drpheltright/pieces

module Pieces
  class ConfigNotFound < RuntimeError; end
  class PublisherConfigNotFound < RuntimeError; end

  class Config < Hash
    attr_reader :path
    attr_accessor :env

    def initialize(config = {})
      @path = config.delete(:path) || Dir.pwd
      merge!(config)
      load_config! unless config[:load] == false
    end

    def routes
      reject { |key, _| key =~ /^_/ }
    end

    def components_in_route(route)
      components_in_piece(routes[route])
    end

    def globals
      self['_global'] || {}
    end

    def publish_endpoint
      if has_key?('_publish')
        self['_publish'].first
      else
        raise PublisherConfigNotFound
      end
    end

    def asset_prefix
      self['_asset_prefix']
    end

    def mounted_at
      self['_mounted_at']
    end

    def reload!
      load_config!
    end

    private

    def load_config!
      if File.exists?("#{path}/config/pieces.yml")
        merge!(YAML.load_file("#{path}/config/pieces.yml"))
      else
        raise ConfigNotFound.new("We could not find pieces.yml in #{path}/config/")
      end
    end

    def components_in_piece(parent_piece)
      (parent_piece['_pieces'] || []).reduce([]) do |components, piece|
        piece_name, data = piece.first
        data = (parent_piece['_global'] || {}).merge(data['_global'] || {}).merge(data)
        components << [piece_name, data]
        components.concat(components_in_piece(data))
      end
    end
  end
end