# frozen_string_literal: true
require 'rubygems/command'

##
# Installs RubyGems itself.  This command is ordinarily only available from a
# RubyGems checkout or tarball.

class Gem::Commands::SetupCommand < Gem::Command

  HISTORY_HEADER = /^===\s*[\d.a-zA-Z]+\s*\/\s*\d{4}-\d{2}-\d{2}\s*$/.freeze
  VERSION_MATCHER = /^===\s*([\d.a-zA-Z]+)\s*\/\s*\d{4}-\d{2}-\d{2}\s*$/.freeze

  ENV_PATHS = %w[/usr/bin/env /bin/env].freeze

  def initialize
    require 'tmpdir'

    super 'setup', 'Install RubyGems',
          :format_executable => true, :document => %w[ri],
          :force => true,
          :site_or_vendor => 'sitelibdir',
          :destdir => '', :prefix => '', :previous_version => '',
          :regenerate_binstubs => true

    add_option '--previous-version=VERSION',
               'Previous version of RubyGems',
               'Used for changelog processing' do |version, options|
      options[:previous_version] = version
    end

    add_option '--prefix=PREFIX',
               'Prefix path for installing RubyGems',
               'Will not affect gem repository location' do |prefix, options|
      options[:prefix] = File.expand_path prefix
    end

    add_option '--destdir=DESTDIR',
               'Root directory to install RubyGems into',
               'Mainly used for packaging RubyGems' do |destdir, options|
      options[:destdir] = File.expand_path destdir
    end

    add_option '--[no-]vendor',
               'Install into vendorlibdir not sitelibdir' do |vendor, options|
      options[:site_or_vendor] = vendor ? 'vendorlibdir' : 'sitelibdir'
    end

    add_option '--[no-]format-executable',
               'Makes `gem` match ruby',
               'If Ruby is ruby18, gem will be gem18' do |value, options|
      options[:format_executable] = value
    end

    add_option '--[no-]document [TYPES]', Array,
               'Generate documentation for RubyGems',
               'List the documentation types you wish to',
               'generate.  For example: rdoc,ri' do |value, options|
      options[:document] = case value
                           when nil   then %w[rdoc ri]
                           when false then []
                           else            value
                           end
    end

    add_option '--[no-]rdoc',
               'Generate RDoc documentation for RubyGems' do |value, options|
      if value
        options[:document] << 'rdoc'
      else
        options[:document].delete 'rdoc'
      end

      options[:document].uniq!
    end

    add_option '--[no-]ri',
               'Generate RI documentation for RubyGems' do |value, options|
      if value
        options[:document] << 'ri'
      else
        options[:document].delete 'ri'
      end

      options[:document].uniq!
    end

    add_option '--[no-]regenerate-binstubs',
               'Regenerate gem binstubs' do |value, options|
      options[:regenerate_binstubs] = value
    end

    add_option '-f', '--[no-]force',
               'Forcefully overwrite binstubs' do |value, options|
      options[:force] = value
    end

    add_option('-E', '--[no-]env-shebang',
               'Rewrite executables with a shebang',
               'of /usr/bin/env') do |value, options|
      options[:env_shebang] = value
    end

    @verbose = nil
  end

  def check_ruby_version
    required_version = Gem::Requirement.new '>= 2.3.0'

    unless required_version.satisfied_by? Gem.ruby_version
      alert_error "Expected Ruby version #{required_version}, is #{Gem.ruby_version}"
      terminate_interaction 1
    end
  end

  def defaults_str # :nodoc:
    "--format-executable --document ri --regenerate-binstubs"
  end

  def description # :nodoc:
    <<-EOF
Installs RubyGems itself.

RubyGems installs RDoc for itself in GEM_HOME.  By default this is:
  #{Gem.dir}

If you prefer a different directory, set the GEM_HOME environment variable.

RubyGems will install the gem command with a name matching ruby's
prefix and suffix.  If ruby was installed as `ruby18`, gem will be
installed as `gem18`.

