use anyhow::{anyhow, bail, Context, Ok};
use jellycommon::{DirectoryInfo, ItemInfo};
use log::info;
use std::{ffi::OsStr, fs::File, path::PathBuf, sync::Arc};

pub struct Library {
    pub root: Arc<Node>,
}

#[derive(Debug, Clone)]
pub enum Node {
    Directory(Arc<Directory>),
    Item(Arc<Item>),
}

#[derive(Debug, Clone)]
pub struct Directory {
    pub lib_path: PathBuf,
    pub identifier: String,
    pub data: DirectoryInfo,
    pub children: Vec<Arc<Node>>,
}

#[derive(Debug, Clone)]
pub struct Item {
    pub fs_path: PathBuf,
    pub lib_path: PathBuf,
    pub identifier: String,
    pub data: ItemInfo,
}

impl Library {
    pub fn open(path: &str) -> anyhow::Result<Self> {
        Ok(Self {
            root: Node::from_path(path.into(), PathBuf::new(), true).context("indexing root")?,
        })
    }
    pub fn nested(&self, path: &str) -> anyhow::Result<Arc<Node>> {
        let mut n = self.root.clone();
        if path == "" {
            return Ok(n);
        }
        for seg in path.split("/") {
            n = n
                .get_directory()?
                .child_by_ident(seg)
                .ok_or(anyhow!("does not exist"))?;
        }
        Ok(n)
    }
}

impl Node {
    pub fn get_directory(&self) -> anyhow::Result<Arc<Directory>> {
        match self {
            Node::Directory(d) => Ok(d.clone()),
            Node::Item(_) => bail!("not a directory"),
        }
    }
    pub fn get_item(&self) -> anyhow::Result<Arc<Item>> {
        match self {
            Node::Item(i) => Ok(i.clone()),
            Node::Directory(_) => bail!("not an item"),
        }
    }
    pub fn title(&self) -> &str {
        match self {
            Node::Directory(d) => &d.data.name,
            Node::Item(i) => &i.data.title,
        }
    }
    pub fn identifier(&self) -> &str {
        match self {
            Node::Directory(d) => &d.identifier,
            Node::Item(i) => &i.identifier,
        }
    }
    pub fn from_path(
        path: PathBuf,
        mut lib_path: PathBuf,
        root: bool,
    ) -> anyhow::Result<Arc<Node>> {
        if path.is_dir() {
            let mpath = path.join("directory.json");
            let data: DirectoryInfo =
                serde_json::from_reader(File::open(mpath).context("metadata missing")?)?;

            let identifier = path.file_name().unwrap().to_str().unwrap().to_string();
            if !root {
                lib_path = lib_path.join(identifier.clone());
            }

            let children = path
                .read_dir()?
                .filter_map(|e| {
                    let e = e.unwrap();
                    // TODO
                    if ((e.path().extension() != Some(OsStr::new("mkv"))
                        && e.path().extension() != Some(OsStr::new("webm")))
                        || e.metadata().unwrap().is_dir())
                        && !e.path().ends_with("directory.json")
                    {
                        Some(e.path())
                    } else {
                        None
                    }
                })
                .map(|e| {
                    Node::from_path(e.clone(), lib_path.clone(), false)
                        .context(format!("loading {e:?}"))
                })
                .into_iter()
                .collect::<anyhow::Result<Vec<_>>>()?;

            Ok(Node::Directory(Arc::new(Directory {
                lib_path,
                children,
                data,
                identifier,
            }))
            .into())
        } else if path.is_file() {
            info!("loading {path:?}");
            let datafile = File::open(path.clone()).context("cant load metadata")?;
            let data: ItemInfo = serde_json::from_reader(datafile).context("invalid metadata")?;
            let identifier = path
                .with_extension("")
                .file_name()
                .unwrap()
                .to_str()
                .unwrap()
                .to_string();
            Ok(Node::Item(Arc::new(Item {
                fs_path: path.clone(),
                lib_path: lib_path.join(identifier.clone()),
                data,
                identifier,
            }))
            .into())
        } else {
            bail!("did somebody really put a fifo or socket in the library?!")
        }
    }
}
impl Item {
    pub fn path(&self) -> String {
        self.lib_path.to_str().unwrap().to_string()
    }
}
impl Directory {
    pub fn path(&self) -> String {
        self.lib_path.to_str().unwrap().to_string()
    }
    pub fn child_by_ident(&self, i: &str) -> Option<Arc<Node>> {
        self.children
            .iter()
            .find(|e| e.identifier() == i)
            .map(|e| e.to_owned())
    }
}