class Kamal::Configuration::Accessory
  delegate :argumentize, :optionize, to: Kamal::Utils

  attr_accessor :name, :specifics

  def initialize(name, config:)
    @name, @config, @specifics = name.inquiry, config, config.raw_config["accessories"][name]
  end

  def service_name
    specifics["service"] || "#{config.service}-#{name}"
  end

  def image
    specifics["image"]
  end

  def hosts
    if (specifics.keys & ["host", "hosts", "roles"]).size != 1
      raise ArgumentError, "Specify one of `host`, `hosts` or `roles` for accessory `#{name}`"
    end

    hosts_from_host || hosts_from_hosts || hosts_from_roles
  end

  def port
    if port = specifics["port"]&.to_s
      port.include?(":") ? port : "#{port}:#{port}"
    end
  end

  def publish_args
    argumentize "--publish", port if port
  end

  def labels
    default_labels.merge(specifics["labels"] || {})
  end

  def label_args
    argumentize "--label", labels
  end

  def env
    specifics["env"] || {}
  end

  def env_file
    Kamal::EnvFile.new(env)
  end

  def host_env_directory
    File.join config.host_env_directory, "accessories"
  end

  def host_env_file_path
    File.join host_env_directory, "#{service_name}.env"
  end

  def env_args
    argumentize "--env-file", host_env_file_path
  end

  def files
    specifics["files"]&.to_h do |local_to_remote_mapping|
      local_file, remote_file = local_to_remote_mapping.split(":")
      [ expand_local_file(local_file), expand_remote_file(remote_file) ]
    end || {}
  end

  def directories
    specifics["directories"]&.to_h do |host_to_container_mapping|
      host_path, container_path = host_to_container_mapping.split(":")
      [ expand_host_path(host_path), container_path ]
    end || {}
  end

  def volumes
    specific_volumes + remote_files_as_volumes + remote_directories_as_volumes
  end

  def volume_args
    argumentize "--volume", volumes
  end

  def option_args
    if args = specifics["options"]
      optionize args
    else
      []
    end
  end

  def cmd
    specifics["cmd"]
  end

  private
    attr_accessor :config

    def default_labels
      { "service" => service_name }
    end

    def expand_local_file(local_file)
      if local_file.end_with?("erb")
        with_clear_env_loaded { read_dynamic_file(local_file) }
      else
        Pathname.new(File.expand_path(local_file)).to_s
      end
    end

    def with_clear_env_loaded
      (env["clear"] || env).each { |k, v| ENV[k] = v }
      yield
    ensure
      (env["clear"] || env).each { |k, v| ENV.delete(k) }
    end

    def read_dynamic_file(local_file)
      StringIO.new(ERB.new(IO.read(local_file)).result)
    end

    def expand_remote_file(remote_file)
      service_name + remote_file
    end

    def specific_volumes
      specifics["volumes"] || []
    end

    def remote_files_as_volumes
      specifics["files"]&.collect do |local_to_remote_mapping|
        _, remote_file = local_to_remote_mapping.split(":")
        "#{service_data_directory + remote_file}:#{remote_file}"
      end || []
    end

    def remote_directories_as_volumes
      specifics["directories"]&.collect do |host_to_container_mapping|
        host_path, container_path = host_to_container_mapping.split(":")
        [ expand_host_path(host_path), container_path ].join(":")
      end || []
    end

    def expand_host_path(host_path)
      absolute_path?(host_path) ? host_path : "#{service_data_directory}/#{host_path}"
    end

    def absolute_path?(path)
      Pathname.new(path).absolute?
    end

    def service_data_directory
      "$PWD/#{service_name}"
    end

    def hosts_from_host
      if specifics.key?("host")
        host = specifics["host"]
        if host
          [host]
        else
          raise ArgumentError, "Missing host for accessory `#{name}`"
        end
      end
    end

    def hosts_from_hosts
      if specifics.key?("hosts")
        hosts = specifics["hosts"]
        if hosts.is_a?(Array)
          hosts
        else
          raise ArgumentError, "Hosts should be an Array for accessory `#{name}`"
        end
      end
    end

    def hosts_from_roles
      if specifics.key?("roles")
        specifics["roles"].flat_map { |role| config.role(role).hosts }
      end
    end
end