class Doorkeeper::OAuth::Scopes

def self.from_array(array)
  new.tap do |scope|
    scope.add(*array)
  end
end

def self.from_string(string)
  string ||= ''
  new.tap do |scope|
    scope.add(*string.split)
  end
end

def &(other)
  other_array = other.present? ? other.all : []
  self.class.from_array(all & other_array)
end

def +(other)
  if other.is_a? Scopes
    self.class.from_array(all + other.all)
  else
    super(other)
  end
end

def <=>(other)
  map(&:to_s).sort <=> other.map(&:to_s).sort
end

def add(*scopes)
  @scopes.push(*scopes.map(&:to_s))
  @scopes.uniq!
end

def all
  @scopes
end

def exists?(scope)
  @scopes.include? scope.to_s
end

def has_scopes?(scopes)
  scopes.all? { |s| exists?(s) }
end

def initialize
  @scopes = []
end

def to_s
  @scopes.join(' ')
end