use std::ops::Range;

pub trait ECoreSelector {
    fn next_core(&mut self) -> i32;
}

//TODO: better core selection e.g. try to keep task on the same core
pub struct RoundRobinSelector {
    offset: u32,
    num_cores: u32,
    last_used: u32
}

impl RoundRobinSelector {
    pub fn new(e_cores: Range<u32>) -> RoundRobinSelector {
        Self {
            offset: e_cores.start,
            num_cores: e_cores.len() as u32,
            last_used: 0,
        }
    }
}

impl ECoreSelector for RoundRobinSelector {
    fn next_core(&mut self) -> i32 {
        self.last_used += 1;
        (self.offset + (self.last_used % self.num_cores)) as i32
    }
}