use std::{ops::Deref, path::Path, sync::Arc, time::Duration};

use crate::{
    assets,
    config::Config,
    db::Db,
    icons::{icon, Icons},
    model::{Info, VersionInfo},
    page::page,
    storage::Storage,
    util,
};
use clokwerk::{Interval, Scheduler};
use path_macro::path;
use poem::{
    http::header, listener::TcpListener, middleware, Endpoint, EndpointExt, Route, RouteDomain,
    Server,
};
use time::OffsetDateTime;
use tokio::signal;

#[derive(Clone)]
pub struct Talon {
    i: Arc<TalonInner>,
}

pub struct TalonInner {
    pub cfg: Config,
    pub db: Db,
    pub storage: Storage,
    pub icons: Icons,
    pub start_time: OffsetDateTime,
}

impl Deref for Talon {
    type Target = TalonInner;

    fn deref(&self) -> &Self::Target {
        &self.i
    }
}

#[derive(thiserror::Error, Debug)]
pub enum TalonError {
    #[error("db error: {0}")]
    Db(#[from] crate::db::DbError),
    #[error("db error: {0}")]
    Storage(#[from] crate::storage::StorageError),
    #[error("db error: {0}")]
    Config(#[from] crate::config::ConfigError),
    #[error("io error: {0}")]
    Io(#[from] std::io::Error),
}

pub type Result<T> = std::result::Result<T, TalonError>;

impl Talon {
    pub fn new<P: AsRef<Path>>(workdir: P) -> Result<Self> {
        let db_dir = path!(workdir / "db");
        let storage_dir = path!(workdir / "storage");
        let icons_dir = path!(workdir / "icons");
        util::create_dir_ne(&workdir)?;
        util::create_dir_ne(&db_dir)?;
        util::create_dir_ne(&storage_dir)?;
        util::create_dir_ne(&icons_dir)?;

        let cfg = Config::from_file(path!(workdir / "config.toml"))?;
        let db = Db::new(db_dir)?;
        let storage = Storage::new(storage_dir, db.clone(), cfg.clone());
        let icons = Icons::new(icons_dir);

        let talon = Self {
            i: TalonInner {
                cfg,
                db,
                storage,
                icons,
                start_time: OffsetDateTime::now_utc(),
            }
            .into(),
        };

        Ok(talon)
    }

    fn scheduler(&self) -> Scheduler {
        let mut scheduler = Scheduler::new();
        let talon = self.clone();
        scheduler
            .every(Interval::Minutes(self.cfg.server.purge_interval))
            .run(move || {
                log::info!("Starting purge");
                match talon.storage.purge() {
                    Ok((files, freed)) => log::info!("{files} files purged, {freed} bytes freed"),
                    Err(e) => log::error!("purge error: {e}"),
                }
            });
        scheduler
    }

    pub fn endpoint(&self) -> impl Endpoint {
        let api_service =
            crate::api::api_service().server(format!("{}/api", self.i.cfg.server.internal_url));
        let swagger_ui = api_service.swagger_ui();
        let spec = api_service.spec();

        let route_internal = Route::new()
            .at(
                "/",
                poem::endpoint::make_sync(|_| "Hello World, I am Talon"),
            )
            .nest(
                "/api",
                api_service
                    .with(middleware::Cors::new())
                    .with(crate::middleware::LastModified),
            )
            .nest("/api/swagger", swagger_ui)
            .at(
                "/api/spec",
                poem::endpoint::make_sync(move |_| spec.clone()),
            )
            .at("/assets/menu/*path", assets::menu_assets)
            .at("/icons/:subdomain", icon);

        let internal_domain = format!(
            "{}.{}",
            self.i.cfg.server.internal_subdomain, self.i.cfg.server.root_domain
        );
        let site_domains = format!("+.{}", self.i.cfg.server.root_domain);

        RouteDomain::new()
            .at(internal_domain, route_internal)
            .at(site_domains, page)
            .at(&self.i.cfg.server.root_domain, page)
            .with(middleware::Tracing)
            .with(
                middleware::SetHeader::new().overriding(header::X_CONTENT_TYPE_OPTIONS, "nosniff"),
            )
            .data(self.clone())
    }

    async fn shutdown_signal() {
        if let Err(e) = signal::ctrl_c().await {
            log::error!("failed to listen to shutdown signal: {e}");
        }
    }

    pub async fn launch(&self) -> Result<()> {
        let scheduler = self.scheduler();
        let _scheduler_handle = scheduler.watch_thread(Duration::from_secs(1));

        Server::new(TcpListener::bind(&self.i.cfg.server.address))
            .run_with_graceful_shutdown(self.endpoint(), Self::shutdown_signal(), None)
            .await?;
        Ok(())
    }

    pub fn info(&self) -> std::result::Result<Info, crate::storage::StorageError> {
        Ok(Info {
            stats: self.storage.stats()?,
            version: VersionInfo::get(),
            start_time: self.start_time,
        })
    }
}