use wgcloak::config::{Config, ServerConfig, MAX_APPLICATION_DATAGRAM_SIZE};

const SECRET: &str = "MDEyMzQ1Njc4OWFiY2RlZjAxMjM0NTY3ODlhYmNkZWY=";

fn server_text(max_datagram_size: Option<u16>) -> String {
    let network = max_datagram_size
        .map(|value| format!("[network]\nmax_datagram_size = {value}\n"))
        .unwrap_or_default();
    format!(
        "[server]\nlisten = \"::1\"\n[backend]\ntarget = \"127.0.0.1:51820\"\n{network}[transports.direct_udp]\nport = 51830\n[[auth.clients]]\nid = \"test\"\nsecret = \"{SECRET}\"\n"
    )
}

#[test]
fn server_datagram_capability_defaults_and_accepts_boundary() {
    let Config::Server(defaults) = Config::from_str(&server_text(None)).unwrap() else {
        panic!("expected server configuration");
    };
    assert_eq!(defaults.network.max_datagram_size, 1200);

    let Config::Server(config) =
        Config::from_str(&server_text(Some(MAX_APPLICATION_DATAGRAM_SIZE))).unwrap()
    else {
        panic!("expected server configuration");
    };
    config.validate().unwrap();
    assert_eq!(
        config.network.max_datagram_size,
        MAX_APPLICATION_DATAGRAM_SIZE
    );
}

#[test]
fn server_datagram_capability_rejects_unsupported_size() {
    let Config::Server(config) =
        Config::from_str(&server_text(Some(MAX_APPLICATION_DATAGRAM_SIZE + 1))).unwrap()
    else {
        panic!("expected server configuration");
    };
    let error = config.validate().unwrap_err().to_string();
    assert!(error.contains("network.max_datagram_size"));
}

#[test]
fn server_config_type_remains_constructible_from_toml() {
    let Config::Server(config): Config = Config::from_str(&server_text(Some(1400))).unwrap() else {
        panic!("expected server configuration");
    };
    let _: ServerConfig = config;
}