By default, this RubyGems will install gem as:
  #{Gem.default_exec_format % 'gem'}
    EOF
  end

  module MakeDirs
    def mkdir_p(path, **opts)
      super
      (@mkdirs ||= []) << path
    end
  end

  def execute
    @verbose = Gem.configuration.really_verbose

    install_destdir = options[:destdir]

    unless install_destdir.empty?
      ENV['GEM_HOME'] ||= File.join(install_destdir,
                                    Gem.default_dir.gsub(/^[a-zA-Z]:/, ''))
    end

    check_ruby_version

    require 'fileutils'
    if Gem.configuration.really_verbose
      extend FileUtils::Verbose
    else
      extend FileUtils
    end
    extend MakeDirs

    lib_dir, bin_dir = make_destination_dirs install_destdir

    install_lib lib_dir

    install_executables bin_dir

    remove_old_bin_files bin_dir

    remove_old_lib_files lib_dir

    install_default_bundler_gem bin_dir

    if mode = options[:dir_mode]
      @mkdirs.uniq!
      File.chmod(mode, @mkdirs)
    end

    say "RubyGems #{Gem::VERSION} installed"

    regenerate_binstubs if options[:regenerate_binstubs]

    uninstall_old_gemcutter

    documentation_success = install_rdoc

    say
    if @verbose
      say "-" * 78
      say
    end

    if options[:previous_version].empty?
      options[:previous_version] = Gem::VERSION.sub(/[0-9]+$/, '0')
    end

    options[:previous_version] = Gem::Version.new(options[:previous_version])

    show_release_notes

    say
    say "-" * 78
    say

    say "RubyGems installed the following executables:"
    say bin_file_names.map { |name| "\t#{name}\n" }
    say

    unless bin_file_names.grep(/#{File::SEPARATOR}gem$/)
      say "If `gem` was installed by a previous RubyGems installation, you may need"
      say "to remove it by hand."
      say
    end

    if documentation_success
      if options[:document].include? 'rdoc'
        say "Rdoc documentation was installed. You may now invoke:"
        say "  gem server"
        say "and then peruse beautifully formatted documentation for your gems"
        say "with your web browser."
        say "If you do not wish to install this documentation in the future, use the"
        say "--no-document flag, or set it as the default in your ~/.gemrc file. See"
        say "'gem help env' for details."
        say
      end

      if options[:document].include? 'ri'
        say "Ruby Interactive (ri) documentation was installed. ri is kind of like man "
        say "pages for Ruby libraries. You may access it like this:"
        say "  ri Classname"
        say "  ri Classname.class_method"
        say "  ri Classname#instance_method"
        say "If you do not wish to install this documentation in the future, use the"
        say "--no-document flag, or set it as the default in your ~/.gemrc file. See"
        say "'gem help env' for details."
        say
      end
    end
  end

  def install_executables(bin_dir)
    prog_mode = options[:prog_mode] || 0755

    executables = { 'gem' => 'bin' }
    executables.each do |tool, path|
      say "Installing #{tool} executable" if @verbose

      Dir.chdir path do
        bin_files = Dir['*']

        bin_files -= %w[update_rubygems]

        bin_files.each do |bin_file|
          dest_file = target_bin_path(bin_dir, bin_file)
          bin_tmp_file = File.join Dir.tmpdir, "#{bin_file}.#{$$}"

          begin
            bin = File.readlines bin_file
            bin[0] = shebang

            File.open bin_tmp_file, 'w' do |fp|
              fp.puts bin.join
            end

            install bin_tmp_file, dest_file, :mode => prog_mode
            bin_file_names << dest_file
          ensure
            rm bin_tmp_file
          end

          next unless Gem.win_platform?

          begin
            bin_cmd_file = File.join Dir.tmpdir, "#{bin_file}.bat"

