mod file_sink;

extern crate rpassword;

use std::{path::PathBuf};
use std::path::Path;

use librespot::{core::authentication::Credentials, metadata::Playlist};
use librespot::core::config::SessionConfig;
use librespot::core::session::Session;
use librespot::core::spotify_id::SpotifyId;
use librespot::playback::config::PlayerConfig;

use librespot::playback::player::Player;
use librespot::playback::audio_backend::{Open};

use librespot::metadata::{Track, Artist, Metadata, Album};

use structopt::StructOpt;

use indicatif::{ProgressBar, ProgressStyle};

#[derive(Debug, StructOpt)]
#[structopt(name = "spotify-dl", about = "A commandline utility to download music directly from Spotify")]
struct Opt {
    #[structopt(help = "A list of Spotify URIs (songs, podcasts or playlists)")]
    tracks: Vec<String>,
    #[structopt(short = "u", long = "username", help = "Your Spotify username")]
    username: String,
    #[structopt(short = "p", long = "password", help = "Your Spotify password")]
    password: Option<String>,
    #[structopt(short = "d", long = "destination", default_value = ".", help = "The directory where the songs will be downloaded")]
    destination: String
}

#[derive(Clone)]
pub struct TrackMetadata {
    artists: Vec<String>,
    track_name: String,
    album: String,
}

async fn create_session(credentials: Credentials) -> Session {
    let session_config = SessionConfig::default();
    let session = Session::connect(session_config, credentials, None).await.unwrap();
    session
}

fn make_filename_compatible(filename: &str) -> String {
    let invalid_chars = ['<', '>', ':', '\'', '"', '/', '\\', '|', '?', '*'];
    let mut clean = String::new();
    for c in filename.chars() {
        if !invalid_chars.contains(&c) && c.is_ascii() && !c.is_control() && c.len_utf8() == 1  {
            clean.push(c);
        }
    }
    clean
}

async fn download_tracks(session: &Session, destination: PathBuf, tracks: Vec<SpotifyId>) {
    let player_config = PlayerConfig::default();
    let bar_style = ProgressStyle::default_bar()
        .template("[{elapsed_precise}] {bar:40.cyan/blue} {pos:>7}/{len:7} (ETA: {eta}) {msg}")
        .progress_chars("##-");
    let bar = ProgressBar::new(tracks.len() as u64);
    bar.set_style(bar_style);
    bar.enable_steady_tick(500);

    for track in tracks {
        let track_item = Track::get(&session, track).await.unwrap();
        let artist_name: String;

        let mut metadata = TrackMetadata {
            artists: Vec::new(),
            track_name: track_item.name,
            album: Album::get(session, track_item.album).await.unwrap().name
        };
        if track_item.artists.len() > 1 {
            let mut tmp: String = String::new();
            for artist in track_item.artists {
                let artist_item = Artist::get(&session, artist).await.unwrap();
                metadata.artists.push(artist_item.name.clone());
                tmp.push_str(artist_item.name.as_str());
                tmp.push_str(", ");
            }
            artist_name = String::from(tmp.trim_end_matches(", "));
        }
        else {
            artist_name = Artist::get(&session, track_item.artists[0]).await.unwrap().name;
            metadata.artists.push(artist_name.clone());
        }
        let full_track_name = format!("{} - {}", artist_name, metadata.track_name);
        let full_track_name_clean = make_filename_compatible(full_track_name.as_str());
        let filename = format!("{}.flac", full_track_name_clean);
        let joined_path = destination.join(&filename);
        let path = joined_path.to_str().unwrap();
        bar.set_message(full_track_name_clean.as_str());
        
        let path_with_no_extension = Path::new(path).with_extension("");
        if !path_with_no_extension.exists() {
			let mut file_sink = file_sink::FileSink::open(Some(path.to_owned()), librespot::playback::config::AudioFormat::S16);
			file_sink.add_metadata(metadata);
			let (mut player, _) = Player::new(player_config.clone(), session.clone(), None, move || {
				Box::new(file_sink)
			});
			player.load(track, true, 0);
			player.await_end_of_track().await;
			player.stop();
			bar.inc(1);
        } else {
            println!("File already exists: {}", path);
			bar.inc(1);
        }
    }
    bar.finish();
}

#[tokio::main]
async fn main() {

    let opt = Opt::from_args();

    let username = opt.username;
    let password = opt.password.unwrap_or_else(|| rpassword::read_password_from_tty(Some("Password: ")).unwrap());
    let credentials = Credentials::with_password(username, password);

    let session = create_session(credentials.clone()).await;

    let mut tracks: Vec<SpotifyId> = Vec::new();

    for track_url in opt.tracks {
        let track = SpotifyId::from_uri(track_url.as_str()).unwrap();
        match &track.audio_type {
            librespot::core::spotify_id::SpotifyAudioType::Track => {
                tracks.push(track);
            }
            librespot::core::spotify_id::SpotifyAudioType::Podcast => {
                tracks.push(track);
            }
            librespot::core::spotify_id::SpotifyAudioType::NonPlayable => {
                match Playlist::get(&session, track).await {
                    Ok(mut playlist) => {
                        println!("Adding all songs from playlist {} (by {}) to the queue", &playlist.name, &playlist.user);
                        tracks.append(&mut playlist.tracks);
                    }
                    Err(_) => {
                        println!("Unsupported track {}", &track_url);
                    }
                }
            }
        }
    }

    download_tracks(&session, PathBuf::from(opt.destination), tracks).await;

}