Class Gem::SpecFetcher < Object

# File ../ruby/lib/rubygems/spec_fetcher.rb, line 42
def self.fetcher
  @fetcher ||= new
end

# File ../ruby/lib/rubygems/spec_fetcher.rb, line 50
def initialize
  require 'fileutils'

  @dir = File.join Gem.user_home, '.gem', 'specs'
  @update_cache = File.stat(Gem.user_home).uid == Process.uid

  @specs = {}
  @latest_specs = {}
  @prerelease_specs = {}

  @caches = {
    :latest => @latest_specs,
    :prerelease => @prerelease_specs,
    :all => @specs
  }

  @fetcher = Gem::RemoteFetcher.fetcher
end

# File ../ruby/lib/rubygems/spec_fetcher.rb, line 72
def cache_dir(uri)
  # Correct for windows paths
  escaped_path = uri.path.sub(/^\/([a-z]):\//i, '/\1-/')
  File.join @dir, "#{uri.host}%#{uri.port}", File.dirname(escaped_path)
end

# File ../ruby/lib/rubygems/spec_fetcher.rb, line 101
def fetch(*args)
  fetch_with_errors(*args).first
end

# File ../ruby/lib/rubygems/spec_fetcher.rb, line 105
def fetch_spec(spec, source_uri)
  source_uri = URI.parse source_uri if String === source_uri
  spec = spec - [nil, 'ruby', '']
  spec_file_name = "#{spec.join '-'}.gemspec"

  uri = source_uri + "#{Gem::MARSHAL_SPEC_DIR}#{spec_file_name}"

  cache_dir = cache_dir uri

  local_spec = File.join cache_dir, spec_file_name

  if File.exist? local_spec then
    spec = Gem.read_binary local_spec
  else
    uri.path << '.rz'

    spec = @fetcher.fetch_path uri
    spec = Gem.inflate spec

    if @update_cache then
      FileUtils.mkdir_p cache_dir

      open local_spec, 'wb' do |io|
        io.write spec
      end
    end
  end

  # TODO: Investigate setting Gem::Specification#loaded_from to a URI
  Marshal.load spec
end

# File ../ruby/lib/rubygems/spec_fetcher.rb, line 84
def fetch_with_errors(dependency,
                      all               = false,
                      matching_platform = true,
                      prerelease        = false)

  specs_and_sources, errors = find_matching_with_errors(dependency,
                                                        all,
                                                        matching_platform,
                                                        prerelease)

  ss = specs_and_sources.map do |spec_tuple, source_uri|
    [fetch_spec(spec_tuple, URI.parse(source_uri)), source_uri]
  end

  return [ss, errors]
end

# File ../ruby/lib/rubygems/spec_fetcher.rb, line 176
def find_matching(*args)
  find_matching_with_errors(*args).first
end

# File ../ruby/lib/rubygems/spec_fetcher.rb, line 142
def find_matching_with_errors(dependency,
                              all               = false,
                              matching_platform = true,
                              prerelease        = false)
  found = {}

  rejected_specs = {}

  list(all, prerelease).each do |source_uri, specs|
    found[source_uri] = specs.select do |spec_name, version, spec_platform|
      if dependency.match?(spec_name, version)
        if matching_platform and !Gem::Platform.match(spec_platform)
          pm = (rejected_specs[dependency] ||= Gem::PlatformMismatch.new(spec_name, version))
          pm.add_platform spec_platform
          false
        else
          true
        end
      end
    end
  end

  errors = rejected_specs.values

  specs_and_sources = []

  found.each do |source_uri, specs|
    uri_str = source_uri.to_s
    specs_and_sources.concat(specs.map { |spec| [spec, uri_str] })
  end

  [specs_and_sources, errors]
end

# File ../ruby/lib/rubygems/spec_fetcher.rb, line 213
def list(all = false, prerelease = false)
  # TODO: make type the only argument
  type = if all
           :all
         elsif prerelease
           :prerelease
         else
           :latest
         end

  list  = {}
  file  = FILES[type]
  cache = @caches[type]

  Gem.sources.each do |source_uri|
    source_uri = URI.parse source_uri

    unless cache.include? source_uri
      cache[source_uri] = load_specs source_uri, file
    end

    list[source_uri] = cache[source_uri]
  end

  if type == :all
    list.values.map do |gems|
      gems.reject! { |g| !g[1] || g[1].prerelease? }
    end
  end

  list
end

# File ../ruby/lib/rubygems/spec_fetcher.rb, line 250
def load_specs(source_uri, file)
  file_name  = "#{file}.#{Gem.marshal_version}"
  spec_path  = source_uri + "#{file_name}.gz"
  cache_dir  = cache_dir spec_path
  local_file = File.join(cache_dir, file_name)
  loaded     = false

  if File.exist? local_file then
    begin
      spec_dump =
        @fetcher.fetch_path(spec_path, File.mtime(local_file))
    rescue Gem::RemoteFetcher::FetchError => e
      alert_warning "Error fetching data: #{e.message}"
    end

    loaded = true if spec_dump

    spec_dump ||= Gem.read_binary local_file
  else
    spec_dump = @fetcher.fetch_path spec_path
    loaded = true
  end

  specs = begin
            Marshal.load spec_dump
          rescue ArgumentError
            spec_dump = @fetcher.fetch_path spec_path
            loaded = true

            Marshal.load spec_dump
          end

  if loaded and @update_cache then
    begin
      FileUtils.mkdir_p cache_dir

      open local_file, 'wb' do |io|
        io << spec_dump
      end
    rescue
    end
  end

  specs
end

# File ../ruby/lib/rubygems/spec_fetcher.rb, line 186
def suggest_gems_from_name gem_name
  gem_name        = gem_name.downcase
  max             = gem_name.size / 2
  specs           = list.values.flatten 1

  matches = specs.map { |name, version, platform|
    next unless Gem::Platform.match platform

    distance = levenshtein_distance gem_name, name.downcase

    next if distance >= max

    return [name] if distance == 0

    [name, distance]
  }.compact

  matches = matches.uniq.sort_by { |name, dist| dist }

  matches.first(5).map { |name, dist| name }
end