//! XRPC API server.
//!
//! Serves XRPC endpoints via axum routers built with `jacquard-axum`'s
//! `IntoRouter` helper.

mod admin;
mod get_repo_status;
mod hello;
mod list_repos;
mod list_repos_by_collection;

use admin::{admin_page, admin_status};
use get_repo_status::get_repo_status;
use list_repos::list_repos;
use list_repos_by_collection::list_repos_by_collection;

use std::net::SocketAddr;

use jacquard_common::url::Host;

use crate::com_atproto::sync::list_repos_by_collection::ListReposByCollectionRequest;
use jacquard_api::com_atproto::sync::{
    get_repo_status::GetRepoStatusRequest, list_repos::ListReposRequest,
};
use jacquard_axum::IntoRouter;

use crate::error::Result;
use crate::http::ThrottledClient;
use crate::storage::DbRef;
use crate::sync::resync::dispatcher::DispatcherState;

/// Config for the admin endpoints. Only constructed when `--admin-password` is
/// set; when absent the `/admin/*` routes are not registered at all.
#[derive(Clone)]
pub struct AdminConfig {
    /// The relay/PDS host that lightrail is subscribed to and backfilling from.
    pub subscribe_host: Host,
    /// Required Bearer token for all admin endpoints.
    pub admin_password: String,
}

/// Build and serve the axum application on `addr`.
///
/// Routes always registered:
///   GET /xrpc/com.atproto.sync.getRepoStatus
///   GET /xrpc/com.atproto.sync.listRepos
///   GET /xrpc/com.atproto.sync.listReposByCollection
///
/// Registered only when `admin_config` is `Some`:
///   GET /admin/status
pub async fn serve(
    addr: SocketAddr,
    db: DbRef,
    token: tokio_util::sync::CancellationToken,
    admin_config: Option<AdminConfig>,
    dispatcher_state: Option<DispatcherState>,
    client: Option<ThrottledClient>,
) -> Result<()> {
    let base = GetRepoStatusRequest::into_router(get_repo_status)
        .merge(ListReposRequest::into_router(list_repos))
        .merge(ListReposByCollectionRequest::into_router(
            list_repos_by_collection,
        ));

    let app = if let Some(config) = admin_config {
        let mut app = base
            .route("/admin", axum::routing::get(admin_page))
            .route("/admin/status", axum::routing::get(admin_status))
            .route("/", axum::routing::get(hello::hello))
            .with_state(db)
            .layer(axum::Extension(config));
        if let Some(ds) = dispatcher_state {
            app = app.layer(axum::Extension(ds));
        }
        if let Some(c) = client {
            app = app.layer(axum::Extension(c));
        }
        app
    } else {
        base.route("/", axum::routing::get(hello::hello))
            .with_state(db)
    };

    let listener = tokio::net::TcpListener::bind(addr).await?;
    axum::serve(listener, app)
        .with_graceful_shutdown(token.cancelled_owned())
        .await?;
    Ok(())
}