use anyhow::{bail, Error, Result};
use std::{
    io::{BufRead, BufReader},
    str::FromStr,
    time::Duration,
};

#[derive(Debug)]
enum Speed {
    Slow,
    Fast,
    Inst,
}

impl FromStr for Speed {
    type Err = Error;

    fn from_str(s: &str) -> Result<Self> {
        match s {
            "SLOW" => Ok(Self::Slow),
            "FAST" => Ok(Self::Fast),
            "INST" => Ok(Self::Inst),
            _ => bail!("Could not parse speed"),
        }
    }
}

fn parse(input: &str) -> Result<(usize, usize, f32, Speed)> {
    let input = input
        .replace("CPS, ", "")
        .replace(", CPM, ", " ")
        .replace(", uSv/hr, ", " ")
        .replace(", ", " ");
    let input: Vec<&str> = input.split(' ').collect();

    Ok((
        input[0].parse::<usize>()?,
        input[1].parse::<usize>()?,
        input[2].parse::<f32>()?,
        input[3].parse::<Speed>()?,
    ))
}

fn main() -> Result<()> {
    let port_name = "/dev/serial0";
    let baud_rate = 9600;

    let port = serialport::new(port_name, baud_rate)
        .timeout(Duration::from_millis(1000))
        .open()?;

    let mut port = BufReader::new(port);
    loop {
        let mut line = String::new();
        port.read_line(&mut line)?;
        println!("{:?}", line);
        println!("{:?}", parse(line.trim())?);
    }
}