use git_object::borrowed;
use std::path::PathBuf;

/// A database for reading and writing objects to disk, one file per object.
pub struct Db {
    /// The directory in which objects are stored, containing 256 folders representing the hashes first byte.
    pub path: PathBuf,
}

/// Initialization
impl Db {
    /// Initialize the Db with the `objects_directory` containing the hexadecimal first byte subdirectories, which in turn
    /// contain all loose objects.
    ///
    /// In a git repository, this would be `.git/objects`.
    pub fn at(objects_directory: impl Into<PathBuf>) -> Db {
        Db {
            path: objects_directory.into(),
        }
    }
}

pub(crate) fn sha1_path(id: borrowed::Id<'_>, mut root: PathBuf) -> PathBuf {
    match id.kind() {
        git_hash::Kind::Sha1 => {
            let hex = id.to_sha1_hex();
            let buf = std::str::from_utf8(&hex).expect("ascii only in hex");
            root.push(&buf[..2]);
            root.push(&buf[2..]);
            root
        }
    }
}

///
pub mod iter;
///
pub mod locate;
///
pub mod write;