use anyhow::{anyhow, bail, Result};
use clap::Parser;
use jellycommon::{ItemInfo, SourceTrack, SourceTrackKind};
use jellymatroska::{
    matroska::MatroskaTag,
    read::EbmlReader,
    unflatten::{Unflat, Unflatten},
    Master,
};
use log::{debug, error, info, trace, warn};
use std::{fs::File, io::Write, path::PathBuf};

#[derive(Parser)]
struct Args {
    #[clap(short = 'I', long)]
    item: PathBuf,
    #[clap(short = 'd', long)]
    dry: bool,
    #[clap(short = 'i', long)]
    input: PathBuf,
}

fn main() -> anyhow::Result<()> {
    env_logger::init_from_env("LOG");
    let args = Args::parse();

    let mut iteminfo: ItemInfo = serde_json::from_reader(File::open(&args.item)?)?;
    // let iteminfo_orig = iteminfo.clone();

    let input = File::open(args.input.clone()).unwrap();
    let mut input = EbmlReader::new(input);

    read(&mut input, &mut iteminfo)?;

    let k = serde_json::to_string_pretty(&iteminfo)?;
    if args.dry {
        println!("{k}")
    } else {
        let mut f = File::create(args.item)?;
        f.write_all(k.as_bytes())?;
    }

    Ok(())
}

pub fn read(input: &mut EbmlReader, iteminfo: &mut ItemInfo) -> Result<()> {
    // TODO dont traverse the entire file, if the tracks are listed at the end
    let mut sbc = 0;
    while let Some(item) = input.next() {
        let item = item?;
        match item {
            MatroskaTag::Cluster(_) => {
                info!("start of cluster found");
                let mut iter = Unflatten::new_with_end(input, item);
                while let Some(Ok(Unflat { children, item })) = iter.next() {
                    match item {
                        MatroskaTag::BlockGroup(_) => {
                            debug!("group");
                            let mut iter = children.unwrap();
                            while let Some(Ok(Unflat { children, item })) = iter.next() {
                                match item {
                                    MatroskaTag::Block(_) => (),
                                    _ => trace!("{item:?}"),
                                }
                            }
                        }
                        MatroskaTag::SimpleBlock(_) => {
                            // debug!("simple");
                        }
                        _ => debug!("(rc) tag ignored: {item:?}"),
                    }
                }
                sbc += 1;
            }
            MatroskaTag::Tags(_) => {
                Unflatten::new_with_end(input, item);
            }
            MatroskaTag::Cues(_) => {
                let mut iter = Unflatten::new_with_end(input, item);
                while let Some(Ok(Unflat { children, item })) = iter.next() {
                    match item {
                        MatroskaTag::CuePoint(_) => {
                            let mut children = children.unwrap();
                            while let Some(Ok(Unflat { children, item })) = children.next() {
                                // error!("{item:?}")
                            }
                        }
                        _ => (),
                    }
                }
            }
            MatroskaTag::Chapters(_) => {
                Unflatten::new_with_end(input, item);
            }
            MatroskaTag::Tracks(_) => {
                let mut iter = Unflatten::new_with_end(input, item);
                while let Some(Ok(Unflat { children, item })) = iter.next() {
                    match item {
                        MatroskaTag::TrackEntry(_) => {
                            let mut children = children.unwrap();
                            let (
                                mut index,
                                mut language,
                                mut codec,
                                mut kind,
                                mut sample_rate,
                                mut channels,
                                mut width,
                                mut height,
                                mut name,
                                mut fps,
                                mut bit_depth,
                            ) = (
                                None, None, None, None, None, None, None, None, None, None, None,
                            );
                            while let Some(Ok(Unflat { children, item })) = children.next() {
                                match item {
                                    MatroskaTag::CodecID(b) => codec = Some(b),
                                    MatroskaTag::Language(v) => language = Some(v),
                                    MatroskaTag::TrackNumber(v) => index = Some(v),
                                    MatroskaTag::TrackType(v) => kind = Some(v),
                                    MatroskaTag::Name(v) => name = Some(v),
                                    MatroskaTag::Audio(_) => {
                                        let mut children = children.unwrap();
                                        while let Some(Ok(Unflat { item, .. })) = children.next() {
                                            match item {
                                                MatroskaTag::Channels(v) => {
                                                    channels = Some(v as usize)
                                                }
                                                MatroskaTag::SamplingFrequency(v) => {
                                                    sample_rate = Some(v)
                                                }
                                                MatroskaTag::BitDepth(v) => bit_depth = Some(v),
                                                _ => (),
                                            }
                                        }
                                    }
                                    MatroskaTag::Video(_) => {
                                        let mut children = children.unwrap();
                                        while let Some(Ok(Unflat { item, .. })) = children.next() {
                                            match item {
                                                MatroskaTag::PixelWidth(v) => width = Some(v),
                                                MatroskaTag::PixelHeight(v) => height = Some(v),
                                                MatroskaTag::FrameRate(v) => fps = Some(v),
                                                _ => (),
                                            }
                                        }
                                    }
                                    _ => (),
                                }
                            }
                            let index = index.unwrap();
                            let kind = match kind.ok_or(anyhow!("track type required"))? {
                                1 => SourceTrackKind::Video {
                                    fps: fps.unwrap_or(f64::NAN), // TODO
                                    width: width.unwrap(),
                                    height: height.unwrap(),
                                },
                                2 => SourceTrackKind::Audio {
                                    bit_depth: bit_depth.unwrap_or(0) as usize, // TODO
                                    channels: channels.unwrap(),
                                    sample_rate: sample_rate.unwrap(),
                                },
                                17 => SourceTrackKind::Subtitles,
                                _ => bail!("invalid track type"),
                            };
                            iteminfo.tracks.insert(
                                index,
                                SourceTrack {
                                    name: name.unwrap_or_else(|| "unnamed".to_string()),
                                    codec: codec.unwrap(),
                                    language: language.unwrap_or_else(|| "none".to_string()),
                                    kind,
                                },
                            );
                        }
                        _ => debug!("(rt) tag ignored: {item:?}"),
                    }
                }
            }
            MatroskaTag::Segment(Master::End) => break,
            _ => debug!("(r) tag ignored: {item:?}"),
        }
    }
    info!("clusters {sbc}");
    Ok(())
}