class Gemlist

# File lib/gemlist.rb, line 7
def initialize(path, options = {})
  @path    = Pathname.new(path)
  @options = options
end

# File lib/gemlist.rb, line 19
def gems
  cached_specs = specs

  cached_specs.each.with_index.with_object([]) do |(spec, index), uniquified_specs|
    last_occurrence_of_spec = cached_specs.rindex(spec) == index

    uniquified_specs << spec if last_occurrence_of_spec
  end
end

# File lib/gemlist.rb, line 12
def sources
  lockfile_parser.sources
    .select { |source| source.is_a?(Bundler::Source::Rubygems) }
    .flat_map(&:remotes)
    .map(&:to_s)
end

# File lib/gemlist.rb, line 47
def bundle_definition
  return @bundle_definition unless @bundle_definition.nil?

  builder = Bundler::Dsl.new
  builder.eval_gemfile(path/"Gemfile")

  @bundle_definition = builder.to_definition(path/"Gemfile.lock", {})
end

# File lib/gemlist.rb, line 60
def groups
  excluded_groups = options.fetch(:without) { [] }
  included_groups = options.fetch(:with) { [] }

  intersection    = excluded_groups & included_groups

  raise GroupConflict.new(*intersection) if intersection.any?

  bundle_definition.groups + included_groups - excluded_groups
end

# File lib/gemlist.rb, line 56
def lockfile_parser
  @lockfile_parser = Bundler::LockfileParser.new((path/"Gemfile.lock").read)
end

# File lib/gemlist.rb, line 31
def specs
  spec_tree = SpecTree.new(lockfile_parser)

  spec_tree
    .depth_first_children_first
    .reject(&:root?)
    .select { |node| node.descends_from?(*top_level_dependencies) }
    .map(&:content)
end

# File lib/gemlist.rb, line 41
def top_level_dependencies
  bundle_definition
    .dependencies
    .select { |dependency| (dependency.groups & groups).any? }
end