class Gem::Uninstaller

# File lib/rubygems/uninstaller.rb, line 44
def initialize(gem, options = {})
  # TODO document the valid options
  @gem                = gem
  @version            = options[:version] || Gem::Requirement.default
  @gem_home           = File.expand_path(options[:install_dir] || Gem.dir)
  @force_executables  = options[:executables]
  @force_all          = options[:all]
  @force_ignore       = options[:ignore]
  @bin_dir            = options[:bin_dir]
  @format_executable  = options[:format_executable]
  @abort_on_dependent = options[:abort_on_dependent]

  # Indicate if development dependencies should be checked when
  # uninstalling. (default: false)
  #
  @check_dev         = options[:check_dev]

  if options[:force]
    @force_all = true
    @force_ignore = true
  end

  # only add user directory if install_dir is not set
  @user_install = false
  @user_install = options[:user_install] unless options[:install_dir]
end

# File lib/rubygems/uninstaller.rb, line 280
def path_ok?(gem_dir, spec)
  full_path     = File.join gem_dir, 'gems', spec.full_name
  original_path = File.join gem_dir, 'gems', spec.original_name

  full_path == spec.full_gem_path || original_path == spec.full_gem_path
end

# File lib/rubygems/uninstaller.rb, line 239
def remove(spec)
  unless path_ok?(@gem_home, spec) or
         (@user_install and path_ok?(Gem.user_dir, spec)) then
    e = Gem::GemNotInHomeException.new              "Gem '#{spec.full_name}' is not installed in directory #{@gem_home}"
    e.spec = spec

    raise e
  end

  raise Gem::FilePermissionError, spec.base_dir unless
    File.writable?(spec.base_dir)

  FileUtils.rm_rf spec.full_gem_path
  FileUtils.rm_rf spec.extension_dir

  old_platform_name = spec.original_name
  gemspec           = spec.spec_file

  unless File.exist? gemspec then
    gemspec = File.join(File.dirname(gemspec), "#{old_platform_name}.gemspec")
  end

  FileUtils.rm_rf gemspec

  gem = spec.cache_file
  gem = File.join(spec.cache_dir, "#{old_platform_name}.gem") unless
    File.exist? gem

  FileUtils.rm_rf gem

  Gem::RDoc.new(spec).remove

  say "Successfully uninstalled #{spec.full_name}"

  Gem::Specification.reset
end

# File lib/rubygems/uninstaller.rb, line 228
def remove_all(list)
  list.each { |spec| uninstall_gem spec }
end

# File lib/rubygems/uninstaller.rb, line 174
def remove_executables(spec)
  return if spec.nil? or spec.executables.empty?

  executables = spec.executables.clone

  # Leave any executables created by other installed versions
  # of this gem installed.

  list = Gem::Specification.find_all { |s|
    s.name == spec.name && s.version != spec.version
  }

  list.each do |s|
    s.executables.each do |exe_name|
      executables.delete exe_name
    end
  end

  return if executables.empty?

  executables = executables.map { |exec| formatted_program_filename exec }

  remove = if @force_executables.nil? then
             ask_yes_no("Remove executables:\n" +
                        "\t#{executables.join ', '}\n\n" +
                        "in addition to the gem?",
                        true)
           else
             @force_executables
           end

  if remove then
    bin_dir = @bin_dir || Gem.bindir(spec.base_dir)

    raise Gem::FilePermissionError, bin_dir unless File.writable? bin_dir

    executables.each do |exe_name|
      say "Removing #{exe_name}"

      exe_file = File.join bin_dir, exe_name

      FileUtils.rm_f exe_file
      FileUtils.rm_f "#{exe_file}.bat"
    end
  else
    say "Executables and scripts will remain installed."
  end
end

# File lib/rubygems/uninstaller.rb, line 75
def uninstall
  dependency = Gem::Dependency.new @gem, @version

  list = []

  dirs =
    Gem::Specification.dirs +
    [Gem::Specification.default_specifications_dir]

  Gem::Specification.each_spec dirs do |spec|
    next unless dependency.matches_spec? spec

    list << spec
  end

  default_specs, list = list.partition do |spec|
    spec.default_gem?
  end

  list, other_repo_specs = list.partition do |spec|
    @gem_home == spec.base_dir or
      (@user_install and spec.base_dir == Gem.user_dir)
  end

  list.sort!

  if list.empty? then
    if other_repo_specs.empty?
      if default_specs.empty?
        raise Gem::InstallError, "gem #{@gem.inspect} is not installed"
      else
        message =
          "gem #{@gem.inspect} cannot be uninstalled " +
          "because it is a default gem"
        raise Gem::InstallError, message
      end
    end

    other_repos = other_repo_specs.map { |spec| spec.base_dir }.uniq

    message = ["#{@gem} is not installed in GEM_HOME, try:"]
    message.concat other_repos.map { |repo|
      "\tgem uninstall -i #{repo} #{@gem}"
    }

    raise Gem::InstallError, message.join("\n")
  elsif @force_all then
    remove_all list

  elsif list.size > 1 then
    gem_names = list.map { |gem| gem.full_name }
    gem_names << "All versions"

    say
    _, index = choose_from_list "Select gem to uninstall:", gem_names

    if index == list.size then
      remove_all list
    elsif index >= 0 && index < list.size then
      uninstall_gem list[index]
    else
      say "Error: must enter a number [1-#{list.size+1}]"
    end
  else
    uninstall_gem list.first
  end
end

# File lib/rubygems/uninstaller.rb, line 146
def uninstall_gem(spec)
  @spec = spec

  unless dependencies_ok? spec
    if abort_on_dependent? || !ask_if_ok(spec)
      raise Gem::DependencyRemovalException,
        "Uninstallation aborted due to dependent gem(s)"
    end
  end

  Gem.pre_uninstall_hooks.each do |hook|
    hook.call self
  end

  remove_executables @spec
  remove @spec

  Gem.post_uninstall_hooks.each do |hook|
    hook.call self
  end

  @spec = nil
end