require 'r10k'
require 'r10k/synchro/git'
require 'r10k/environment_collection'
require 'yaml'

class R10K::Deployment
  # Model a full installation of module directories and modules.

  def self.instance
    @myself ||= self.new
  end

  def initialize
    @configfile   = File.join(Dir.getwd, "config.yaml")
    @update_cache = true
  end

  attr_accessor :configfile

  # Load up all module roots
  #
  # @return [Array<R10K::Root>]
  def environments
    collection = R10K::EnvironmentCollection.new(config)
    collection.to_a
  end

  # Serve up the loaded config if it's already been loaded, otherwise try to
  # load a config in the current wd.
  def config
    load_config unless @config
    @config
  end

  # @return [Object] A top level key from the config hash
  def setting(key)
    self.config[key]
  end
  alias_method :[], :setting

  private

  # Load and store a config file, and set relevant options
  #
  # @param [String] configfile The path to the YAML config file
  def load_config
    File.open(@configfile) { |fh| @config = YAML.load(fh.read) }
    apply_config_settings
    @config
  rescue => e
    raise "Couldn't load #{configfile}: #{e}"
  end

  # Apply config settings to the relevant classes after a config has been loaded.
  def apply_config_settings
    if @config[:cachedir]
      R10K::Synchro::Git.cache_root = @config[:cachedir]
    end
  end
end