module Puppet::Interface::FaceCollection

# File lib/puppet/interface/face_collection.rb, line 17
def self.[](name, version)
  name = underscorize(name)
  get_face(name, version) or load_face(name, version)
end

# File lib/puppet/interface/face_collection.rb, line 8
def self.faces
  unless @loaded
    @loaded = true
    names = @loader.files_to_load.map {|fn| ::File.basename(fn, '.rb')}.uniq
    names.each {|name| self[name, :current]}
  end
  @faces.keys.select {|name| @faces[name].length > 0 }
end

# File lib/puppet/interface/face_collection.rb, line 22
def self.get_action_for_face(name, action_name, version)
  name = underscorize(name)

  # If the version they request specifically doesn't exist, don't search
  # elsewhere.  Usually this will start from :current and all...
  return nil unless face = self[name, version]
  unless action = face.get_action(action_name)
    # ...we need to search for it bound to an o{lder,ther} version.  Since
    # we load all actions when the face is first references, this will be in
    # memory in the known set of versions of the face.
    (@faces[name].keys - [ :current ]).sort.reverse.each do |version|
      break if action = @faces[name][version].get_action(action_name)
    end
  end

  return action
end

# File lib/puppet/interface/face_collection.rb, line 41
def self.get_face(name, pattern)
  return nil unless @faces.has_key? name
  return @faces[name][:current] if pattern == :current

  versions = @faces[name].keys - [ :current ]
  found    = SemVer.find_matching(pattern, versions)
  return @faces[name][found]
end

# File lib/puppet/interface/face_collection.rb, line 51
def self.load_face(name, version)
  # We always load the current version file; the common case is that we have
  # the expected version and any compatibility versions in the same file,
  # the default.  Which means that this is almost always the case.
  #
  # We use require to avoid executing the code multiple times, like any
  # other Ruby library that we might want to use.  --daniel 2011-04-06
  if safely_require name then
    # If we wanted :current, we need to index to find that; direct version
    # requests just work as they go. --daniel 2011-04-06
    if version == :current then
      # We need to find current out of this.  This is the largest version
      # number that doesn't have a dedicated on-disk file present; those
      # represent "experimental" versions of faces, which we don't fully
      # support yet.
      #
      # We walk the versions from highest to lowest and take the first version
      # that is not defined in an explicitly versioned file on disk as the
      # current version.
      #
      # This constrains us to only ship experimental versions with *one*
      # version in the file, not multiple, but given you can't reliably load
      # them except by side-effect when you ignore that rule this seems safe
      # enough...
      #
      # Given those constraints, and that we are not going to ship a versioned
      # interface that is not :current in this release, we are going to leave
      # these thoughts in place, and just punt on the actual versioning.
      #
      # When we upgrade the core to support multiple versions we can solve the
      # problems then; as lazy as possible.
      #
      # We do support multiple versions in the same file, though, so we sort
      # versions here and return the last item in that set.
      #
      # --daniel 2011-04-06
      latest_ver = @faces[name].keys.sort.last
      @faces[name][:current] = @faces[name][latest_ver]
    end
  end

  unless version == :current or get_face(name, version)
    # Try an obsolete version of the face, if needed, to see if that helps?
    safely_require name, version
  end

  return get_face(name, version)
end

# File lib/puppet/interface/face_collection.rb, line 116
def self.register(face)
  @faces[underscorize(face.name)][face.version] = face
end

# File lib/puppet/interface/face_collection.rb, line 100
def self.safely_require(name, version = nil)
  path = @loader.expand(version ? ::File.join(version.to_s, name.to_s) : name)
  require path
  true

rescue LoadError => e
  raise unless e.message =~ %r{-- #{path}$}
  # ...guess we didn't find the file; return a much better problem.
  nil
rescue SyntaxError => e
  raise unless e.message =~ %r{#{path}\.rb:\d+: }
  Puppet.err "Failed to load face #{name}:\n#{e}"
  # ...but we just carry on after complaining.
  nil
end

# File lib/puppet/interface/face_collection.rb, line 120
def self.underscorize(name)
  unless name.to_s =~ /^[-_a-z][-_a-z0-9]*$/ then
    raise ArgumentError, "#{name.inspect} (#{name.class}) is not a valid face name"
  end

  name.to_s.downcase.split(/[-_]/).join('_').to_sym
end