use crate::*;
use std::fs::File;
use std::io::{BufReader, Read};
use lofty::{
    file::TaggedFileExt,
    probe::Probe,
    tag::Accessor,
};

pub struct Taggart {
    pub _root:     PathBuf,
    pub paths:     Vec<Entry>,
    pub cursor:    usize,
    pub offset:    usize,
    pub column:    usize,
    pub columns:   Columns<Entry>,
    pub size:      Measure<TuiOut>,
    pub editing:   Option<(usize, String)>,
}

#[derive(Ord, Eq, PartialEq, PartialOrd)]
pub struct Entry {
    pub path:  PathBuf,
    pub depth: usize,
    pub info:  EntryInfo,
}

#[derive(Ord, Eq, PartialEq, PartialOrd)]
pub enum EntryInfo {
    Directory {
        hash_file:    Option<()>,
        catalog_file: Option<()>,
        artist_file:  Option<()>,
        release_file: Option<()>,
    },
    Music {
        hash:      Arc<str>,
        file_type: Option<&'static FileType>,
        artist:    Option<Arc<str>>,
        album:     Option<Arc<str>>,
        track:     Option<u32>,
        title:     Option<Arc<str>>,
        date:      Option<Arc<str>>,
        year:      Option<u32>,
        people:    Option<Vec<Arc<str>>>,
        publisher: Option<Arc<str>>,
        key:       Option<Arc<str>>,
        bpm:       Option<Arc<str>>,
        invalid:   bool,
    },
    Image {
        hash:      Arc<str>,
        file_type: Option<&'static FileType>,
        title:     Option<String>,
        author:    Option<String>,
        invalid:   bool,
    },
    Unknown {
        hash:      Arc<str>,
        file_type: Option<&'static FileType>,
    }
}

impl Taggart {
    pub fn new (root: &impl AsRef<Path>, paths: Vec<Entry>) -> Usually<Self> {
        Ok(Self {
            _root:   root.as_ref().into(),
            cursor:  0,
            offset:  0,
            column:  0,
            size:    Measure::new(),
            editing: None,
            columns: Columns::default(),
            paths,
        })
    }
}

impl Entry {
    pub fn new (root: &impl AsRef<Path>, path: &impl AsRef<Path>, depth: usize) -> Perhaps<Self> {
        let path = path.as_ref();
        if path.is_dir() {
            Self::new_dir(root, &path, depth)
        } else if path.is_file() {
            Self::new_file(root, &path, depth)
        } else {
            Ok(None)
        }
    }
    fn new_dir (_: &impl AsRef<Path>, path: &Path, depth: usize) -> Perhaps<Self> {
        Ok(Some(Self {
            depth,
            path: path.into(),
            info: EntryInfo::Directory {
                hash_file:    None,
                catalog_file: None,
                artist_file:  None,
                release_file: None,
            },
        }))
    }
    fn new_file (_: &impl AsRef<Path>, path: &Path, depth: usize) -> Perhaps<Self> {
        Ok(Some(Self {
            depth,
            info: EntryInfo::new(path)?,
            path: path.into(),
        }))
    }
    pub fn is_dir (&self) -> bool {
        matches!(self.info, EntryInfo::Directory { .. })
    }
    pub fn is_mus (&self) -> bool {
        matches!(self.info, EntryInfo::Music { .. })
    }
    pub fn is_img (&self) -> bool {
        matches!(self.info, EntryInfo::Image { .. })
    }
    pub fn hash (&self) -> Option<Arc<str>> {
        match self.info {
            EntryInfo::Image { ref hash, .. } => Some(hash.clone()),
            EntryInfo::Music { ref hash, .. } => Some(hash.clone()),
            _ => None
        }
    }
    pub fn artist (&self) -> Option<Arc<str>> {
        match self.info {
            EntryInfo::Music { ref artist, .. } => artist.clone(),
            _ => None
        }
    }
    pub fn album (&self) -> Option<Arc<str>> {
        match self.info {
            EntryInfo::Music { ref album, .. } => album.clone(),
            _ => None
        }
    }
    pub fn title (&self) -> Option<Arc<str>> {
        match self.info {
            EntryInfo::Music { ref title, .. } => title.clone(),
            _ => None
        }
    }
    pub fn track (&self) -> Option<Arc<str>> {
        match self.info {
            EntryInfo::Music { ref track, .. } => track.map(|t|format!("{t}").into()).clone(),
            _ => None
        }
    }
}
impl EntryInfo {
    pub fn new (path: &Path) -> Usually<Self> {
        let reader = BufReader::new(File::open(path)?);
        let probe = Probe::new(reader)
            //.options(ParseOptions::new().parsing_mode(ParsingMode::Strict))
            .guess_file_type()?;
        if probe.file_type().is_some() {
            let file = lofty::read_from_path(path)?;
            let tag  = file.primary_tag();
            let hash = hex::encode(xxh3_64(std::fs::read(path)?.as_slice()).to_be_bytes()).into();
            Ok(Self::Music {
                hash,
                file_type: None,
                artist:    tag.map(|t|t.artist().map(|t|t.into())).flatten(),
                album:     tag.map(|t|t.album().map(|t|t.into())).flatten(),
                track:     tag.map(|t|t.track().map(|t|t.into())).flatten(),
                title:     tag.map(|t|t.title().map(|t|t.into())).flatten(),
                year:      tag.map(|t|t.year().map(|t|t.into())).flatten(),
                date:      None,
                people:    None,
                publisher: None,
                key:       None,
                bpm:       None,
                invalid:   false,
            })
        } else {
            Self::new_fallback(path)
        }
    }
    pub fn new_fallback (path: &Path) -> Usually<Self> {
        let mut reader = BufReader::new(File::open(path)?);
        let mut bytes = vec![0;16];
        reader.read(&mut bytes)?;
        // PNG
        if bytes.starts_with(&[0x89, b'P', b'N', b'G', 0x0D, 0x0A, 0x1A, 0x0A]) {
            let mut bytes = vec![];
            BufReader::new(File::open(path)?).read(&mut bytes)?;
            return Ok(Self::Image {
                file_type: None,
                hash:      hex::encode(xxh3_64(&bytes).to_be_bytes()).into(),
                title:     None,
                author:    None,
                invalid:   false,
            })
        }
        // JPG
        if bytes.starts_with(&[0xFF, 0xD8, 0xFF, 0xDB])
        || bytes.starts_with(&[0xFF, 0xD8, 0xFF, 0xE0,
                               0x00, 0x10, 0x4A, 0x46,
                               0x49, 0x46, 0x00, 0x01])
        || bytes.starts_with(&[0xFF, 0xD8, 0xFF, 0xEE])
        || (bytes.starts_with(&[0xFF, 0xD8, 0xFF, 0xE1]) &&
            bytes.get(6)  == Some(&0x45) && bytes.get(7)  == Some(&0x78) &&
            bytes.get(8)  == Some(&0x69) && bytes.get(9)  == Some(&0x66) &&
            bytes.get(10) == Some(&0x00) && bytes.get(11) == Some(&0x00))
        {
            return Ok(Self::Image {
                file_type: None,
                hash:      hex::encode(xxh3_64(&bytes).to_be_bytes()).into(),
                title:     None,
                author:    None,
                invalid:   false,
            })
        }
        Ok(Self::Unknown {
            file_type: None,
            hash:      hex::encode(xxh3_64(&bytes).to_be_bytes()).into(),
        })
    }
}