/*
    This file is part of jellything (https://codeberg.org/metamuffin/jellything)
    which is licensed under the GNU Affero General Public License (version 3); see /COPYING.
    Copyright (C) 2024 metamuffin <metamuffin.org>
*/

use anyhow::{anyhow, Result};
use jellybase::CONF;
use jellycommon::{
    stream::{StreamFormat, StreamSpec},
    LocalTrack, Node, SourceTrackKind,
};
use std::{fmt::Write, ops::Range};
use tokio::{
    io::{AsyncWriteExt, DuplexStream},
    task::spawn_blocking,
};

pub async fn hls_master_stream(
    node: Node,
    _local_tracks: Vec<LocalTrack>,
    _spec: StreamSpec,
    mut b: DuplexStream,
) -> Result<()> {
    let media = node.media.as_ref().ok_or(anyhow!("no media"))?;
    let mut out = String::new();
    writeln!(out, "#EXTM3U")?;
    writeln!(out, "#EXT-X-VERSION:4")?;
    // writeln!(out, "#EXT-X-INDEPENDENT-SEGMENTS")?;
    for (i, t) in media.tracks.iter().enumerate() {
        let uri = format!(
            "stream?{}",
            StreamSpec {
                track: vec![i],
                format: StreamFormat::HlsVariant,
                ..Default::default()
            }
            .to_query()
        );
        let r#type = match t.kind {
            SourceTrackKind::Video { .. } => "VIDEO",
            SourceTrackKind::Audio { .. } => "AUDIO",
            SourceTrackKind::Subtitles => "SUBTITLES",
        };
        writeln!(out, "#EXT-X-STREAM-INF:BANDWIDTH=5000000,TYPE={type}")?;
        writeln!(out, "{uri}")?;
    }
    tokio::spawn(async move { b.write_all(out.as_bytes()).await });
    Ok(())
}

pub async fn hls_variant_stream(
    node: Node,
    local_tracks: Vec<LocalTrack>,
    mut spec: StreamSpec,
    mut b: DuplexStream,
) -> Result<()> {
    let local_track = local_tracks.first().ok_or(anyhow!("no track"))?.to_owned();
    let track_index = spec.track[0];
    let media_info = node.media.to_owned().ok_or(anyhow!("no media?"))?;
    let frags = spawn_blocking(move || {
        jellyremuxer::fragment::fragment_index(&CONF.media_path, &node, &local_track, track_index)
    })
    .await??;

    let mut out = String::new();
    writeln!(out, "#EXTM3U")?;
    writeln!(out, "#EXT-X-PLAYLIST-TYPE:VOD")?;
    writeln!(out, "#EXT-X-TARGETDURATION:{}", media_info.duration)?;
    writeln!(out, "#EXT-X-VERSION:4")?;
    writeln!(out, "#EXT-X-MEDIA-SEQUENCE:0")?;

    spec.format = StreamFormat::Fragment;
    for (i, Range { start, end }) in frags.iter().enumerate() {
        writeln!(out, "#EXTINF:{:},", end - start)?;
        spec.index = Some(i);
        writeln!(out, "stream?{}", spec.to_query())?;
    }

    writeln!(out, "#EXT-X-ENDLIST")?;

    tokio::spawn(async move { b.write_all(out.as_bytes()).await });
    Ok(())
}