class Gem::Source::Local

def <=>(other)
  case other
  when Gem::Source::Installed,
       Gem::Source::Lock then
    -1
  when Gem::Source::Local then
    0
  when Gem::Source then
    1
  end
end

def download(spec, cache_dir = nil) # :nodoc:
  load_specs :complete
  @specs.each do |_name, data|
    return data[0] if data[1].spec == spec
  end
  raise Gem::Exception, "Unable to find file for '#{spec.full_name}'"
end

def fetch_spec(name) # :nodoc:
  load_specs :complete
  if data = @specs[name]
    data.last.spec
  else
    raise Gem::Exception, "Unable to find spec for #{name.inspect}"
  end
end

def find_gem(gem_name, version = Gem::Requirement.default, prerelease = false) # :nodoc:
  load_specs :complete
  found = []
  @specs.each do |n, data|
    next unless n.name == gem_name
    s = data[1].spec
    if version.satisfied_by?(s.version)
      if prerelease
        found << s
      elsif !s.version.prerelease? || version.prerelease?
        found << s
      end
    end
  end
  found.max_by(&:version)
end

def initialize # :nodoc:
  @specs   = nil
  @api_uri = nil
  @uri     = nil
  @load_specs_names = {}
end

def inspect # :nodoc:
  keys = @specs ? @specs.keys.sort : "NOT LOADED"
  format("#<%s specs: %p>", self.class, keys)
end

def load_specs(type) # :nodoc:
  @load_specs_names[type] ||= begin
    names = []
    @specs = {}
    Dir["*.gem"].each do |file|
      pkg = Gem::Package.new(file)
      spec = pkg.spec
    rescue SystemCallError, Gem::Package::FormatError
      # ignore
    else
      tup = spec.name_tuple
      @specs[tup] = [File.expand_path(file), pkg]
      case type
      when :released
        unless pkg.spec.version.prerelease?
          names << pkg.spec.name_tuple
        end
      when :prerelease
        if pkg.spec.version.prerelease?
          names << pkg.spec.name_tuple
        end
      when :latest
        tup = pkg.spec.name_tuple
        cur = names.find {|x| x.name == tup.name }
        if !cur
          names << tup
        elsif cur.version < tup.version
          names.delete cur
          names << tup
        end
      else
        names << pkg.spec.name_tuple
      end
    end
    names
  end
end

def pretty_print(q) # :nodoc:
  q.object_group(self) do
    q.group 2, "[Local gems:", "]" do
      q.breakable
      if @specs
        q.seplist @specs.keys do |v|
          q.text v.full_name
        end
      end
    end
  end
end