class Chef::Knife::YamlConvert

def resource_hash_to_string(resource_hash, filename)
  ruby_contents = []
  ruby_contents << "# Autoconverted recipe from #{filename}\n"
  resource_hash.each do |r|
    type = r.delete("type")
    name = r.delete("name")
    ruby_contents << "#{type} \"#{name}\" do"
    r.each do |k, v|
      ruby_contents << "  #{k} #{v.inspect}"
    end
    ruby_contents << "end\n"
  end
  ruby_contents.join("\n")
end

def run
  if name_args.empty?
    ui.fatal!("Please specify the file name of a YAML recipe to convert to Ruby")
  elsif name_args.size >= 3
    ui.fatal!("knife yaml convert YAML_FILENAME [RUBY_FILENAME]")
  end
  yaml_file = @name_args[0]
  unless ::File.exist?(yaml_file) && ::File.readable?(yaml_file)
    ui.fatal("Input YAML file '#{yaml_file}' does not exist or is unreadable")
  end
  ruby_file = if @name_args[1]
                @name_args[1] # use the specified output filename if provided

              else
                if ::File.extname(yaml_file) == ".yml" || ::File.extname(yaml_file) == ".yaml"
                  yaml_file.gsub(/\.(yml|yaml)$/, ".rb")
                else
                  yaml_file + ".rb" # fall back to putting .rb on the end of whatever the yaml file was named

                end
              end
  if ::File.exist?(ruby_file)
    ui.fatal!("Output Ruby file '#{ruby_file}' already exists")
  end
  yaml_contents = IO.read(yaml_file)
  # YAML can contain multiple documents (--- is the separator), let's not support that.

  if ::YAML.load_stream(yaml_contents).length > 1
    ui.fatal!("YAML recipe '#{yaml_file}' contains multiple documents, only one is supported")
  end
  # Unfortunately, per the YAML spec, comments are stripped when we load, so we lose them on conversion

  yaml_hash = ::YAML.safe_load(yaml_contents, permitted_classes: [Symbol])
  unless yaml_hash.is_a?(Hash) && yaml_hash.key?("resources")
    ui.fatal!("YAML recipe '#{source_file}' must contain a top-level 'resources' hash (YAML sequence), i.e. 'resources:'")
  end
  ui.warn("No resources found in '#{yaml_file}'") if yaml_hash["resources"].size == 0
  ::File.open(ruby_file, "w") do |file|
    file.write(resource_hash_to_string(yaml_hash["resources"], yaml_file))
  end
  ui.info("Converted '#{yaml_file}' to '#{ruby_file}'")
end