use std::{fs, path::Path};

use axum::{
    response::Redirect,
    routing::{get, get_service},
    Router,
};
use minijinja::Environment;
use ost::client::OSClient;
use serde::Serialize;
use tower_http::services::ServeDir;
use tracing::info;

pub mod error;
pub mod ost;
pub mod routes;

#[derive(Debug, Clone)]
pub struct State {
    client: OSClient,
    env: Environment<'static>,
    base_path: String,
}

lazy_static::lazy_static! {
    pub static ref INDEX: String =
        std::fs::read_to_string("assets/index.html").expect("missing template");
}

lazy_static::lazy_static! {
    pub static ref FILE_CONTAINER: String =
        std::fs::read_to_string("assets/filecontainer.html").expect("missing template");
}

#[tokio::main]
async fn main() {
    dotenv::dotenv().expect("could not load env");

    tracing_subscriber::fmt().init();

    let client = OSClient::init().await;

    info!("Successfully loaded client");

    let base_path = std::env::var("BASE_PATH").expect("base path not configured");

    let mut env = Environment::new();

    env.add_template("file_container", &FILE_CONTAINER)
        .expect("unable to add template");

    env.add_template("index", &INDEX)
        .expect("unable to add template");

    let state = State {
        client,
        env,
        base_path,
    };

    let router = axum::Router::new()
        .route("/", get(|| async { Redirect::permanent("/dir/root") }))
        .route("/dir/*key", get(routes::get_directory))
        .route("/subtitles", get(routes::search_subtitles))
        .route("/guess", get(routes::guess_it))
        .route("/download", get(routes::download_subtitles))
        .with_state(state);

    let router_static = Router::new().fallback(get_service(ServeDir::new("assets")));

    let listener = tokio::net::TcpListener::bind("0.0.0.0:3001").await.unwrap();

    axum::serve(listener, router.merge(router_static))
        .await
        .unwrap();
}

pub fn scan_dir_contents(path: impl AsRef<Path>) -> std::io::Result<Vec<FileType>> {
    let entries = fs::read_dir(path)?
        .filter_map(Result::ok)
        .collect::<Vec<_>>();

    let subs = entries
        .iter()
        .filter_map(|entry| {
            let path = entry.path();
            let ext = path.extension()?.to_str()?;
            let (name, _) = path.file_name()?.to_str()?.split_once(ext)?;
            (ext == "srt").then_some(name.to_owned())
        })
        .collect::<Vec<_>>();

    let mut files: Vec<_> = entries
        .iter()
        .filter_map(|entry| {
            if entry.path().is_dir() {
                Some(FileType::Directory(Directory {
                    name: entry.file_name().to_str().unwrap_or_default().to_string(),
                    path: entry.path().to_str().unwrap_or_default().to_string(),
                }))
                // Skip existing subtitles
            } else if entry.path().extension().is_some_and(|ext| {
                ext.to_str().is_some_and(|ext| ext == "srt")
                    || ext.to_str().is_some_and(|ext| ext == "smi")
            }) {
                None
            } else {
                let path = entry.path();
                let ext = path.extension()?.to_str()?;
                let (name, _) = path.file_name()?.to_str()?.split_once(ext)?;
                Some(FileType::File(File {
                    name: entry.file_name().to_str().unwrap_or_default().to_string(),
                    path: entry.path().to_str().unwrap_or_default().to_string(),
                    has_subs: subs.contains(&name.to_string()),
                }))
            }
        })
        .collect();

    files.sort();

    Ok(files)
}

#[derive(Debug, Serialize, PartialEq, Eq, PartialOrd, Ord)]
pub enum FileType {
    Directory(Directory),
    File(File),
}

#[derive(Debug, Serialize, PartialEq, Eq, PartialOrd, Ord)]
pub struct File {
    name: String,
    path: String,

    /// `true` if a same file exists with a `.srt` extension found
    /// in the same directory
    has_subs: bool,
}

#[derive(Debug, Serialize, PartialEq, Eq, PartialOrd, Ord)]
pub struct Directory {
    name: String,

    path: String,
}