapore() {
+        let mut params = Configuration::with(Method::Singapore, Madhab::Shafi);
+
+        params.high_latitude_rule = HighLatitudeRule::MiddleOfTheNight;
+
+        // The adjustment below are based on the prayer times that are provided
+        // on the website (http://www.muis.gov.sg). I don't know the exact
+        // calculation that this site is using for the prayer times; therefore the
+        // use of time adjustment. However, these are within the 2 minute variance.
+        params.method_adjustments = Adjustment::new()
+            .fajr(1)
+            .sunrise(1)
+            .dhuhr(2)
+            .asr(1)
+            .maghrib(1)
+            .isha(1)
+            .done();
+
+        let result = PrayerSchedule::new()
+            .on(Utc.ymd(2021, 1, 13))
+            .for_location(Coordinates::new(1.370844612058886, 103.80145644060552))
+            .with_configuration(params)
+            .calculate();
+
+        match result {
+            Ok(schedule) => {
+                let hour = 3600;
+                let sgt_offset = FixedOffset::east(8 * hour);
+                let sgt_fajr = schedule.time(Prayer::Fajr).with_timezone(&sgt_offset);
+                let sgt_sunrise = schedule.time(Prayer::Sunrise).with_timezone(&sgt_offset);
+                let sgt_dhuhr = schedule.time(Prayer::Dhuhr).with_timezone(&sgt_offset);
+                let sgt_asr = schedule.time(Prayer::Asr).with_timezone(&sgt_offset);
+                let sgt_maghrib = schedule.time(Prayer::Maghrib).with_timezone(&sgt_offset);
+                let sgt_isha = schedule.time(Prayer::Isha).with_timezone(&sgt_offset);
+
+                assert_eq!(sgt_fajr.format("%-l:%M %p").to_string(), "5:50 AM");
+                assert_eq!(sgt_sunrise.format("%-l:%M %p").to_string(), "7:13 AM");
+                assert_eq!(sgt_dhuhr.format("%-l:%M %p").to_string(), "1:15 PM");
+                assert_eq!(sgt_asr.format("%-l:%M %p").to_string(), "4:39 PM");
+                assert_eq!(sgt_maghrib.format("%-l:%M %p").to_string(), "7:16 PM");
+                assert_eq!(sgt_isha.format("%-l:%M %p").to_string(), "8:30 PM");
+            }
+            Err(_err) => assert!(false),
+        }
+    }
+
+    #[test]
+    fn calculate_times_for_jakarta() {
+        let mut params = Configuration::with(Method::Egyptian, Madhab::Shafi);
+
+        // The adjustment below are based on the prayer times that are provided
+        // on the website (https://www.jadwalsholat.org/). I don't know the exact
+        // calculation that this site is using for the prayer times; therefore the
+        // use of time adjustment.
+        //
+        // It would be a good idea to get some more information on how the Fajr
+        // and Isha are calculated, since that's where the biggest variance is;
+        // however, the other times are within the 2 minute variance.
+        params.method_adjustments = Adjustment::new()
+            .fajr(-10)
+            .sunrise(-2)
+            .dhuhr(2)
+            .asr(1)
+            .maghrib(2)
+            .isha(4)
+            .done();
+
+        let result = PrayerSchedule::new()
+            .on(Utc.ymd(2021, 1, 12))
+            .for_location(Coordinates::new(-6.18233995, 106.84287154))
+            .with_configuration(params)
+            .calculate();
+
+        match result {
+            Ok(schedule) => {
+                let hour = 3600;
+                let wib_offset = FixedOffset::east(7 * hour);
+                let wib_fajr = schedule.time(Prayer::Fajr).with_timezone(&wib_offset);
+                let wib_sunrise = schedule.time(Prayer::Sunrise).with_timezone(&wib_offset);
+                let wib_dhuhr = schedule.time(Prayer::Dhuhr).with_timezone(&wib_offset);
+                let wib_asr = schedule.time(Prayer::Asr).with_timezone(&wib_offset);
+                let wib_maghrib = schedule.time(Prayer::Maghrib).with_timezone(&wib_offset);
+                let wib_isha = schedule.time(Prayer::Isha).with_timezone(&wib_offset);
+
+                assert_eq!(wib_fajr.format("%-l:%M %p").to_string(), "4:15 AM");
+                assert_eq!(wib_sunrise.format("%-l:%M %p").to_string(), "5:45 AM");
+                assert_eq!(wib_dhuhr.format("%-l:%M %p").to_string(), "12:03 PM");
+                assert_eq!(wib_asr.format("%-l:%M %p").to_string(), "3:28 PM");
+                assert_eq!(wib_maghrib.format("%-l:%M %p").to_string(), "6:16 PM");
+                assert_eq!(wib_isha.format("%-l:%M %p").to_string(), "7:31 PM");
+            }
+            Err(_err) => assert!(false),
+        }
+    }
 }