pub struct DelayLine<const LEN: usize> {
    buffer: [f32; LEN],
    index: usize,
}

impl<const LEN: usize> DelayLine<LEN> {
    pub fn new() -> Self {
        Self {
            buffer: [0.0; LEN],
            index: 0,
        }
    }

    pub fn read_slice(&self, slice: &mut [f32]) {
        // Copy values in order
        for i in 0..LEN {
            slice[i] = self.buffer[(self.index + i - LEN) % LEN];
        }
    }

    pub fn write_and_advance(&mut self, value: f32) {
        self.buffer[self.index] = value;

        if self.index == LEN - 1 {
            self.index = 0;
        } else {
            self.index += 1;
        }
    }
}