salah 0.7.6

Islamic prayer time library for Rust
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70

// Salah
//
// See LICENSE for more details.
// Copyright (c) 2019-2022 Farhan Ahmed. All rights reserved.
//

use crate::astronomy::unit::Coordinates;

/// Rule for approximating Fajr and Isha at high latitudes
#[derive(PartialEq, Debug, Copy, Clone)]
pub enum HighLatitudeRule {
    /// Fajr won't be earlier than the midpoint of the night and isha
    /// won't be later than the midpoint of the night. This is the default
    /// value to prevent fajr and isha crossing boundaries.
    MiddleOfTheNight,

    /// Fajr will never be earlier than the beginning of the last seventh of
    /// the night and Isha will never be later than the end of the first seventh of the night.
    ///
    /// This is recommended to use for locations above 48° latitude to prevent prayer
    /// times that would be difficult to perform.
    SeventhOfTheNight,

    /// The night is divided into portions of roughly 1/3. The exact value is derived
    /// by dividing the fajr/isha angles by 60.
    ///
    /// This can be used to prevent difficult fajr and isha times at certain locations.
    TwilightAngle,
}

impl HighLatitudeRule {
    pub fn recommended(coordinates: Coordinates) -> HighLatitudeRule {
        if coordinates.latitude > 48.0 {
            HighLatitudeRule::SeventhOfTheNight
        } else {
            HighLatitudeRule::MiddleOfTheNight
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn recommended_rule_seventh_of_night() {
        let location = Coordinates {
            latitude: 48.983226,
            longitude: -3.216649,
        };

        assert_eq!(
            HighLatitudeRule::recommended(location),
            HighLatitudeRule::SeventhOfTheNight
        );
    }

    #[test]
    fn recommended_rule_middle_of_night() {
        let location = Coordinates {
            latitude: 45.983226,
            longitude: -3.216649,
        };

        assert_eq!(
            HighLatitudeRule::recommended(location),
            HighLatitudeRule::MiddleOfTheNight
        );
    }
}