require 'net/http'
require 'uri'
require 'open3'
require 'fileutils'
require 'open-uri'

module Archive
    MAGIC_NUMBERS = {
        "\x1F\x8B" => 'gzip',
        "\x50\x4B\x03\x04" => 'zip',
        "\x28\xB5\x2F\xFD" => 'zstd',
        "\xFD\x37\x7A\x58" => 'xz'
    }

    def self.detect_format_from_url(url)
        case File.extname(url)
        when '.gz', '.tgz' then 'gzip'
        when '.zip' then 'zip'
        when '.zst' then 'zstd'
        when '.xz' then 'xz'
        else nil
        end
    end

    def self.detect_format_from_headers(uri)
        response = Net::HTTP.get_response(uri)
        content_type = response['content-type']
        case content_type
        when /gzip/ then 'gzip'
        when /zip/ then 'zip'
        when /zstd/ then 'zstd'
        when /xz/ then 'xz'
        else nil
        end
    end

    def self.detect_format_from_magic(file_path)
        File.open(file_path, 'rb') do |f|
            bytes = f.read(4)
            MAGIC_NUMBERS.each do |magic, format|
            return format if bytes.start_with?(magic)
            end
        end
        nil
    end

    def self.download_file(uri, output_path)
        URI.open(uri) do |input|
            File.open(output_path, 'wb') do |output|
            IO.copy_stream(input, output)
            end
        end
    end

    def self.extract_archive(file_path, format)
        case format
        when 'gzip'
            system("tar -xzf #{Shellwords.escape(file_path)}")
        when 'zip'
            system("unzip #{Shellwords.escape(file_path)}")
        when 'zstd'
            system("unzstd #{Shellwords.escape(file_path)}")
        when 'xz'
            system("tar -xJf #{Shellwords.escape(file_path)}")
        else
            raise "Unsupported archive format: #{format}"
        end
    end

    def self.fetch_and_extract(url)
        uri = URI.parse(url)
        file_name = File.basename(uri.path)
        tmp_path = "/tmp/#{file_name}"

        format = detect_format_from_url(url)
        puts "format #{format}"
        download_file(uri, tmp_path)

        unless format
            format = detect_format_from_headers(uri)
        end

        unless format
            format = detect_format_from_magic(tmp_path)
        end

        raise "Could not determine archive format" unless format

        extract_archive(tmp_path, format)
    end
end
    # Example usage:
    # fetch_and_extract("https://codeberg.org/forgejo/forgejo/releases/download/v12.0.1/forgejo-12.0.1-linux-amd64.xz")