            File.open bin_cmd_file, 'w' do |file|
              file.puts <<-TEXT
  @ECHO OFF
  IF NOT "%~f0" == "~f0" GOTO :WinNT
  @"#{File.basename(Gem.ruby).chomp('"')}" "#{dest_file}" %1 %2 %3 %4 %5 %6 %7 %8 %9
  GOTO :EOF
  :WinNT
  @"#{File.basename(Gem.ruby).chomp('"')}" "%~dpn0" %*
  TEXT
            end

            install bin_cmd_file, "#{dest_file}.bat", :mode => prog_mode
          ensure
            rm bin_cmd_file
          end
        end
      end
    end
  end

  def shebang
    if options[:env_shebang]
      ruby_name = RbConfig::CONFIG['ruby_install_name']
      @env_path ||= ENV_PATHS.find {|env_path| File.executable? env_path }
      "#!#{@env_path} #{ruby_name}\n"
    else
      "#!#{Gem.ruby}\n"
    end
  end

  def install_file(file, dest_dir)
    dest_file = File.join dest_dir, file
    dest_dir = File.dirname dest_file
    unless File.directory? dest_dir
      mkdir_p dest_dir, :mode => 0755
    end

    install file, dest_file, :mode => options[:data_mode] || 0644
  end

  def install_lib(lib_dir)
    libs = { 'RubyGems' => 'lib' }
    libs['Bundler'] = 'bundler/lib'
    libs.each do |tool, path|
      say "Installing #{tool}" if @verbose

      lib_files = rb_files_in path
      lib_files.concat(template_files) if tool == 'Bundler'

      pem_files = pem_files_in path

      Dir.chdir path do
        lib_files.each do |lib_file|
          install_file lib_file, lib_dir
        end

        pem_files.each do |pem_file|
          install_file pem_file, lib_dir
        end
      end
    end
  end

  def install_rdoc
    gem_doc_dir = File.join Gem.dir, 'doc'
    rubygems_name = "rubygems-#{Gem::VERSION}"
    rubygems_doc_dir = File.join gem_doc_dir, rubygems_name

    begin
      Gem.ensure_gem_subdirectories Gem.dir
    rescue SystemCallError
      # ignore
    end

    if File.writable? gem_doc_dir and
       (not File.exist? rubygems_doc_dir or
        File.writable? rubygems_doc_dir)
      say "Removing old RubyGems RDoc and ri" if @verbose
      Dir[File.join(Gem.dir, 'doc', 'rubygems-[0-9]*')].each do |dir|
        rm_rf dir
      end

      require 'rubygems/rdoc'

      fake_spec = Gem::Specification.new 'rubygems', Gem::VERSION
      def fake_spec.full_gem_path
        File.expand_path '../../../..', __FILE__
      end

      generate_ri   = options[:document].include? 'ri'
      generate_rdoc = options[:document].include? 'rdoc'

      rdoc = Gem::RDoc.new fake_spec, generate_rdoc, generate_ri
      rdoc.generate

      return true
    elsif @verbose
      say "Skipping RDoc generation, #{gem_doc_dir} not writable"
      say "Set the GEM_HOME environment variable if you want RDoc generated"
    end

    return false
  end

  def install_default_bundler_gem(bin_dir)
    specs_dir = Gem.default_specifications_dir
    specs_dir = File.join(options[:destdir], specs_dir) unless Gem.win_platform?
    mkdir_p specs_dir, :mode => 0755

    # Workaround for non-git environment.
    gemspec = File.open('bundler/bundler.gemspec', 'rb'){|f| f.read.gsub(/`git ls-files -z`/, "''") }
    File.open('bundler/bundler.gemspec', 'w'){|f| f.write gemspec }

    bundler_spec = Gem::Specification.load("bundler/bundler.gemspec")
    bundler_spec.files = Dir.chdir("bundler") { Dir["{*.md,{lib,exe,man}/**/*}"] }
    bundler_spec.executables -= %w[bundler bundle_ruby]

