class Xcodeproj::Project::PBXObjectList

def <<(object)
  @callback.call(object) if @callback
end

def ==(other)
  self.to_a == other.to_a
end

def [](uuid)
  if hash = @scoped_hash[uuid]
    Project.const_get(hash['isa']).new(@project, uuid, hash)
  end
end

def add(klass, hash = {})
  object = klass.new(@project, nil, hash)
  @callback.call(object) if @callback
  object
end

def each
  @scoped_hash.keys.each do |uuid|
    yield self[uuid]
  end
end

def empty?
  @scoped_hash.empty?
end

def first
  to_a.first
end

def initialize(represented_class, project, scoped, &new_object_callback)
  @represented_class = represented_class
  @project           = project
  @scoped_hash       = scoped.is_a?(Array) ? scoped.inject({}) { |h, o| h[o.uuid] = o.attributes; h } : scoped
  @callback          = new_object_callback
end

def inspect
  "<PBXObjectList: #{map(&:inspect)}>"
end

def last
  to_a.last
end

def method_missing(name, *args, &block)
  if @represented_class.respond_to?(name)
    object = @represented_class.send(name, @project, *args)
    # The callbacks are only for PBXObject instances instantiated
    # from the class method that we forwarded the message to.
    @callback.call(object) if object.is_a?(PBXObject)
    object
  else
    super
  end
end

def new(hash = {})
  add(@represented_class, hash)
end

def select_by_class(klass)
  scoped = @scoped_hash.select { |_, attr| attr['isa'] == klass.isa }
  PBXObjectList.new(klass, @project, scoped) do |object|
    # Objects added to the subselection should still use the same
    # callback as this list.
    self << object
  end
end