use crate::filter::Filter;
use crate::window_buffer::WindowBuffer;
use crate::{config, measurement, Error};
pub struct Sum<T> {
window_buffer: WindowBuffer<Option<T>>,
}
impl<T> TryFrom<&config::FilterSum> for Sum<T>
where
T: Default + Copy,
{
type Error = Error;
fn try_from(sum: &config::FilterSum) -> std::result::Result<Self, Self::Error> {
Ok(Self {
window_buffer: WindowBuffer::try_from(&sum.window_config)?,
})
}
}
impl<T> Filter<T> for Sum<T>
where
T: Send + Sync + Copy + measurement::Measurement,
T: std::ops::Add<Output = T> + std::iter::Sum,
{
fn filter(&mut self, data: T) -> T {
self.window_buffer.push(Some(data));
self.window_buffer.iter().filter_map(|x| *x).sum()
}
fn error(&mut self) {
self.window_buffer.push(None);
}
}
#[cfg(test)]
mod test {
use super::*;
fn size(size: u64) -> measurement::DataSize {
use measurement::Measurement;
measurement::DataSize::new(size).unwrap()
}
#[tokio::test]
async fn test_sum_filter() {
let mut filter = Sum::<measurement::DataSize>::try_from(&config::FilterSum {
window_config: config::FilterWindowConfig { window_size: 3 },
})
.unwrap();
assert_eq!(filter.filter(size(1)), size(1)); assert_eq!(filter.filter(size(2)), size(3));
assert_eq!(filter.filter(size(3)), size(6));
assert_eq!(filter.filter(size(4)), size(9)); filter.error(); assert_eq!(filter.filter(size(5)), size(9)); filter.error(); assert_eq!(filter.filter(size(0)), size(5));
assert_eq!(filter.filter(size(0)), size(0)); }
}