class Bundler::Fetcher::CompactIndex

def self.compact_index_request(method_name)
  method = instance_method(method_name)
  undef_method(method_name)
  define_method(method_name) do |*args, &blk|
    begin
      method.bind(self).call(*args, &blk)
    rescue NetworkDownError, CompactIndexClient::Updater::MisMatchedChecksumError => e
      raise HTTPError, e.message
    rescue AuthenticationRequiredError
      # We got a 401 from the server. Just fail.
      raise
    rescue HTTPError => e
      Bundler.ui.trace(e)
      nil
    end
  end
end

def api_fetcher?
  true
end

def available?
  # Read info file checksums out of /versions, so we can know if gems are up to date
  fetch_uri.scheme != "file" && compact_index_client.update_and_parse_checksums!
end

def cache_path
  Bundler.user_cache.join("compact_index", remote.cache_slug)
end

def compact_index_client
  @compact_index_client ||= begin
    compact_fetcher = lambda do |path, headers|
      downloader.fetch(fetch_uri + path, headers)
    end
    SharedHelpers.filesystem_access(cache_path) do
      CompactIndexClient.new(cache_path, compact_fetcher)
    end.tap do |client|
      client.in_parallel = lambda do |inputs, &blk|
        func = lambda {|object, _index| blk.call(object) }
        worker_name = "Compact Index (#{display_uri.host})"
        worker = Bundler::Worker.new(25, worker_name, func)
        inputs.each {|input| worker.enq(input) }
        inputs.map { worker.deq }
      end
    end
  end
end

def fetch_spec(spec)
  spec -= [nil, "ruby", ""]
  contents = compact_index_client.spec(*spec)
  return nil if contents.nil?
  contents.unshift(spec.first)
  contents[3].map! {|d| Gem::Dependency.new(*d) }
  EndpointSpecification.new(*contents)
end

def specs(gem_names)
  specs_for_names(gem_names)
end

def specs_for_names(gem_names)
  gem_info = []
  complete_gems = []
  remaining_gems = gem_names.dup
  until remaining_gems.empty?
    Bundler.ui.debug "Looking up gems #{remaining_gems.inspect}"
    deps = compact_index_client.dependencies(remaining_gems)
    next_gems = deps.map {|d| d[3].map(&:first).flatten(1) }.flatten(1).uniq
    deps.each {|dep| gem_info << dep }
    complete_gems.push(*deps.map(&:first)).uniq!
    remaining_gems = next_gems - complete_gems
  end
  gem_info
end