module Sideload

# File lib/sideload.rb, line 15
def init
  c = Config.new
  yield(c)
  return c
end

# File lib/sideload.rb, line 11
def logger=(logger)
  @logger = logger
end

# File lib/sideload.rb, line 21
def update!(sources)
  scope, arg, _config, validate = sources.shift
  mod = const_get(scope.to_s.capitalize)
  contents = mod.read(*arg)
  unless sources.empty?
    next_layer = update!(sources)
    unless next_layer.nil?
      (contents.keys | next_layer.keys).each do |key|
        if !next_layer.has_key?(key)
          mod.with(arg, key) do |fp, t|
            mod.delete(fp, t)
          end
        else
          mod.with(arg, key) do |fp, t|
            mod.write(fp, t, next_layer[key], &validate)
          end
        end
      end
      contents = mod.read(arg)
    end
  end
  contents.each(&Proc.new) if block_given?
  return contents
rescue ValidationError => e
  if @logger
    @logger.error { [e.class, e.message].inspect }
    @logger.debug { e.backtrace.join("\n") }
  end
  return nil
end