class RBS::Repository

def self.default
  new().tap do |repo|
    repo.add(DEFAULT_STDLIB_ROOT)
  end
end

def self.find_best_version(version, candidates)
  candidates = candidates.sort
  return candidates.last || raise unless version
  if v = candidates.reverse.bsearch {|v| v <= version ? true : false }
    v
  else
    candidates.first or raise
  end
end

def add(dir)
  dirs << dir
  dir.each_child(false) do |child|
    gem_name = child.to_s
    gem_rbs = (gems[gem_name] ||= GemRBS.new(name: gem_name))
    gem_rbs.paths << dir + child
  end
end

def initialize(no_stdlib: false)
  @dirs = []
  @gems = {}
  unless no_stdlib
    add(DEFAULT_STDLIB_ROOT)
  end
end

def lookup(gem, version)
  _, set = lookup_path(gem, version)
  set&.path
end

def lookup_path(gem, version)
  if gem_rbs = gems[gem]
    unless gem_rbs.empty?
      set = if v = Gem::Version.create(version)&.release
        gem_rbs.find_best_version(v)
      else
        gem_rbs.latest_version
      end
      [gem_rbs, set]
    end
  end
end