use std::net::SocketAddr;

use bus::Bus;

mod config;
mod util;
mod app;
mod system;
mod protocol;
mod manager;

use app::App;
use hyper::body::Bytes;
use hyper_util::rt::TokioIo;
use system::{
    cache::WebCache,
    net::{
        Server, Stream,
        tcp::*,
        tls::*,
    },
};

#[derive(Clone)]
struct HttpServiceArgs {
    bus:Bus<protocol::QRPacket>,
    cache:WebCache,
}

async fn service_http(mut request:hyper::Request<hyper::body::Incoming>, args:HttpServiceArgs) -> Result<hyper::Response<http_body_util::Full<Bytes>>, std::convert::Infallible>
// Serve cached files and upgrade websocket connections.
//
{
    use hyper::{Response, body::Bytes, header::{CONTENT_TYPE, CACHE_CONTROL, ACCEPT_LANGUAGE}};
    use http_body_util::Full;

    println!("Serving: {}", request.uri().path());

    let mut language_code = 0;
    if let Some(languages) = request.headers().get(ACCEPT_LANGUAGE) {
        if let Ok(languages) = languages.to_str() {
            for decl in languages.split(",") {
                let decl = decl.trim().to_lowercase();
                if decl.len() >= 2 {
                    let code = &decl[..2];

                    language_code = match code {
                        "en" => 0,
                        "ja" => 1,
                        _ => { continue; }
                    }; break;
                }
            }
        }
    }

    if hyper_tungstenite::is_upgrade_request(&request) {
        if let Ok((response, websocket)) = hyper_tungstenite::upgrade(&mut request, None) {
            tokio::task::spawn(async move {
                match websocket.await {
                    Ok(websocket) => manager::handle_ws(websocket, args).await,
                    Err(_) => Err(()),
                }.ok()
            });

            Ok(response)
        } else {
            Ok(Response::builder()
                .status(401)
                .body(Full::new(Bytes::new()))
                    .unwrap())
        }
    } else {
        match args.cache.fetch(request.uri().path()) {
            Some(data) => {
                let mut output = data.data;
                match request.uri().path() {
                    "/.js" => {
                        output = [
                            format!("let CONFIG_VERSION = \"{}\";", config::VERSION).as_bytes().to_vec(),
                            format!("let CONFIG_LANGUAGE = {};", language_code).as_bytes().to_vec(),
                            output,
                        ].concat();
                    }
                    _ => { }
                }
                
                Ok(Response::builder()
                    .header(CONTENT_TYPE, &data.mime)
                    .header(CACHE_CONTROL, "no-cache")
                    .body(Full::new(Bytes::from(output))).unwrap())
            }
            None => Ok(Response::builder()
                .header(CONTENT_TYPE, "text/html")
                .header(CACHE_CONTROL, "no-cache")
                .body(Full::new(Bytes::from(args.cache.fetch("/.html").unwrap().data))).unwrap()),
        }
    }
}

async fn handle_http<S>(stream:S, addr:SocketAddr, args:HttpServiceArgs) -> Result<(),()>
where S: tokio::io::AsyncRead + tokio::io::AsyncWrite + Unpin + Send + 'static
// Hand off socket connection to Hyper server.
//
{
    use hyper::server::conn::http1;
    use hyper::service::service_fn;

    println!("Connection from {}", addr.to_string());

    let io = TokioIo::new(stream);

    let conn = http1::Builder::new()
        .serve_connection(io, service_fn(move |req| {
            service_http(req, args.clone())
        }));
    
    conn.with_upgrades().await.ok();
    Ok(())
}

async fn handle_tcp(stream:TcpStream, addr:SocketAddr, args:HttpServiceArgs) -> Result<(),()>
{
    handle_http(stream.to_stream(), addr, args).await
}

async fn handle_tls(stream:TlsStream, addr:SocketAddr, args:HttpServiceArgs) -> Result<(),()>
{
    handle_http(stream.to_stream(), addr, args).await
}



#[tokio::main(flavor = "multi_thread", worker_threads = 12)]
async fn main()
{
    println!("Server Version: {}", config::VERSION);

    // Initialize application data.
    let app;
    if let Ok(result) = App::init() {
        app = result;
    } else {
        println!("fatal: failed to initialize server.");
        return;
    }

