use anyhow::Result;
use clap::Parser;
use std::{borrow::Cow, net::SocketAddr, str::FromStr, sync::Arc};
use tokio::sync::mpsc;
use tracing_subscriber::{fmt, prelude::*, EnvFilter};

use cerulea_relay::{
    http::{self},
    relay::index::index_servers,
    sequencer::start_sequencer,
    AppState,
};

#[derive(Parser, Debug)]
#[command(version, about, long_about = None)]
struct Args {
    /// Bind address for the service
    #[arg(short, long, default_value = "127.0.0.1:3000")]
    bind_addr: SocketAddr,

    /// Database RAM cache capacity in megabytes
    #[arg(long, default_value_t = 1024)]
    cache_capacity: u64,

    /// did:plc directory HTTPS host. defaults to plc.directory if unset
    #[arg(long)]
    plc_resolver: Option<String>,

    #[arg(long)]
    drop_user_cache: bool,
}

#[tokio::main]
async fn main() -> Result<()> {
    let args = Args::parse();

    tracing_subscriber::registry()
        .with(fmt::layer())
        .with(EnvFilter::from_str("cerulea_relay=debug").unwrap())
        .init();

    let db = sled::Config::default()
        .path("data")
        .cache_capacity(args.cache_capacity * 1024 * 1024)
        .use_compression(true)
        .open()
        .expect("Failed to open database");

    if args.drop_user_cache {
        let _ = db.drop_tree("users");
    }

    let (event_tx, event_rx) = mpsc::channel(128);

    let mut server = AppState::new(db, event_tx);
    if let Some(plc_directory) = args.plc_resolver {
        server.plc_resolver = Cow::Owned(plc_directory);
    }

    let server = Arc::new(server);
    let initial_hosts: Vec<String> = {
        let hosts = server.known_good_hosts.lock().await;
        hosts.iter().cloned().collect()
    };
    tracing::debug!(hosts = ?initial_hosts, "got initial hosts");

    index_servers(Arc::clone(&server), &initial_hosts);
    start_sequencer(Arc::clone(&server), event_rx);

    http::listen(server, args.bind_addr).await?;
    Ok(())
}