use std::sync::atomic::Ordering;

use crossterm::event::{self, EventStream, KeyCode, KeyEventKind, KeyModifiers};
use futures::{FutureExt, StreamExt};
use tokio::sync::mpsc::Sender;

use crate::player::Messages;

use super::VOLUME_TIMER;

/// Starts the listener to recieve input from the terminal for various events.
pub async fn listen(sender: Sender<Messages>) -> eyre::Result<()> {
    let mut reader = EventStream::new();

    loop {
        let Some(Ok(event::Event::Key(event))) = reader.next().fuse().await else {
            continue;
        };

        if event.kind == KeyEventKind::Release {
            continue;
        }

        let messages = match event.code {
            // Arrow key volume controls.
            KeyCode::Up => Messages::ChangeVolume(0.1),
            KeyCode::Right => Messages::ChangeVolume(0.01),
            KeyCode::Down => Messages::ChangeVolume(-0.1),
            KeyCode::Left => Messages::ChangeVolume(-0.01),
            KeyCode::Char(character) => match character.to_ascii_lowercase() {
                // Ctrl+C
                'c' if event.modifiers == KeyModifiers::CONTROL => Messages::Quit,

                // Quit
                'q' => Messages::Quit,

                // Skip/Next
                's' | 'n' => Messages::Next,

                // Pause
                'p' => Messages::PlayPause,

                // Volume up & down
                '+' | '=' => Messages::ChangeVolume(0.1),
                '-' | '_' => Messages::ChangeVolume(-0.1),

                _ => continue,
            },
            // Media keys
            KeyCode::Media(media) => match media {
                event::MediaKeyCode::Play => Messages::PlayPause,
                event::MediaKeyCode::Pause => Messages::PlayPause,
                event::MediaKeyCode::PlayPause => Messages::PlayPause,
                event::MediaKeyCode::Stop => Messages::Pause,
                event::MediaKeyCode::TrackNext => Messages::Next,
                event::MediaKeyCode::LowerVolume => Messages::ChangeVolume(-0.1),
                event::MediaKeyCode::RaiseVolume => Messages::ChangeVolume(0.1),
                event::MediaKeyCode::MuteVolume => Messages::ChangeVolume(-1.0),
                _ => continue,
            },
            _ => continue,
        };

        // If it's modifying the volume, then we'll set the `VOLUME_TIMER` to 1
        // so that the UI thread will know that it should show the audio bar.
        if let Messages::ChangeVolume(_) = messages {
            VOLUME_TIMER.store(1, Ordering::Relaxed);
        }

        sender.send(messages).await?;
    }
}