require 'downloader'
require 'system'
require_relative 'data/resources/iso-images'
require 'vm/qemu'

module VirtualMachine 
    def self.distro(name, arch, type = :install)
        ISO_URLS[:debian][:arm64][:install]
    end

    def self.setup(options)
        if options[:name] == nil 
            options[:name] = options[:distro]
        end
        
        if options[:arch] == nil 
            options[:arch] = System::ARCH
        else 
            options[:arch] = System.arch_to_symbol(options[:arch])
        end

        puts options

        distro = options[:distro]
        type = :install
        arch = options[:arch]
        url = distro(name, arch, type)
        
        Downloader.get(url) do |path|
            disk_img_path = File.join(User.cache_path, "vm", distro.to_s, arch.to_s, options[:name], "root.img")
            create_disk_image(disk_img_path, 15000)
            
            puts path
            puts disk_img_path

            Qemu.launch(
                arch,
                disk_img_path,
                cpus: [1, System.cpus - 2].max,
                cdrom: path,
                detach: false
            )
        end
    end

    # size in MB
    # lsof /Users/artur/.cache/dat/vm/debian/arm64/debian/root.img
    def self.create_disk_image(path, size)
        size_in_bytes = 1024 * 1024 * size

        # Ensure the directory exists
        dir = File.dirname(path)
        FileUtils.mkdir_p(dir) unless Dir.exist?(dir)

        File.open(path, "wb") do |f|
            f.truncate(size_in_bytes)
            # f.seek(size_in_bytes - 1)
            # f.write("\0")
        end
    end
end