    // Initialize central bus and data serivce.
    let b_main :Bus<protocol::QRPacket> = Bus::new_as(bus::Mode::Transmitter);
    match b_main.connect() {
        Ok(bus) => {
            tokio::spawn(async move {
                manager::thread_system(app, bus).await;
            });
        }
        Err(_) => {
            println!("fatal: failed to initialize bus.");
            return;
        }
    }


    // Initialize HTTPS service.
    match b_main.connect() {
        Ok(bus) => {
            let cache = WebCache::new();
            cache.cache_file("text/html", "/.html", "www/.html").ok();
            cache.cache_whitespace_minimize("/.html").ok();
            cache.cache_file_group("text/css", "/.css", &[
                "www/css/main.css",
                "www/css/ui.css",
                "www/css/form.css",
                "www/css/game.css",
                "www/css/util.css",
            ]).ok();
            cache.cache_file_group("text/javascript", "/.js", &[
                "www/js/const.js",
                "www/js/language.js",
                "www/js/util.js",
                "www/js/badge.js",
                "www/js/game_asset.js",
                "www/js/game.js",
                "www/js/interface.js",
                "www/js/ui.js",
                "www/js/scene.js",
                "www/js/system.js",
                "www/js/main.js",
            ]).ok();
            cache.cache_file("image/png", "/favicon.png", "www/asset/favicon.png").ok();
            cache.cache_file("image/png", "/favicon_notify.png", "www/asset/favicon_notify.png").ok();

            let asset_path = std::path::Path::new("www/asset");
            for asset in [
                "promote.svg",

                "heart_dawn.svg",
                "behemoth_dawn.svg",
                "dragon_dawn.svg",
                "castle_dawn.svg",
                "tower_dawn.svg",
                "lance_dawn.svg",
                "knight_dawn.svg",
                "militia_dawn.svg",

                "heart_dusk.svg",
                "behemoth_dusk.svg",
                "dragon_dusk.svg",
                "castle_dusk.svg",
                "tower_dusk.svg",
                "lance_dusk.svg",
                "knight_dusk.svg",
                "militia_dusk.svg",
            ] {
                if cache.cache_file("image/svg+xml", &format!("/asset/{}", asset), asset_path.join(asset)).is_err() {
                    println!("error: failed to load: {}", asset);
                }
            }

            let about_path = std::path::Path::new("www/pages/about");
            for doc in [
                "main",
            ] {
                if cache.cache_md(&format!("/about/{}.html", doc), about_path.join(format!("{}.md", doc))).is_err() {
                    println!("error: failed to load: {}", doc);
                }
            }

            let guide_path = std::path::Path::new("www/pages/guide");
            for doc in [
                "game",
                "pieces",
                "interface",
            ] {
                if cache.cache_md(&format!("/guide/{}.html", doc), guide_path.join(format!("{}.md", doc))).is_err() {
                    println!("error: failed to load: {}", doc);
                }
            }
            
            let mut tcp_server = TcpServer::new();
            match tcp_server.bind("127.0.0.1:38611").await {
                Ok(_) => {
                    let b = bus.connect().unwrap();
                    let c = cache.clone();
                    tokio::spawn(async move {
                        while tcp_server.accept(handle_tcp, HttpServiceArgs {
                            bus:b.connect().unwrap(),
                            cache:c.clone(),
                        }).await.is_ok() { }
                    });
                }
                Err(_) => {
                    println!("error: failed to bind TCP port 38611.");
                }
            }

            let mut tls_server = TlsServer::new();
            for domain in [
                "omen.kirisame.com",
                "dzura.com",
            ] {
                if tls_server.add_cert(domain, &format!("cert/{}/fullchain.pem", domain), &format!("cert/{}/privkey.pem", domain)).await.is_err() {
                    println!("error: failed to load TLS certificates for {}.", domain);
                }
            }
            match tls_server.bind("0.0.0.0:38612").await {
                Ok(_) => {
                    let b = bus.connect().unwrap();
                    let c = cache.clone();
                    tokio::spawn(async move {
                        while tls_server.accept(handle_tls, HttpServiceArgs {
                            bus:b.connect().unwrap(),
                            cache:c.clone(),
                        }).await.is_ok() { }
                    });
                }
                Err(_) => {
                    println!("error: failed to bind TLS port 38612.");
                }
            }
        }
        Err(_) => {
            println!("error: failed to initialize HTTPS service.");
        }
    }

    loop { tokio::time::sleep(tokio::time::Duration::from_secs(10)).await; }
}