class Gem::Commands::EnvironmentCommand

def add_path(out, path)
  path.each do |component|
    out << "     - #{component}\n"
  end
end

def arguments # :nodoc:
  args = <<-EOF
        gemdir          display the path where gems are installed
        gempath         display path used to search for gems
        version         display the gem format version
        remotesources   display the remote gem servers
        platform        display the supported gem platforms
        <omitted>       display everything
  EOF
  return args.gsub(/^\s+/, '')
end

def description # :nodoc:
  <<-EOF
e environment command lets you query rubygems for its configuration for
e in shell scripts or as a debugging aid.
e RubyGems environment can be controlled through command line arguments,
mrc files, environment variables and built-in defaults.
mmand line argument defaults and some RubyGems defaults can be set in a
.gemrc file for individual users and a gemrc in the SYSTEM CONFIGURATION
RECTORY for all users. These files are YAML files with the following YAML
ys:
:sources: A YAML array of remote gem repositories to install gems from
:verbose: Verbosity of the gem command. false, true, and :really are the
          levels
:update_sources: Enable/disable automatic updating of repository metadata
:backtrace: Print backtrace when RubyGems encounters an error
:gempath: The paths in which to look for gems
:disable_default_gem_server: Force specification of gem server host on push
<gem_command>: A string containing arguments for the specified gem command
ample:
:verbose: false
install: --no-wrappers
update: --no-wrappers
:disable_default_gem_server: true
byGems' default local repository can be overridden with the GEM_PATH and
M_HOME environment variables. GEM_HOME sets the default repository to
stall into. GEM_PATH allows multiple local repositories to be searched for
ms.
 you are behind a proxy server, RubyGems uses the HTTP_PROXY,
TP_PROXY_USER and HTTP_PROXY_PASS environment variables to discover the
oxy server.
 you would like to push gems to a private gem server the RUBYGEMS_HOST
vironment variable can be set to the URI for that server.
 you are packaging RubyGems all of RubyGems' defaults are in
b/rubygems/defaults.rb.  You may override these in
b/rubygems/defaults/operating_system.rb
  EOF
end

def execute
  out = String.new
  arg = options[:args][0]
  out <<
    case arg
    when /^version/ then
      Gem::VERSION
    when /^gemdir/, /^gemhome/, /^home/, /^GEM_HOME/ then
      Gem.dir
    when /^gempath/, /^path/, /^GEM_PATH/ then
      Gem.path.join(File::PATH_SEPARATOR)
    when /^remotesources/ then
      Gem.sources.to_a.join("\n")
    when /^platform/ then
      Gem.platforms.join(File::PATH_SEPARATOR)
    when nil then
      show_environment
    else
      raise Gem::CommandLineError, "Unknown environment option [#{arg}]"
    end
  say out
  true
end

def git_path
  exts = ENV["PATHEXT"] ? ENV["PATHEXT"].split(";") : [""]
  ENV["PATH"].split(File::PATH_SEPARATOR).each do |path|
    exts.each do |ext|
      exe = File.join(path, "git#{ext}")
      return exe if File.executable?(exe) && !File.directory?(exe)
    end
  end
  return nil
end

def initialize
  super 'environment', 'Display information about the RubyGems environment'
end

def show_environment # :nodoc:
  out = "RubyGems Environment:\n".dup
  out << "  - RUBYGEMS VERSION: #{Gem::VERSION}\n"
  out << "  - RUBY VERSION: #{RUBY_VERSION} (#{RUBY_RELEASE_DATE}"
  out << " patchlevel #{RUBY_PATCHLEVEL}" if defined? RUBY_PATCHLEVEL
  out << ") [#{RUBY_PLATFORM}]\n"
  out << "  - INSTALLATION DIRECTORY: #{Gem.dir}\n"
  out << "  - USER INSTALLATION DIRECTORY: #{Gem.user_dir}\n"
  out << "  - RUBYGEMS PREFIX: #{Gem.prefix}\n" unless Gem.prefix.nil?
  out << "  - RUBY EXECUTABLE: #{Gem.ruby}\n"
  out << "  - GIT EXECUTABLE: #{git_path}\n"
  out << "  - EXECUTABLE DIRECTORY: #{Gem.bindir}\n"
  out << "  - SPEC CACHE DIRECTORY: #{Gem.spec_cache_dir}\n"
  out << "  - SYSTEM CONFIGURATION DIRECTORY: #{Gem::ConfigFile::SYSTEM_CONFIG_PATH}\n"
  out << "  - RUBYGEMS PLATFORMS:\n"
  Gem.platforms.each do |platform|
    out << "     - #{platform}\n"
  end
  out << "  - GEM PATHS:\n"
  out << "     - #{Gem.dir}\n"
  gem_path = Gem.path.dup
  gem_path.delete Gem.dir
  add_path out, gem_path
  out << "  - GEM CONFIGURATION:\n"
  Gem.configuration.each do |name, value|
    value = value.gsub(/./, '*') if name == 'gemcutter_key'
    out << "     - #{name.inspect} => #{value.inspect}\n"
  end
  out << "  - REMOTE SOURCES:\n"
  Gem.sources.each do |s|
    out << "     - #{s}\n"
  end
  out << "  - SHELL PATH:\n"
  shell_path = ENV['PATH'].split(File::PATH_SEPARATOR)
  add_path out, shell_path
  out
end

def usage # :nodoc:
  "#{program_name} [arg]"
end