mago 1.20.1

use std::fs;
use std::io;
use std::path::Path;

use super::error::UpdateError;

pub fn extract_file(archive_path: &Path, file_to_extract: &str, into_dir: &Path) -> Result<(), UpdateError> {
    let ext = archive_path.extension().and_then(|e| e.to_str()).unwrap_or("");

    if ext == "gz" {
        // Check for .tar.gz
        let stem = archive_path.file_stem().and_then(|s| s.to_str()).unwrap_or("");
        if stem.ends_with(".tar") {
            return extract_tar_gz(archive_path, file_to_extract, into_dir);
        }
    }

    if ext == "zip" {
        return extract_zip(archive_path, file_to_extract, into_dir);
    }

    Err(UpdateError::Update(format!("unsupported archive format: {}", archive_path.display())))
}

fn extract_tar_gz(archive_path: &Path, file_to_extract: &str, into_dir: &Path) -> Result<(), UpdateError> {
    let file = fs::File::open(archive_path)?;
    let decoder = flate2::read::GzDecoder::new(file);
    let mut archive = tar::Archive::new(decoder);

    let mut entry = archive
        .entries()?
        .filter_map(|e| e.ok())
        .find(|e| e.path().ok().is_some_and(|p| p == Path::new(file_to_extract)))
        .ok_or_else(|| UpdateError::Update(format!("could not find `{file_to_extract}` in archive")))?;

    entry.unpack_in(into_dir)?;

    Ok(())
}

fn extract_zip(archive_path: &Path, file_to_extract: &str, into_dir: &Path) -> Result<(), UpdateError> {
    let file = fs::File::open(archive_path)?;
    let mut archive = zip::ZipArchive::new(file)?;
    let mut entry = archive.by_name(file_to_extract)?;

    let output_path = into_dir.join(entry.name());
    if let Some(parent) = output_path.parent() {
        fs::create_dir_all(parent)?;
    }

    let mut output = fs::File::create(output_path)?;
    io::copy(&mut entry, &mut output)?;

    Ok(())
}