use anyhow::Context;
use axum::routing::get;
use axum::routing::Router;
use clap::Parser;
use neptune_core::models::blockchain::block::block_selector::BlockSelector;
use neptune_core::rpc_server::RPCClient;
use neptune_explorer::html::page::block::block_page;
use neptune_explorer::html::page::not_found::not_found_html_fallback;
use neptune_explorer::html::page::redirect_qs_to_path::redirect_query_string_to_path;
use neptune_explorer::html::page::root::root;
use neptune_explorer::html::page::utxo::utxo_page;
use neptune_explorer::model::app_state::AppState;
use neptune_explorer::model::config::Config;
use neptune_explorer::rpc::block_digest::block_digest;
use neptune_explorer::rpc::block_info::block_info;
use neptune_explorer::rpc::utxo_digest::utxo_digest;
use std::net::Ipv4Addr;
use std::net::SocketAddr;
use std::sync::Arc;
use tarpc::client;
use tarpc::context;
use tarpc::tokio_serde::formats::Json as RpcJson;
use tower_http::services::ServeDir;

#[tokio::main]
async fn main() -> Result<(), anyhow::Error> {
    let rpc_client = rpc_client()
        .await
        .with_context(|| "Failed to create RPC client")?;
    let network = rpc_client
        .network(context::current())
        .await
        .with_context(|| "Failed calling neptune-core api: network")?;
    let genesis_digest = rpc_client
        .block_digest(context::current(), BlockSelector::Genesis)
        .await
        .with_context(|| "Failed calling neptune-core api: block_digest")?
        .with_context(|| "neptune-core failed to provide a genesis block")?;

    let shared_state = Arc::new(AppState::from((
        network,
        Config::parse(),
        rpc_client,
        genesis_digest,
    )));

    let app = Router::new()
        // -- RPC calls --
        .route("/rpc/block_info/*selector", get(block_info))
        .route("/rpc/block_digest/*selector", get(block_digest))
        .route("/rpc/utxo_digest/:index", get(utxo_digest))
        // -- Dynamic HTML pages --
        .route("/", get(root))
        .route("/block/*selector", get(block_page))
        .route("/utxo/:value", get(utxo_page))
        // -- Rewrite query-strings to path --
        .route("/rqs", get(redirect_query_string_to_path))
        // -- Static files --
        .nest_service(
            "/css",
            ServeDir::new(concat!(env!("CARGO_MANIFEST_DIR"), "/templates/web/css")),
        )
        .nest_service(
            "/image",
            ServeDir::new(concat!(env!("CARGO_MANIFEST_DIR"), "/templates/web/image")),
        )
        // handle route not-found
        .fallback(not_found_html_fallback(shared_state.clone()))
        // add state
        .with_state(shared_state);

    let port = Config::parse().listen_port;
    let listener = tokio::net::TcpListener::bind(format!("0.0.0.0:{port}"))
        .await
        .with_context(|| format!("Failed to bind to port {port}"))?;

    println!("Running on http://localhost:{port}");

    axum::serve(listener, app)
        .await
        .with_context(|| "Axum server encountered an error")?;
    Ok(())
}

async fn rpc_client() -> Result<RPCClient, anyhow::Error> {
    // Create connection to neptune-core RPC server
    let args: Config = Config::parse();
    let server_socket = SocketAddr::new(
        std::net::IpAddr::V4(Ipv4Addr::LOCALHOST),
        args.neptune_rpc_port,
    );
    let transport = tarpc::serde_transport::tcp::connect(server_socket, RpcJson::default)
        .await
        .with_context(|| {
            format!("Failed to connect to neptune-core rpc service at {server_socket}")
        })?;
    Ok(RPCClient::new(client::Config::default(), transport).spawn())
}