    # Remove bundler-*.gemspec in default specification directory.
    Dir.entries(specs_dir).
      select {|gs| gs.start_with?("bundler-") }.
      each {|gs| File.delete(File.join(specs_dir, gs)) }

    default_spec_path = File.join(specs_dir, "#{bundler_spec.full_name}.gemspec")
    Gem.write_binary(default_spec_path, bundler_spec.to_ruby)

    bundler_spec = Gem::Specification.load(default_spec_path)

    # Remove gemspec that was same version of vendored bundler.
    normal_gemspec = File.join(Gem.default_dir, "specifications", "bundler-#{bundler_spec.version}.gemspec")
    if File.file? normal_gemspec
      File.delete normal_gemspec
    end

    # Remove gem files that were same version of vendored bundler.
    if File.directory? bundler_spec.gems_dir
      Dir.entries(bundler_spec.gems_dir).
        select {|default_gem| File.basename(default_gem) == "bundler-#{bundler_spec.version}" }.
        each {|default_gem| rm_r File.join(bundler_spec.gems_dir, default_gem) }
    end

    bundler_bin_dir = bundler_spec.bin_dir
    bundler_bin_dir = File.join(options[:destdir], bundler_bin_dir) unless Gem.win_platform?
    mkdir_p bundler_bin_dir, :mode => 0755
    bundler_spec.executables.each do |e|
      cp File.join("bundler", bundler_spec.bindir, e), File.join(bundler_bin_dir, e)
    end

    require 'rubygems/installer'

    Dir.chdir("bundler") do
      built_gem = Gem::Package.build(bundler_spec)
      begin
        installer = Gem::Installer.at(built_gem, env_shebang: options[:env_shebang], format_executable: options[:format_executable], force: options[:force], install_as_default: true, bin_dir: bin_dir, wrappers: true)
        installer.install
      ensure
        FileUtils.rm_f built_gem
      end
    end

    bundler_spec.executables.each {|executable| bin_file_names << target_bin_path(bin_dir, executable) }

    say "Bundler #{bundler_spec.version} installed"
  end

  def make_destination_dirs(install_destdir)
    lib_dir, bin_dir = Gem.default_rubygems_dirs

    unless lib_dir
      lib_dir, bin_dir = generate_default_dirs(install_destdir)
    end

    mkdir_p lib_dir, :mode => 0755
    mkdir_p bin_dir, :mode => 0755

    return lib_dir, bin_dir
  end

  def generate_default_dirs(install_destdir)
    prefix = options[:prefix]
    site_or_vendor = options[:site_or_vendor]

    if prefix.empty?
      lib_dir = RbConfig::CONFIG[site_or_vendor]
      bin_dir = RbConfig::CONFIG['bindir']
    else
      # Apple installed RubyGems into libdir, and RubyGems <= 1.1.0 gets
      # confused about installation location, so switch back to
      # sitelibdir/vendorlibdir.
      if defined?(APPLE_GEM_HOME) and
        # just in case Apple and RubyGems don't get this patched up proper.
        (prefix == RbConfig::CONFIG['libdir'] or
         # this one is important
         prefix == File.join(RbConfig::CONFIG['libdir'], 'ruby'))
        lib_dir = RbConfig::CONFIG[site_or_vendor]
        bin_dir = RbConfig::CONFIG['bindir']
      else
        lib_dir = File.join prefix, 'lib'
        bin_dir = File.join prefix, 'bin'
      end
    end

    unless install_destdir.empty?
      lib_dir = File.join install_destdir, lib_dir.gsub(/^[a-zA-Z]:/, '')
      bin_dir = File.join install_destdir, bin_dir.gsub(/^[a-zA-Z]:/, '')
    end

    [lib_dir, bin_dir]
  end

  def pem_files_in(dir)
    Dir.chdir dir do
      Dir[File.join('**', '*pem')]
    end
  end

  def rb_files_in(dir)
    Dir.chdir dir do
      Dir[File.join('**', '*rb')]
    end
  end

  # for installation of bundler as default gems
  def template_files
    Dir.chdir "bundler/lib" do
      (Dir[File.join('bundler', 'templates', '**', '{*,.*}')]).
        select{|f| !File.directory?(f)}
    end
  end

