loadsmith-manifest 0.3.1

use std::{fs, future::Future, io::Cursor, path::Path};

use loadsmith_core::FileUrl;
use url::Url;

use crate::{Error, Result};

/// Download and extract a package to the given target directory.
///
/// The `file` URL determines the source:
/// - `FileUrl::Url` calls the provided `download` callback to fetch the bytes.
/// - `FileUrl::Path` pointing to a directory copies it recursively.
/// - `FileUrl::Path` pointing to a `.zip` file extracts it.
/// - `FileUrl::Path` pointing to any other file copies it as-is.
///
/// # Examples
///
/// ```rust,no_run
/// # async fn example() {
/// use loadsmith_core::FileUrl;
/// use loadsmith_manifest::download_and_extract;
///
/// let url = FileUrl::try_from_url("https://example.com/mod.zip").unwrap();
/// download_and_extract(url, "/tmp/target", |_u| async move {
///     Ok::<_, std::io::Error>(vec![])
/// }).await.unwrap();
/// # }
/// ```
pub async fn download_and_extract<F, Fut, E>(
    file: FileUrl,
    target: impl AsRef<Path>,
    download: F,
) -> Result<()>
where
    F: FnOnce(Url) -> Fut,
    Fut: Future<Output = std::result::Result<Vec<u8>, E>>,
    E: std::error::Error + Send + Sync + 'static,
{
    let target = target.as_ref();

    let zip_bytes = match file {
        FileUrl::Url(url) => download(url)
            .await
            .map_err(|err| Error::Download(Box::new(err)))?,
        FileUrl::Path(path) => {
            let metadata = path.metadata()?;

            if metadata.is_dir() {
                fs::create_dir_all(target)?;
                loadsmith_util::copy_dir(&path, target)?;
                return Ok(());
            }

            if path.extension().is_none_or(|ext| ext != "zip") {
                let canon = path.canonicalize()?;
                let file_name = canon
                    .file_name()
                    .expect("file name should exist for a file path");

                fs::create_dir_all(target)?;
                fs::copy(&canon, target.join(file_name))?;
                return Ok(());
            }

            fs::read(&path)?
        }
    };

    loadsmith_install::extract(Cursor::new(zip_bytes), target)?;

    Ok(())
}