use clap::Parser;
use futures::stream::StreamExt;
use signal_hook::consts::signal;
use signal_hook_tokio::Signals;
use tokio::sync::oneshot;

use std::convert::Infallible;
use std::net::SocketAddr;
use std::path;
use std::str::FromStr;
use std::sync;

#[derive(Parser, Debug)]
#[command(version)]
#[command(about = "A domiply to another dimension")]
struct Cli {
    #[arg(long, default_value_t = SocketAddr::from_str("127.0.0.1:3030").unwrap(), env = "DOMIPLY_HTTP_LISTEN_ADDR")]
    http_listen_addr: SocketAddr,

    #[arg(long, required = true, env = "DOMIPLY_PASSPHRASE")]
    passphrase: String,

    #[arg(long, required = true, env = "DOMIPLY_ORIGIN_STORE_GIT_DIR_PATH")]
    origin_store_git_dir_path: path::PathBuf,

    #[arg(long, required = true, env = "DOMIPLY_DOMAIN_CHECKER_TARGET_CNAME")]
    domain_checker_target_cname: domiply::domain::Name,

    #[arg(long, default_value_t = String::from("1.1.1.1:53"), env = "DOMIPLY_DOMAIN_CHECKER_RESOLVER_ADDR")]
    domain_checker_resolver_addr: String,

    #[arg(long, required = true, env = "DOMIPLY_DOMAIN_CONFIG_STORE_DIR_PATH")]
    domain_config_store_dir_path: path::PathBuf,
}

fn main() {
    let config = Cli::parse();

    let tokio_runtime = std::sync::Arc::new(
        tokio::runtime::Builder::new_multi_thread()
            .enable_all()
            .build()
            .unwrap(),
    );

    let (stop_ch_tx, stop_ch_rx) = tokio_runtime.block_on(async { oneshot::channel() });

    // set up signal handling, stop_ch_rx will be used to signal that the stop signal has been
    // received
    tokio_runtime.spawn(async move {
        let mut signals = Signals::new(&[signal::SIGTERM, signal::SIGINT, signal::SIGQUIT])
            .expect("initialized signals");

        if let Some(_) = signals.next().await {
            println!("Gracefully shutting down...");
            let _ = stop_ch_tx.send(());
        }

        if let Some(_) = signals.next().await {
            println!("Forcefully shutting down");
            std::process::exit(1);
        };
    });

    let origin_store = domiply::origin::store::git::new(config.origin_store_git_dir_path)
        .expect("git origin store initialized");

    let domain_checker = domiply::domain::checker::new(
        tokio_runtime.clone(),
        config.domain_checker_target_cname.clone(),
        &config.domain_checker_resolver_addr,
    )
    .expect("domain checker initialized");

    let domain_config_store = domiply::domain::config::new(&config.domain_config_store_dir_path)
        .expect("domain config store initialized");

    let manager = domiply::domain::manager::new(origin_store, domain_config_store, domain_checker);
    let manager = sync::Arc::new(manager);

    let service = domiply::service::new(
        manager,
        config.domain_checker_target_cname,
        config.passphrase,
    );

    let service = sync::Arc::new(service);

    let make_service =
        hyper::service::make_service_fn(move |_conn: &hyper::server::conn::AddrStream| {
            let service = service.clone();

            // Create a `Service` for responding to the request.
            let service = hyper::service::service_fn(move |req| {
                domiply::service::handle_request(service.clone(), req)
            });

            // Return the service to hyper.
            async move { Ok::<_, Infallible>(service) }
        });

    tokio_runtime.block_on(async {
        let addr = config.http_listen_addr;

        println!("Listening on {addr}");
        let server = hyper::Server::bind(&addr).serve(make_service);

        let graceful = server.with_graceful_shutdown(async {
            stop_ch_rx.await.ok();
        });

        if let Err(e) = graceful.await {
            panic!("server error: {}", e);
        }
    });

    println!("Graceful shutdown complete");
}