use axum::{
    extract::Query,
    routing::get,
    Router,
};
use serde::Deserialize;

#[derive(Deserialize)]
struct ProbeClientToServerQuery {
    domain: String,
    hostname: String,
    port: u16,
}


#[tokio::main]
async fn main() {

    let mut args = std::env::args();
    let _name = args.next().unwrap();

    let mut listen = String::from("[::]:3000");

    loop {
        let arg = if let Some(arg) = args.next() {
            arg
        } else {
            break;
        };

        match arg.as_str() {
            "--listen" => {
                listen = args.next().unwrap();
            }
            unknown => {
                println!("unknown option: {}", unknown);
                std::process::exit(1)
            }
        }
    }

    let app = Router::new()
        .route("/", get(route_index))
        .route("/probe-client-to-server", get(route_probe_client_to_server));

    let listener = tokio::net::TcpListener::bind(listen).await.unwrap();
    println!("Server listening on: http://{}", listener.local_addr().unwrap());
    println!("Probe with:");
    println!("  http://{}/probe-client-to-server?domain=fem-net.de&hostname=xmpp-2.net.clerie.de&port=5222", listener.local_addr().unwrap());

    axum::serve(listener, app).await.unwrap();
}

async fn route_index() -> String {
    return String::from("Prometheus exporter for checking XMPP server availability");
}

async fn route_probe_client_to_server(
    Query(query): Query<ProbeClientToServerQuery>,
) -> Result<String, String> {
    let mut out = String::new();
    out.push_str(&format!("{} {}:{}", query.domain, query.hostname, query.port));

    return Ok(out);
}