use std::sync::Arc;

use clap::Parser;
use clap::Subcommand;
use tokio_listener::Listener;
use tokio_listener::SystemOptions;
use tokio_listener::UserOptions;
use tonic::{self, transport::Server};
use tracing::{info, Level};
use tracing_subscriber::prelude::*;
use tvix_build::{
    buildservice,
    proto::{build_service_server::BuildServiceServer, GRPCBuildServiceWrapper},
};
use tvix_castore::blobservice;
use tvix_castore::directoryservice;

#[cfg(feature = "tonic-reflection")]
use tvix_build::proto::FILE_DESCRIPTOR_SET;
#[cfg(feature = "tonic-reflection")]
use tvix_castore::proto::FILE_DESCRIPTOR_SET as CASTORE_FILE_DESCRIPTOR_SET;

#[derive(Parser)]
#[command(author, version, about, long_about = None)]
struct Cli {
    /// Whether to log in JSON
    #[arg(long)]
    json: bool,

    #[arg(long)]
    log_level: Option<Level>,

    #[command(subcommand)]
    command: Commands,
}
#[derive(Subcommand)]
enum Commands {
    /// Runs the tvix-build daemon.
    Daemon {
        #[arg(long, short = 'l')]
        listen_address: Option<String>,

        #[arg(long, env, default_value = "grpc+http://[::1]:8000")]
        blob_service_addr: String,

        #[arg(long, env, default_value = "grpc+http://[::1]:8000")]
        directory_service_addr: String,

        #[arg(long, env, default_value = "dummy://")]
        build_service_addr: String,
    },
}

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let cli = Cli::parse();

    // configure log settings
    let level = cli.log_level.unwrap_or(Level::INFO);

    let subscriber = tracing_subscriber::registry()
        .with(
            cli.json.then_some(
                tracing_subscriber::fmt::Layer::new()
                    .with_writer(std::io::stderr.with_max_level(level))
                    .json(),
            ),
        )
        .with(
            (!cli.json).then_some(
                tracing_subscriber::fmt::Layer::new()
                    .with_writer(std::io::stderr.with_max_level(level))
                    .pretty(),
            ),
        );

    tracing::subscriber::set_global_default(subscriber).expect("Unable to set global subscriber");

    match cli.command {
        Commands::Daemon {
            listen_address,
            blob_service_addr,
            directory_service_addr,
            build_service_addr,
        } => {
            // initialize stores
            let blob_service = blobservice::from_addr(&blob_service_addr).await?;
            let directory_service = directoryservice::from_addr(&directory_service_addr).await?;

            let build_service = buildservice::from_addr(
                &build_service_addr,
                Arc::from(blob_service),
                Arc::from(directory_service),
            )
            .await?;

            let listen_address = listen_address
                .unwrap_or_else(|| "[::]:8000".to_string())
                .parse()
                .unwrap();

            let mut server = Server::builder();

            #[allow(unused_mut)]
            let mut router = server.add_service(BuildServiceServer::new(
                GRPCBuildServiceWrapper::new(build_service),
            ));

            #[cfg(feature = "tonic-reflection")]
            {
                let reflection_svc = tonic_reflection::server::Builder::configure()
                    .register_encoded_file_descriptor_set(CASTORE_FILE_DESCRIPTOR_SET)
                    .register_encoded_file_descriptor_set(FILE_DESCRIPTOR_SET)
                    .build()?;
                router = router.add_service(reflection_svc);
            }

            info!(listen_address=%listen_address, "listening");

            let listener = Listener::bind(
                &listen_address,
                &SystemOptions::default(),
                &UserOptions::default(),
            )
            .await?;

            router.serve_with_incoming(listener).await?;
        }
    }

    Ok(())
}