  # for cleanup old bundler files
  def template_files_in(dir)
    Dir.chdir dir do
      (Dir[File.join('templates', '**', '{*,.*}')]).
        select{|f| !File.directory?(f)}
    end
  end

  def remove_old_bin_files(bin_dir)
    old_bin_files = {
      'gem_mirror' => 'gem mirror',
      'gem_server' => 'gem server',
      'gemlock' => 'gem lock',
      'gemri' => 'ri',
      'gemwhich' => 'gem which',
      'index_gem_repository.rb' => 'gem generate_index',
    }

    old_bin_files.each do |old_bin_file, new_name|
      old_bin_path = File.join bin_dir, old_bin_file
      next unless File.exist? old_bin_path

      deprecation_message = "`#{old_bin_file}` has been deprecated. Use `#{new_name}` instead."

      File.open old_bin_path, 'w' do |fp|
        fp.write <<-EOF
#!#{Gem.ruby}

abort "#{deprecation_message}"
    EOF
      end

      next unless Gem.win_platform?

      File.open "#{old_bin_path}.bat", 'w' do |fp|
        fp.puts %{@ECHO.#{deprecation_message}}
      end
    end
  end

  def remove_old_lib_files(lib_dir)
    lib_dirs = { File.join(lib_dir, 'rubygems') => 'lib/rubygems' }
    lib_dirs[File.join(lib_dir, 'bundler')] = 'bundler/lib/bundler'
    lib_dirs.each do |old_lib_dir, new_lib_dir|
      lib_files = rb_files_in(new_lib_dir)
      lib_files.concat(template_files_in(new_lib_dir)) if new_lib_dir =~ /bundler/

      old_lib_files = rb_files_in(old_lib_dir)
      old_lib_files.concat(template_files_in(old_lib_dir)) if old_lib_dir =~ /bundler/

      to_remove = old_lib_files - lib_files

      to_remove.delete_if do |file|
        file.start_with? 'defaults'
      end

      Dir.chdir old_lib_dir do
        to_remove.each do |file|
          FileUtils.rm_f file

          warn "unable to remove old file #{file} please remove it by hand" if
            File.exist? file
        end
      end
    end
  end

  def show_release_notes
    release_notes = File.join Dir.pwd, 'History.txt'

    release_notes =
      if File.exist? release_notes
        history = File.read release_notes

        history.force_encoding Encoding::UTF_8

        history = history.sub(/^# coding:.*?(?=^=)/m, '')

        text = history.split(HISTORY_HEADER)
        text.shift # correct an off-by-one generated by split
        version_lines = history.scan(HISTORY_HEADER)
        versions = history.scan(VERSION_MATCHER).flatten.map do |x|
          Gem::Version.new(x)
        end

        history_string = ""

        until versions.length == 0 or
              versions.shift <= options[:previous_version] do
          history_string += version_lines.shift + text.shift
        end

        history_string
      else
        "Oh-no! Unable to find release notes!"
      end

    say release_notes
  end

  def uninstall_old_gemcutter
    require 'rubygems/uninstaller'

    ui = Gem::Uninstaller.new('gemcutter', :all => true, :ignore => true,
                              :version => '< 0.4')
    ui.uninstall
  rescue Gem::InstallError
  end

  def regenerate_binstubs
    require "rubygems/commands/pristine_command"
    say "Regenerating binstubs"

    args = %w[--all --only-executables --silent]
    if options[:env_shebang]
      args << "--env-shebang"
    end

    command = Gem::Commands::PristineCommand.new
    command.invoke(*args)
  end

  private

  def target_bin_path(bin_dir, bin_file)
    bin_file_formatted = if options[:format_executable]
                           Gem.default_exec_format % bin_file
                         else
                           bin_file
                         end
    File.join bin_dir, bin_file_formatted
  end

  def bin_file_names
    @bin_file_names ||= []
  end

end