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

#[derive(Clone, Copy, Debug, PartialEq, Eq)]
pub enum DurationKind {
    Quarter,
    Half,
    Whole,
}

#[derive(Clone, Copy, Debug, PartialEq, Eq)]
pub struct Duration {
    pub kind: DurationKind,
    pub is_dotted: bool,
}

impl Duration {
    pub fn new(kind: DurationKind, is_dotted: bool) -> Self {
        Self { kind, is_dotted }
    }

    pub fn beats(self, unit: u8) -> f64 {
        let mut n = match self.kind {
            DurationKind::Quarter => 4.,
            DurationKind::Half => 2.,
            DurationKind::Whole => 1.,
        };
        if self.is_dotted {
            n *= 1.5;
        }

        unit as f64 / n
    }
}