use std::str::FromStr;

extern crate hptp;

#[derive(Debug)]
struct Hostname {
    ip: String,
    port: u16,
}

struct InvalidHostnameError;

impl FromStr for Hostname {
    type Err = InvalidHostnameError;
    fn from_str(s: &str) -> Result<Self, Self::Err> {
        let i = s.find(':').ok_or(InvalidHostnameError)?;
        Ok(Hostname {
            ip: s[..i].into(),
            port: s[i + 1..].parse().map_err(|_| InvalidHostnameError)?,
        })
    }
}

fn usage() {
    print!("usage:\n./3700send <host-ip>:<host-port>\n")
}

fn parse_args() -> Result<Hostname, ()> {
    std::env::args().nth(1).ok_or(())?.parse().map_err(|_| ())
}

fn main() {
    match parse_args() {
        Ok(x) => start(x),
        Err(_) => usage(),
    }
}

fn start(hn: Hostname) {
    println!("ip={}, port={}", hn.ip, hn.port)
}